View Filing Data

Document and Entity Information - shares	9 Months Ended
Sep. 30, 2017	Oct. 31, 2017
Document and Entity Information
Entity Registrant Name	AMICUS THERAPEUTICS INC
Entity Central Index Key	0001178879
Document Type	10-Q
Document Period End Date	Sep. 30, 2017
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		166,269,300
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q3

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 64,133	$ 187,026
Investments in marketable securities, current portion	347,388	143,325
Accounts receivable	5,974	1,304
Inventories	7,272	3,416
Prepaid expenses and other current assets	6,246	4,993
Total current assets	431,013	340,064
Investments in marketable securities	15,109
Property and equipment, less accumulated depreciation of $13,273 and $12,495 at September 30, 2017 and December 31, 2016, respectively	9,641	9,816
In-process research & development	23,000	486,700
Goodwill	197,797	197,797
Other non-current assets	4,219	2,468
Total Assets	680,779	1,036,845
Current liabilities:
Accounts payable, accrued expenses, and other current liabilities	53,709	41,008
Deferred reimbursements, current portion	6,250	13,850
Contingent consideration payable, current portion	8,200	56,101
Total current liabilities	68,159	110,959
Deferred reimbursements	16,906	21,906
Convertible notes	161,635	154,464
Contingent consideration payable	12,900	213,621
Deferred income taxes	9,186	173,771
Other non-current liability	2,313	1,973
Commitments and contingencies
Stockholders' equity:
Common stock, $0.01 par value, 250,000,000 shares authorized, 165,491,141 and 142,691,986 shares issued and outstanding at September 30, 2017 and December 31, 2016, respectively	1,707	1,480
Additional paid-in capital	1,387,767	1,120,156
Accumulated other comprehensive loss:
Foreign currency translation adjustment	(1,367)	1,945
Unrealized gain on available-for-sale securities	(101)	102
Warrants	16,076	16,076
Accumulated deficit	(994,402)	(779,608)
Total stockholders' equity	409,680	360,151
Total Liabilities and Stockholders' Equity	$ 680,779	$ 1,036,845

Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenue:
Net product sales	$ 10,874	$ 2,127	$ 22,201	$ 2,127
Cost of goods sold	1,790	344	3,626	344
Gross Profit	9,084	1,783	18,575	1,783
Operating Expenses:
Research and development	40,641	32,457	103,502	74,163
Selling, general and administrative	21,647	17,469	60,090	52,470
Changes in fair value of contingent consideration payable	(244,250)	(4,110)	(238,622)	9,228
Loss on impairment of assets	465,427		465,427
Restructuring charges		11		69
Depreciation	851	896	2,486	2,336
Total operating expenses	284,316	46,723	392,883	138,266
Loss from operations	(275,232)	(44,940)	(374,308)	(136,483)
Other income (expenses):
Interest income	1,190	460	2,702	1,098
Interest expense	(4,351)	(1,517)	(12,820)	(3,517)
Other income (expense)	2,044	(910)	5,054	(3,199)
Loss before income tax benefit	(276,349)	(46,907)	(379,372)	(142,101)
Income tax benefit	164,683	253	164,578	706
Net loss attributable to common stockholders	$ (111,666)	$ (46,654)	$ (214,794)	$ (141,395)
Net loss attributable to common stockholders per common share - basic and diluted	$ (0.69)	$ (0.33)	$ (1.44)	$ (1.07)
Weighted-average common shares outstanding - basic and diluted	160,796,841	140,656,109	148,963,864	131,675,690

