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Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2012	Mar. 01, 2013	Jun. 30, 2012
Document and Entity Information
Entity Registrant Name	AMICUS THERAPEUTICS INC
Entity Central Index Key	0001178879
Document Type	10-K
Document Period End Date	Dec. 31, 2012
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Public Float			$ 104,283,867
Entity Common Stock, Shares Outstanding		49,631,672
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	FY

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 33,971	$ 25,668
Investments in marketable securities	65,151	30,034
Receivable due from GSK	3,225	5,043
Prepaid expenses and other current assets	2,270	5,903
Total current assets	104,617	66,648
Property and equipment, less accumulated depreciation and amortization of $9,507 and $8,501 at December 31, 2011 and 2012, respectively	5,029	2,438
Other non-current assets	442	709
Total Assets	110,088	69,795
Current liabilities:
Accounts payable and accrued expenses	8,845	9,708
Current portion of deferred reimbursements		8,504
Current portion of secured loan	398	1,044
Total current liabilities	9,243	19,256
Deferred reimbursements, less current portion	30,418	18,999
Warrant liability	908	1,948
Secured loan, less current portion	299
Commitments and contingencies
Stockholders' equity:
Common stock, $.01 par value, 125,000,000 shares authorized, 34,654,206 shares issued and outstanding at December 31, 2011, 49,631,672 shares issued and outstanding at December 31, 2012	556	407
Additional paid-in capital	387,539	299,285
Accumulated other comprehensive income	14	4
Deficit accumulated during the development stage	(318,889)	(270,104)
Total stockholders' equity	69,220	29,592
Total Liabilities and Stockholders' Equity	$ 110,088	$ 69,795

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2012	Dec. 31, 2011
Consolidated Balance Sheets
Accumulated depreciation and amortization of property and equipment (in dollars)	$ 8,501	$ 9,507
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	125,000,000	125,000,000
Common stock, shares issued	49,631,672	34,654,206
Common stock, shares outstanding	49,631,672	34,654,206

- Definition

The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.

+ References + Details

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended			131 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012
Revenue:
Research revenue	$ 11,591	$ 14,794		$ 57,493
Collaboration and milestone revenue	6,820	6,640	$ 922	64,382
Total revenue	18,411	21,434	922	121,875
Operating Expenses:
Research and development	50,273	50,856	39,042	315,893
General and administrative	19,364	19,880	15,660	132,613
Restructuring charges				1,522
Impairment of leasehold improvements				1,030
Depreciation and amortization	1,705	1,585	2,058	11,768
In-process research and development				418
Total operating expenses	71,342	72,321	56,760	463,244
Loss from operations	(52,931)	(50,887)	(55,838)	(341,369)
Other income (expenses):
Interest income	316	160	156	14,389
Interest expense	(89)	(148)	(260)	(2,422)
Change in fair value of warrant liability	653	2,764	(1,410)	1,553
Other income	21	70	1,277	252
Loss before income tax benefit	(52,030)	(48,041)	(56,075)	(327,597)
Income tax benefit	3,245	3,629	1,139	8,708
Net loss	(48,785)	(44,412)	(54,936)	(318,889)
Deemed dividend				(19,424)
Preferred stock accretion				(802)
Net loss attributable to common stockholders	$ (48,785)	$ (44,412)	$ (54,936)	$ (339,115)
Net loss attributable to common stockholders per common share - basic and diluted (in dollars per share)	$ (1.07)	$ (1.28)	$ (1.98)
Weighted-average common shares outstanding - basic and diluted (in shares)	45,565,217	34,569,642	27,734,797

Consolidated Statements of Comprehensive Loss - USD ($)
$ in Thousands

12 Months Ended

131 Months Ended

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2010

Dec. 31, 2012

Consolidated Statements of Comprehensive Loss

Net loss

$ (48,785)

$ (44,412)

$ (54,936)

$ (318,889)

Other comprehensive income/(loss):

Unrealized (loss)/gain on available-for-sale securities

(71)

Other comprehensive (loss)/income before income taxes

(71)

Provision for income taxes related to other comprehensive (loss)/income items (a)

^[1]

Other comprehensive (loss)/income

(71)

Comprehensive loss

$ (48,775)

$ (44,380)

$ (55,007)

$ (318,875)

[1]	(a) — Taxes have not been accrued on unrealized gain on securities as the Company is in a loss position for all periods presented.

- Definition

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References + Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

- Definition

Before tax amount of other comprehensive income (loss) attributable to the parent entity.

+ References

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- Definition

Net of tax amount of other comprehensive income (loss) attributable to the parent entity.

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+ Details

- Definition

Net of tax amount of unrealized holding gain (loss) before reclassification adjustments and transfers on available-for-sale securities.

+ References

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+ Details

Consolidated Statements of Changes in Stockholders' (Deficiency)/Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Other Comprehensive Gain/ (Loss)	Deferred Compensation	Deficit Accumulated During the Development Stage
Balance at Feb. 03, 2002		$ 0		$ 0
Increase (Decrease) in Stockholders' Equity
Issuance of common stock	$ 84	$ 6	$ 78
Issuance of common stock (in shares)		74,938
Stock issued for in-process research and development	418	$ 17	401
Stock issued for in-process research and development (in shares)		232,266
Deferred compensation			209		$ (209)
Amortization of deferred compensation	27				27
Issuance of warrants	8		8
Accretion of redeemable convertible preferred stock	(11)		(11)
Comprehensive (Loss)/ Income:
Net loss	(1,775)					$ (1,775)
Balance at Dec. 31, 2002	(1,249)	$ 23	685		(182)	(1,775)
Balance (in shares) at Dec. 31, 2002		307,204
Balance at Feb. 03, 2002		$ 0		0
Comprehensive (Loss)/ Income:
Unrealized holding gain (loss) on available-for-sale securities	14
Net loss	(318,889)
Balance at Dec. 31, 2012	$ 69,220	$ 556	387,539	14		(318,889)
Balance (in shares) at Dec. 31, 2012	49,631,672	49,631,672
Balance at Dec. 31, 2002	$ (1,249)	$ 23	685		(182)	(1,775)
Balance (in shares) at Dec. 31, 2002		307,204
Increase (Decrease) in Stockholders' Equity
Stock issued from exercise of stock options, net (in shares)		333
Deferred compensation			14		(14)
Amortization of deferred compensation	70				70
Issuance of warrants	210		210
Issuance of stock options to consultants	4		4
Accretion of redeemable convertible preferred stock	(17)		(17)
Beneficial conversion on issuance of Series C redeemable convertible preferred stock	41		41
Comprehensive (Loss)/ Income:
Net loss	(6,768)					(6,768)
Balance at Dec. 31, 2003	(7,709)	$ 23	937		(126)	(8,543)
Balance (in shares) at Dec. 31, 2003		307,537
Increase (Decrease) in Stockholders' Equity
Deferred compensation			68		(68)
Amortization of deferred compensation	60				60
Issuance of stock options to consultants	16		16
Interest waived on converted convertible notes	193		193
Accretion of redeemable convertible preferred stock	(126)		(126)
Beneficial conversion on issuance of Series C redeemable convertible preferred stock	95		95
Comprehensive (Loss)/ Income:
Unrealized holding gain (loss) on available-for-sale securities	(9)			(9)
Net loss	(8,807)					(8,807)
Balance at Dec. 31, 2004	(16,287)	$ 23	1,183	(9)	(134)	(17,350)
Balance (in shares) at Dec. 31, 2004		307,537
Increase (Decrease) in Stockholders' Equity
Stock issued from exercise of stock options, net	24	$ 7	17
Stock issued from exercise of stock options, net (in shares)		97,156
Stock issued from exercise of warrants	75	$ 10	65
Stock issued from exercise of warrants (in shares)		133,332
Deferred compensation			2,778		(2,778)
Amortization of deferred compensation	365				365
Issuance of stock options to consultants	112		112
Accretion of redeemable convertible preferred stock	(139)		(139)
Comprehensive (Loss)/ Income:
Unrealized holding gain (loss) on available-for-sale securities	(7)			(7)
Net loss	(19,972)					(19,972)
Balance at Dec. 31, 2005	(35,829)	$ 40	4,016	(16)	(2,547)	(37,322)
Balance (in shares) at Dec. 31, 2005		538,025
Increase (Decrease) in Stockholders' Equity
Stock issued from exercise of stock options, net	158	$ 20	138
Stock issued from exercise of stock options, net (in shares)		265,801
Stock issued for license payment	1,220	$ 10	1,210
Stock issued for license payment (in shares)		133,333
Reversal of deferred compensation upon adoption of FAS 123(R)			(2,547)		$ 2,547
Issuance of stock options to consultants	476		476
Stock-based compensation	2,816		2,816
Stock-based compensation (in shares)		53,333
Accretion of redeemable convertible preferred stock	(159)		(159)
Reclassification of warrant liability upon exercise of Series B redeemable convertible preferred stock warrants	117		117
Beneficial conversion on issuance of Series C redeemable convertible preferred stock	19,424		19,424
Beneficial conversion charge (deemed dividend) on issuance of Series C redeemable convertible preferred stock	(19,424)		(19,424)
Comprehensive (Loss)/ Income:
Unrealized holding gain (loss) on available-for-sale securities	31			31
Net loss	(46,345)					(46,345)
Balance at Dec. 31, 2006	(77,515)	$ 70	6,067	15		(83,667)
Balance (in shares) at Dec. 31, 2006		990,492
Increase (Decrease) in Stockholders' Equity
Issuance of common stock	68,145	$ 50	68,095
Issuance of common stock (in shares)		5,000,000
Stock issued from conversion of preferred shares	148,591	$ 162	148,429
Stock issued from conversion of preferred shares (in shares)		16,112,721
Stock issued from exercise of stock options, net	458	$ 3	455
Stock issued from exercise of stock options, net (in shares)		305,518
Issuance of stock options to consultants	162		162
Stock-based compensation	3,823		3,823
Accretion of redeemable convertible preferred stock	(351)		(351)
Charge for warrant liability	758		758
Comprehensive (Loss)/ Income:
Unrealized holding gain (loss) on available-for-sale securities	393			393
Net loss	(41,167)					(41,167)
Balance at Dec. 31, 2007	103,297	$ 285	227,438	408		(124,834)
Balance (in shares) at Dec. 31, 2007		22,408,731
Increase (Decrease) in Stockholders' Equity
Stock issued from exercise of stock options, net	530	$ 2	528
Stock issued from exercise of stock options, net (in shares)		225,980
Stock-based compensation	6,446		6,446
Comprehensive (Loss)/ Income:
Unrealized holding gain (loss) on available-for-sale securities	125			125
Net loss	(39,355)					(39,355)
Balance at Dec. 31, 2008	71,043	$ 287	234,412	533		(164,189)
Balance (in shares) at Dec. 31, 2008		22,634,711
Increase (Decrease) in Stockholders' Equity
Stock issued from exercise of stock options, net	60		60
Stock issued from exercise of stock options, net (in shares)		37,716
Stock-based compensation	7,787		7,787
Comprehensive (Loss)/ Income:
Unrealized holding gain (loss) on available-for-sale securities	(490)			(490)
Net loss	(6,567)					(6,567)
Balance at Dec. 31, 2009	71,833	$ 287	242,259	43		(170,756)
Balance (in shares) at Dec. 31, 2009		22,672,427
Increase (Decrease) in Stockholders' Equity
Issuance of common stock	13,830	$ 50	13,780
Issuance of common stock (in shares)		4,946,525
Stock issued from collaboration agreement	28,083	$ 69	28,014
Stock issued from collaboration agreement (in shares)		6,866,245
Stock issued from exercise of stock options, net	9		9
Stock issued from exercise of stock options, net (in shares)		23,735
Stock-based compensation	6,186		6,186
Comprehensive (Loss)/ Income:
Unrealized holding gain (loss) on available-for-sale securities	(71)			(71)
Net loss	(54,936)					(54,936)
Balance at Dec. 31, 2010	64,934	$ 406	290,248	(28)		(225,692)
Balance (in shares) at Dec. 31, 2010		34,508,932
Increase (Decrease) in Stockholders' Equity
Stock issued from exercise of stock options, net	360	$ 1	359
Stock issued from exercise of stock options, net (in shares)		145,274
Stock-based compensation	8,678		8,678
Comprehensive (Loss)/ Income:
Unrealized holding gain (loss) on available-for-sale securities	32			32
Net loss	(44,412)					(44,412)
Balance at Dec. 31, 2011	$ 29,592	$ 407	299,285	4		(270,104)
Balance (in shares) at Dec. 31, 2011	34,654,206	34,654,206
Increase (Decrease) in Stockholders' Equity
Issuance of common stock	$ 62,055	$ 115	61,940
Issuance of common stock (in shares)		11,500,000
Stock issued from collaboration agreement	18,140	$ 29	18,111
Stock issued from collaboration agreement (in shares)		2,949,581
Stock issued from exercise of stock options, net	1,630	$ 4	1,626
Stock issued from exercise of stock options, net (in shares)		436,952
Stock issued from exercise of warrants	387	$ 1	386
Stock issued from exercise of warrants (in shares)		90,933
Stock-based compensation	6,191		6,191
Comprehensive (Loss)/ Income:
Unrealized holding gain (loss) on available-for-sale securities	10			10
Net loss	(48,785)					(48,785)
Balance at Dec. 31, 2012	$ 69,220	$ 556	$ 387,539	$ 14		$ (318,889)
Balance (in shares) at Dec. 31, 2012	49,631,672	49,631,672

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended			131 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012
Operating activities
Net loss	$ (48,785)	$ (44,412)	$ (54,936)	$ (318,889)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash interest expense				525
Depreciation and amortization	1,705	1,585	2,058	11,768
Amortization of non-cash compensation				522
Stock-based compensation	6,191	8,679	6,186	41,929
Non-cash charge for stock based compensation issued to consultants				853
Change in fair value of warrant liability	(653)	(2,764)	1,410	(1,553)
Loss on disposal of asset	28		121	388
Stock-based license payment				1,220
Impairment of leasehold improvements				1,030
Non-cash charge for in process research and development				418
Beneficial conversion feature related to bridge financing				135
Changes in operating assets and liabilities:
Receivable due from GSK	1,818	(5,043)		(3,225)
Prepaid expenses and other current assets	3,633	(3,667)	26	(2,270)
Other non-current assets	267	(442)	218	(466)
Account payable and accrued expenses	(863)	1,418	(1,345)	8,845
Deferred reimbursements	2,915	(4,776)	32,279	30,418
Net cash used in operating activities	(33,744)	(49,422)	(13,983)	(228,352)
Investing activities
Sale and redemption of marketable securities	83,352	98,474	94,602	755,442
Purchases of marketable securities	(118,459)	(50,602)	(113,660)	(820,695)
Purchases of property and equipment	(4,324)	(1,420)	(384)	(18,213)
Net cash (used in)/provided by investing activities	(39,431)	46,452	(19,442)	(83,466)
Financing activities
Proceeds from the issuance of preferred stock, net of issuance costs				143,022
Proceeds from issuance of common stock, net of issuance costs	80,195		45,214	193,441
Proceeds from the issuance of convertible notes				5,000
Payments of capital lease obligations		(40)	(313)	(5,587)
Payments of secured loan agreement	(1,342)	(1,253)	(1,252)	(4,056)
Proceeds from exercise of stock options	1,630	359	9	3,341
Proceeds from exercise of warrants (common and preferred)				264
Proceeds from capital asset financing arrangement				5,611
Proceeds from secured loan agreement	995			4,753
Net cash provided by/(used in) financing activities	81,478	(934)	43,658	345,789
Net increase/(decrease) in cash and cash equivalents	8,303	(3,904)	10,233	33,971
Cash and cash equivalents at beginning of year/period	25,668	29,572	19,339	0
Cash and cash equivalents at end of year/period	33,971	25,668	29,572	33,971
Supplemental disclosures of cash flow information
Cash paid during the period for interest	84	$ 149	$ 280	2,117
Non-cash activities
Conversion of warrants to common stock	$ 386			386
Conversion of notes payable to Series B redeemable convertible				5,000
Conversion of preferred stock to common stock				148,951
Accretion of redeemable convertible preferred stock				802
Beneficial conversion feature related to issuance of the additional issuance of Series C redeemable convertible preferred stock				$ 19,424

