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Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2015	Apr. 24, 2015
Document and Entity Information
Entity Registrant Name	AMICUS THERAPEUTICS INC
Entity Central Index Key	0001178879
Document Type	10-Q
Document Period End Date	Mar. 31, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		96,421,182
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 28,827	$ 24,074
Investments in marketable securities	119,940	127,601
Prepaid expenses and other current assets	2,484	2,902
Total current assets	151,251	154,577
Available-for-sale Securities, Noncurrent	2,804	17,464
Property and equipment, less accumulated depreciation and amortization of $12,028 and $11,520 at March 31, 2015 and December 31, 2014 respectively	3,056	2,811
In-process research & development	23,000	23,000
Goodwill	11,613	11,613
Other non-current assets	892	502
Total Assets	192,616	209,967
Current liabilities:
Accounts payable and accrued expenses	15,833	16,345
Current portion of secured loan	5,189	3,840
Total current liabilities	21,022	20,185
Deferred reimbursements	36,620	36,620
Secured loan, less current portion	9,208	10,510
Contingent consideration payable	11,700	10,700
Deferred tax liability	9,186	9,186
Other non-current liability	870	588
Commitments and contingencies
Stockholders' equity:
Common stock, $.01 par value, 125,000,000 shares authorized, 96,375,015 shares issued and outstanding at March 31, 2015 95,556,277 shares issued and outstanding at December 31, 2014	1,024	1,015
Additional paid-in capital	574,757	568,743
Accumulated other comprehensive income	(35)	(132)
Accumulated Deficit	(471,736)	(447,448)
Total stockholders' equity	104,010	122,178
Total Liabilities and Stockholders' Equity	$ 192,616	$ 209,967

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2015	Dec. 31, 2014
Consolidated Balance Sheets
Accumulated depreciation of property and equipment (in dollars)	$ 12,028	$ 11,520
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	96,375,015	95,556,277
Common stock, shares outstanding	96,375,015	95,556,277

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Revenue:
Research revenue		$ 456
Total revenue		456
Operating Expenses:
Research and development	$ 16,113	9,992
General and administrative	6,427	5,176
Changes in fair value of contingent consideration payable	1,000	505
Restructuring charges	10	(8)
Depreciation	508	412
Total operating expenses	24,058	16,077
Loss from operations	(24,058)	(15,621)
Other income (expenses):
Interest income	171	42
Interest expense	(372)	(355)
Other expense	(29)	(9)
Net loss	$ (24,288)	$ (15,943)
Net loss attributable to common stockholders per common share - basic and diluted	$ (0.25)	$ (0.25)
Weighted-average common shares outstanding - basic and diluted	95,743,416	64,353,952

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Consolidated Statements of Comprehensive Loss
Net loss	$ (24,288)	$ (15,943)
Other comprehensive income/ (loss):
Unrealized gain on available-for-sale securities	97	1
Other comprehensive gain before income taxes	97	1
Other comprehensive income	97	1
Comprehensive loss	$ (24,191)	$ (15,942)

- Definition

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

+ References + Details

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Operating activities
Net loss	$ (24,288)	$ (15,943)
Adjustments to reconcile net loss to net cash used in operating activities:
Non-cash interest expense	83	59
Depreciation	508	412
Stock-based compensation	1,960	1,260
Restructuring charges	10	(8)
Non-cash changes in the fair value of contingent consideration payable	1,000	505
Changes in operating assets and liabilities:
Receivable due from collaboration agreements		589
Prepaid expenses and other current assets	418	3,893
Other non-current assets	(397)
Accounts payable and accrued expenses	(551)	(987)
Non-current liabilities	282
Net cash used in operating activities	(20,975)	(10,220)
Investing activities
Sale and redemption of marketable securities	40,739	11,465
Purchases of marketable securities	(18,321)	(17,227)
Purchases of property and equipment	(753)	(40)
Net cash provided by/ (used in) investing activities	21,665	(5,802)
Financing activities
Payments of secured loan agreement		(100)
Proceeds from exercise of stock options	4,063	15
Net cash provided by/(used in) financing activities	4,063	(85)
Net increase/(decrease) in cash and cash equivalents	4,753	(16,107)
Cash and cash equivalents at beginning of period	24,074	43,640
Cash and cash equivalents at end of period	28,827	27,533
Supplemental disclosures of cash flow information
Cash paid during the period for interest	$ 209	$ 208

Description of Business	3 Months Ended
Description of Business	Mar. 31, 2015
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 next-generation medicines for a range of rare and orphan diseases, with a focus on improved therapies for lysosomal storage disorders (“LSDs”). The Company’s lead product candidate is a small molecule that can be used as a monotherapy and in combination with enzyme replacement therapy (“ERT”) for Fabry disorder. The Company’s development programs also include next-generation ERTs for LSDs, including Fabry disorder, Pompe disorder and Mucopolysaccharoidosis Type I (“MPS I”). The Company’s activities since inception have consisted principally of raising capital, establishing facilities, and performing research and development. We have completed two Phase 3 global registration studies of migalastat monotherapy. During the first quarter of 2015, we met with regulatory authorities in Europe and the U.S. to discuss the approval pathways for migalastat as a monotherapy for Fabry patients who have amenable mutations. In Europe, we plan to submit a marketing authorization application (“MAA”) to the European Medicines Agency (“EMA”) in the second quarter of 2015. In the U.S., we plan to submit a new drug application (“NDA”) for accelerated approval (subpart H) with the U.S. Food and Drug Administration (“FDA”) in the second half of 2015. In November 2014, the Company issued a total of 15.9 million shares through a public offering at a price of $6.50 per share, with net proceeds of $97.2 million. The Company expects to use the net proceeds of the offering for investment in the global commercialization infrastructure for migalastat monotherapy for Fabry disorder, the continued clinical development of its product candidates and for other general corporate purposes. The Company had an accumulated deficit of approximately $471.7 million at March 31, 2015 and anticipates incurring losses through the fiscal year ending December 31, 2015 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. The Company believes that its existing cash and cash equivalents and short-term investments will be sufficient to fund the current operating plan into the second half of 2016.

Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2015

Summary of Significant Accounting Policies

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation

The Company has prepared the accompanying unaudited consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10-01 of Regulations S-X. Accordingly, they do not include all of the information and disclosures required by generally accepted accounting principles for complete financial statements. In the opinion of management, the accompanying unaudited financial statements reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s interim financial information.

The accompanying unaudited consolidated financial statements and related notes should be read in conjunction with the Company’s financial statements and related notes as contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014. For a complete description of the Company’s accounting policies, please refer to the Annual Report on Form 10-K for the fiscal year ended December 31, 2014.