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Operating activities
Net loss	$ (214,794)	$ (141,395)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of debt discount and deferred financing	7,179	1,744
Depreciation	2,486	2,336
Stock-based compensation	17,067	13,087
Charges to research expense for stock issued in asset acquisition		4,607
Restructuring charges		69
Loss on impairment	465,427
(Gain)/ Loss on disposal of asset	(8)	17
Change in fair value of derivative liability	(265)	324
Non-cash changes in the fair value of contingent consideration payable	(238,622)	9,228
Foreign currency remeasurement (gain)/ loss	(4,932)	2,207
Non-cash deferred taxes and other tax benefits	(164,585)	(706)
Changes in operating assets and liabilities:
Accounts receivable	(4,288)	(863)
Inventories	(3,386)	(3,505)
Prepaid expenses and other current assets	(3,358)	(2,803)
Other non-current assets	(713)	(660)
Account payable and accrued expenses	13,037	(2,920)
Non-current liabilities	637	684
Deferred reimbursements	(12,600)
Net cash used in operating activities	(141,718)	(118,549)
Investing activities
Sale and redemption of marketable securities	230,981	165,495
Purchases of marketable securities	(450,358)	(199,829)
Purchases of property and equipment	(3,398)	(5,520)
Net cash used in investing activities	(222,775)	(39,854)
Financing activities
Proceeds from issuance of common stock, net of issuance costs	243,036	97,068
Proceeds from unsecured loan agreement		30,000
Payment of capital leases	(212)	(118)
Payment of contingent consideration	(10,000)	(5,000)
Purchase of vested restricted stock units	(1,067)	(1,010)
Proceeds from exercise of stock options	8,841	1,456
Payment of deferred financing fees	(28)
Net cash provided by financing activities	240,570	122,396
Effect of exchange rate changes on cash and cash equivalents	1,030	(363)
Net decrease in cash and cash equivalents	(122,893)	(36,370)
Cash and cash equivalents at beginning of year/ period	187,026	69,485
Cash and cash equivalents at end of year/period	64,133	33,115
Supplemental disclosures of cash flow information
Cash paid during the period for interest	$ 3,662	284
Contingent consideration resolution in shares		6,115
Capital expenditures funded by capital lease borrowings		$ 850