Description of Business	12 Months Ended
Description of Business	Dec. 31, 2012
Description of Business
Description of Business	1. Description of Business *Corporate Information, Status of Operations, and Management Plans* Amicus Therapeutics, Inc. (the Company) was incorporated on February 4, 2002 in Delaware and is a biopharmaceutical company focused on the discovery, development and commercialization of orally-administered, small molecule drugs known as pharmacological chaperones, a novel, first-in-class approach to treating a broad range of diseases including lysosomal storage disorders and diseases of neurodegeneration. The Company's activities since inception have consisted principally of raising capital, establishing facilities, and performing research and development. Accordingly, the Company is considered to be in the development stage. On July 17, 2012, the Company entered into an Amended and Restated License and Expanded Collaboration Agreement (the "Expanded Collaboration Agreement") with an affiliate of GlaxoSmithKline PLC (GSK) pursuant to which the Company and GSK will continue to develop and commercialize migalastat HCl, currently in Phase 3 development for the treatment of Fabry disease. The Expanded Collaboration Agreement amends and replaces in its entirety the License and Collaboration Agreement entered into between the Company and GSK on October 28, 2010 (the "Original Collaboration Agreement") for the development and commercialization of migalastat HCl. Under the terms of the Expanded Collaboration Agreement, the Company and GSK will co-develop all formulations of migalastat HCl for Fabry disease, including the development of migalastat HCl co-formulated with an investigational enzyme replacement therapy (ERT) for Fabry disease (the "Co-formulated Product") in collaboration with another GSK collaborator JCR Pharmaceutical Co., Ltd. The Company will commercialize all migalastat HCl products for Fabry disease in the United States while GSK will commercialize all such products in the rest of the world. GSK is eligible to receive U.S. regulatory approval milestones totaling $20 million for migalastat HCl monotherapy and migalastat HCl for co-administration with ERT, and additional regulatory approval and product launch milestone payments totaling up to $35 million within seven years following the launch of the Co-formulated Product. The Company will also be responsible for certain pass-through milestone payments and single-digit royalties on the net U.S. sales of the Co-formulated Product that GSK must pay to a third party. In addition, the Company is no longer eligible to receive any milestones or royalties it would have been eligible to receive under the Original Collaboration Agreement other than a $3.5 million clinical development milestone achieved in the second quarter of 2012 and paid by GSK to Amicus in the third quarter of 2012. The Company and GSK will continue to jointly fund development costs for all formulations of migalastat HCl in accordance with agreed upon development plans pursuant to which the Company and GSK funded 25% and 75% of such costs, respectively, for the monotherapy and co-administration programs during 2012 and 40% and 60%, respectively in 2013 and beyond. Effective upon entry into the Expanded Collaboration Agreement, costs for the development of the Co-formulated Product are also funded 40% and 60% between Amicus and GSK, respectively. Additionally, simultaneous with entry into the Expanded Collaboration Agreement, the Company and GSK entered into a Stock Purchase Agreement (the "SPA") pursuant to which GSK purchased approximately 2.9 million shares of Amicus common stock at a price of $6.30 per share. The total value of this equity investment to the Company is approximately $18.6 million. As of December 31, 2012, GSK's ownership position in the Company is 19.8%. GSK purchased approximately 6.9 million shares for an aggregate investment of approximately $31 million in connection with entry into the Original Collaboration Agreement in 2010. For further information, see "— Note 12. Collaborative Agreements." The Company had an accumulated deficit of approximately $318.9 million at December 31, 2012 and anticipates incurring losses through the year 2013 and beyond. The Company has not yet generated commercial sales revenue and has been able to fund its operating losses to date through the sale of its redeemable convertible preferred stock, issuance of convertible notes, net proceeds from its initial public offering (IPO) and subsequent stock offerings, payments from partners during the terms of the collaboration agreements and other financing arrangements. In March 2010, the Company sold 4.95 million shares of its common stock and warrants to purchase 1.9 million shares of common stock in a registered direct offering to a select group of institutional investors for net proceeds of $17.1 million. In October 2010, the Company sold 6.87 million shares of its common stock as part of the Original License and Collaboration Agreement with GSK for proceeds of $31 million. In March 2012, the Company sold 11.5 million shares of its common stock in a stock offering for net proceeds of $62.0 million. In July 2012, the Company sold 2.9 million shares of its common stock as part of the Expanded Collaboration Agreement with GSK for proceeds of $18.6 million. The Company believes that its existing cash and cash equivalents and short-term investments will be sufficient to cover its cash flow requirements for 2013.

- Definition

The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Number 94-6
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Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
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Reference 15: http://www.xbrl.org/2003/role/presentationRef
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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+ Details

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2012

Summary of Significant Accounting Policies

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying consolidated financial statements have been prepared in accordance with U.S. GAAP and include all adjustments necessary for the fair presentation of the Company's financial position for the periods presented.

Consolidation

The financial statements include the accounts of Amicus Therapeutics, Inc. and its wholly owned subsidiary, Amicus Therapeutics UK Limited. All significant intercompany transactions and balances are eliminated in consolidation. This subsidiary is not material to the overall financial statements of the Company.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates.

Cash, Money Market Funds, and Marketable Securities

The Company considers all highly liquid investments purchased with a maturity of three months or less at the date of acquisition, to be cash equivalents.

Marketable securities consist of fixed income investments with a maturity of greater than three months and other highly liquid investments that can be readily purchased or sold using established markets. These investments are classified as available-for-sale and are reported at fair value on the Company's balance sheet. Unrealized holding gains and losses are reported within comprehensive income/(loss) in the statements of comprehensive loss. Fair value is based on available market information including quoted market prices, broker or dealer quotations or other observable inputs. See "— Note 3. Cash, Money Market Funds and Marketable Securities" for a summary of available-for-sale securities as of December 31, 2012 and 2011.

Concentration of Credit Risk

The Company's financial instruments that are exposed to concentration of credit risk consist primarily of cash and cash equivalents and marketable securities. The Company maintains its cash and cash equivalents in bank accounts, which, at times, exceed federally insured limits. The Company invests its marketable securities in high-quality commercial financial instruments. The Company has not recognized any losses from credit risks on such accounts during any of the periods presented. The Company believes it is not exposed to significant credit risk on cash and cash equivalents or its marketable securities.

Property and Equipment

Property and equipment are stated at cost, less accumulated depreciation and amortization. Depreciation is calculated over the estimated useful lives of the respective assets, which range from three to five years, or the lesser of the related initial term of the lease or useful life for leasehold improvements. Assets under capital leases are amortized over the terms of the related leases or their estimated useful lives, whichever is shorter.

The initial cost of property and equipment consists of its purchase price and any directly attributable costs of bringing the asset to its working condition and location for its intended use. Expenditures incurred after the fixed assets have been put into operation, such as repairs and maintenance, are charged to income in the period in which the costs are incurred. Major replacements, improvements and additions are capitalized in accordance with Company policy.

Impairment of Long-Lived Assets

The Company performs a review of long-lived assets for impairment when events or changes in circumstances indicate the carrying value of such assets may not be recoverable. If an indication of impairment is present, the Company compares the estimated undiscounted future cash flows to be generated by the asset to its carrying amount. If the undiscounted future cash flows are less than the carrying amount of the asset, the Company records an impairment loss equal to the excess of the asset's carrying amount over its fair value. The fair value is determined based on valuation techniques such as a comparison to fair values of similar assets or using a discounted cash flow analysis. There were no impairment charges recognized during the years ended December 31, 2010, 2011 and 2012.

Revenue Recognition

The Company recognizes revenue when amounts are realized or realizable and earned. Revenue is considered realizable and earned when the following criteria are met: (1) persuasive evidence of an arrangement exists; (2) delivery has occurred or services have been rendered; (3) the price is fixed or determinable; and (4) collection of the amounts due are reasonably assured.

In multiple element arrangements, revenue is allocated to each separate unit of accounting and each deliverable in an arrangement is evaluated to determine whether it represents separate units of accounting. A deliverable constitutes a separate unit of accounting when it has standalone value and there is no general right of return for the delivered elements. In instances when the aforementioned criteria are not met, the deliverable is combined with the undelivered elements and the allocation of the arrangement consideration and revenue recognition is determined for the combined unit as a single unit of accounting. Allocation of the consideration is determined at arrangement inception on the basis of each unit's relative selling price. In instances where there is determined to be a single unit of accounting, the total consideration is applied as revenue for the single unit of accounting and is recognized over the period of inception through the date where the last deliverable within the single unit of accounting is expected to be delivered.

The Company's current revenue recognition policies, which were applied in fiscal 2010, provide that, when a collaboration arrangement contains multiple deliverables, such as license and research and development services, the Company allocates revenue to each separate unit of accounting based on a selling price hierarchy. The selling price hierarchy for a deliverable is based on (i) its vendor specific objective evidence (VSOE) if available, (ii) third party evidence (TPE) if VSOE is not available, or (iii) best estimated selling price (BESP) if neither VSOE nor TPE is available. The Company would establish the VSOE of selling price using the price charged for a deliverable when sold separately. The TPE of selling price would be established by evaluating largely similar and interchangeable competitor products or services in standalone sales to similarly situated customers. The BESP would be established considering internal factors such as an internal pricing analysis or an income approach using a discounted cash flow model.

The Company also considers the impact of potential future payments it makes in its role as a vendor to its customers and evaluates if these potential future payments could be a reduction of revenue from that customer. If the potential future payments to the customer are:

•

a payment for an identifiable benefit; and

•

the identifiable benefit is separable from the existing relationship between the Company and its customer; and

•

the identifiable benefit can be obtained from a party other than the customer; and

•

the Company can reasonably estimate the fair value of the identifiable benefit

then the payments are accounted for separate from the revenue received from that customer. If, however, all these criteria are not satisfied, then the payments are treated as a reduction of revenue from that customer.

If the Company determines that any potential future payments to its customers are to be considered as a reduction of revenue, it must evaluate if the total amount of revenue to be received under the arrangement is fixed and determinable. If the total amount of revenue is not fixed and determinable due to the uncertain nature of the potential future payments to the customer, then any customer payments cannot be recognized as revenue until the total arrangement consideration becomes fixed and determinable.

The reimbursements for research and development costs under collaboration agreements that meet the criteria for revenue recognition are included in Research Revenue and the costs associated with these reimbursable amounts are included in research and development expenses.

In order to determine the revenue recognition for contingent milestones, the Company evaluates the contingent milestones using the criteria as provided by the Financial Accounting Standards Boards (FASB) guidance on the milestone method of revenue recognition at the inception of a collaboration agreement. The criteria requires that (i) the Company determines if the milestone is commensurate with either its performance to achieve the milestone or the enhancement of value resulting from the Company's activities to achieve the milestone, (ii) the milestone be related to past performance, and (iii) the milestone be reasonable relative to all deliverable and payment terms of the collaboration arrangement. If these criteria are met then the contingent milestones can be considered as substantive milestones and will be recognized as revenue in the period that the milestone is achieved.

Fair Value Measurements

The Company records certain asset and liability balances under the fair value measurements as defined by the FASB guidance. Current FASB fair value guidance emphasizes that fair value is a market-based measurement, not an entity-specific measurement. Therefore, a fair value measurement should be determined based on the assumptions that market participants would use in pricing the asset or liability. As a basis for considering market participant assumptions in fair value measurements, current FASB guidance establishes a fair value hierarchy that distinguishes between market participant assumptions based on market data obtained from sources independent of the reporting entity (observable inputs that are classified within Levels 1 and 2 of the hierarchy) and the reporting entity's own assumptions that market participants assumptions would use in pricing assets or liabilities (unobservable inputs classified within Level 3 of the hierarchy).

Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access at measurement date. Level 2 inputs are inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs may include quoted prices for similar assets and liabilities in active markets, as well as inputs that are observable for the asset or liability (other than quoted prices), such as interest rates, foreign exchange rates, and yield curves that are observable at commonly quoted intervals. Level 3 inputs are unobservable inputs for the asset or liability, which are typically based on an entity's own assumptions, as there is little, if any, related market activity. In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. The Company's assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability.

Research and Development Costs

Research and development costs are expensed as incurred. Research and development expense consists primarily of costs related to personnel, including salaries and other personnel-related expenses, consulting fees and the cost of facilities and support services used in drug development. Assets acquired that are used for research and development and have no future alternative use are expensed as in-process research and development.

Interest Income and Interest Expense

Interest income consists of interest earned on the Company's cash and cash equivalents and marketable securities. Interest expense consists of interest incurred on capital leases and secured debt.

Other Income and Expenses

Other income includes funds received from the U.S. Treasury Department in 2010 and 2011 for the Qualified Therapeutic Discovery Projects tax credit and grant program and the gain on sale of certain fixed assets in 2012. Other expenses include costs directly attributable to a planned offering of the Company's securities that were subsequently withdrawn during 2006 and the losses on the disposal of certain fixed assets.

Income Taxes

The Company accounts for income taxes under the liability method. Under this method deferred income tax liabilities and assets are determined based on the difference between the financial statement carrying amounts and tax basis of assets and liabilities and for operating losses and tax credit carry forwards, using enacted tax rates in effect in the years in which the differences are expected to reverse. A valuation allowance is recorded if it is "more likely than not" that a portion or all of a deferred tax asset will not be realized.

Other Comprehensive Income/ (Loss)

Components of other comprehensive income/ (loss) include unrealized gains and losses on available-for-sale securities and are included in the statements of comprehensive loss.

Leases

In the ordinary course of business, the Company enters into lease agreements for office space as well as leases for certain property and equipment. The leases have varying terms and expirations and have provisions to extend or renew the lease agreement, among other terms and conditions, as negotiated. Once the agreement is executed, the lease is assessed to determine whether the lease qualifies as a capital or operating lease.

When a non-cancelable operating lease includes any fixed escalation clauses and lease incentives for rent holidays or build-out contributions, rent expense is recognized on a straight-line basis over the initial term of the lease. The excess between the average rental amount charged to expense and amounts payable under the lease is recorded in accrued expenses.

Stock-Based Compensation

At December 31, 2012, the Company had three stock-based employee compensation plans, which are described more fully in "— Note 6. Stockholders' Equity." The Company applies the fair value method of measuring stock-based compensation, which requires a public entity to measure the cost of employee services received in exchange for an award of equity instruments based on the grant-date fair value of the award.

Basic and Diluted Net Loss Attributable to Common Stockholders per Common Share

The Company calculates net loss per share as a measurement of the Company's performance while giving effect to all dilutive potential common shares that were outstanding during the reporting period. The Company had a net loss for all periods presented; accordingly, the inclusion of common stock options and warrants would be anti-dilutive. Therefore, the weighted average shares used to calculate both basic and diluted earnings per share are the same.