Significant Accounting Policies

There have been no material changes to the Company’s significant accounting policies during the three months ended March 31, 2015, as compared to the significant accounting policies disclosed in Note 2 of the Consolidated Financial Statements in the Company’s Annual Report on Form 10-K for the year ended December 31, 2014. However, the following accounting policies are the most critical in fully understanding and evaluating the Company’s financial condition and results of operations.

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 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 is 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.

Recent Accounting Pronouncements

In April 2015, the FASB issued Accounting Standards Update (“ASU”) 2015-03, Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. The amendments in ASU 2015-03 are intended to simplify the presentation of debt issuance costs. These amendments require that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in this ASU. The ASU is effective for financial statements issued for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. We are currently assessing the impact that this standard will have on our consolidated financial statements.

In November 2014, the FASB issued ASU 2014-17, Business Combinations (Topic 805): Pushdown Accounting. The amendments in ASU 2014-17 provide an acquired entity with an option to apply pushdown accounting in its separate financial statements upon occurrence of an event in which an acquirer obtains control of the acquired entity. The ASU is effective on November 18, 2014. After the effective date, an acquired entity can make an election to apply the guidance to future change-in-control events or to its most recent change-in-control event. However, if the financial statements for the period in which the most recent change-in-control event occurred already have been issued or made available to be issued, the application of this guidance would be a change in accounting principle. We are currently assessing the impact that this standard will have on our consolidated financial statements.

In August 2014, the FASB issued ASU 2014-15, Presentation of Financial Statements-Going Concern (Subtopic 205-40): Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern, which defines management’s responsibility to assess an entity’s ability to continue as a going concern, and to provide related footnote disclosures if there is substantial doubt about its ability to continue as a going concern. The pronouncement is effective for annual reporting periods ending after December 15, 2016 with early adoption permitted. The adoption of this guidance is not expected to have a significant impact on our consolidated financial statements.

In May 2014, FASB issued ASU 2014-09, Revenue From Contracts With Customers, that outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. The ASU is based on the principle that an entity should recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The ASU also requires additional disclosure about the nature, amount, timing and uncertainty of revenue and cash flows arising from customer contracts, including significant judgments and changes in judgments and assets recognized from costs incurred to fulfill a contract. Entities have the option of using either a full retrospective or a modified retrospective approach for the adoption of the new standard. The ASU becomes effective for us at the beginning of our 2017 fiscal year; early adoption is not permitted. We are currently assessing the impact that this standard will have on its consolidated financial statements.

Cash, Money Market Funds and Marketable Securities

3 Months Ended

Mar. 31, 2015

Cash, Money Market Funds and Marketable Securities

Cash, Money Market Funds and Marketable Securities

Note 3. Cash, Money Market Funds and Marketable Securities

As of March 31 2015, the Company held $28.8 million in cash and cash equivalents and $122.7 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 accumulated other 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. Investments that have original maturities or greater than 3 months but less than 1 year are classified as short-term and investments with maturities that are greater than 1 year are classified as long-term.

Cash and available-for-sale securities consisted of the following as of March 31, 2015 and December 31, 2014 (in thousands):

	As of March 31, 2015
	Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash balances	$	28,827	$	—	$	—		$	28,827
Corporate debt securities, current portion	107,135		3		(47		)	107,091
Corporate debt securities, non-current portion	2,808		—		(4		)	2,804
Commercial paper	12,486		13		—			12,499
Certificate of deposit	350		—		—			350
	$	151,606	$	16	$	(51	)	$	151,571
Included in cash and cash equivalents	$	28,827	$	—	$	—		$	28,827
Included in marketable securities	122,779		16		(51		)	122,744
Total cash and marketable securities	$	151,606	$	16	$	(51	)	$	151,571

	As of December 31, 2014
	Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash balances	$	24,074	$	—	$	—		$	24,074
Corporate debt securities, current portion	115,862		—		(110		)	115,752
Corporate debt securities, non-current portion	17,508		—		(44		)	17,464
Commercial paper	11,477		22		—			11,499
Certificate of deposit	350		—		—			350
	$	169,271	$	22	$	(154	)	$	169,139
Included in cash and cash equivalents	$	24,074	$	—	$	—		$	24,074
Included in marketable securities	145,197		22		(154		)	145,065
Total cash and marketable securities	$	169,271	$	22	$	(154	)	$	169,139

Unrealized gains and losses are reported as a component of other comprehensive income/ (loss) in the statements of comprehensive loss. For the three months ended March 31, 2015, unrealized holding gain of $97 thousand and for the year ended December 31, 2014, unrealized holding loss of $132 thousand, included in the statement of comprehensive loss.

For the three months ended March 31, 2015 and the year ended December 31, 2014, 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 March 31, 2015 and December 31, 2014 reflect temporary impairments that have not been recognized and have been in a loss position for less than twelve months. The fair value of these available for sale securities in unrealized loss positions was $86.2 million and $129.2 million as of March 31, 2015 and December 31, 2014, respectively.

The Company holds available-for-sale investment securities which are reported at fair value on the Company’s balance sheet. Unrealized holding gains and losses are reported within accumulated other comprehensive income (“AOCI”) in the statements of comprehensive loss. The changes in AOCI associated with the unrealized holding gain on available-for-sale investments during the three months ended March 31, 2015 and March 31,2014 were as follows (in thousands):

	Three Months Ended March 31,
	2015			2014

Balance, beginning	$	(132	)	$	1
Current period changes in fair value, (a)	97			1
Reclassification of earnings, (a)	—			—
Balance, ending	$	(35	)	$	2

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

Acquisition of Callidus Biopharma, Inc.	3 Months Ended
Acquisition of Callidus Biopharma, Inc.	Mar. 31, 2015
Acquisition of Callidus Biopharma, Inc.
Acquisition of Callidus Biopharma, Inc.	Note 4. Acquisition of Callidus Biopharma, Inc. In November 2013, the Company acquired Callidus a privately-held biologics company focused on developing best-in-class ERTs for LSDs and its lead ERT is ATB200 for Pompe disorder in late preclinical development. The acquisition of the Callidus assets and technology compliments Amicus’ CHART™ platform for the development of next generation ERTs. In consideration for the merger, the Company agreed to issue an aggregate of 7.2 million shares of its common stock, par value $0.01 per share, to the former stockholders of Callidus. As of March 31, 2015, approximately 25 thousand shares remain issuable to former Callidus shareholders. In addition, the Company will be obligated to make additional payments to the former stockholders of Callidus upon the achievement by the Company of certain clinical milestones of up to $35 million and regulatory approval milestones of up to $105 million as set forth in the Merger Agreement, provided that the aggregate consideration shall not exceed $130 million. The Company may, at its election, satisfy certain milestone payments identified in the Merger Agreement aggregating $40 million in shares of its Common Stock (calculated based on a price per share equal to the average of the last closing bid price per share for the Common Stock on The NASDAQ Global Market for the ten (10) trading days immediately preceding the date of payment). The milestone payments not permitted to be satisfied in Common Stock (as well as any payments that the Company is permitted to, but chooses not to, satisfy in Common Stock), as a result of the terms of the Merger Agreement, the rules of The NASDAQ Global Market, or otherwise, will be paid in cash. The fair value of the contingent acquisition consideration payments on the acquisition date was $10.6 million and was estimated by applying a probability-based income approach utilizing an appropriate discount rate. This estimation was based on significant inputs that are not observable in the market, referred to as Level 3 inputs. Key assumptions included a discount rate of 11.0% and various probability factors. As of March 31, 2015, the range of outcomes and assumptions used to develop these estimates has changed to better reflect the probability of certain milestone outcomes. (see “— Note 8. Assets and Liabilities Measured at Fair Value”, for additional discussion regarding fair value measurements of the contingent acquisition consideration payable). The Company determined the fair value of the contingent consideration to be $11.7 million at March 31, 2015, resulting in an increase in the contingent consideration payable and related expense of $1.0 million for the three months ended March 31, 2015. The expense in recorded as part of operating expense in the Consolidated Statement of Operations. For further information, see — Note 5 Goodwill & — Note 6 Intangible Assets.