Description of Business	9 Months Ended
Description of Business	Sep. 30, 2017
Description of Business
Description of Business	Note 1. Description of Business Corporate Information, Status of Operations, and Management Plans Amicus Therapeutics, Inc. (the “Company”) is a global patient-focused biotechnology company engaged in the discovery, development and commercialization of a diverse set of novel treatments for patients living with devastating rare and orphan diseases. The Company’s lead product, migalastat HCl, is a small molecule that can be used as a monotherapy and in combination with enzyme replacement therapy (“ERT”) for Fabry disease. Migalastat was approved for use in the European Union (“EU”) in May 2016 under the brand name Galafold™ as a first-line therapy for long-term treatment of adults and adolescents aged 16 years and older with a confirmed diagnosis of Fabry disease and who have an amenable mutation. Additionally, based on a series of discussions with and written communication received from the U.S. Food and Drug Administration (the “FDA”), the FDA has informed the Company that it may now submit a New Drug Application (“NDA”) for migalastat. An additional Phase 3 study previously requested by the FDA to assess Gastrointestinal (“GI”) symptoms is no longer required before an NDA submission. The Company is preparing the NDA submission under Subpart H, which provides for accelerated approval, and plans to submit an NDA to the FDA for migalastat for Fabry disease in the fourth quarter of 2017. The Company is also investigating a novel treatment paradigm ATB200/AT2221 in patients with Pompe disease, an inherited lysosomal storage disorder caused by an enzyme deficiency that leads to accumulation of glycogen (disease substrate) in cells. In October 2017, the Company announced additional positive results from our global Phase 1/2 clinical study (ATB200-02) to investigate ATB200/AT2221 in patients with Pompe disease. Consistent with previous results, patients who completed six months of treatment with ATB200/AT2221 showed improvements in six-minute walk test (“6MWT”) distance and other measures of motor function, stability or increases in forced vital capacity (“FVC”), and further reductions in biomarkers of muscle damage and disease substrate, with consistent results reported in initial patients who completed nine months of treatment. On September 21, 2017, the Company announced that the FDA granted orphan drug designation to ATB200/AT2221. The Company was previously developing SD-101in late-stage development as a potential first-to-market therapy for the chronic, rare connective tissue disorder Epidermolysis Bullosa (“EB”). On September 13, 2017, the Company reported that top-line data from the randomized, double-blind, placebo-controlled Phase 3 clinical study (“ESSENCE” or “SD-005”) to assess the efficacy and safety of the novel topical wound-healing agent SD-101 did not meet the primary endpoints or secondary endpoints in participants with EB. The Company plans to further analyze and share the Phase 3 ESSENCE results with key stakeholders in the EB community including physicians, patient organizations and regulators. In the interim, in consultation with their physicians, participants in the ongoing extension studies (SD-004 and -006) will have the opportunity to continue being treated with SD-101. Based on the top-line data, the Company has no current plans to invest in any additional clinical studies or commercial preparation activities for SD-101. This event led the Company to assess the carrying amount of the program’s tangible and intangible assets against their respective fair values. Based on the assessment, the Company recognized a loss on impairment of intangible assets in the amount of $463.7 million and $1.7 million in fixed assets recorded within Loss on Impairment of Assets within the Consolidated Statements of Operation. Since the study did not meet the primary and secondary endpoints, the Company has concluded that they will not make the potential milestone payments indicated in the Asset Purchase Agreement to the former Scioderm holders. Accordingly, the Company recognized a gain of $254.7 million in Changes in Fair Value of Contingent Consideration Payable in the Consolidated Statements of Operation for the three months ended September 30, 2017 in order to decrease the liability to zero. The Company also recognized $0.4 million in selling, general and administrative costs and $8.1 million in research and development expenses related to the wind-down of operations for the Phase 3 ESSENCE study and ongoing extension studies SD-004 and SD-006 in the third quarter of 2017. See “—Note 4. Goodwill and IPR&D” for more details. The Company is also investigating preclinical and discovery programs in other rare and devastating diseases including cyclin-dependent kinase-like 5 (“CDKL5”) deficiency. The Company believes that its platform technologies and its product pipeline uniquely position it at the forefront of advanced therapies to treat a range of devastating rare and orphan diseases. On July 12, 2017, the Company entered into an underwriting agreement (“the Underwriting Agreement”) with J.P. Morgan Securities LLC and Goldman Sachs & Co. LLC, as representatives of the several underwriters set forth on Schedule 1 thereto, relating to an underwritten public offering of the Company’s common stock (the “Offering”). Under the terms of the Underwriting Agreement, the Company issued and sold 21,122,449 shares at a price to the public of $12.25 per share, resulting in gross proceeds of $258.8 million, before deducting underwriting discounts and commissions and offering expenses payable by the Company. The Offering closed on July 18, 2017 and the Company received net proceeds from the Offering, after deducting underwriting discounts and commissions and offering expenses payable by the Company of $243.0 million. See “—Note 8. Equity” for more details. 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 2019.