The following table provides a reconciliation of the numerator and denominator used in computing basic and diluted net loss attributable to common stockholders per common share (in thousands except share amounts):

	Years Ended December 31,

	2010			2011			2012
Historical
Numerator:
Net loss attributable to common stockholders	$	(54,936	)	$	(44,412	)	$	(48,785	)

Denominator:
Weighted average common shares outstanding — basic and diluted		27,734,797			34,569,642			45,565,217

Dilutive common stock equivalents would include the dilutive effect of common stock options and warrants for common stock equivalents. Potentially dilutive common stock equivalents totaled approximately 7.0 million, 8.5 million and 9.4 million for the years ended December 31, 2010, 2011 and 2012, respectively. Potentially dilutive common stock equivalents were excluded from the diluted earnings per share denominator for all periods because of their anti-dilutive effect.

Dividends

The Company has not paid cash dividends on its capital stock to date. The Company currently intends to retain its future earnings, if any, to fund the development and growth of the business and does not foresee payment of a dividend in any upcoming fiscal period.

Recent Accounting Pronouncements

In February 2013, the Financial Accounting Standards Board (the FASB) amended its guidance to require an entity to present the effect of certain significant reclassifications out of accumulated other comprehensive income on the respective line items in net income. The new accounting guidance does not change the items that must be reported in other comprehensive income or when an item of other comprehensive income must be reclassified to net income. The guidance is effective prospectively for fiscal years beginning after December 15, 2012 and the Company will be required to adopt these new provisions no later than the quarter beginning January 1, 2013. As the guidance requires additional presentation only, there will be no impact to the Company's consolidated results of operations or financial position.

In June 2011, the FASB amended its guidance on the presentation of comprehensive income in financial statements to improve the comparability, consistency and transparency of financial reporting and to increase the prominence of items that are recorded in other comprehensive income. The new accounting guidance requires entities to report components of comprehensive income in either (1) a continuous statement of comprehensive income or (2) two separate but consecutive statements. The provisions of this guidance are effective for fiscal years, and interim periods within those years, beginning after December 15, 2011. Other than a change in presentation, the implementation of this accounting pronouncement did not have a material impact on the Company's financial statements.

In May 2011, the FASB amended the FASB Accounting Standards Codification to converge the fair value measurement guidance in U.S. GAAP and International Financial Reporting Standards. Some of the amendments clarify the application of existing fair value measurement requirements, while other amendments change particular principles in fair value measurement guidance. In addition, the amendments require additional fair value disclosures. The amendments are effective for fiscal year 2012 and should be applied prospectively. The provisions of the amendments did not have a material impact on the Company's consolidated results of operations or financial position.

Segment Information

The Company currently operates in one business segment focusing on the development and commercialization of small molecule, orally administered therapies to treat a range of human genetic diseases. The Company is not organized by market and is managed and operated as one business. A single management team reports to the chief operating decision maker who comprehensively manages the entire business. The Company does not operate any separate lines of business or separate business entities with respect to its products. Accordingly, the Company does not accumulate discrete financial information with respect to separate service lines and does not have separately reportable segments.

Cash, Money Market Funds and Marketable Securities

12 Months Ended

Dec. 31, 2012

Cash, Money Market Funds, and Marketable Securities

Cash, Money Market Funds, and Marketable Securities

3. Cash, Money Market Funds and Marketable Securities

As of December 31, 2012, the Company held $34.0 million in cash and cash equivalents and $65.2 million of available-for-sale securities which are reported at fair value on the Company's balance sheet. Unrealized holding gains and losses are reported within comprehensive income/(loss) in the statements of comprehensive loss. If a decline in the fair value of a marketable security below the Company's cost basis is determined to be other than temporary, such marketable security is written down to its estimated fair value as a new cost basis and the amount of the write-down is included in earnings as an impairment charge. To date, only temporary impairment adjustments have been recorded.

Consistent with the Company's investment policy, the Company does not use derivative financial instruments in its investment portfolio. The Company regularly invests excess operating cash in deposits with major financial institutions, money market funds, notes issued by the U.S. government, as well as fixed income investments and U.S. bond funds both of which can be readily purchased and sold using established markets. The Company believes that the market risk arising from its holdings of these financial instruments is mitigated as many of these securities are either government backed or of the highest credit rating.

Cash and available for sale securities consisted of the following as of December 31, 2011 and December 31, 2012 (in thousands):

	As of December 31, 2011

	Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash balances	$	25,668	$	—	$	—		$	25,668
U.S. government agency securities		2,000		—		—			2,000
Corporate debt securities		13,943		—		(8	)		13,935
Commercial paper		13,737		12		—			13,749
Certificate of deposit		350		—		—			350

	$	55,698	$	12	$	(8	)	$	55,702

Included in cash and cash equivalents	$	25,668	$	—	$	—		$	25,668
Included in marketable securities		30,030		12		(8	)		30,034

Total cash and marketable securities	$	55,698	$	12	$	(8	)	$	55,702

	As of December 31, 2012

	Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash balances	$	33,971	$	—	$	—		$	33,971
Corporate debt securities		42,503		5		(11	)		42,497
Commercial paper		19,725		19		—			19,744
Certificate of deposit		2,909		1		—			2,910

	$	99,108	$	25	$	(11	)	$	99,122

Included in cash and cash equivalents	$	33,971	$	—	$	—		$	33,971
Included in marketable securities		65,137		25		(11	)		65,151

Total cash and marketable securities	$	99,108	$	25	$	(11	)	$	99,122

All of the Company's available for sale investments as of December 31, 2011 and December 31, 2012 are due in one year or less.

Unrealized gains and losses are reported as a component of other comprehensive gain/(loss) in the statements of comprehensive loss. For the year ended December 31, 2011 and 2012, unrealized holding gains of $32 thousand and $10 thousand respectively, were included in the statements of comprehensive loss.

For the years ended December 31, 2011 and 2012, there were no realized gains or losses. The cost of securities sold is based on the specific identification method.

Unrealized loss positions in the available for sale securities as of December 31, 2011 and December 31, 2012 reflect temporary impairments that have been in a loss position for less than twelve months and as such are recognized in other comprehensive gain/(loss). The fair value of these available for sale securities in unrealized loss positions was $13.2 million and $33.1 million as of December 31, 2011 and December 31, 2012, respectively.

Property and Equipment

12 Months Ended

Dec. 31, 2012

Property and Equipment

Property and Equipment

4. Property and Equipment

Property and equipment consist of the following (in thousands):

	December 31,

	2011			2012
Property and equipment consist of the following:
Computer equipment	$	2,556		$	3,399
Computer software		641			849
Research equipment		4,986			5,807
Furniture and fixtures		1,040			1,544
Leasehold improvements		2,722			1,931

		11,945			13,530
Less accumulated depreciation and amortization		(9,507	)		(8,501	)

	$	2,438		$	5,029

Depreciation and amortization expense relating to the capital lease obligations was $1.7 million and $6.9 million for the year ended December 31, 2010 and for the Period February 4, 2002 (inception) to December 31, 2012, respectively. There were no capital lease obligations outstanding as of December 31, 2011 and December 31, 2012.

- Definition

The entire disclosure for long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software. This disclosure may include property plant and equipment accounting policies and methodology, a schedule of property, plant and equipment gross, additions, deletions, transfers and other changes, depreciation, depletion and amortization expense, net, accumulated depreciation, depletion and amortization expense and useful lives, income statement disclosures, assets held for sale and public utility disclosures.

+ References + Details

Accounts Payable and Accrued Expenses

12 Months Ended

Dec. 31, 2012

Accounts Payable and Accrued Expenses

Accounts Payable and Accrued Expenses

5. Accounts Payable and Accrued Expenses

Accrued expenses consist of the following (in thousands):

	December 31,

	2011		2012
Accounts payable	$	2,576	$	2,115
Accrued professional fees		215		409
Accrued contract manufacturing & contract research costs		3,489		1,743
Accrued compensation and benefits		3,162		4,229
Accrued facility costs		27		167
Accrued other		201		182
Accrued facilities consolidation		38		—

	$	9,708	$	8,845

Stockholders' Equity

12 Months Ended

Dec. 31, 2012

Stockholders' Equity

Stockholders' Equity

6. Stockholders' Equity

Common Stock and Warrants

As of December 31, 2012, the Company was authorized to issue 125,000,000 shares of common stock. Dividends on common stock will be paid when, and if declared by the board of directors. Each holder of common stock is entitled to vote on all matters and is entitled to one vote for each share held.

During 2012, there were approximately 0.5 million warrants exercised in a cashless transaction and the resulting fair value of the warrant liability at December 31, 2012 was $0.9 million.

In July 2012, Amicus and GSK entered into the SPA pursuant to which GSK purchased 2.9 million unregistered shares of Amicus common stock at a price of $6.30 per share. The total purchase price for these shares was $18.6 million. The Company received all proceeds from the sale of such shares on July 26, 2012. As of December 31, 2012, GSK had a 19.8% ownership position in the Company.

In March 2012, the Company sold 11.5 million shares of its common stock at a public offering price of $5.70 through a Registration Statement on Form S-3 that was declared effective by the SEC on May 27, 2009. The aggregate offering proceeds were $65.6 million.

In October 2010, GSK purchased approximately 6.9 million shares of the Company's common stock at $4.56 per share, in connection with the Original Collaboration Agreement. The total value of this equity investment was approximately $31 million.

In March 2010, the Company sold 4.9 million shares of its common stock and warrants to purchase 1.9 million shares of common stock in a registered direct offering to a selected group of institutional investors through a Registration Statement on Form S-3 that was declared effective by the SEC on May 27, 2009. The shares of common stock and warrants were sold in units consisting of one share of common stock and one warrant to purchase 0.375 shares of common stock at a price of $3.74 per unit. The warrants have a term of four years and are exercisable any time on or after the six month anniversary of the date they were issued, at an exercise price of $4.43 per share. The aggregate offering proceeds were $18.5 million. There were approximately 1.4 million warrants outstanding at December 31, 2012.

Stock Option Plans

In April 2002, the Company's Board of Directors and shareholders approved the Company's 2002 Stock Option Plan (the 2002 Plan). In May 2007, the Company's Board of Directors and shareholders approved the Company's 2007 Stock Option Plan (the 2007 Plan) and 2007 Director Option Plan (the 2007 Director Plan). In June 2010, the Company's Board of Directors and shareholders approved amendments to the 2007 Plan and the 2007 Director Plan. Both the 2002 Plan and 2007 Plan provide for the granting of restricted stock and options to purchase common stock in the Company to employees, advisors and consultants at a price to be determined by the Company's board of directors. The 2002 Plan and the 2007 Plan are intended to encourage ownership of stock by employees and consultants of the Company and to provide additional incentives for them to promote the success of the Company's business. The Options may be incentive stock options (ISOs) or non-statutory stock options (NSOs). Under the provisions of each plan, no option will have a term in excess of 10 years. The 2007 Director Plan is intended to promote the recruiting and retention of highly qualified eligible directors and strengthen the commonality of interest between directors and stockholders by encouraging ownership of common stock of the Company. The options granted under the 2007 Director Plan are NSOs and under the provisions of this plan, no option will have a term in excess of 10 years.

The Board of Directors, or its committee, is responsible for determining the individuals to be granted options, the number of options each individual will receive, the option price per share, and the exercise period of each option. Options granted pursuant to both the 2002 Plan and the 2007 Plan generally vest 25% on the first year anniversary date of grant plus an additional 1/48th for each month thereafter and may be exercised in whole or in part for 100% of the shares vested at any time after the date of grant. Options under the 2007 Director Plan may be granted to new directors upon joining the Board and vest in the same manner as options under the 2002 and 2007 Plans. In addition, options are automatically granted to all directors at each annual meeting of stockholders and vest on the date of the annual meeting of stockholders of the Company in the year following the year during which the options were granted.

As of December 31, 2012, there were no shares reserved for issuance under the 2002 Plan. The Company has reserved up to 3,277,079 shares for issuance under the 2007 Plan and the 2007 Director Plan.

The Company recognized stock-based compensation expense of $6.2 million, $8.7 million and $6.2 million in 2010, 2011 and 2012, respectively. Additional stock option compensation expense of $2.7 million was recognized in 2011 due to a change in the terms of the Chief Executive Officer's stock options resulting from his resignation and subsequent reappointment to the Chief Executive Officer position. The following table summarizes information related to stock compensation expense recognized in the statements of operations (in millions):

	Years Ended December 31,

	2010		2011		2012
Stock compensation expense recognized in:
Research and development expense	$	2.6	$	2.9	$	3.6
General and administrative expense		3.6		5.8		2.6

Total stock compensation expense	$	6.2	$	8.7	$	6.2

The Company adopted the fair value method of measuring stock-based compensation, which requires a public entity to measure the cost of employee services received in exchange for an award of equity instruments based upon the grant-date fair value of the award. The Company chose the "straight-line" attribution method for allocating compensation costs and recognized the fair value of each stock option on a straight-line basis over the vesting period of the related awards.

The Company uses the Black-Scholes option pricing model when estimating the fair value for stock-based awards. Use of a valuation model requires management to make certain assumptions with respect to selected model inputs. Expected volatility was calculated based on a blended weighted average of historical information of the Company's stock and the weighted average of historical information of similar public entities for which historical information was available. The Company will continue to use a blended weighted average approach using its own historical volatility and other similar public entity volatility information until the Company's historical volatility is relevant to measure expected volatility for future option grants. The average expected life was determined using the "simplified" method of estimating the expected exercise term which is the mid-point between the vesting date and the end of the contractual term. As the Company's stock price volatility has been over 75% and it has experienced significant business transactions (Shire and GSK collaborations), the Company does not have sufficient reliable exercise data in order to justify a change in the use of the "simplified" method of estimating the expected exercise term of employee stock option grants. The risk-free interest rate is based on U.S. Treasury, zero-coupon issues with a remaining term equal to the expected life assumed at the date of grant. Forfeitures are estimated based on voluntary termination behavior, as well as a historical analysis of actual option forfeitures.

The weighted average assumptions used in the Black-Scholes option pricing model are as follows:

	Years Ended December 31,

	2010			2011			2012
Expected stock price volatility		80.5	%		78.8	%		77.2	%
Risk free interest rate		2.4	%		2.0	%		0.8	%
Expected life of options (years)		6.25			6.25			6.25
Expected annual dividend per share	$	0.00		$	0.00		$	0.00

The weighted-average grant-date fair value per share of options granted during 2010, 2011 and 2012 were $2.09, $4.11 and $3.31, respectively.

The following table summarizes information about stock options outstanding:

	Number of Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value

	(in thousands)						(in thousands)
Options outstanding, December 31, 2009		4,818.9		$	8.01
Granted		788.7		$	2.96
Exercised		(25.9	)	$	0.64
Forfeited		(477.6	)	$	7.93

Options outstanding, December 31, 2010		5,104.1		$	7.27
Granted		2,217.0		$	5.92
Exercised		(108.5	)	$	3.88
Forfeited		(559.1	)	$	7.34

Options outstanding, December 31, 2011		6,653.5		$	6.87
Granted		2,846.6		$	5.34
Exercised		(437.0	)	$	3.73
Forfeited		(1,088.9	)	$	7.95

Options outstanding, December 31, 2012		7,974.2		$	6.35	7.4 years	$	46.0

Vested and unvested expected to vest, December 31, 2012		7,437.4		$	6.41	7.3 years	$	46.0
Exercisable at December 31, 2012		3,955.7		$	7.41	6.0 years	$	46.0

The aggregate intrinsic value of options exercised during the years ended December 31, 2010, 2011 and 2012, was $0.1 million, $0.3 million and $0.9 million, respectively. As of December 31, 2012, the total unrecognized compensation cost related to non-vested stock options granted was $10.4 million and is expected to be recognized over a weighted average period of 2.6 years. Cash proceeds from stock options exercised during the years ended December 31, 2010, 2011 and 2012 were $0.02 million, $0.4 million and $1.6 million respectively.