- Definition

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

+ References

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+ Details

Goodwill	3 Months Ended
Goodwill	Mar. 31, 2015
Goodwill
Goodwill	Note 5. Goodwill In connection with the acquisition of Callidus as discussed in “—Note 4. Acquisition of Callidus Biopharma, Inc.”, the Company recognized goodwill of $11.6 million. Goodwill is assessed annually for impairment on October 1 and whenever events or circumstances indicate that the carrying amount of an asset may not be recoverable. If it is determined that the full carrying amount of an asset is not recoverable, an impairment loss is recorded in the amount by which the carrying amount of the asset exceeds its fair value. During the 2014 impairment assessment, it was determined that the goodwill had not been impaired and there were no changes to the goodwill balance in 2014. For the three months ended March 31, 2015, there were no indicators of impairment and the goodwill balance remained at $11.6 million.

Intangible Assets	3 Months Ended
Intangible Assets	Mar. 31, 2015
Intangible Assets
Intangible Assets	Note 6. Intangible Assets In connection with the acquisition of Callidus as discussed in “—Note 4. Acquisition of Callidus Biopharma, Inc.”, the Company recognized In Process Research & Development (“IPR&D”) of $23.0 million. Intangible assets related to IPR&D assets are considered to be indefinite-lived until the completion or abandonment of the associated research and development efforts. During the period the assets are considered indefinite-lived, they will not be amortized but will be tested for impairment on an annual basis on October 1 and between annual tests if the Company becomes aware of any events occurring or changes in circumstances that would indicate a reduction in the fair value of the IPR&D assets below their respective carrying amounts. During the 2014 impairment assessment, it was determined that the IPR&D had not been impaired and there was no change in the IPR&D balance in 2014. For the three months ended March 31, 2015, there were no indicators of impairment and the IPR&D balance remained at $23.0 million.

Stockholders' Equity

3 Months Ended

Mar. 31, 2015

Stockholders' Equity

Stockholders' Equity

Note 7. Stockholders’ Equity

Common Stock and Warrants

As of March 31, 2015, the Company was authorized to issue 125 million 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 that are appropriate for stockholder voting and is entitled to one vote for each share held.

In November 2014, we sold a total of 15.9 million shares of our common stock, par value $0.01 per share, at a public offering price of $6.50 per share. The aggregate offering proceeds were approximately $97.2 million. We expect to use the net proceeds of the offering for investment in the global commercialization infrastructure for migalastat monotherapy for Fabry disorder, the continued clinical development of its product candidates and for other general corporate purposes.

In July 2014, the Company completed a $40 million at the market (“ATM”) equity offering under which the Company sold shares of its common stock, par value $0.01 per shares with Cowen and Company LLC as sales agent. Under the ATM equity program the Company sold 14.3 million shares of common stock resulting in net proceeds of $38.6 million.

The warrants issued in connection with the November 2013 securities and purchase agreement (“SPA”) are classified as equity. As part of the SPA, a total of 7.5 million common shares and 1.6 million warrants were issued at $2.00 per share, for total cash received of $15 million. The warrants are included in stockholder’s equity and were initially measured at fair value of $1.0 million using the Black Scholes valuation model.

Nonqualified Cash Plan

In July 2014, the Board of Directors approved the Company’s Deferral Plan, (the “Deferral Plan”) which provides certain key employees and members of the Board of Directors as selected by the Compensation Committee, with an opportunity to defer the receipt of such participant’s base salary, bonus and director’s fees, as applicable. The Deferral Plan is intended to be a nonqualified deferred compensation plan that complies with the provisions of Section 409A of the Internal Revenue Code of 1986 as amended.

Deferred compensation amounts under the Deferral Plan as of March 31, 2015 were approximately $0.4 million, as compared to $0.1 million on December 31, 2014 and are included in other long term liabilities. As of December 31, 2014, the amounts deferred under the Deferral Plan had not been invested and the investments were subsequently made in the three months ended March 31, 2015. Deferral Plan assets as of March 31, 2015 were $0.4 million are classified as trading securities and recorded at fair value with changes in the investments’ fair value recognized in the period they occur. During the three months ended March 31, 2015, income from the investments was under $1 thousand and unrealized gain/loss was under $1 thousand.

Equity Incentive Plan

Stock Option Grants

The fair value of the stock options granted is estimated on the date of grant using a Black-Scholes option pricing model with the following weighted-average assumptions:

	Three Months ended March 31,
	2015			2014
Expected stock price volatility	77.1		%	81.4		%
Risk free interest rate	1.7		%	2.0		%
Expected life of options (years)	6.25			6.25
Expected annual dividend per share	$	0.00		$	0.00

A summary of the Company’s stock options for the three months ended March 31, 2015 is as follows:

	Number of Shares (in thousands)		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value (in millions)

Balance at December 31, 2014	10,020.7		$	5.02
Options granted	1,415.7		$	9.07
Options exercised	(818.7	)	$	5.02
Options forfeited	(15.0	)	$	2.80
Balance at March 31, 2015	10,602.7		$	5.56	7.3 years	$	57.6
Vested and unvested expected to vest March 31, 2015	9,842.5		$	5.58	7.2 years	$	53.4
Exercisable at March 31, 2015	5,261.0		$	6.30	5.7 years	$	25.3

As of March 31, 2015, the total unrecognized compensation cost related to non-vested stock options granted was $13.4 million and is expected to be recognized over a weighted average period of 3.0 years.