Summary of Significant Accounting Policies	9 Months Ended
Summary of Significant Accounting Policies	Sep. 30, 2017
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	Note 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 Regulation S-X. Accordingly, they do not include all of the information and disclosures required by U.S. GAAP 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, as amended, for the year ended December 31, 2016. For a complete description of the Company’s accounting policies, please refer to the Annual Report on Form 10-K, as amended for the year ended December 31, 2016. Consolidation The consolidated financial statements include the accounts of the Company and its subsidiaries. Intercompany accounts and transactions have been eliminated in consolidation. Foreign Currency Transactions The functional currency for most of the Company’s foreign subsidiaries is their local currency. For non-U.S. subsidiaries that transact in a functional currency other than the U.S. dollar, assets and liabilities are translated at current rates of exchange at the balance sheet date. Income and expense items are translated at the average foreign exchange rates for the period. Adjustments resulting from the translation of the financial statements of the Company’s foreign operations into U.S. dollars are excluded from the determination of net income and are recorded in accumulated other comprehensive income, a separate component of stockholders’ equity. The Company transacts business in various foreign countries and therefore, is subject to risk of foreign currency exchange rate fluctuations. As such, in June 2016, the Company entered into a forward contract to economically hedge transactional exposure associated with commitments arising from trade accounts payable denominated in a currency other than the functional currency of the respective operating entity. The Company does not designate this forward contract as a hedging instrument under applicable accounting guidance and, therefore, changes in fair value are recorded as other expense in the Consolidated Statements of Operations. The forward contract expired in June 2017. 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. 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. The Company is subject to credit risk from its accounts receivable related to its product sales of Galafold™. The majority of the Company’s accounts receivable at September 30, 2017 have arisen from product sales in the EU. The Company will periodically assess the financial strength of its customers to establish allowances for anticipated losses, if any. For accounts receivable that have arisen from named patient sales, the payment terms are predetermined and the Company evaluates the creditworthiness of each customer on a regular basis. To date, the Company has not incurred any credit losses. Significant Accounting Policies There have been no material changes to the Company’s significant accounting policies during the nine months ended September 30, 2017, 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, as amended, for the year ended December 31, 2016. 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 persuasive evidence of an arrangement exists, title to product and associated risk of loss has passed to the customer, which is typically upon receipt by the end customer, the price is fixed or determinable, collection of the amounts due are reasonably assured and the Company has no further performance obligations. The Company’s net product sales consist solely of sales of Galafold™ for the treatment of Fabry disease in the EU. The Company has recorded revenue on sales where Galafold™ is available either on a commercial basis or through a reimbursed early access program. Orders for Galafold™ are generally received from pharmacies and the ultimate payor is typically a government authority. The Company records revenue net of estimated third party discounts and rebates. Allowances are recorded as a reduction of revenue at the time revenues from product sales are recognized. These allowances are adjusted to reflect known changes in factors and may impact such allowances in the quarter those changes are known. Allowances as of September 30, 2017 are immaterial. Inventories and Cost of Goods Sold Prior to regulatory approval of Galafold™, the Company expensed all manufacturing costs related to Galafold™ as research and development expense. Upon regulatory approval, the Company began capitalizing costs related to the purchase and manufacture of Galafold™. Inventories are stated at the lower of cost and net realizable value, determined by the first-in, first-out method. Inventories are reviewed periodically to identify slow-moving or obsolete inventory based on projected sales activity as well as product shelf-life. In evaluating the recoverability of inventories produced, the probability that revenue will be obtained from the future sale of the related inventory is considered and inventory value is written down for inventory quantities in excess of expected requirements. Expired inventory is disposed of and the related costs are recognized as cost of product sales in the consolidated statements of operations. Cost of goods sold includes the cost of inventory sold, manufacturing and supply chain costs, product shipping and handling costs, provisions for excess and obsolete inventory, as well as royalties payable. A portion of the inventory available for sale was expensed as research and development costs prior to regulatory approval and as such the cost of goods sold and related gross margins are not necessarily indicative of future cost of goods sold and gross margin. 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. Contingent Liabilities On an ongoing basis, the Company may be involved in various claims, and legal proceedings. On a quarterly basis, the Company reviews the status of each significant matter and assesses its potential financial exposure. If the potential loss from any claim, asserted or unasserted, or legal proceeding is considered probable and the amount can be reasonably estimated, the Company will accrue a liability for the estimated loss. Because of uncertainties related to claims and litigation, accruals will be based on the Company’s best estimates based on available information. On a periodic basis, as additional information becomes available, or based on specific events such as the outcome of litigation or settlement of claims, the Company may reassess the potential liability related to these matters and may revise these estimates, which could result in material adverse adjustments to the Company’s operating results. Recent Accounting Pronouncements In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities. The amendments in this Update better align an entity’s risk management activities and financial reporting for hedging relationships through changes to both the designation and measurement guidance for qualifying hedging relationships and the presentation of hedge results. To meet that objective, the amendments expand and refine hedge accounting for both nonfinancial and financial risk components and align the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements. The amendments in this Update also make certain targeted improvements to simplify the application of hedge accounting guidance and ease the administrative burden of hedge documentation requirements and assessing hedge effectiveness. For public business entities, the amendment is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption, including adoption in an interim period, is permitted. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In July 2017, the FASB issued ASU 2017-11, Earnings Per Share (Topic 260); Distinguishing Liabilities from Equity (Topic 480); Derivatives and Hedging (Topic 815): (Part I) Accounting for Certain Financial Instruments with Down Round Features, (Part II) Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception. Part I of this Update addresses the complexity of accounting for certain financial instruments with down round features. Down round features are features of certain equity-linked instruments (or embedded features) that result in the strike price being reduced on the basis of the pricing of future equity offerings. When determining whether certain financial instruments should be classified as liabilities or equity instruments, a down round feature no longer precludes equity classification when assessing whether the instrument is indexed to an entity’s own stock. Part II of this Update addresses the difficulty of navigating Topic 480, Distinguishing Liabilities from Equity, because of the existence of extensive pending content in the FASB Accounting Standards Codification®. For public business entities, the amendments in Part I of this Update are effective for fiscal years, and years, beginning after December 15, 2018. Early adoption is permitted for all entities, including adoption in an interim period. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In May 2017, the FASB issued ASU 2017-09, Compensation—Stock Compensation (Topic 718): Scope of Modification Accounting. The amendments provide guidance on determining which changes to the terms and conditions of share-based payment awards require an entity to apply modification accounting under Topic 718 Compensation—Stock Compensation. An entity should account for the effects of a modification unless all the following are met: 1. The fair value (or calculated value or intrinsic value, if such an alternative measurement method is used) of the modified award is the same as the fair value (or calculated value or intrinsic value, if such an alternative measurement method is used) of the original award immediately before the original award is modified. If the modification does not affect any of the inputs to the valuation technique that the entity uses to value the award, the entity is not required to estimate the value immediately before and after the modification. 2. The vesting conditions of the modified award are the same as the vesting conditions of the original award immediately before the original award is modified. 3. The classification of the modified award as an equity instrument or a liability instrument is the same as the classification of the original award immediately before the original award is modified. The ASU is effective for all entities for annual periods, including interim periods within those annual periods, beginning after December 15, 2017. Early adoption is permitted, including adoption in any interim period. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In March 2017, the FASB issued ASU 2017-08, Receivables—Nonrefundable Fees and Other Costs (Subtopic 310-20), Premium Amortization on Purchased Callable Debt Securities. The amendments shorten the amortization period for certain callable debt securities held at a premium. Specifically, the amendments require the premium to be amortized to the earliest call date. The amendments do not require an accounting change for securities held at a discount; the discount continues to be amortized to maturity. The ASU is effective for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. For other entities, the amendments are effective for fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020. Early adoption is permitted, including adoption in an interim period. If an entity early adopts in an interim period, any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. The amendments should be applied on a modified retrospective basis, with a cumulative-effect adjustment directly to retained earnings as of the beginning of the period of adoption. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment. To simplify the subsequent measurement of goodwill, ASU 2017-04 eliminates Step 2 from the goodwill impairment test. The annual, or interim, goodwill impairment test is performed by comparing the fair value of a reporting unit with its carrying amount. An impairment charge should be recognized for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. In addition, income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit should be considered when measuring the goodwill impairment loss, if applicable. ASU 2017-04 also eliminates the requirements for any reporting unit with a zero or negative carrying amount to perform a qualitative assessment and, if it fails that qualitative test, to perform Step 2 of the goodwill impairment test. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. ASU 2017-04 should be applied on a prospective basis. The nature of and reason for the change in accounting principle should be disclosed upon transition. A public business entity that is a U.S. SEC filer should adopt ASU 2017-04 for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In January 2017, the FASB issued ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business. This Accounting Standards Update clarifies the definition of a business. The amendments affect all companies and other reporting organizations that must determine whether they have acquired or sold a business. The amendments in this update are effective for public companies for annual periods beginning after December 15, 2017, including interim periods within those periods. Early adoption is permitted under certain circumstances. The amendments should be applied prospectively as of the beginning of the period of adoption. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In October 2016, the FASB issued ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory. This Accounting Standards Update requires an entity to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. The amendments eliminate the exception for an intra-entity transfer of an asset other than inventory. The amendments in this Update are effective for public business entities for annual periods beginning after December 15, 2017, including interim reporting periods within those annual reporting periods. Early adoption is permitted for all entities in the first interim period if an entity issues interim financial statements. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. The Company has not completed review of the impact of this guidance and does not expect this new guidance to have a material impact on its consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. The amendments are intended to improve the accounting for employee share-based payments and affect all organizations that issue share-based payment awards to their employees. Several aspects of the accounting for share-based payment award transactions are simplified, including: (a) income tax consequences; (b) classification of awards as either equity or liabilities; and (c) classification on the statement of cash flows. For public companies, the amendments are effective for annual periods beginning after December 15, 2016, and interim periods within those annual periods. The Company adopted ASU 2016-09 on January 1, 2017. Due to the Company’s history of operating losses, the adoption did not result in changes to the Company’s Net loss or Retained earnings and the classification of excess tax benefits on the statement of cash flows for prior periods have not been adjusted. In connection with the adoption of ASU 2016-9, the Company made a policy election to continue its methodology for the development and application of its forfeiture rate. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). This update requires the recognition of lease assets and lease liabilities on the balance sheet for all lease obligations and disclosing key information about leasing arrangements. This update requires the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous generally accepted accounting principles. This update will be effective for the Company for all annual and interim periods beginning after December 15, 2018, including interim periods within those fiscal years. Early application is permitted for all public business entities and all nonpublic business entities upon issuance. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In May 2014, FASB issued ASU 2014-09, Revenue from Contracts with Customers which along with amendments issued in 2015 and 2016, will replace substantially all current US GAAP guidance on this topic and eliminate industry-specific guidance. ASU 2014-09 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 obtain or fulfill a contract. The guidance permits two methods of adoption: full retrospective method (retrospective application to each prior reporting period presented) or modified retrospective method (retrospective application with the cumulative effect of initially applying the guidance recognized at the date of initial application and providing certain additional disclosures). The Company has elected to adopt the new standard using the modified retrospective approach. ASU 2014-09 will become effective for the Company during the first quarter of 2018. The Company continues to assess the impact of ASU 2014-09 on its business and financial statements and expects the adoption of ASU 2014-09 to have an impact to its financial reporting disclosures and internal controls over financial reporting (“ICFR”). The Company has developed implementation controls that allow the Company to properly and timely adopt the new revenue accounting standard on its effective date. The Company will make continuous updates to the quarterly and year-end disclosures, with a focus on both status and internal controls over financial reporting. The Company’s implementation plan includes a phased project plan, an understanding of the new standard and its requirements, assessment of the Company’s revenue streams and specific contracts in the streams. Additionally, the Company continues to monitor modifications, clarifications and interpretations issued by the FASB that may impact its assessment. Upon completion of the Company’s implementation plan and evaluation of the remaining revenue contracts, the Company plans to adopt additional internal controls over financial reporting for any new revenue arrangements. The Company is performing a detailed review of representative contracts and assessing the potential impacts the standard may have on previously reported revenues and future revenues. The Company is also evaluating the potential impact of costs related to obtaining and fulfilling the contracts. The Company is completing its analysis and is on target to complete its assessment of ASU 2014-09 and the impact on the Company’s consolidated financial statements and related disclosures as of January 1, 2018.