Restricted Stock Awards — Restricted stock awards are granted subject to certain restrictions, including in some cases service conditions (restricted stock). The grant-date fair value of restricted stock awards, which has been determined based upon the market value of the Company's shares on the grant date, is expensed over the vesting period.

The following table summarizes information on the Company's restricted stock:

	Restricted Stock

	Number of Shares			Weighted Average Grant Date Fair Value
	(in thousands)
Unvested at December 31, 2010		—		$	—
Granted		50.0		$	7.21
Vested		(50.0	)	$	7.21
Forfeited		—		$	—

Unvested at December 31, 2011		—		$	—
Granted		—		$	—
Vested		—		$	—
Forfeited		—		$	—

Unvested at December 31, 2012		—		$	—

Upon vesting in 2011, there were 13,225 shares surrendered to fund minimum statutory tax withholding requirements. There were no restricted stock awards in 2012. As of December 31, 2012, there was no unrecognized compensation cost related to unvested restricted stock awards. The total fair value of restricted stock awards which vested during 2011 was $0.4 million.

- Definition

The entire disclosure for shareholders' equity, comprised of portions attributable to the parent entity and noncontrolling interest, if any, including other comprehensive income (as applicable). Including, but not limited to: (1) balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings; (2) accumulated balance for each classification of other comprehensive income and total amount of comprehensive income; (3) amount and nature of changes in separate accounts, including the number of shares authorized and outstanding, number of shares issued upon exercise and conversion, and for other comprehensive income, the adjustments for reclassifications to net income; (4) rights and privileges of each class of stock authorized; (5) basis of treasury stock, if other than cost, and amounts paid and accounting treatment for treasury stock purchased significantly in excess of market; (6) dividends paid or payable per share and in the aggregate for each class of stock for each period presented; (7) dividend restrictions and accumulated preferred dividends in arrears (in aggregate and per share amount); (8) retained earnings appropriations or restrictions, such as dividend restrictions; (9) impact of change in accounting principle, initial adoption of new accounting principle and correction of an error in previously issued financial statements; (10) shares held in trust for Employee Stock Ownership Plan (ESOP); (11) deferred compensation related to issuance of capital stock; (12) note received for issuance of stock; (13) unamortized discount on shares; (14) description, terms, and number of warrants or rights outstanding; (15) shares under subscription and subscription receivables, effective date of new retained earnings after quasi-reorganization and deficit eliminated by quasi-reorganization and, for a period of at least ten years after the effective date, the point in time from which the new retained dates; and (16) retroactive effective of subsequent change in capital structure.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
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-Subparagraph (SX 210.4-08.(d),(e))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

Reference 9: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Preferred Stock
-URI http://asc.fasb.org/extlink&oid=6521494

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 43
-Section B
-Paragraph 7, 11A
-Chapter 1
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 16: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 17: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
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-Number 210
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Reference 18: http://www.xbrl.org/2003/role/presentationRef
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Reference 19: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
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Reference 20: http://www.xbrl.org/2003/role/presentationRef
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Reference 21: http://www.xbrl.org/2003/role/presentationRef
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Reference 22: http://www.xbrl.org/2003/role/presentationRef
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 23: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
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-Article 3

+ Details

Assets and Liabilities Measured at Fair Value

12 Months Ended

Dec. 31, 2012

Assets and Liabilities Measured at Fair Value

Assets and Liabilities Measured at Fair Value

7. Assets and Liabilities Measured at Fair Value

The Company's financial assets and liabilities are measured at fair value and classified within the fair value hierarchy which is defined as follows:

- Level 1 — Quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date.
  
  Level 2 — Inputs other than quoted prices in active markets that are observable for the asset or liability, either directly or indirectly.
  
  Level 3 — Inputs that are unobservable for the asset or liability.
Cash, Money Market Funds and Marketable Securities

The Company classifies its cash and money market funds within the fair value hierarchy as Level 1 as these assets are valued using quoted prices in active market for identical assets at the measurement date. The Company considers its investments in marketable securities as available for sale and classifies these assets within the fair value hierarchy as Level 2 primarily utilizing broker quotes in a non-active market for valuation of these securities. No changes in valuation techniques or inputs occurred during the year ended December 31, 2012. No transfers of assets between Level 1 and Level 2 of the fair value measurement hierarchy occurred during the year ended December 31, 2012.

Secured Debt

As disclosed in Note 13, the Company has a loan and security agreement with Silicon Valley Bank. The carrying amount of the Company's borrowings approximates fair value at December 31, 2012. The Company's secured debt is classified as Level 2 and the fair value is estimated using quoted prices for similar liabilities in active markets, as well as inputs that are observable for the liability (other than quoted prices), such as interest rates that are observable at commonly quoted intervals.

Warrants

The Company allocated $3.3 million of proceeds from its March 2010 registered direct offering to warrants issued in connection with the offering that was classified as a liability. The valuation of the warrants is determined using the Black-Scholes model. This model uses inputs such as the underlying price of the shares issued when the warrant is exercised, volatility, risk free interest rate and expected life of the instrument. The Company has determined that the warrant liability should be classified within Level 3 of the fair value hierarchy by evaluating each input for the Black-Scholes model against the fair value hierarchy criteria and using the lowest level of input as the basis for the fair value classification. There are six inputs: closing price of Amicus stock on the day of evaluation; the exercise price of the warrants; the remaining term of the warrants; the volatility of Amicus' stock over that term; annual rate of dividends; and the riskless rate of return. Of those inputs, the exercise price of the warrants and the remaining term are readily observable in the warrant agreements. The annual rate of dividends is based on the Company's historical practice of not granting dividends. The closing price of Amicus stock would fall under Level 1 of the fair value hierarchy as it is a quoted price in an active market. The riskless rate of return is a Level 2 input, while the historical volatility is a Level 3 input in accordance with the fair value accounting guidance. Since the lowest level input is a Level 3, the Company determined the warrant liability is most appropriately classified within Level 3 of the fair value hierarchy. This liability is subject to fair value mark-to-market adjustment each period. After the exercise of approximately 0.5 million warrants in 2012, the Company recognized the change in the fair value of the warrant liability as non-operating income of $0.7 million for the year ended December 31, 2012. The resulting fair value of the warrant liability at December 31, 2012 was $0.9 million. The weighted average assumptions used in the Black-Scholes valuation model for the warrants are as follows:

	December 31, 2011			December 31, 2012

Expected stock price volatility		67.3	%		93.2	%
Risk free interest rate		0.28	%		0.17	%
Expected life of warrants (years)		2.17			1.17
Expected annual dividend per share	$	0.00		$	0.00

A summary of the fair value of the Company's assets and liabilities aggregated by the level in the fair value hierarchy within which those measurements fall as of December 31, 2011 are identified in the following table (in thousands):

	Level 1		Level 2		Total

*Assets:*
Cash/Money market funds	$	25,668	$	—	$	25,668
U.S. government agency securities		—		2,000		2,000
Commercial paper		—		13,749		13,749
Corporate debt securities		—		13,935		13,935
Certificate of deposit		—		350		350

	$	25,668	$	30,034	$	55,702

	Level 1		Level 2		Level 3		Total

*Liabilities:*
Secured debt	$	—	$	1,044	$	—	$	1,044
Warrants liability		—		—		1,948		1,948

	$	—	$	1,044	$	1,948	$	2,992

A summary of the fair value of the Company's assets and liabilities aggregated by the level in the fair value hierarchy within which those measurements fall as of December 31, 2012 are identified in the following table (in thousands):

	Level 1		Level 2		Total

*Assets:*
Cash/Money market funds	$	33,971	$	—	$	33,971
Commercial paper		—		19,744		19,744
Corporate debt securities		—		42,497		42,497
Certificate of deposit		—		2,910		2,910

	$	33,971	$	65,151	$	99,122

	Level 1		Level 2		Level 3		Total

*Liabilities:*
Secured debt	$	—	$	697	$	—	$	697
Warrants liability		—		—		908		908

	$	—	$	697	$	908	$	1,605

The change in the fair value of the Level 3 liability was an increase of $1.4 million at December 31, 2010. The change in the fair value of the Level 3 liability was a decrease of $2.8 million at December 31, 2011. After settlement of $0.3 million upon the exercise of approximately 0.5 million warrants in 2012, the remaining change in the fair value of the Level 3 liability was a decrease of $0.7 million at December 31, 2012.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 107
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Reference 9: http://www.xbrl.org/2003/role/presentationRef
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Reference 11: http://www.xbrl.org/2003/role/presentationRef
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 157
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Reference 13: http://www.xbrl.org/2003/role/presentationRef
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+ Details

401(k) Plan	12 Months Ended
401(k) Plan	Dec. 31, 2012
401(k) Plan
401(k) Plan	8. 401(k) Plan The Company has a 401(k) plan (the Plan) covering all eligible employees. During 2007, the Board of Directors approved a company matching program that began on January 1, 2008. The matching program allows for a company match of up to 5% of salary and bonus paid during the year. The match vests in full one year following each participant's date of hire. The Company's total contribution to the Plan was $0.4 million, $0.6 million and $0.7 million for the years ended December 31, 2010, 2011 and 2012, respectively.

- Definition

The entire disclosure for pension and other postretirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-URI http://asc.fasb.org/topic&trid=2235017

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-Publisher FASB
-Name Implementation Guide (Q and A)
-Number FAS88
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
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Reference 9: http://www.xbrl.org/2003/role/presentationRef
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Reference 10: http://www.xbrl.org/2003/role/presentationRef
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
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Reference 13: http://www.xbrl.org/2003/role/presentationRef
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+ Details

Leases

12 Months Ended

Dec. 31, 2012

Leases

Leases

9. Leases

Operating Leases

In 2011, the Company entered into a lease agreement to lease approximately 73,646 square feet of laboratory and office space in Cranbury, New Jersey. The initial term of the lease, which commenced on March 1, 2012, is for seven years and may be extended by the Company for two additional five-year periods. In 2008, the Company entered into a lease agreement for its laboratory and office space in San Diego, CA, which will expire in September 2013 and may be extended by the Company for two additional five-year periods. Rent expenses for the Company's facilities are recognized over the term of the lease. The Company recognizes rent starting when possession of the facility is taken from the landlord. When a lease contains a predetermined fixed escalation of the minimum rent, the Company recognizes the related rent expense on a straight-line basis and records the difference between the recognized rental expense and the amounts payable under the lease as deferred rent liability. Tenant leasehold improvement allowances are reflected in accrued expenses on the consolidated balance sheets and are amortized as a reduction to rent expense in the statement of operations over the term of the lease.

At December 31, 2012, aggregate annual future minimum lease payments under these leases are as follows (in thousands):



Operating Leases
Years ending December 31:
2013	$	1,749
2014		1,540
2015		1,634
2016		1,735
2017 and beyond		3,844

	$	10,502

Rent expense for the years ended December 31, 2010, 2011 and 2012 were $2.3 million, $2.3 million and $2.6 million respectively.

- Definition

The entire disclosure for lessee entity's leasing arrangements including, but not limited to, all of the following: (a.) The basis on which contingent rental payments are determined, (b.) The existence and terms of renewal or purchase options and escalation clauses, (c.) Restrictions imposed by lease agreements, such as those concerning dividends, additional debt, and further leasing.

+ References + Details

Income Taxes

12 Months Ended

Dec. 31, 2012

Income Taxes

Income Taxes

10. Income Taxes

In June 2006, the FASB issued a single model to address accounting for uncertainty in tax positions. The model clarifies the accounting for income taxes, by prescribing a minimum recognition threshold a tax position is required to meet before being recognized in the financial statements. It also provides guidance on de-recognition, measurement, and classification of amounts relating to uncertain tax positions, accounting for and disclosure of interest and penalties, accounting in interim periods and disclosures required. The Company adopted the FASB requirements as of January 1, 2007 and determined that it did not have a material impact on the Company's financial position and results of operations. The Company did not recognize interest or penalties related to income tax during the period ended December 31, 2012 and did not accrue for interest or penalties as of December 31, 2012. The Company does not have an accrual for uncertain tax positions as of December 31, 2012. Tax returns for all years 2006 and thereafter are subject to future examination by tax authorities.

Deferred income taxes reflect the net effect of temporary difference between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. The significant components of the deferred tax assets and liabilities are as follows (in thousands):

	For Years Ended December 31,

	2011			2012
Current deferred tax asset
Non-cash stock issue	$	6,745		$	7,100
Others		662			1,257

		7,407			8,357
Non-current deferred tax assets
Amortization/depreciation		3,791			3,176
Research tax credit		4,325			9,072
Net operating loss carry forwards		48,930			62,060
Deferred revenue		10,985			12,149
Others		(236	)		520

Total deferred tax asset		75,202			95,334
Non-current deferred tax liability		—			—

Total net deferred tax asset		75,202			95,334
Less valuation allowance		(75,202	)		(95,334	)

Net deferred tax asset	$	—		$	—

The Company records a valuation allowance for temporary differences for which it is more likely than not that the Company will not receive future tax benefits. At December 31, 2011, and 2012, the Company recorded valuation allowances of $75.2 million and $95.3 million, respectively, representing an increase in the valuation allowance of $6.7 million in 2011 and an increase of $20.1 million in 2012, due to the uncertainty regarding the realization of such deferred tax assets, to offset the benefits of net operating losses generated during those years.

As of December 31, 2012, the Company had federal and state net operating loss carry forwards (NOLs) of approximately $154 million and $162 million, respectively. The federal carry forward will expire in 2028 through 2032. Most of the state carry forwards generated prior to 2009 began to expire in 2012 and will continue to expire through 2015. The remaining state carry forwards including those generated in 2009 through 2012 will expire in 2029 through 2032 due to a change in the New Jersey state law regarding the net operating loss carry forward period. Utilization of NOLs may be subject to a substantial annual limitation in the event of an ownership change that has occurred previously or could occur in the future pursuant to Section 382 of the Internal Revenue Code of 1986, as amended, as well as similar state provisions. An ownership change may limit the amount of NOLs that can be utilized annually to offset future taxable income and tax, and may, in turn, result in the expiration of a portion of those carry forwards before utilization. In general, an ownership change, as defined by Section 382, results from transactions that increase the ownership of certain shareholders or public groups in the stock of a corporation by more than 50 percentage points over a three year period. The Company completed a detailed study of its NOLs and determined that in 2012, there was no ownership change in excess of 50%; therefore there was no write-down to net realizable value of the federal NOLs and research and development credits subject to the 382 limitations. A tax benefit of $0.2 million associated with the exercise of stock options will be recorded in additional paid-in capital when the associated net operating loss is recognized.