Restricted Stock Units

A summary of non-vested Restricted Stock Units (“RSU”) activity under the Plan for the three months ended March 31, 2015 is as follows:

	Number of Shares (in thousands)	Weighted Average Grant Date Fair Value		Weighted Average Remaining Years	Aggregate Intrinsic Value (in millions)

Non-vested units as of December 31, 2014	955	$	2.28
Granted	—	$	—
Vested	—	$	—
Forfeited	—	$	—

Non-vested units as of March 31, 2015	955	$	2.28	0.49	$	8.2

For the three months ended March 31, 2015, there were no RSUs that vested and all non-vested units are expected to vest over their normal term. As of March 31, 2015, there was $0.7 million of total unrecognized compensation cost related to unvested RSUs with service-based vesting conditions. These costs are expected to be recognized over a weighted average period of 0.49 years.

Compensation Expense Related to Equity Awards

The following table summarizes information related to compensation expense recognized in the statements of operations related to the equity awards (in thousands):

	Three Months
	Ended March 31,
	2015		2014
Equity compensation expense recognized in:
Research and development expense	$	947	$	550
General and administrative expense	1,013		710
Total equity compensation expense	$	1,960	$	1,260

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

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Reference 15: http://www.xbrl.org/2003/role/presentationRef
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Reference 19: http://www.xbrl.org/2003/role/presentationRef
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+ Details

Assets and Liabilities Measured at Fair Value

3 Months Ended

Mar. 31, 2015

Assets and Liabilities Measured at Fair Value

Assets and Liabilities Measured at Fair Value

Note 8. 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 three March 31, 2015. No transfers of assets between Level 1 and Level 2 of the fair value measurement hierarchy occurred during the three months ended March 31, 2015.

Secured Debt

As disclosed in “—Note 9. Short Term Borrowings and Long Term Debt”, the Company has a loan and security agreement with MidCap Financial, Oxford Finance and Silicon Valley Bank (“Term Loan”). The carrying amount of the Company’s borrowings approximates fair value at March 31, 2015. 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.

In connection with the Term Loan, as disclosed in “—Note 9. Short Term Borrowings and Long Term Debt”, the Company recorded a contingent liability of approximately $0.3 million representing the fair value of a contingent payment of up to $0.4 million related to a success fee payable within six months of trigger event, with the trigger event being regulatory acceptance of NDA or MAA submission. This is effective 5 years from the closing of the Term Loan. The success fee payable to the lender was probability adjusted and discounted utilizing an appropriate discount rate and hence classified as Level 3.

Contingent Consideration Payable

The contingent consideration payable resulted from acquisition of Callidus, as discussed in “—Note 4. Acquisition of Callidus Biopharma, Inc.” Our most recent valuation was determined using a probability weighted discounted cash flow valuation approach. Using this approach, expected future cash flows are calculated over the expected life of the agreement, are discounted, and then exercise scenario probabilities are applied. Some of the more significant assumptions used in the valuation include (i) ATB200 clinical forecasts (ii) the probability and timing related to the achievement of certain developmental milestones and (iii) and the discount rate of 11.0% which is a measure of the credit risk associated with settling the liability. The probability of achievement of clinical milestones ranged from 24% to 75% with milestone payment outcomes ranging from $0 to $81 million. The valuation is performed quarterly. Gains and losses are included in the statement of operations. There is no assurance that any of the conditions for the milestone payments will be met.

The contingent consideration payable has been classified as a Level 3 liability as its valuation requires substantial judgment and estimation of factors that are not currently observable in the market. If different assumptions were used for the various inputs to the valuation approach the estimated fair value could be significantly higher or lower than the fair value the Company determined. The Company may be required to record losses in future periods.

Deferred Compensation Plan- Investment and Liability

As disclosed in “—Note 7. Stockholders’ Equity”, the Deferral Plan provides certain key employees and members of the Board of Directors with an opportunity to defer the receipt of such Participant’s base salary, bonus and director’s fees, as applicable. Deferral Plan assets as of March 31, 2015 were $0.4 million are classified as trading securities and recorded at fair value with changes in the investments’ fair value recognized in the period they occur. During the three months ended March 31, 2015, the unrealized gain/loss was under $1 thousand. The Company considers its investments in marketable securities, as available-for-sale and classifies these assets and related liability within the fair value hierarchy as Level 2 primarily utilizing broker quotes in a non-active market for valuation of these securities.

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 March 31, 2015, are identified in the following table (in thousands):

	Level 1		Level 2		Total
Assets:
Cash/ money market funds	$	28,827	$	—	$	28,827
Corporate debt securities	—		109,895		109,895
Commercial paper	—		12,499		12,499
Certificate of deposit	—		350		350
Deferred Compensation Plan Assets	—		398		398
	$	28,827	$	123,142	$	151,969

	Level 1		Level 2		Level 3		Total
Liabilities:
Contingent success fee payable	—		—		370		370
Contingent consideration payable	—		—		11,700		11,700
Deferred Compensation Plan Liability	—		406		—		406
	$	—	$	406	$	12,070	$	12,476

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, 2014, are identified in the following table (in thousands):

	Level 1		Level 2		Total
Assets:
Cash/ money market funds	$	24,074	$	—	$	24,074
Corporate debt securities	—		133,216		133,216
Commercial paper	—		11,499		11,499
Certificate of deposit	—		350		350
Deferred Compensation Plan Assets	—		—		—
	$	24,074	$	145,065	$	169,139

	Level 1		Level 2		Level 3		Total
Liabilities:
Contingent success fee payable	—		—		341		341
Contingent consideration payable	—		—		10,700		10,700
Deferred Compensation Plan Liability	—		124		—		124
	$	—	$	124	$	11,041	$	11,165

- 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 + Details

Short-Term Borrowings and Long-Term Debt	3 Months Ended
Short-Term Borrowings and Long-Term Debt	Mar. 31, 2015
Short-Term Borrowings and Long-Term Debt
Short-Term Borrowings and Long-Term Debt	Note 9. Short-Term Borrowings and Long-Term Debt In December 2013, the Company entered into a credit and security agreement with a lending syndicate consisting of MidCap Funding III, LLC, Oxford Finance LLC, and Silicon Valley Bank . The Company drew $15 million of the aggregate principal amount which bears interest at a rate per annum fixed at 8.5%. The Company made interest-only payments on the Term Loan beginning January 1, 2014 and will continue through April 1, 2015, after which the Company will repay the aggregate principal outstanding balance of the Term Loan in 33 equal monthly installments of principal, plus accrued interest at the applicable rate. The Term Loan matures on December 27, 2017. At March 31, 2015 the total principal amount due under the Term Loan was $15 million. In connection with the Term Loan, the Company recorded a debt discount of $0.8 million at December 31, 2013 which consists of payments to be made and a contingent payable to the lenders. These payments include a debt facility fee of $0.1 million which was paid on the date of the First Tranche, $0.4 million exit fee that will be payable upon repayment of the term loan and $0.4 million representing the fair value of a contingent payment of up to $0.4 million related to a success fee payable within six months of trigger event, with the trigger event being regulatory acceptance of NDA or MAA submission. This is effective 5 years from the closing of the Term Loan. The success fee payable to the lender was probability adjusted and discounted utilizing an appropriate discount rate and is shown as a current liability on the Company’s consolidated balance sheet.