Acquisitions	9 Months Ended
Acquisitions	Sep. 30, 2017
Acquisitions
Acquisitions	Note 3. Acquisitions Asset Acquisition of MiaMed, Inc. In July 2016, the Company entered into an Agreement and Plan of Merger (the “MiaMed Agreement”) with MiaMed, Inc., (“MiaMed”). MiaMed is a pre-clinical biotechnology company focused on developing protein replacement therapy for CDKL5 and related diseases. Under the terms of the MiaMed Agreement, the former holders of MiaMed’s capital stock received an aggregate of $6.5 million, comprised of (i) approximately $1.8 million in cash (plus MiaMed’s cash and cash equivalents at closing and less any of MiaMed’s unpaid third-party fees and expenses related to the transaction), and (ii) 825,603 shares of the Company’s common stock, par value $0.01 per share (“Common Stock”). In addition, the Company also agreed to pay up to an additional $83.0 million in connection with the achievement of certain clinical, regulatory and commercial milestones, for a potential aggregate deal value of $89.5 million. The Company evaluated the transaction based on the guidance of Accounting Standard Codification (“ASC”) 805, Business Combinations and concluded that it only acquired inputs and did not acquire any processes. The Company will need to develop its own processes in order to produce an output. Therefore, the Company accounted for the transaction as an asset acquisition and accordingly $6.5 million was expensed to research and development. Acquisition of Scioderm, Inc. In September 2015, the Company acquired Scioderm Inc., (“Scioderm”), a privately-held biopharmaceutical company focused on developing innovative therapies for treating the rare disease EB. The acquisition potentially leveraged the Scioderm development team’s EB expertise with the Company’s global clinical infrastructure to advance SD-101 toward regulatory approvals and the Company’s commercial, patient advocacy, and medical affairs infrastructure to support a successful global launch. The acquisition of Scioderm was accounted for as a purchase of a business in accordance with ASC 805 Business Combinations. On September 13, 2017, the Company reported that top-line data from the randomized, double-blind, placebo-controlled Phase 3 clinical study (ESSENCE, SD-005) to assess the efficacy and safety of the novel topical wound-healing agent SD-101 did not meet the primary endpoints or secondary endpoints in participants with EB. Based on these top-line data, the Company has no current plans to invest in any additional clinical studies or commercial preparation activities for SD-101. For additional information, see “— Note 1. Description of Business.” The associated impairment of Scioderm IPR&D is discussed in “— Note 4. Goodwill and Intangible Assets.” Acquisition of Callidus Biopharma, Inc. In November 2013, the Company acquired Callidus Biopharma, Inc. (“Callidus”), a privately-held biologics company focused on developing best-in-class ERTs for lysosomal storage disorders (“LSDs”) with its lead ERT ATB200 for Pompe disease in late preclinical development. The acquisition of the Callidus assets and technology complements Amicus’ CHART™ platform for the development of next-generation ERTs. For additional information, see “— Note 4. Goodwill and 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1497-128463