A reconciliation of the statutory tax rates and the effective tax rates for the years ended December 31, 2010, 2011 and 2012 are as follows:

	Years Ended December 31,

	2010			2011			2012
Statutory rate		(34	)%		(34	)%		(34	)%
State taxes, net of federal benefit		(8	)		(13	)		(3	)
Permanent adjustments		51			3			—
R&D credit		(4	)		—			(8	)
Other		—			2			1
Valuation allowance		(7	)		34			38

Net		(2	)%		(8	)%		(6	)%

The Company recognized a tax benefit of $1.1 million, $3.6 million and $3.2 million in connection with the sale of net operating losses and research and development credits in the New Jersey Transfer Program for the years ended December 31, 2010, 2011 and 2012, respectively.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

+ Details

Licenses	12 Months Ended
Licenses	Dec. 31, 2012
Licenses
Licenses	11. Licenses The Company acquired rights to develop and commercialize its product candidates through licenses granted by various parties. The following summarizes the Company's material rights and obligations under those licenses: Mt. Sinai School of Medicine of New York University (MSSM) — The Company acquired exclusive worldwide patent rights to develop and commercialize migalastat HCl, afegostat tartrate and AT2220 and other pharmacological chaperones for the prevention or treatment of human diseases or clinical conditions by increasing the activity of wild-type and mutant enzymes pursuant to a license agreement with MSSM. In connection with this agreement, the Company issued 232,266 shares of common stock to MSSM in April 2002. In 2006, the Company amended its license agreement with MSSM to expand its exclusive worldwide patent rights to develop and commercialize pharmacological chaperones. In connection with the amendment, the Company paid $1.0 million and issued 133,333 shares of its common stock with an estimated fair value of $1.2 million to MSSM. In total, the Company recorded $2.2 million of research and development expense in connection with the amendment in 2006. This agreement expires upon expiration of the last of the licensed patent rights, which will be in 2019, subject to any patent term extension that may be granted, or 2024 if the Company develops a product for combination therapy (pharmacological chaperone plus ERT) and a patent issues from the pending application covering combination therapy, subject to any patent term extension that may be granted. Under this agreement, to date the Company has paid no upfront or annual license fees and has no milestone or future payments other than royalties on net sales. In 2008, the Company amended and restated its license agreement with MSSM which consolidated previous amendments into a single agreement, clarified the portion of royalties and milestone payments the Company received from collaboration agreements that were payable to MSSM, and provided the Company with the sole right to control the prosecution of patent rights described in the amended and restated license agreement. For further information see "— Note 12. Collaboration Agreements." Under the terms of the amended and restated license agreement, the Company agreed to pay $2.6 million to MSSM in connection with the $50 million upfront payment that the Company received from a collaboration agreement in November 2007 and an additional $2.6 million for the sole right to and control over the prosecution of patent rights. In accordance with the Company's license agreement with MSSM, the Company paid $3 million of the $30 million upfront payment received from GSK to MSSM in December 2010 and $0.35 million of the $3.5 million milestone payment received from GSK in August 2012, pursuant to the Original Collaboration Agreement. These payments to MSSM are classified as research and development expenses in the Company's financial statements. University of Maryland, Baltimore County — The Company acquired exclusive U.S. patent rights to develop and commercialize afegostat tartrate for the treatment of Gaucher disease from the University of Maryland, Baltimore County. Under this agreement, the Company paid upfront and annual license fees of $45 thousand, which were expensed as research and development expense. The Company is required to make a milestone payment upon the demonstration of safety and efficacy of afegostat tartrate for the treatment of Gaucher disease in a Phase 2 study, and another payment upon receiving FDA approval for afegostat tartrate for the treatment of Gaucher disease. Upon satisfaction of both milestones, the Company could be required to make up to $0.2 million in aggregate payments. The Company is also required to pay royalties on net sales. This agreement expires upon expiration of the last of the licensed patent rights in 2015. Novo Nordisk A/S — The Company acquired exclusive patent rights to develop and commercialize afegostat tartrate for all human indications. Under this agreement, to date the Company paid $0.4 million in license fees which were expensed as research and development expense. The Company is also required to make milestone payments based on clinical progress of afegostat tartrate, with a payment due after initiation of a Phase 3 clinical trial for afegostat tartrate for the treatment of Gaucher disease, and a payment due upon each filing for regulatory approval of afegostat tartrate for the treatment of Gaucher disease in any of the US, Europe or Japan. An additional payment is due upon approval of afegostat tartrate for the treatment of Gaucher disease in the U.S. and a payment is also due upon each approval of afegostat tartrate for the treatment of Gaucher disease in either Europe or Japan. Assuming successful development of afegostat tartrate for the treatment of Gaucher disease in the U.S., Europe and Japan, total milestone payments would be $7.8 million. The Company is also required to pay royalties on net sales. This license will terminate in 2016. Under its license agreements, if the Company owes royalties on net sales for one of its products to more than one of the above licensors, then it has the right to reduce the royalties owed to one licensor for royalties paid to another. The amount of royalties to be offset is generally limited in each license and can vary under each agreement. For migalastat HCl and AT2220, the Company will owe royalties only to MSSM and will owe no milestone payments. The Company would expect to pay royalties to all three licensors with respect to afegostat tartrate should the Company advance it to commercialization. The Company's rights with respect to these agreements to develop and commercialize migalastat HCl, afegostat tartrate and AT2220 may terminate, in whole or in part, if the Company fails to meet certain development or commercialization requirements or if the Company does not meet its obligations to make royalty payments.

Collaborative Agreements	12 Months Ended
Collaborative Agreements	Dec. 31, 2012
Collaborative Agreements
Collaborative Agreements	12. Collaborative Agreements GSK On October 28, 2010, the Company entered into the Original Collaboration Agreement with Glaxo Group Limited, an affiliate of GSK, to develop and commercialize migalastat HCl. Under the terms of the Original Collaboration Agreement, GSK received an exclusive worldwide license to develop, manufacture and commercialize migalastat HCl. In consideration of the license grant, the Company received an upfront, license payment of $30 million from GSK and was eligible to receive further payments of approximately $173.5 million upon the successful achievement of development, regulatory and commercialization milestones, as well as tiered double-digit royalties on global sales of migalastat HCl. Potential payments included up to (i) $13.5 million related to the attainment of certain clinical development objectives and the acceptance of regulatory filings in select worldwide markets, (ii) $80 million related to market approvals for migalastat HCl in selected territories throughout the world, and (iii) $80 million associated with the achievement of certain sales thresholds. GSK and the Company were jointly funding development costs in accordance with an agreed upon development plan. Additionally, GSK purchased approximately 6.9 million shares of the Company's common stock at $4.56 per share, a 30% premium on the average price per share of the Company's stock over a 60 day period preceding the closing date of the transaction. The total value of this equity investment to the Company was approximately $31 million. On July 17, 2012, the Company entered into the Expanded Collaboration Agreement with GSK pursuant to which the Company and GSK continue to develop and commercialize migalastat HCl, currently in Phase 3 development for the treatment of Fabry disease. The Expanded Collaboration Agreement amends and replaces in its entirety the Original Collaboration Agreement. Under the terms of the Expanded Collaboration Agreement, the Company and GSK will co-develop all formulations of migalastat HCl for Fabry disease, including the development of migalastat HCl co-formulated with an investigational enzyme replacement therapy (ERT) for Fabry disease (the "Co-formulated Product") in collaboration with another GSK collaborator JCR Pharmaceutical Co., Ltd. The Company will commercialize all migalastat HCl products for Fabry disease in the United States while GSK will commercialize all such products in the rest of the world. The exclusive license granted to GSK under the Original Collaboration Agreement to commercialize migalastat HCl worldwide was replaced under the Expanded Collaboration Agreement, which grants two exclusive licenses: (i) an exclusive license from GSK to the Company to commercialize migalastat HCl in the United States, and (ii) an exclusive license from the Company to GSK to commercialize migalastat HCl in the rest of world. Amicus and GSK each have a license to manufacture migalastat HCl for commercialization of monotherapy and chaperone-ERT co-administration migalastat HCl products while GSK maintains an exclusive license to manufacture such products for development purposes (subject to limited exceptions) and to manufacture the Co-formulated Product. In the event of a change of control in the Company during the term of the Expanded Collaboration Agreement, GSK has the option to purchase an exclusive license to develop, manufacture and commercialize migalastat HCl in the United States. GSK is eligible to receive U.S. regulatory approval milestones totaling $20 million for migalastat HCl monotherapy and migalastat HCl-ERT co-administration, and additional regulatory approval and product launch milestone payments totaling up to $35 million within seven years following the launch of the Co-formulated Product. The Company will also be responsible for certain pass-through milestone payments and single-digit royalties on the net U.S. sales of the Co-formulated Product that GSK must pay to a third party. In addition, the Company is no longer eligible to receive any milestones or royalties it would have been eligible to receive under the Original Collaboration Agreement other than a $3.5 million clinical development milestone achieved in the second quarter of 2012 and paid by GSK to Amicus in the third quarter of 2012. The Company and GSK will continue to jointly fund development costs for all formulations of migalastat HCl in accordance with agreed upon development plans pursuant to which the Company and GSK funded 25% and 75% of such costs, respectively, for the monotherapy and co-administration programs during 2012 and 40% and 60%, respectively, in 2013 and beyond. Effective upon entry into the Expanded Collaboration Agreement, costs for the development of the Co-formulated Product are also funded 40% and 60% between Amicus and GSK, respectively. Additionally, simultaneous with entry into the Expanded Collaboration Agreement, Amicus and GSK entered into an SPA pursuant to which GSK purchased approximately 2.9 million shares of Amicus common stock at a price of $6.30 per share. The SPA provides GSK with customary registration rights for the shares purchased and includes a six-month lock-up provision. The total purchase price was $18.6 million and the Company received all proceeds from the sale of such shares on July 26, 2012. As of December 31, 2012, GSK had a 19.8% ownership position in the Company as a result of the Original and Expanded Collaboration Agreements. Under the Original Collaboration Agreement, the upfront license fee, together with the premium received on the stock purchase, was being recognized as Collaboration Revenue over the original development period. In addition, the Company was receiving reimbursements of research expenditures under the cost sharing arrangement which was being accounted for as research revenue on the statement of operations. Under the Expanded Collaboration Agreement, the Company will continue to receive research expense reimbursements for the development of migalastat HCl but may be required to pay contingent milestones to GSK in the future related to the US commercial rights to migalastat HCl. In accordance with the revenue recognition guidance related to multiple-element arrangements, the Company identified all of the deliverables at the inception of the Expanded Collaboration Agreement. The significant deliverables were determined to be the rest of world licensing rights to migalastat HCl, the research services to continue and complete the development of migalastat HCl and the delivery of the Company's common stock. The Company determined that the rest of world licensing rights and the research services represent one unit of accounting as none of these deliverables on its own has standalone value separate from the other. The Company also determined that the delivery of the Company's common stock does have standalone value separate from the rest of world licensing rights and the research services. As a result, the Company's common stock was considered a separate unit of accounting and was accounted for as an issuance of common stock. However, as the Company's common stock was sold at a premium to the market closing price, the premium amount paid over the market closing price was determined to be additional consideration paid to the Company for the collaboration agreement and was included as consideration for the single unit of accounting (rest of world licensing rights and research services) identified above. In evaluating the impact of the Expanded Collaboration Agreement, the Company applied the accounting guidance regarding the impact of potential future payments it may make in its role as a vendor (Amicus) to its customer (GSK) and evaluated if these potential future payments could be a reduction of revenue from GSK. If the potential future payments to GSK are: • a payment for an identifiable benefit, and • the identifiable benefit is separable from the existing relationship between the Company and GSK, and • the identifiable benefit can be obtained from a party other than GSK, and • the Company can reasonably estimate the fair value of the identifiable benefit, then the potential future payments would be treated separately from the collaboration and research revenue. However, if all these criteria are not satisfied, then the potential future payments are treated as a reduction of revenue. Accordingly, the Company does not believe that, for accounting purposes, the new US licensing rights to migalastat HCl obtained from GSK represent a separate, identifiable benefit from the licenses in the Original Collaboration Agreement. The contingent amounts payable to GSK are not sufficiently separable from GSK's original license and the research and development reimbursements such that Amicus could not have entered into a similar exchange transaction with another party. Additionally, the Company cannot reasonably estimate the fair value of the US licensing rights to migalastat HCl. The Company determined that the potential future payments to GSK would be treated as a reduction of revenue and that the total amount of revenue to be received under the arrangement is no longer fixed or determinable as the contingent milestone payments are subject to significant uncertainty. As a result, the Company no longer recognizes any of the upfront license fee and premium on the equity purchase from GSK until such time as the arrangement consideration becomes fixed or determinable, because an indeterminable amount may ultimately be payable back to GSK. These amounts (the balance of the unrecognized upfront license fee and the premium on the equity purchases) are classified as deferred reimbursements on the balance sheet. The recognition of Research Revenue is also affected by the determination that the overall total arrangement consideration is no longer fixed and determinable, despite the fact that the research activities will continue and that the research expense reimbursements by GSK to Amicus will be received as the research activities related to the reimbursement would have already been completed. Therefore any research reimbursements from GSK are recorded as deferred reimbursements on the balance sheet and not recognized until the total arrangement consideration becomes fixed and determinable. As a result, all revenue recognition was suspended until the total arrangement consideration becomes fixed and determinable. In addition, future milestone payments made by the Company will be applied against the balance of this deferred reimbursements account. Revenue recognition for research expense reimbursements, the original upfront license fee, and the equity premiums will resume once the total arrangement consideration becomes fixed and determinable which will occur when the balance of the deferred reimbursements account is sufficient to cover all the remaining contingent milestone payments. Under the Original Collaboration Agreement, the Company evaluated the contingent milestones and determined that they were substantive milestones and would be recognized as revenue in the period that the milestone is achieved. The Company determined that the research based milestones were commensurate with the enhanced value of each delivered item as a result of the Company's specific performance to achieve the milestones. The research based milestones would have related to past performances when achieved and were reasonable relative to the other payment terms within the Original Collaboration Agreement. In June 2012, the Company achieved a clinical development milestone and recognized $3.5 million of milestone revenue. Under the terms of the Expanded Collaboration Agreement, the Company is no longer entitled to receive any milestone payments from GSK. Shire In November 2007, the Company entered into a collaboration agreement with Shire. Under the agreement, the Company and Shire were jointly developing the Company's three lead pharmacological chaperone compounds for lysosomal storage disorders: migalastat HCl, afegostat tartrate and AT2220. The Company granted Shire the rights to commercialize these products outside the U.S. and retained all rights to its other programs and to develop and commercialize migalastat HCl, afegostat tartrate and AT2220 in the U.S. The Company received an initial, non-refundable license fee payment of $50 million from Shire. Joint development costs toward global approval of the three compounds were being shared 50/50. In addition, the Company was eligible to receive milestone payments if certain clinical and regulatory and sales-based milestones were met. The Company was also eligible to receive tiered double-digit royalties on net sales of the products marketed outside of the U.S. In October 2009, the Company and Shire agreed to mutually terminate the collaboration agreement upon concluding that it was in their respective best interests to no longer collaborate on the development of the Company's three lead pharmacological chaperone compounds for the treatment of lysosomal storage disorders. As a result of this termination, Amicus reacquired all global development and commercialization rights from Shire for these lead programs. Shire paid the Company $5.2 million as full and final payment for amounts due to the Company under the collaboration agreement, and both parties were relieved of all other future obligations there under, financial or otherwise.

Short-Term Borrowings and Long-Term Debt

12 Months Ended

Dec. 31, 2012

Short-Term Borrowings and Long-Term Debt

Short-Term Borrowings and Long-Term Debt

13. Short-Term Borrowings and Long-Term Debt

In May 2009, the Company entered into a loan and security agreement with Silicon Valley Bank (SVB) that provided for up to $4 million of equipment financing. (the "2009 Loan Agreement"). Borrowings under the agreement were collateralized by equipment purchased with the proceeds of the loan and carried interest at a fixed rate of approximately 9%. The 2009 Loan Agreement contained customary terms and conditions, including a financial covenant whereby the Company maintained a minimum amount of liquidity measured at the end of each month where unrestricted cash, cash equivalents, and marketable securities, was greater than $20 million plus outstanding debt due to SVB. At December 31, 2012, there were no amounts outstanding from the 2009 Loan Agreement.