Collaborative Agreements

3 Months Ended

Mar. 31, 2015

Collaborative Agreements

Collaborative Agreements

Note 10. Collaborative Agreements

GSK

In November 2013, Amicus entered into the Revised Agreement with GlaxoSmithKline (“GSK”), pursuant to which Amicus has obtained global rights to develop and commercialize migalastat as a monotherapy and in combination with ERT for Fabry disorder. The Revised Agreement amends and replaces in its entirety the Expanded Agreement entered into between Amicus and GSK in July 2012. Under the terms of the Revised Agreement, there was no upfront payment from Amicus to GSK. For migalastat monotherapy, GSK is eligible to receive post-approval and sales-based milestones up to $40 million, as well as tiered royalties in the mid-teens in eight major markets outside the U.S.

Under the terms of the Revised Agreement, GSK will no longer jointly fund development costs for all formulations of migalastat.

Biogen

In September 2013, the Company entered into a license and collaboration agreement (the “Biogen Agreement”) with Biogen Idec (“Biogen”) to discover, develop and commercialize novel small molecules for the treatment of Parkinson’s disorder. Under terms of the agreement, the Company and Biogen collaborated in the discovery of a new class of small molecules that target the GCase enzyme, for further development and commercialization by Biogen. Biogen was responsible for funding all discovery, development, and commercialization activities. In addition the Company was reimbursed for all full-time employees working on the project as part of a cost sharing arrangement. The Company was also eligible to receive development and regulatory milestones, as well as modest royalties in global net sales.

In accordance with the revenue recognition guidance related to reimbursement of research and development expenses, the Company identified all deliverables at the inception of the agreement. As the Company has not commenced its planned principal operations (i.e. selling commercial products) the Company is only performing development of its compounds, and therefore, development activities are part of the Company’s ongoing central operations. Additionally, the Company has the following accounting policies:

Research and development expenses related to a collaboration agreement will be recorded on a gross basis in the income statement and not presented net of any reimbursement received from a collaboration agreement; and

The reimbursement of research and development expenses from a collaborator will be recognized in the income statement as “Research Revenue” for the period in which the research activity occurred.

For the three months ended March 31, 2014, the Company recognized $0.5 million in Research Revenue for work performed under the cost sharing arrangement of the Biogen Agreement.

In September 2014, the Company and Biogen concluded their research collaboration. The Company’s most advanced Parkinson’s candidate is AT3375, which was developed outside the collaboration and is wholly-owned by the Company.

Restructuring Charges

3 Months Ended

Mar. 31, 2015

Restructuring Charges

Restructuring Charges

Note 11. Restructuring Charges

In December 2013, the Company initiated and completed a facilities consolidation effort, closing one of its leased locations in San Diego, CA. The Company recorded a charge of $0.7 million related to the net present value of the net future minimum lease payments at the cease-use date.

The following table summarizes the restructuring charges and utilization for the three months ended March 31, 2015 (in thousands):

		Balance as of December 31, 2014			Charges			Cash Payments			Adjustments			Balance as of March 31, 2015
Facilities consolidation		$	283		$	—		$	(59	)	$	10		$	234

Subsequent Events	3 Months Ended
Subsequent Events	Mar. 31, 2015
Subsequent Events
Subsequent Events	Note 12. Subsequent Events The Company evaluated events that occurred subsequent to March 31, 2015 and there were no material recognized or non-recognized subsequent events during this period.

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

3 Months Ended

Mar. 31, 2015

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

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

Note 13. 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 has 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:

	Three Months Ended March 31,
(In thousands, except per share amounts)	2015			2014
Historical
Numerator:
Net loss attributable to common stockholders	$	(24,288	)	$	(15,943	)

Denominator
Weighted average common shares outstanding — basic and diluted	95,743,416			64,353,952

Dilutive common stock equivalents would include the dilutive effect of common stock options, restricted stock units and warrants for common stock equivalents. Potentially dilutive common stock equivalents were excluded from the diluted earnings per share denominator for all periods because of their anti-dilutive effect. The table below presents potential shares of common stock that were excluded from the computation as they were anti-dilutive using the treasury stock method (in thousands):

	As of March 31,
	2015	2014
Options to purchase common stock	10,603	9,660
Outstanding warrants, convertible to common stock	1,600	1,600
Unvested restricted stock units	955	—

Total number of potentially issuable shares	13,158	11,260

Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2015

Summary of Significant Accounting Policies

Basis of Presentation

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

Recent Accounting Pronouncements

- Definition

Disclosure of accounting policy for revenue recognition. If the entity has different policies for different types of revenue transactions, the policy for each material type of transaction is generally disclosed. If a sales transaction has multiple element arrangements (for example, delivery of multiple products, services or the rights to use assets) the disclosure may indicate the accounting policy for each unit of accounting as well as how units of accounting are determined and valued. The disclosure may encompass important judgment as to appropriateness of principles related to recognition of revenue. The disclosure also may indicate the entity's treatment of any unearned or deferred revenue that arises from the transaction.

+ References + Details

Cash, Money Market Funds and Marketable Securities (Tables)

3 Months Ended

Mar. 31, 2015

Cash, Money Market Funds and Marketable Securities

Schedule of cash and available-for-sale securities

Cash and available-for-sale securities consisted of the following as of March 31, 2015 and December 31, 2014 (in thousands):

	As of March 31, 2015
	Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash balances	$	28,827	$	—	$	—		$	28,827
Corporate debt securities, current portion	107,135		3		(47		)	107,091
Corporate debt securities, non-current portion	2,808		—		(4		)	2,804
Commercial paper	12,486		13		—			12,499
Certificate of deposit	350		—		—			350
	$	151,606	$	16	$	(51	)	$	151,571
Included in cash and cash equivalents	$	28,827	$	—	$	—		$	28,827
Included in marketable securities	122,779		16		(51		)	122,744
Total cash and marketable securities	$	151,606	$	16	$	(51	)	$	151,571

	As of December 31, 2014
	Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash balances	$	24,074	$	—	$	—		$	24,074
Corporate debt securities, current portion	115,862		—		(110		)	115,752
Corporate debt securities, non-current portion	17,508		—		(44		)	17,464
Commercial paper	11,477		22		—			11,499
Certificate of deposit	350		—		—			350
	$	169,271	$	22	$	(154	)	$	169,139
Included in cash and cash equivalents	$	24,074	$	—	$	—		$	24,074
Included in marketable securities	145,197		22		(154		)	145,065
Total cash and marketable securities	$	169,271	$	22	$	(154	)	$	169,139