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1490-128463

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1486-128463

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1524-128463

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7000-128479

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4922-128472

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4934-128472

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4926-128472

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 4A
-URI http://asc.fasb.org/extlink&oid=73530397&loc=SL65897772-128472

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1383-128463

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6996-128479

+ Details

Goodwill and IPR&D

9 Months Ended

Sep. 30, 2017

Goodwill and IPR&D

Goodwill and IPR&D

Note 4. Goodwill and IPR&D

In connection with the acquisitions, the Company recognized IPR&D of $486.7 million and goodwill of $197.8 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 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.

Goodwill and intangible assets are 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. As discussed in “— Note 1. Description of Business”, in September 2017, the Company reported that top-line data from the randomized, double-blind, placebo-controlled Phase 3 clinical study (ESSENCE, SD-005) to assess the efficacy and safety of the novel topical wound-healing agent SD-101 did not meet the primary endpoints or secondary endpoints in participants with EB. This event led to an assessment to determine if an impairment had occurred for goodwill and IPR&D. Based on tests for impairment, the Company determined that IPR&D had been impaired, however goodwill was not impaired based on qualitative and market capitalization tests performed.

The following table represents the changes in IPR&D for the nine months ended September 30, 2017:

	(in millions)
Balance at December 31, 2016	$	486.7
Impairment in IPR&D related to Scioderm	(463.7		)

Balance September 30, 2017	$	23.0

The following table represents the changes in Goodwill for the nine months ended September 30, 2017:

	(in millions)
Balance at December 31, 2016	$	197.8
Change in goodwill	—

Balance at September 30, 2017	$	197.8

- Definition

The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss.