In addition, the Company committed to a second loan and security agreement with SVB in August 2011 (the "2011 Loan Agreement") in order to finance certain capital expenditures anticipated to be made by the Company in connection with its move in March 2012 to new office and laboratory space in Cranbury, New Jersey. The 2011 Loan Agreement provides for up to $3 million of equipment financing through January 2014. Borrowings under the 2011 Loan Agreement are collateralized by equipment purchased with the proceeds of the loan and bear interest at a variable rate of SVB prime + 2.5%. The current SVB prime rate is 4.0%. In February 2012, the Company borrowed approximately $1.0 million from the 2011 Loan Agreement which will be repaid over the following 2.5 years. The 2011 Loan Agreement contains the same financial covenant as the 2009 Loan Agreement. The Company has at all times been in compliance with these covenants during the term of both agreements.

At December 31, 2012, the total amount due under the 2011 Loan Agreement was $0.7 million. The carrying amount of the Company's borrowings approximates fair value at December 31, 2012.

The remaining future minimum payments due as of December 31, 2012 are as follows (in thousands):


Years ending December 31:
2013	$	398
2014		299
2015		—

Total principal obligation		697
Less short-term portion		(398	)

Long-term portion	$	299

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References + Details

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2012
Subsequent Events
Subsequent Events	14. Subsequent Events The Company evaluated events that occurred subsequent to December 31, 2012 and there were no material recognized or non-recognized subsequent events during this period.

Selected Quarterly Financial Data (Unaudited - in thousands except per share data)

12 Months Ended

Dec. 31, 2012

Selected Quarterly Financial Data (Unaudited - in thousands except per share data)

Selected Quarterly Financial Data (Unaudited - in thousands except per share data)

15. Selected Quarterly Financial Data (Unaudited — in thousands except per share data)

	Quarters Ended

	March 31			June 30			September 30			December 31
2011
Net loss		(13,350	)		(12,641	)		(9,759	)		(8,662	)
Basic and diluted net loss per common share ⁽¹⁾		(0.39	)		(0.37	)		(0.28	)		(0.25	)
2012
Net loss		(13,137	)		(9,343	)		(16,290	)		(10,015	)
Basic and diluted net loss per common share ⁽¹⁾		(0.35	)		(0.20	)		(0.34	)		(0.20	)

(1): Per common share amounts for the quarters and full years have been calculated separately. Accordingly, quarterly amounts do not add to the annual amounts because of differences on the weighted-average common shares outstanding during each period principally due to the effect of the Company issuing shares of its common stock during the year.

- Definition

The entire disclosure for the quarterly financial data in the annual financial statements. The disclosure may include a tabular presentation of financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income or loss before extraordinary items and earnings per share data. It also includes an indication if the information in the note is unaudited, comments on the aggregate effect of year-end adjustments, and an explanation of matters or transactions that affect comparability or are pertinent to an understanding of the information furnished.

+ References + Details

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2012

Summary of Significant Accounting Policies

Basis of Presentation

Basis of Presentation

Consolidation

Consolidation

Use of Estimates

Use of Estimates

Cash, Money Market Funds, and Marketable Securities

Cash, Money Market Funds, and Marketable Securities

The Company considers all highly liquid investments purchased with a maturity of three months or less at the date of acquisition, to be cash equivalents.

Concentration of Credit Risk

Concentration of Credit Risk

Property and Equipment

Property and Equipment

Impairment of Long-Lived Assets

Impairment of Long-Lived Assets

Revenue Recognition

Revenue Recognition

•

a payment for an identifiable benefit; and

•

the identifiable benefit is separable from the existing relationship between the Company and its customer; and

•

the identifiable benefit can be obtained from a party other than the customer; and

•

the Company can reasonably estimate the fair value of the identifiable benefit

Fair Value Measurements

Fair Value Measurements

Research and Development Costs

Research and Development Costs

Interest Income and Interest Expense

Interest Income and Interest Expense

Interest income consists of interest earned on the Company's cash and cash equivalents and marketable securities. Interest expense consists of interest incurred on capital leases and secured debt.

Other Income and Expenses

Other Income and Expenses

Income Taxes

Income Taxes

Other Comprehensive Income/ (Loss)

Other Comprehensive Income/ (Loss)

Components of other comprehensive income/ (loss) include unrealized gains and losses on available-for-sale securities and are included in the statements of comprehensive loss.

Leases

Leases

Stock-Based Compensation

Stock-Based Compensation

Basic and Diluted Net Loss Attributable to Common Stockholders per Common Share

Basic and Diluted Net Loss Attributable to Common Stockholders per Common Share

	Years Ended December 31,

	2010			2011			2012
Historical
Numerator:
Net loss attributable to common stockholders	$	(54,936	)	$	(44,412	)	$	(48,785	)

Denominator:
Weighted average common shares outstanding — basic and diluted		27,734,797			34,569,642			45,565,217

Dividends

Dividends

Recent Accounting Pronouncements

Recent Accounting Pronouncements

Segment Information

Segment Information

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2012

Summary of Significant Accounting Policies

Schedule of reconciliation of the numerator and denominator used in computing basic and diluted net loss attributable to common stockholders per common share

	Years Ended December 31,

	2010			2011			2012
Historical
Numerator:
Net loss attributable to common stockholders	$	(54,936	)	$	(44,412	)	$	(48,785	)

Denominator:
Weighted average common shares outstanding — basic and diluted		27,734,797			34,569,642			45,565,217

Cash, Money Market Funds and Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2012

Cash, Money Market Funds, and Marketable Securities

Schedule of cash, money market funds and marketable securities

Cash and available for sale securities consisted of the following as of December 31, 2011 and December 31, 2012 (in thousands):

	As of December 31, 2011

	Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash balances	$	25,668	$	—	$	—		$	25,668
U.S. government agency securities		2,000		—		—			2,000
Corporate debt securities		13,943		—		(8	)		13,935
Commercial paper		13,737		12		—			13,749
Certificate of deposit		350		—		—			350

	$	55,698	$	12	$	(8	)	$	55,702

Included in cash and cash equivalents	$	25,668	$	—	$	—		$	25,668
Included in marketable securities		30,030		12		(8	)		30,034

Total cash and marketable securities	$	55,698	$	12	$	(8	)	$	55,702

	As of December 31, 2012

	Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash balances	$	33,971	$	—	$	—		$	33,971
Corporate debt securities		42,503		5		(11	)		42,497
Commercial paper		19,725		19		—			19,744
Certificate of deposit		2,909		1		—			2,910

	$	99,108	$	25	$	(11	)	$	99,122

Included in cash and cash equivalents	$	33,971	$	—	$	—		$	33,971
Included in marketable securities		65,137		25		(11	)		65,151

Total cash and marketable securities	$	99,108	$	25	$	(11	)	$	99,122

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2012

Property and Equipment

Schedule of property and equipment

Property and equipment consist of the following (in thousands):

	December 31,

	2011			2012
Property and equipment consist of the following:
Computer equipment	$	2,556		$	3,399
Computer software		641			849
Research equipment		4,986			5,807
Furniture and fixtures		1,040			1,544
Leasehold improvements		2,722			1,931

		11,945			13,530
Less accumulated depreciation and amortization		(9,507	)		(8,501	)

	$	2,438		$	5,029

Accounts Payable and Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2012

Accounts Payable and Accrued Expenses

Schedule of accounts payable and accrued expenses

Accrued expenses consist of the following (in thousands):

	December 31,

	2011		2012
Accounts payable	$	2,576	$	2,115
Accrued professional fees		215		409
Accrued contract manufacturing & contract research costs		3,489		1,743
Accrued compensation and benefits		3,162		4,229
Accrued facility costs		27		167
Accrued other		201		182
Accrued facilities consolidation		38		—

	$	9,708	$	8,845

Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2012

Stockholders' Equity

Summary of information related to stock compensation expense recognized in the income statement

The following table summarizes information related to stock compensation expense recognized in the statements of operations (in millions):

	Years Ended December 31,

	2010		2011		2012
Stock compensation expense recognized in:
Research and development expense	$	2.6	$	2.9	$	3.6
General and administrative expense		3.6		5.8		2.6

Total stock compensation expense	$	6.2	$	8.7	$	6.2

Schedule of fair value weighted-average assumptions

	Years Ended December 31,

	2010			2011			2012
Expected stock price volatility		80.5	%		78.8	%		77.2	%
Risk free interest rate		2.4	%		2.0	%		0.8	%
Expected life of options (years)		6.25			6.25			6.25
Expected annual dividend per share	$	0.00		$	0.00		$	0.00

Summary of option activities

	Number of Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value

	(in thousands)						(in thousands)
Options outstanding, December 31, 2009		4,818.9		$	8.01
Granted		788.7		$	2.96
Exercised		(25.9	)	$	0.64
Forfeited		(477.6	)	$	7.93

Options outstanding, December 31, 2010		5,104.1		$	7.27
Granted		2,217.0		$	5.92
Exercised		(108.5	)	$	3.88
Forfeited		(559.1	)	$	7.34

Options outstanding, December 31, 2011		6,653.5		$	6.87
Granted		2,846.6		$	5.34
Exercised		(437.0	)	$	3.73
Forfeited		(1,088.9	)	$	7.95

Options outstanding, December 31, 2012		7,974.2		$	6.35	7.4 years	$	46.0

Vested and unvested expected to vest, December 31, 2012		7,437.4		$	6.41	7.3 years	$	46.0
Exercisable at December 31, 2012		3,955.7		$	7.41	6.0 years	$	46.0

Summary of information on the Company's restricted stock

	Restricted Stock

	Number of Shares			Weighted Average Grant Date Fair Value
	(in thousands)
Unvested at December 31, 2010		—		$	—
Granted		50.0		$	7.21
Vested		(50.0	)	$	7.21
Forfeited		—		$	—

Unvested at December 31, 2011		—		$	—
Granted		—		$	—
Vested		—		$	—
Forfeited		—		$	—

Unvested at December 31, 2012		—		$	—

- Definition

Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the balance sheet and income statement for the period. This may include the reporting line for the costs and the amount capitalized and expensed.

+ References + Details

Assets and Liabilities Measured at Fair Value (Tables)

12 Months Ended

Dec. 31, 2012

Assets and Liabilities Measured at Fair Value

Schedule of weighted average assumptions used in the Black-Scholes valuation model for the warrants

	December 31, 2011			December 31, 2012

Expected stock price volatility		67.3	%		93.2	%
Risk free interest rate		0.28	%		0.17	%
Expected life of warrants (years)		2.17			1.17
Expected annual dividend per share	$	0.00		$	0.00

Schedule of financial assets and liabilities subject to fair value measurements

	Level 1		Level 2		Total

*Assets:*
Cash/Money market funds	$	25,668	$	—	$	25,668
U.S. government agency securities		—		2,000		2,000
Commercial paper		—		13,749		13,749
Corporate debt securities		—		13,935		13,935
Certificate of deposit		—		350		350

	$	25,668	$	30,034	$	55,702

	Level 1		Level 2		Level 3		Total

*Liabilities:*
Secured debt	$	—	$	1,044	$	—	$	1,044
Warrants liability		—		—		1,948		1,948

	$	—	$	1,044	$	1,948	$	2,992

	Level 1		Level 2		Total

*Assets:*
Cash/Money market funds	$	33,971	$	—	$	33,971
Commercial paper		—		19,744		19,744
Corporate debt securities		—		42,497		42,497
Certificate of deposit		—		2,910		2,910

	$	33,971	$	65,151	$	99,122

	Level 1		Level 2		Level 3		Total

*Liabilities:*
Secured debt	$	—	$	697	$	—	$	697
Warrants liability		—		—		908		908

	$	—	$	697	$	908	$	1,605

- Definition

Tabular disclosure related to assets and liabilities by class, including financial instruments measured at fair value that are classified in shareholders' equity, if any, that are measured at fair value on a recurring and/or nonrecurring basis in periods after initial recognition. Disclosures include, but are not limited to: (a) the fair value measurements recorded and the reasons for the measurements and (b) the level within the fair value hierarchy in which the fair value measurements are categorized in their entirety (levels 1, 2, 3) as well as transfers between levels 1 and 2.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19279-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a,b,bb)
-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2C
-URI http://asc.fasb.org/extlink&oid=7578670&loc=SL7498348-110258

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19190-110258

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 33
-Subparagraph a, b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 6
-Footnote 4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

- Definition

Tabular disclosure of the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such certain disclosures about the financial instruments, assets, and liabilities include: (1) the fair value of the required items together with their carrying amounts (as appropriate) and (2) the methodology and assumptions used in developing such estimates of fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13476-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13467-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6447952&loc=d3e13220-108610

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=7491637&loc=d3e13433-108611

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 14
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15
-Subparagraph b-d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 18
-Subparagraph c(2), d, e, f
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph a, c(1), c(2), c(3), d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 10
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Leases (Tables)

12 Months Ended

Dec. 31, 2012

Leases

Schedule of aggregate annual future minimum lease payments under the leases

At December 31, 2012, aggregate annual future minimum lease payments under these leases are as follows (in thousands):



Operating Leases
Years ending December 31:
2013	$	1,749
2014		1,540
2015		1,634
2016		1,735
2017 and beyond		3,844

	$	10,502

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2012

Income Taxes

Schedule of significant components of the deferred tax assets and liabilities

The significant components of the deferred tax assets and liabilities are as follows (in thousands):

	For Years Ended December 31,

	2011			2012
Current deferred tax asset
Non-cash stock issue	$	6,745		$	7,100
Others		662			1,257

		7,407			8,357
Non-current deferred tax assets
Amortization/depreciation		3,791			3,176
Research tax credit		4,325			9,072
Net operating loss carry forwards		48,930			62,060
Deferred revenue		10,985			12,149
Others		(236	)		520

Total deferred tax asset		75,202			95,334
Non-current deferred tax liability		—			—

Total net deferred tax asset		75,202			95,334
Less valuation allowance		(75,202	)		(95,334	)

Net deferred tax asset	$	—		$	—

Schedule of reconciliation of the statutory tax rates and the effective tax rates

	Years Ended December 31,

	2010			2011			2012
Statutory rate		(34	)%		(34	)%		(34	)%
State taxes, net of federal benefit		(8	)		(13	)		(3	)
Permanent adjustments		51			3			—
R&D credit		(4	)		—			(8	)
Other		—			2			1
Valuation allowance		(7	)		34			38

Net		(2	)%		(8	)%		(6	)%

Short-Term Borrowings and Long-Term Debt (Tables)

12 Months Ended

Dec. 31, 2012

Short-Term Borrowings and Long-Term Debt

Schedule of remaining future minimum payments due

The remaining future minimum payments due as of December 31, 2012 are as follows (in thousands):


Years ending December 31:
2013	$	398
2014		299
2015		—

Total principal obligation		697
Less short-term portion		(398	)

Long-term portion	$	299

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e),(f))
-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6584090&loc=d3e28878-108400

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21538-112644

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21521-112644

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

+ Details

Selected Quarterly Financial Data (Unaudited - in thousands except per share data) (Tables)

12 Months Ended

Dec. 31, 2012

Selected Quarterly Financial Data (Unaudited - in thousands except per share data)

Schedule of selected quarterly financial data

Selected Quarterly Financial Data (Unaudited — in thousands except per share data)

	Quarters Ended

	March 31			June 30			September 30			December 31
2011
Net loss		(13,350	)		(12,641	)		(9,759	)		(8,662	)
Basic and diluted net loss per common share ⁽¹⁾		(0.39	)		(0.37	)		(0.28	)		(0.25	)
2012
Net loss		(13,137	)		(9,343	)		(16,290	)		(10,015	)
Basic and diluted net loss per common share ⁽¹⁾		(0.35	)		(0.20	)		(0.34	)		(0.20	)

(1): Per common share amounts for the quarters and full years have been calculated separately. Accordingly, quarterly amounts do not add to the annual amounts because of differences on the weighted-average common shares outstanding during each period principally due to the effect of the Company issuing shares of its common stock during the year.