Schedule of changes in AOCI associated with the unrealized holding gain on available-for-sale investments

The changes in AOCI associated with the unrealized holding gain on available-for-sale investments during the three months ended March 31, 2015 and March 31,2014 were as follows (in thousands):

	Three Months Ended March 31,
	2015			2014

Balance, beginning	$	(132	)	$	1
Current period changes in fair value, (a)	97			1
Reclassification of earnings, (a)	—			—
Balance, ending	$	(35	)	$	2

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

Stockholders' Equity (Tables)

3 Months Ended

Mar. 31, 2015

Stockholders' Equity

Schedule of fair value weighted-average assumptions

	Three Months ended March 31,
	2015			2014
Expected stock price volatility	77.1		%	81.4		%
Risk free interest rate	1.7		%	2.0		%
Expected life of options (years)	6.25			6.25
Expected annual dividend per share	$	0.00		$	0.00

Summary of stock options

	Number of Shares (in thousands)		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value (in millions)

Balance at December 31, 2014	10,020.7		$	5.02
Options granted	1,415.7		$	9.07
Options exercised	(818.7	)	$	5.02
Options forfeited	(15.0	)	$	2.80
Balance at March 31, 2015	10,602.7		$	5.56	7.3 years	$	57.6
Vested and unvested expected to vest March 31, 2015	9,842.5		$	5.58	7.2 years	$	53.4
Exercisable at March 31, 2015	5,261.0		$	6.30	5.7 years	$	25.3

Summary of information on the Company's restricted stock

	Number of Shares (in thousands)	Weighted Average Grant Date Fair Value		Weighted Average Remaining Years	Aggregate Intrinsic Value (in millions)

Non-vested units as of December 31, 2014	955	$	2.28
Granted	—	$	—
Vested	—	$	—
Forfeited	—	$	—

Non-vested units as of March 31, 2015	955	$	2.28	0.49	$	8.2

Summary of the stock-based compensation expense recognized in the statements of operations

The following table summarizes information related to compensation expense recognized in the statements of operations related to the equity awards (in thousands):

	Three Months
	Ended March 31,
	2015		2014
Equity compensation expense recognized in:
Research and development expense	$	947	$	550
General and administrative expense	1,013		710
Total equity compensation expense	$	1,960	$	1,260

Assets and Liabilities Measured at Fair Value (Tables)

3 Months Ended

Mar. 31, 2015

Assets and Liabilities Measured at Fair Value

Summary of assets and liabilities subject to fair value measurements

	Level 1		Level 2		Total
Assets:
Cash/ money market funds	$	28,827	$	—	$	28,827
Corporate debt securities	—		109,895		109,895
Commercial paper	—		12,499		12,499
Certificate of deposit	—		350		350
Deferred Compensation Plan Assets	—		398		398
	$	28,827	$	123,142	$	151,969

	Level 1		Level 2		Level 3		Total
Liabilities:
Contingent success fee payable	—		—		370		370
Contingent consideration payable	—		—		11,700		11,700
Deferred Compensation Plan Liability	—		406		—		406
	$	—	$	406	$	12,070	$	12,476

	Level 1		Level 2		Total
Assets:
Cash/ money market funds	$	24,074	$	—	$	24,074
Corporate debt securities	—		133,216		133,216
Commercial paper	—		11,499		11,499
Certificate of deposit	—		350		350
Deferred Compensation Plan Assets	—		—		—
	$	24,074	$	145,065	$	169,139

	Level 1		Level 2		Level 3		Total
Liabilities:
Contingent success fee payable	—		—		341		341
Contingent consideration payable	—		—		10,700		10,700
Deferred Compensation Plan Liability	—		124		—		124
	$	—	$	124	$	11,041	$	11,165

Restructuring Charges (Tables)

3 Months Ended

Mar. 31, 2015

Restructuring Charges

Summary of restructuring charges and utilization

The following table summarizes the restructuring charges and utilization for the three months ended March 31, 2015 (in thousands):

		Balance as of December 31, 2014			Charges			Cash Payments			Adjustments			Balance as of March 31, 2015
Facilities consolidation		$	283		$	—		$	(59	)	$	10		$	234

Basic and Diluted Net Loss Attributable to Common Stockholders per Common Share (Tables)

3 Months Ended

Mar. 31, 2015

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

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

	Three Months Ended March 31,
(In thousands, except per share amounts)	2015			2014
Historical
Numerator:
Net loss attributable to common stockholders	$	(24,288	)	$	(15,943	)

Denominator
Weighted average common shares outstanding — basic and diluted	95,743,416			64,353,952

Schedule of potential shares of common stock that were excluded from the computation as they were anti-dilutive using the treasury stock method

The table below presents potential shares of common stock that were excluded from the computation as they were anti-dilutive using the treasury stock method (in thousands):

	As of March 31,
	2015	2014
Options to purchase common stock	10,603	9,660
Outstanding warrants, convertible to common stock	1,600	1,600
Unvested restricted stock units	955	—

Total number of potentially issuable shares	13,158	11,260

Description of Business - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	1 Months Ended
	Nov. 30, 2014	Mar. 31, 2015	Dec. 31, 2014
Corporate Information, Status of Operations and Management Plans
Accumulated deficit		$ 471,736	$ 447,448
Shares Issued, Price Per Share	$ 6.50
Common stock issued (in shares)	15.9
Proceeds from the issuance of common stock (in dollars)	$ 97,200

Cash, Money Market Funds and Marketable Securities (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013
Cash, Money Market Funds, and Marketable Securities
Cash and cash equivalents, Amortized Cost	$ 28,827	$ 27,533	$ 24,074	$ 43,640
Cash and cash equivalents, Fair Value	28,827		24,074
Marketable securities, Amortized Cost	122,779		145,197
Unrealized Gain	16		22
Unrealized Loss	(51)		(154)
Marketable securities, Fair Value	122,744		145,065
Cash and marketable securities, Amortized Cost	151,606		169,271
Cash and marketable securities, Fair Value	151,571		169,139
Available-for-sale investments
Realized gain (loss) on securities available-for-sale	0		0
Fair value of available for sale securities in unrealized loss positions	86,200		129,200
Changes in AOCI associated with the unrealized holding gain on available-for-sale investments
Balance, beginning	(132)	1	1
Current period changes in fair value	97	1	132
Balance, ending	(35)	$ 2	(132)
Short term corporate debt securities
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	107,135		115,862
Unrealized Gain	3
Unrealized Loss	(47)		(110)
Marketable securities, Fair Value	107,091		115,752
Long term corporate debt securities
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	2,808		17,508
Unrealized Loss	(4)		(44)
Marketable securities, Fair Value	2,804		17,464
Commercial paper
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	12,486		11,477
Unrealized Gain	13		22
Marketable securities, Fair Value	12,499		11,499
Certificate of deposit
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	350		350
Marketable securities, Fair Value	$ 350		$ 350

Acquisition of Callidus Biopharma, Inc. (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	1 Months Ended	3 Months Ended
	Nov. 30, 2013	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Nov. 30, 2014
Acquisition of Callidus Biopharma, Inc.
Common stock, par value (in dollars per share)		$ 0.01		$ 0.01	$ 0.01
Contingent consideration payable		$ 11,700		$ 10,700
Changes in fair value of contingent consideration payable		$ 1,000	$ 505
Callidus
Acquisition of Callidus Biopharma, Inc.
Common stock issued on acquisition (in shares)	7,200
Common stock, par value (in dollars per share)	$ 0.01
Shares issued		25
Maximum merger consideration to be transferred	$ 130,000
Milestone payment that can be settled in equity	$ 40,000
Number of trading days immediately preceding the date of payment on basis of which issue price will be determined	10 days
Discount rate (as a percent)	11.00%	11.00%
Contingent consideration payable	$ 10,600	$ 11,700
Changes in fair value of contingent consideration payable		$ 1,000
Callidus \| Maximum
Acquisition of Callidus Biopharma, Inc.
Additional payment to be made upon achievement of clinical milestone	35,000
Additional payment to be made upon achievement of regulatory approval	$ 105,000

Goodwill (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
Goodwill (Details) - USD ($) $ in Thousands	Nov. 30, 2013	Mar. 31, 2015	Dec. 31, 2014
Changes in goodwill
Change in goodwill related to the acquisition of Callidus	$ 11,600
Change in goodwill		$ 0	$ 0
Goodwill		$ 11,613	$ 11,613

Intangible Assets (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
Intangible Assets (Details) - USD ($) $ in Thousands	Nov. 30, 2013	Mar. 31, 2015	Dec. 31, 2014
Changes in IPR&D
In-process research & development		$ 23,000	$ 23,000
Callidus
Changes in IPR&D
IPR&D related to the acquisition of Callidus	$ 23,000
In-process research & development		23,000
Impairment of IPR&D		$ 0	$ 0

Stockholders' Equity (Details) $ / shares in Units, $ in Millions	1 Months Ended
	Nov. 30, 2014 USD ($) $ / shares shares	Jul. 31, 2014 USD ($)	Mar. 31, 2014 USD ($) $ / shares shares	Nov. 30, 2013 USD ($) $ / shares shares	Mar. 31, 2015 item $ / shares shares	Dec. 31, 2014 $ / shares shares
Stockholders' Equity
Authorized number of shares of common stock \| shares					125,000,000	125,000,000
Voting right for each share held, number \| item					1
Collaborative Agreements
Common stock issued (in shares) \| shares	15,900,000
Aggregate offering proceeds from issuance of common stock \| $		$ 40.0
Common stock, par value (in dollars per share) \| $ / shares	$ 0.01				$ 0.01	$ 0.01
Net proceeds from the issuance of common stock \| $	$ 97.2
Price per unit (in dollars per share) \| $ / shares	$ 6.50
SPA
Collaborative Agreements
Stock issued from collaboration agreement (in shares) \| shares				7,500,000
Common stock issued (in shares) \| shares				1,600,000
Price per unit (in dollars per share) \| $ / shares				$ 2.00
Proceeds received from private placement \| $				$ 15.0
SPA \| Warrants
Collaborative Agreements
Value of the warrants \| $				$ 1.0
Cowen and Company, LLC \| Sales Agreement
Collaborative Agreements
Common stock, par value (in dollars per share) \| $ / shares			$ 0.01
Cowen and Company, LLC \| Sales Agreement \| Maximum
Collaborative Agreements
Common stock issued (in shares) \| shares			14,300,000
Net proceeds from stock issued at ATM transactions \| $			$ 38.6

Stockholders' Equity (Details 2) - USD ($) $ in Thousands	3 Months Ended
Stockholders' Equity (Details 2) - USD ($) $ in Thousands	Mar. 31, 2015	Mar. 31, 2014
Equity compensation expense
Total equity compensation expense	$ 1,960	$ 1,260
Research and development expense
Equity compensation expense
Total equity compensation expense	947	550
General and administrative expense
Equity compensation expense
Total equity compensation expense	$ 1,013	$ 710

Stockholders' Equity (Details 3) - USD ($)	3 Months Ended
Stockholders' Equity (Details 3) - USD ($)	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Stockholders' Equity
Equity compensation expense	$ 1,960,000	$ 1,260,000
Fair value weighted-average assumptions:
Expected life of options	5 months 27 days
Aggregate Intrinsic Value
Unrecognized compensation cost related to unvested restricted stock awards (in dollars)	$ 700,000
Nonqualified Cash Plan
Stockholders' Equity
Deferred compensation liability, noncurrent	400,000		$ 100,000
Trading securities	400,000
Common stock options
Stockholders' Equity
Total unrecognized compensation cost related to non-vested stock options granted (in dollars)	$ 13,400,000
Period of recognition compensation cost	3 years
Fair value weighted-average assumptions:
Expected stock price volatility (as a percent)	77.10%	81.40%
Risk free interest rate (as a percent)	1.70%	2.00%
Expected life of options	6 years 3 months	6 years 3 months
Expected annual dividend per share (in dollars per share)	$ 0.00	$ 0.00
Number of Shares
Balance at the beginning of the period (in shares)	10,020,700
Options granted (in shares)	1,415,700
Options exercised (in shares)	(818,700)
Options forfeited (in shares)	(15,000)
Balance at the end of the period (in shares)	10,602,700
Vested and unvested expected to vest at the end of the period (in shares)	9,842,500
Exercisable at the end of the period (in shares)	5,261,000
Weighted Average Exercise Price
Balance at the beginning of the period (in dollars per share)	$ 5.02
Options granted (in dollars per share)	9.07
Options exercised (in dollars per share)	5.02
Options forfeited (in dollars per share)	2.80
Balance at the end of the period (in dollars per share)	5.56
Vested and unvested expected to vest at the end of the period (in dollars per share)	5.58
Exercisable at the end of the period (in dollars per share)	$ 6.30
Weighted Average Remaining Contractual Life
Balance at the end of the period	7 years 3 months 18 days
Vested and unvested expected to vest at the end of the period	7 years 2 months 12 days
Exercisable at the end of the period	5 years 8 months 12 days
Aggregate Intrinsic Value
Aggregate intrinsic value of options outstanding (in dollars)	$ 57,600
Aggregate intrinsic value of options vested and unvested expected to vest (in dollars)	53,400
Aggregate intrinsic value of options exercisable (in dollars)	$ 25,300
Restricted stock units (RSUs)
Stockholders' Equity
Period of recognition compensation cost	5 months 27 days
Number of Shares
Balance at the beginning of the period (in shares)	955,000
Balance at the end of the period (in shares)	955,000
Weighted Average Exercise Price
Balance at the beginning of the period (in dollars per share)	$ 2.28
Balance at the end of the period (in dollars per share)	$ 2.28
Aggregate Intrinsic Value
Aggregate intrinsic value, nonvested (in dollars)	$ 8,200,000
Options vested	0
Maximum \| Nonqualified Cash Plan
Stockholders' Equity
Income from investments	$ 1,000
Unrealized gain/loss	$ 1,000