Description of Business (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands				1 Months Ended				12 Months Ended		131 Months Ended
	Jul. 26, 2012	Jul. 17, 2012	Oct. 28, 2010	Jul. 31, 2012	Mar. 31, 2012	Oct. 31, 2010	Mar. 31, 2010	Dec. 31, 2012	Dec. 31, 2010	Dec. 31, 2012	Oct. 26, 2012	Jun. 30, 2012	Dec. 31, 2011
Corporate Information, Status of Operations and Management Plans
Price per share of common stock issued as part of the license and collaboration agreement (in dollars per share)					$ 5.70		$ 3.74
Total purchase price (in dollars)								$ 18,140	$ 28,083
Accumulated deficit								(318,889)		$ (318,889)			$ (270,104)
Common stock issued (in shares)					11,500		4,950
Warrants issued (in shares)							1,900
Proceeds from the issuance of common stock and warrants (in dollars)					$ 62,000		$ 17,100	$ 80,195	$ 45,214	$ 193,441
Stock issued from collaboration agreement (in shares)							4,900
GSK \| Original Collaboration Agreement
Corporate Information, Status of Operations and Management Plans
Potential milestone payments receivable			$ 173,500
Price per share of common stock issued as part of the license and collaboration agreement (in dollars per share)			$ 4.56			$ 4.56
Proceeds from the issuance of common stock and warrants (in dollars)			$ 31,000			$ 31,000
Stock issued from collaboration agreement (in shares)			6,900			6,900
GSK \| Expanded Collaboration Agreement
Corporate Information, Status of Operations and Management Plans
Percentage of development costs funded by the entity in 2012				40.00%
Percentage of development costs funded by the counterparty in 2012				60.00%
Percentage of development costs funded by the entity		40.00%
Percentage of development costs funded by the counterparty		60.00%
Common stock issued (in shares)								2,900
Proceeds from the issuance of common stock and warrants (in dollars)								$ 18,600
GSK \| SPA
Corporate Information, Status of Operations and Management Plans
Price per share of common stock issued as part of the license and collaboration agreement (in dollars per share)				$ 6.30							$ 6.30
Total purchase price (in dollars)	$ 18,600							$ 18,600
Ownership position in the company (as a percent)				19.80%
Stock issued from collaboration agreement (in shares)	2,900			2,900
GSK \| U.S. regulatory approval milestones for migalastat HCl monotherapy and migalastat HCl-ERT co-administration
Corporate Information, Status of Operations and Management Plans
Potential milestone payments receivable		$ 20,000
Percentage of development costs funded by the entity in 2012		25.00%
Percentage of development costs funded by the counterparty in 2012		75.00%
Percentage of development costs funded by the entity, thereafter		40.00%
Percentage of development costs funded by the counterparty, thereafter		60.00%
GSK \| U.S. regulatory approval milestones for migalastat HCl monotherapy and migalastat HCl-ERT co-administration \| Expanded Collaboration Agreement
Corporate Information, Status of Operations and Management Plans
Potential milestone payments receivable		$ 20,000
Additional potential milestone payments receivable		$ 35,000
Period of additional potential milestone payments receivable		7 years
GSK \| U.S. regulatory approval milestones for migalastat HCl monotherapy and migalastat HCl-ERT co-administration \| Expanded Collaboration Agreement \| Maximum
Corporate Information, Status of Operations and Management Plans
Additional potential milestone payments receivable				$ 35,000
Period of additional potential milestone payments receivable				7 years
GSK \| Clinical development objectives and the acceptance of regulatory filings milestone \| Original Collaboration Agreement
Corporate Information, Status of Operations and Management Plans
Potential milestone payments receivable			$ 13,500									$ 3,500
GSK \| Market approvals for migalastat HCl milestone \| Original Collaboration Agreement
Corporate Information, Status of Operations and Management Plans
Potential milestone payments receivable			80,000
GSK \| Achievement of certain sales thresholds milestone \| Original Collaboration Agreement
Corporate Information, Status of Operations and Management Plans
Potential milestone payments receivable			$ 80,000

Summary of Significant Accounting Policies (Details)	12 Months Ended
Summary of Significant Accounting Policies (Details)	Dec. 31, 2012
Minimum
Property and Equipment
Estimated useful lives	3 years
Maximum
Property and Equipment
Estimated useful lives	5 years

Summary of Significant Accounting Policies (Details 2)	Dec. 31, 2012 item
Stock-Based Compensation
Number of stock-based employee compensation plans	3

Summary of Significant Accounting Policies (Details 3) $ in Thousands	12 Months Ended			131 Months Ended
	Dec. 31, 2012 USD ($) item shares	Dec. 31, 2011 USD ($) shares	Dec. 31, 2010 USD ($) shares	Dec. 31, 2012 USD ($)
Numerator:
Net loss attributable to common stockholders \| $	$ (48,785)	$ (44,412)	$ (54,936)	$ (339,115)
Denominator:
Weighted average common shares outstanding - basic and diluted	45,565,217	34,569,642	27,734,797
Segment Information
Number of business segments \| item	1
Common stock options
Antidilutive securities
Antidilutive securities excluded from computation of diluted earnings per share (in shares)	9,400,000	8,500,000	7,000,000

- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Diluted Earnings Per Share
-URI http://asc.fasb.org/extlink&oid=6510752

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
-URI http://asc.fasb.org/extlink&oid=6508534

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 40
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 13, 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 07-4
-Paragraph 4
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 171
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Cash, Money Market Funds and Marketable Securities (Details) - USD ($) $ in Thousands	12 Months Ended									131 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008	Dec. 31, 2007	Dec. 31, 2006	Dec. 31, 2005	Dec. 31, 2004	Dec. 31, 2012	Feb. 03, 2002
Cash, Money Market Funds, and Marketable Securities
Cash and cash equivalents, Amortized Cost	$ 33,971	$ 25,668	$ 29,572	$ 19,339						$ 33,971	$ 0
Cash and cash equivalents, Fair Value	33,971	25,668								33,971
Marketable securities, Amortized Cost	65,137	30,030								65,137
Unrealized Gain	25	12								25
Unrealized Loss	(11)	(8)								(11)
Marketable securities, Fair Value	65,151	30,034								65,151
Cash and marketable securities, Amortized Cost	99,108	55,698								99,108
Cash and marketable securities, Fair Value	99,122	55,702								99,122
Unrealized holding gains included in the statements of comprehensive loss	10	32	$ (71)	$ (490)	$ 125	$ 393	$ 31	$ (7)	$ (9)	14
Available-for-sale investments
Unrealized holding gains included in other comprehensive income	10	32								10
Fair value of available for sale securities in unrealized loss positions	33,100	13,200								33,100
U.S. government agency securities
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost		2,000
Marketable securities, Fair Value		2,000
Corporate debt securities
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	42,503	13,943								42,503
Unrealized Gain	5									5
Unrealized Loss	(11)	(8)								(11)
Marketable securities, Fair Value	42,497	13,935								42,497
Commercial paper
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	19,725	13,737								19,725
Unrealized Gain	19	12								19
Marketable securities, Fair Value	19,744	13,749								19,744
Certificate of deposit
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	2,909	350								2,909
Unrealized Gain	1									1
Marketable securities, Fair Value	$ 2,910	$ 350								$ 2,910

Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended			131 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012
Property and Equipment
Property and equipment, gross	$ 13,530	$ 11,945		$ 13,530
Less accumulated depreciation and amortization	(8,501)	(9,507)		(8,501)
Property and equipment, net	5,029	2,438		5,029
Depreciation and amortization expense relating to the capital lease obligations	1,705	1,585	$ 2,058	11,768
Computer equipment
Property and Equipment
Property and equipment, gross	3,399	2,556		3,399
Computer software
Property and Equipment
Property and equipment, gross	849	641		849
Research equipment
Property and Equipment
Property and equipment, gross	5,807	4,986		5,807
Furniture and fixtures
Property and Equipment
Property and equipment, gross	1,544	1,040		1,544
Leasehold improvements
Property and Equipment
Property and equipment, gross	$ 1,931	$ 2,722		1,931
Property and equipment that are under capital lease obligation
Property and Equipment
Depreciation and amortization expense relating to the capital lease obligations			$ 1,700	$ 6,900

Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2012	Dec. 31, 2011
Accrued expenses
Accounts payable	$ 2,115	$ 2,576
Accrued professional fees	409	215
Accrued contract manufacturing & contract research costs	1,743	3,489
Accrued compensation and benefits	4,229	3,162
Accrued facility costs	167	27
Accrued other	182	201
Accrued facilities consolidation		38
Accounts payable and accrued expenses	$ 8,845	$ 9,708

- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References + Details

- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References + Details

Stockholders' Equity (Details) $ / shares in Units, $ in Thousands			1 Months Ended				3 Months Ended	12 Months Ended		131 Months Ended
	Jul. 26, 2012 USD ($) shares	Oct. 28, 2010 USD ($) $ / shares shares	Jul. 31, 2012 $ / shares shares	Mar. 31, 2012 USD ($) $ / shares shares	Oct. 31, 2010 USD ($) $ / shares shares	Mar. 31, 2010 USD ($) $ / shares shares	Mar. 31, 2012 USD ($) $ / shares	Dec. 31, 2012 USD ($) item shares	Dec. 31, 2010 USD ($)	Dec. 31, 2012 USD ($) item shares	Oct. 26, 2012 $ / shares	Dec. 31, 2011 shares
Stockholders' Equity
Authorized number of shares of common stock								125,000,000		125,000,000		125,000,000
Voting right for each share held, number \| item								1		1
Warrants exercised (in shares)								500,000
Fair value of the warrant liability \| $								$ 900		$ 900
Collaborative Agreements
Stock issued from collaboration agreement (in shares)						4,900,000
Common stock issued (in shares)				11,500,000		4,950,000
Offering price (in dollars per share) \| $ / shares				$ 5.70		$ 3.74	$ 5.70
Total purchase price (in dollars) \| $								18,140	$ 28,083
Aggregate offering proceeds from issuance of common stock (in dollars) \| $						$ 18,500	$ 65,600
Warrants issued (in shares)						1,900,000
Number of common stock sold in a unit (in shares)						1
Number of warrants sold in a unit (in shares)						1
Portion of share purchased against a unit						0.375
Warrant term						4 years
Exercise period of warrants on or after date of issue						6 months
Exercise price of warrants (in dollars per share) \| $ / shares						4.43
Proceeds from the issuance of common stock and warrants (in dollars) \| $				$ 62,000		$ 17,100		$ 80,195	$ 45,214	$ 193,441
Warrants outstanding								1,400,000		1,400,000
GSK \| SPA
Collaborative Agreements
Stock issued from collaboration agreement (in shares)	2,900,000		2,900,000
Offering price (in dollars per share) \| $ / shares			$ 6.30								$ 6.30
Total purchase price (in dollars) \| $	$ 18,600							$ 18,600
Ownership position in the company (as a percent)			19.80%
GSK \| Original Collaboration Agreement
Collaborative Agreements
Stock issued from collaboration agreement (in shares)		6,900,000			6,900,000
Offering price (in dollars per share) \| $ / shares		$ 4.56			$ 4.56
Proceeds from the issuance of common stock and warrants (in dollars) \| $		$ 31,000			$ 31,000

Stockholders' Equity (Details 2) - Stock options	12 Months Ended
Stockholders' Equity (Details 2) - Stock options	Dec. 31, 2012 shares
Stockholders' Equity
Maximum term of option	10 years
2007 Director Plan
Stockholders' Equity
Maximum term of option	10 years
2002 Plan and 2007 Plan
Stockholders' Equity
Percentage of options vest on the first year anniversary	25.00%
Additional percentage of options that will vest each month after first anniversary	2.08%
Percentage of shares vested that may be exercised in whole or part	100.00%
2007 Plan and 2007 Director Plan \| Maximum
Stockholders' Equity
Number of shares reserved for issuance	3,277,079

Stockholder's Equity (Details 3) - USD ($) $ in Millions	12 Months Ended
Stockholder's Equity (Details 3) - USD ($) $ in Millions	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Stockholders' Equity
Additional stock option compensation expense		$ 2.7
Stock compensation expense
Total stock compensation expense	$ 6.2	8.7	$ 6.2
Research and development expense
Stock compensation expense
Total stock compensation expense	3.6	2.9	2.6
General and administrative expense
Stock compensation expense
Total stock compensation expense	$ 2.6	$ 5.8	$ 3.6

- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References + Details

Stockholder's Equity (Details 4) - USD ($)	12 Months Ended
Stockholder's Equity (Details 4) - USD ($)	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Stockholders' Equity
Minimum stock price volatility (as a percent)	75.00%
Stock-based compensation expenses	$ 6,200,000	$ 8,700,000	$ 6,200,000
Stock options plans
Fair value weighted-average assumptions:
Expected stock price volatility (as a percent)	77.20%	78.80%	80.50%
Risk free interest rate (as a percent)	0.80%	2.00%	2.40%
Expected life of options	6 years 3 months	6 years 3 months	6 years 3 months
Expected annual dividend per share (in dollars per share)	$ 0.00	$ 0.00	$ 0.00
Weighted-average grant-date fair value per share of options granted (in dollars per share)	$ 3.31	$ 4.11	$ 2.09
Number of Shares
Balance at the beginning of the period (in shares)	6,653,500	5,104,100	4,818,900
Options granted (in shares)	2,846,600	2,217,000	788,700
Stock issued from exercise of stock options, net (in shares)	(437,000)	(108,500)	(25,900)
Options forfeited (in shares)	(1,088,900)	(559,100)	(477,600)
Balance at the end of the period (in shares)	7,974,200	6,653,500	5,104,100
Vested and unvested expected to vest at the end of the period (in shares)	7,437,400
Exercisable at the end of the period (in shares)	3,955,700
Weighted Average Exercise Price
Balance at the beginning of the period (in dollars per share)	$ 6.87	$ 7.27	$ 8.01
Options granted (in dollars per share)	5.34	5.92	2.96
Options exercised (in dollars per share)	3.73	3.88	0.64
Options forfeited (in dollars per shares)	7.95	7.34	7.93
Balance at the end of the period (in dollars per share)	6.35	$ 6.87	$ 7.27
Vested and unvested expected to vest at the end of the period (in dollars per shares)	6.41
Exercisable at the end of the period (in dollars per share)	$ 7.41
Weighted Average Remaining Contractual Life
Balance at the end of the period	7 years 4 months 24 days
Vested and unvested expected to vest at the end of the period	7 years 3 months 18 days
Exercisable at the end of the period	6 years
Aggregate Intrinsic Value
Aggregate intrinsic value of options outstanding (in dollars)	$ 46,000
Aggregate intrinsic value of options vested and unvested expected to vest (in dollars)	46,000
Aggregate intrinsic value of options exercisable (in dollars)	46,000
Aggregate intrinsic value of options exercised (in dollars)	900,000	$ 300,000	$ 100,000
Total unrecognized compensation cost related to non-vested stock options granted (in dollars)	$ 10,400,000
Period of recognition compensation cost	2 years 7 months 6 days
Cash proceeds from stock options exercised (in dollars)	$ 1,600,000	$ 400,000	$ 20,000