Assets and Liabilities Measured at Fair Value (Details) $ in Thousands	1 Months Ended	3 Months Ended
	Nov. 30, 2013 USD ($)	Mar. 31, 2015 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Assets and Liabilities Measured at Fair Value
Transfer of assets from Level 1 to Level 2		$ 0
Transfer of assets from Level 2 to Level 1		0
Contingent consideration payable
Change in fair value		1,000	$ 505
Assets:
Cash/money market funds		28,827	$ 27,533	$ 24,074	$ 43,640
Liabilities:
Contingent consideration payable		11,700		10,700
Callidus
Contingent consideration payable
Change in fair value		1,000
Liabilities:
Contingent consideration payable	$ 10,600	$ 11,700
Discount rate (as a percent)	11.00%	11.00%
Minimum \| Callidus
Contingent consideration payable
Milestone achievement probability (as a percent)		24
Milestone payment		$ 0
Maximum
Contingent consideration payable
Unrealized gain (loss) on securities		$ 1
Maximum \| Callidus
Contingent consideration payable
Milestone achievement probability (as a percent)		75
Milestone payment		$ 81,000
Level 1
Assets:
Fair value of assets		28,827		24,074
Level 1 \| Cash/money market funds
Assets:
Cash/money market funds		28,827		24,074
Level 2
Assets:
Fair value of assets		123,142		145,065
Deferred Compensation Plan Assets		398
Liabilities:
Deferred Compensation Plan Liability		406		124
Fair value of liabilities		406		124
Level 2 \| Corporate debt securities
Assets:
Fair value of assets		109,895		133,216
Level 2 \| Commercial paper
Assets:
Fair value of assets		12,499		11,499
Level 2 \| Certificate of deposit
Assets:
Fair value of assets		350		350
Level 3
Financial assets and liabilities subject to fair value measurements
Contingent success fee payable		370		341
Liabilities:
Contingent success fee payable		370		341
Contingent consideration payable		11,700		10,700
Fair value of liabilities		12,070		11,041
Total
Financial assets and liabilities subject to fair value measurements
Contingent success fee payable		370		341
Assets:
Fair value of assets		151,969		169,139
Deferred Compensation Plan Assets		398
Liabilities:
Contingent success fee payable		370		341
Contingent consideration payable		11,700		10,700
Deferred Compensation Plan Liability		406		124
Fair value of liabilities		12,476		11,165
Total \| Cash/money market funds
Assets:
Cash/money market funds		28,827		24,074
Total \| Corporate debt securities
Assets:
Fair value of assets		109,895		133,216
Total \| Commercial paper
Assets:
Fair value of assets		12,499		11,499
Total \| Certificate of deposit
Assets:
Fair value of assets		350		$ 350
2013 Loan Agreement
Financial assets and liabilities subject to fair value measurements
Fair value of contingent payment		$ 300
Period of trigger event within which success fee is payable		6 months
Period of effectiveness of trigger event from closing of loan		5 years
2013 Loan Agreement \| Level 3 \| Maximum
Financial assets and liabilities subject to fair value measurements
Contingent success fee payable		$ 400
Liabilities:
Contingent success fee payable		$ 400

Short-Term Borrowings and Long-Term Debt (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2015 USD ($) item	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Level 3
Short-Term Borrowings and Long-Term Debt
Contingent success fee payable	$ 370	$ 341
2013 Loan Agreement
Short-Term Borrowings and Long-Term Debt
Fixed interest rate (as a percent)	8.50%
Long-term portion	$ 15,000		$ 15,000
Less debt discount			$ 800
Number of equal monthly installments for repayment of debt \| item	33
Debt facility fee	$ 100
Contingent exit fee payable	400
Fair value of contingent payment	$ 300
Period of trigger event within which success fee is payable	6 months
Period of effectiveness of trigger event from closing of loan	5 years
2013 Loan Agreement \| Maximum \| Level 3
Short-Term Borrowings and Long-Term Debt
Contingent success fee payable	$ 400

Collaborative Agreements (Details) $ in Thousands	1 Months Ended	3 Months Ended
Collaborative Agreements (Details) $ in Thousands	Nov. 30, 2013 USD ($) item	Mar. 31, 2015 USD ($)	Mar. 31, 2014 USD ($)
Collaborative Agreements
Research revenue for work performed under cost sharing arrangement			$ 456
GSK \| Revised Agreement
Collaborative Agreements
Upfront payment received	$ 0
Number of major markets outside the U.S. from whom parties to contractual arrangement is eligible to receive post-approval and sales-based milestones \| item	8
GSK \| Revised Agreement \| Maximum
Collaborative Agreements
Potential milestone payments upon achievement of post-approval and sales-based milestones	$ 40,000
Biogen Idec
Collaborative Agreements
Research revenue for work performed under cost sharing arrangement		$ 500

Restructuring Charges (Details) $ in Thousands	1 Months Ended	3 Months Ended
Restructuring Charges (Details) $ in Thousands	Dec. 31, 2013 item	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Mar. 31, 2014 USD ($)
Summary of restructuring charges and utilization
Charges		$ (10)		$ 8
Facilities consolidation
Restructuring charges
Number of subleased locations that were closed in consolidation \| item	1
Lease payments			$ 700
Summary of restructuring charges and utilization
Balance at the beginning of the period		283
Cash payments		(59)
Adjustments		10
Balance at the end of the period		$ 234	$ 283

Basic and Diluted Net Loss Attributable to Common Stockholders per Common Share (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Antidilutive securities
Antidilutive securities excluded from computation of diluted earnings per share (in shares)	13,158,000	11,260,000
Numerator:
Net loss attributable to common stockholders	$ (24,288)	$ (15,943)
Denominator
Weighted average common shares outstanding - basic and diluted	95,743,416	64,353,952
Common stock options
Antidilutive securities
Antidilutive securities excluded from computation of diluted earnings per share (in shares)	10,603,000	9,660,000
Warrants
Antidilutive securities
Antidilutive securities excluded from computation of diluted earnings per share (in shares)	1,600,000	1,600,000
Restricted stock units (RSUs)
Antidilutive securities
Antidilutive securities excluded from computation of diluted earnings per share (in shares)	955,000