Stockholder's Equity (Details 5) - Restricted stock $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2011 USD ($) $ / shares shares
Number of Shares
Granted (in shares)	50,000
Vested (in shares)	(50,000)
Weighted Average Grant Date Fair Value
Granted (in dollars per shares) \| $ / shares	$ 7.21
Vested (in dollars per shares) \| $ / shares	$ 7.21
Number of shares surrendered to fund minimum statutory tax withholding requirements	13,225
Total fair value of restricted stock awards vested during the period (in dollars) \| $	$ 0.4

Assets and Liabilities Measured at Fair Value (Details) $ in Thousands, shares in Millions	12 Months Ended			131 Months Ended
	Dec. 31, 2012 USD ($) item shares	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2009 USD ($)	Feb. 03, 2002 USD ($)
Assets and Liabilities Measured at Fair Value
Proceeds from issuance of warrants	$ 3,300
Number of inputs used in fair value classification \| item	6
Warrants exercised (in shares) \| shares	0.5
Change in fair value of warrant liability	$ (653)	$ (2,764)	$ 1,410	$ (1,553)
Weighted average assumptions used in the Black-Scholes valuation model for the warrants
Expected stock price volatility (as a percent)	93.20%	67.30%
Risk free interest rate (as a percent)	1.17%	0.28%
Expected life of warrants	1 year 2 months 1 day	2 years 2 months 1 day
Expected annual dividend per share (as a percent)	0.00%	0.00%
Assets:
Cash/Money market fund	$ 33,971	$ 25,668	29,572	33,971	$ 19,339	$ 0
Liabilities:
Warrant liability	908	1,948		908
Changes in Level 3 liability
(Decrease)/Increase in fair value	(700)	(2,800)	$ 1,400
Settlement amount received upon exercise of warrants	300
Level 1
Assets:
Cash/Money market fund	33,971	25,668		33,971
Fair value of assets	33,971	25,668		33,971
Level 2
Assets:
Fair value of assets	65,151	30,034		65,151
Liabilities:
Secured debt	697	1,044		697
Fair value of liabilities	697	1,044		697
Level 2 \| U.S. government agency securities
Assets:
Fair value of assets		2,000
Level 2 \| Corporate debt securities
Assets:
Fair value of assets	42,497	13,935		42,497
Level 2 \| Commercial paper
Assets:
Fair value of assets	19,744	13,749		19,744
Level 2 \| Certificate of deposit
Assets:
Fair value of assets	2,910	350		2,910
Level 3
Liabilities:
Warrant liability	908	1,948		908
Fair value of liabilities	908	1,948		908
Total
Assets:
Cash/Money market fund	33,971	25,668		33,971
Fair value of assets	99,122	55,702		99,122
Liabilities:
Secured debt	697	1,044		697
Warrant liability	908	1,948		908
Fair value of liabilities	1,605	2,992		1,605
Total \| U.S. government agency securities
Assets:
Fair value of assets		2,000
Total \| Corporate debt securities
Assets:
Fair value of assets	42,497	13,935		42,497
Total \| Commercial paper
Assets:
Fair value of assets	19,744	13,749		19,744
Total \| Certificate of deposit
Assets:
Fair value of assets	$ 2,910	$ 350		$ 2,910

401(k) Plan (Details) - USD ($) $ in Millions	12 Months Ended
401(k) Plan (Details) - USD ($) $ in Millions	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
401 (k) Plan
Maximum contribution by the company as a percentage of employee's salary and bonus paid during the year	5.00%
Period following each participant's date of hire over which matching contribution vests	1 year
Total contribution to the plan (in dollars)	$ 0.7	$ 0.6	$ 0.4

Leases (Details) $ in Thousands	12 Months Ended
Leases (Details) $ in Thousands	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($) ft² item	Dec. 31, 2010 USD ($)	Dec. 31, 2008 item
Operating Leases
Area of laboratory and office space leased (in square feet) \| ft²		73,646
Initial term of the lease agreement		7 years
Initial lease term \| item		2		2
Extended additional term of lease agreement		5 years		5 years
Annual future minimum lease payments
2013	$ 1,749
2014	1,540
2015	1,634
2016	1,735
2017 and beyond	3,844
Total	10,502
Rent expense	$ 2,600	$ 2,300	$ 2,300

Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2012	Dec. 31, 2011
Current deferred tax asset
Non-cash stock issue	$ 7,100	$ 6,745
Others	1,257	662
Total current deferred tax asset	8,357	7,407
Non-current deferred tax assets
Amortization/depreciation	3,176	3,791
Research tax credit	9,072	4,325
Net operating loss carry forwards	62,060	48,930
Deferred revenue	12,149	10,985
Others	520	(236)
Total deferred tax asset	95,334	75,202
Total net deferred tax asset	95,334	75,202
Less valuation allowance	(95,334)	(75,202)
Increase in the valuation allowance	$ 20,100	$ 6,700

Income Taxes (Details 2) $ in Millions	12 Months Ended
Income Taxes (Details 2) $ in Millions	Dec. 31, 2012 USD ($)
Net operating loss carry forwards
Maximum change in ownership percentage allowed before statutory limitations imposed on the availability of net operating losses (as a percent)	50.00%
Period for measuring the change in ownership	3 years
Tax benefit associated with exercise of stock options to be recorded in additional paid-in capital on recognition of associated NOL	$ 0.2
Federal
Net operating loss carry forwards
Amount of net operating loss carry forwards	154.0
State
Net operating loss carry forwards
Amount of net operating loss carry forwards	$ 162.0

Income Taxes (Details 3) - USD ($) $ in Millions	12 Months Ended
Income Taxes (Details 3) - USD ($) $ in Millions	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Reconciliation of the statutory tax rates and the effective tax rates
Statutory rate (as a percent)	(34.00%)	(34.00%)	(34.00%)
State taxes, net of federal benefit (as a percent)	(3.00%)	(13.00%)	(8.00%)
Permanent adjustments (as a percent)		3.00%	51.00%
R&D credit (as a percent)	(8.00%)		(4.00%)
Other (as a percent)	1.00%	2.00%
Valuation allowance (as a percent)	38.00%	34.00%	(7.00%)
Net (as a percent)	(6.00%)	(8.00%)	(2.00%)
Income tax benefit from the sale of net operating losses and research and development credits	$ 3.2	$ 3.6	$ 1.1

Licenses (Details) $ in Thousands	1 Months Ended			12 Months Ended
Licenses (Details) $ in Thousands	Aug. 31, 2012 USD ($)	Nov. 30, 2007 USD ($)	Apr. 30, 2002 shares	Dec. 31, 2012 USD ($) item	Dec. 31, 2010 USD ($)	Dec. 31, 2008 USD ($)	Dec. 31, 2006 USD ($) shares
Licenses
Estimated fair value of stock issued in connection with the amendment to license agreement for license payment							$ 1,220
Shire
Licenses
Upfront payment received		$ 50,000
License agreement
Licenses
Number of licensors to whom the entity would expect to pay royalties \| item				3
License agreement \| MSSM
Licenses
Stock issued for in-process research and development (in shares) \| shares			232,266
Amount paid in connection with the amendment to license agreement for license payment							$ 1,000
Stock issued in connection with the amendment to license agreement for license payment (in shares) \| shares							133,333
Estimated fair value of stock issued in connection with the amendment to license agreement for license payment							$ 1,200
Total research and development expense in connection with the amendment							$ 2,200
Amount paid by the company in connection with the upfront payment received		$ 2,600			$ 3,000
Additional amount paid for the sole right to and control over the prosecution of patent rights						$ 2,600
Amount paid by the company in connection with the milestone payment received	$ 350
License agreement \| MSSM \| GSK
Licenses
Upfront payment received					$ 30,000
Milestone payment received	$ 3,500
License agreement \| MSSM \| Shire
Licenses
Upfront payment received						$ 50,000
License agreement \| University of Maryland, Baltimore County
Licenses
Upfront and annual license fees paid				$ 45
License agreement \| University of Maryland, Baltimore County \| Maximum
Licenses
Potential milestone payments				200
License agreement \| Novo Nordisk A/S
Licenses
Upfront and annual license fees paid				400
Potential milestone payments				$ 7,800

Collaborative Agreements (Details) $ / shares in Units, $ in Thousands, shares in Millions				1 Months Ended					3 Months Ended	12 Months Ended		131 Months Ended
	Jul. 26, 2012 USD ($) shares	Jul. 17, 2012 USD ($) item	Oct. 28, 2010 USD ($) $ / shares shares	Jul. 31, 2012 $ / shares shares	Mar. 31, 2012 USD ($) $ / shares	Oct. 31, 2010 USD ($) $ / shares shares	Mar. 31, 2010 USD ($) $ / shares shares	Nov. 30, 2007 USD ($) item	Jun. 30, 2012 USD ($)	Dec. 31, 2012 USD ($) item	Dec. 31, 2010 USD ($)	Dec. 31, 2012 USD ($)	Oct. 26, 2012 $ / shares	Oct. 31, 2009 USD ($)
Collaborative Agreements
Stock issued from collaboration agreement (in shares) \| shares							4.9
Price per share of common stock issued as part of the license and collaboration agreement (in dollars per share) \| $ / shares					$ 5.70		$ 3.74
Total value of the equity investment to the company					$ 62,000		$ 17,100			$ 80,195	$ 45,214	$ 193,441
Total purchase price (in dollars)										$ 18,140	$ 28,083
GSK
Collaborative Agreements
Number of accounting units \| item										1
Number of deliverables \| item										3
Premium over the closing market price of the common stock transaction										$ 3,200
Recognition period of arrangement consideration										5 years 2 months 12 days
Total arrangement consideration recognized as Collaboration Revenue										$ 6,600
GSK \| Original Collaboration Agreement
Collaborative Agreements
Upfront payment received			$ 30,000
Potential milestone payments receivable			$ 173,500
Stock issued from collaboration agreement (in shares) \| shares			6.9			6.9
Price per share of common stock issued as part of the license and collaboration agreement (in dollars per share) \| $ / shares			$ 4.56			$ 4.56
Percentage of premium on average price per share of common stock issued as part of the license and collaboration agreement			30.00%
Period preceding the closing date of the transaction over which average price per share of the company's stock is used			60 days
Total value of the equity investment to the company			$ 31,000			$ 31,000
GSK \| Expanded Collaboration Agreement
Collaborative Agreements
Percentage of development costs funded by the entity		40.00%
Total value of the equity investment to the company										18,600
Number of exclusive licenses \| item		2
Percentage of development costs funded by the entity in 2012				40.00%
Percentage of development costs funded by the counterparty in 2012				60.00%
Percentage of development costs funded by the counterparty		60.00%
GSK \| SPA
Collaborative Agreements
Stock issued from collaboration agreement (in shares) \| shares	2.9			2.9
Price per share of common stock issued as part of the license and collaboration agreement (in dollars per share) \| $ / shares				$ 6.30									$ 6.30
Ownership position in the company (as a percent)				19.80%
Total purchase price (in dollars)	$ 18,600									$ 18,600
Lock-up period for common stock issued as a part of SPA	6 months
GSK \| Clinical development objectives and the acceptance of regulatory filings milestone
Collaborative Agreements
Milestone revenue recognized									$ 3,500
GSK \| Clinical development objectives and the acceptance of regulatory filings milestone \| Original Collaboration Agreement
Collaborative Agreements
Potential milestone payments receivable			13,500						$ 3,500
GSK \| Market approvals for migalastat HCl milestone \| Original Collaboration Agreement
Collaborative Agreements
Potential milestone payments receivable			80,000
GSK \| Achievement of certain sales thresholds milestone \| Original Collaboration Agreement
Collaborative Agreements
Potential milestone payments receivable			$ 80,000
GSK \| U.S. regulatory approval milestones for migalastat HCl monotherapy and migalastat HCl-ERT co-administration
Collaborative Agreements
Potential milestone payments receivable		$ 20,000
Percentage of development costs funded by the entity in 2012		25.00%
Percentage of development costs funded by the counterparty in 2012		75.00%
Percentage of development costs funded by the entity, thereafter		40.00%
Percentage of development costs funded by the counterparty, thereafter		60.00%
GSK \| U.S. regulatory approval milestones for migalastat HCl monotherapy and migalastat HCl-ERT co-administration \| Expanded Collaboration Agreement
Collaborative Agreements
Potential milestone payments receivable		$ 20,000
Additional potential milestone payments receivable		$ 35,000
Period of additional potential milestone payments receivable		7 years
Shire
Collaborative Agreements
Upfront payment received								$ 50,000
Percentage of development costs funded by the entity								50.00%
Percentage of development costs funded by the counterparty								50.00%
Number of lead pharmacological chaperone compounds that the company and the counterparty were developing jointly \| item								3
Full and final payment received for the amounts due under the collaboration agreement														$ 5,200

Short-Term Borrowings and Long-Term Debt (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Feb. 29, 2012	Dec. 31, 2012	Dec. 31, 2011	May 31, 2009
Remaining future minimum payments due
2013		$ 398
2014		299
2015		0
Total principal obligation		697
Less short-term portion		(398)	$ (1,044)
Long-term portion		$ 299
2009 Loan Agreement
Short-Term Borrowings and Long-Term Debt
Maximum amount of loan				$ 4,000
Fixed interest rate (as a percent)		9.00%
Financial covenant, minimum amount of unrestricted cash, cash equivalents and marketable securities plus all outstanding borrowings		$ 20,000
2011 Loan Agreement
Short-Term Borrowings and Long-Term Debt
Maximum amount of loan		$ 3,000
Variable interest rate base, SVB prime rate		SVB prime
Percentage points added to the reference rate		2.50%
SVB prime rate (as a percent)		4.00%
Amount borrowed	$ 1,000	$ 700
Period for repayment of debt	2 years 6 months

Selected Quarterly Financial Data (Unaudited - in thousands except per share data) (Details) - USD ($)
$ / shares in Units, $ in Thousands

3 Months Ended

11 Months Ended

12 Months Ended

131 Months Ended

Dec. 31, 2012

Sep. 30, 2012

Jun. 30, 2012

Mar. 31, 2012

Dec. 31, 2011

Sep. 30, 2011

Jun. 30, 2011

Mar. 31, 2011

Dec. 31, 2002

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2010

Dec. 31, 2009

Dec. 31, 2008

Dec. 31, 2007

Dec. 31, 2006

Dec. 31, 2005

Dec. 31, 2004

Dec. 31, 2003

Dec. 31, 2012

Selected Quarterly Financial Data

Net loss (in dollars)

$ (10,015)

$ (16,290)

$ (9,343)

^[1]

$ (13,137)

$ (8,662)

$ (9,759)

$ (12,641)

$ (13,350)

$ (1,775)

$ (48,785)

$ (44,412)

$ (54,936)

$ (6,567)

$ (39,355)

$ (41,167)

$ (46,345)

$ (19,972)

$ (8,807)

$ (6,768)

$ (318,889)

Basic and diluted net loss per common share (in dollars per share)

$ (0.20)

$ (0.34)

$ (0.20)

$ (0.35)

$ (0.25)

$ (0.28)

$ (0.37)

$ (0.39)

$ (1.07)

$ (1.28)

$ (1.98)

[1]	(a) — Taxes have not been accrued on unrealized gain on securities as the Company is in a loss position for all periods presented.

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details