+ References + Details

Cash, Money Market Funds and Marketable Securities

9 Months Ended

Sep. 30, 2017

Cash, Money Market Funds and Marketable Securities

Cash, Money Market Funds and Marketable Securities

Note 5. Cash, Money Market Funds and Marketable Securities

As of September 30, 2017, the Company held $64.1 million in cash and cash equivalents and $362.5 million of available-for-sale securities which are reported at fair value on the Company’s Consolidated Balance Sheets. 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.

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 greater than 3 months but less than 1 year are classified as short-term, while investments that have maturities greater than 1 year are classified as long-term.

For the nine months ended September 30, 2017, the Company recognized a loss of $0.2 million, related to derivative instruments not designated as hedging instruments in other expense in the Consolidated Statements of Operations. As the forward contract expired in June 2017, there was no liability in the Consolidated Balance Sheets as of September 30, 2017.

Cash and available-for-sale securities are all current unless mentioned otherwise and consisted of the following as of September 30, 2017 and December 31, 2016 (in thousands):

	As of September 30, 2017
	Cost		Gross unrealized Gain		Gross unrealized Loss			Fair Value
Cash balances	$	64,133	$	—	$	—		$	64,133
Corporate debt securities, current portion	192,851		5		(75		)	192,781
Corporate debt securities, non-current portion	15,121		—		(12		)	15,109
Commercial paper	123,880		11		(10		)	123,881
Asset backed securities	30,346		—		(20		)	30,326
Money market	350		—		—			350
Certificate of deposit	50		—		—			50

	$	426,731	$	16	$	(117	)	$	426,630

Included in cash and cash equivalents	$	64,133	$	—	$	—		$	64,133
Included in marketable securities	362,598		16		(117		)	362,497

Total cash and marketable securities	$	426,731	16		$	(117	)	$	426,630

	As of December 31, 2016
	Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash balances	$	187,026	$	—	$	—		$	187,026
Corporate debt securities, current portion	74,564		2		(31		)	74,535
Commercial paper	68,258		132		—			68,390
Money market	350		—		—			350
Certificate of deposit	50		—		—			50

	$	330,248	$	134	$	(31	)	$	330,351

Included in cash and cash equivalents	$	187,026	$	—	$	—		$	187,026
Included in marketable securities	143,222		134		(31		)	143,325

Total cash and marketable securities	$	330,248	134		$	(31	)	$	330,351

For the nine months ended September 30, 2017 and the year ended December 31, 2016, 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 September 30, 2017 and December 31, 2016 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 $241.5 million and $58.7 million as of September 30, 2017 and December 31, 2016, 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.

Debt Instruments

9 Months Ended

Sep. 30, 2017

Debt Instruments

Debt Instruments

Note 7. Debt Instruments

2016 Convertible Debt

On December 21, 2016, the Company issued at par value $250 million aggregate principal amount of unsecured Convertible Senior Notes due 2023 (the “Convertible Notes”), which included the exercise in full of the $25 million over-allotment option granted to the initial purchasers of the Notes, in a private offering to qualified institutional buyers pursuant to Rule 144A under the Securities Act (the “Note Offering”). Interest is payable semiannually on June 15 and December 15 of each year, beginning on June 15, 2017. The Notes will mature on December 15, 2023, unless earlier repurchased, redeemed, or converted in accordance with their terms. The Notes are convertible at the option of the holders, under certain circumstances and during certain periods, into cash, shares of the Company’s Common Stock or a combination thereof and may be settled as described below. The net proceeds from the Note Offering were $243.0 million, after deducting fees and estimated expenses payable by the Company. In addition, the Company used approximately $13.5 million of the net proceeds from the issuance of the Convertible Notes to pay the cost of the capped call transactions (“Capped Call Confirmations”) that the Company entered into in connection with the issuance of the Convertible Notes.

The Convertible Notes are governed by an indenture dated December 21, 2016 (the “Indenture”) by and between the Company and Wilmington Trust, National Association, as trustee.

The Convertible Notes are initially convertible into approximately 40,849,675 shares of the Company’s Common Stock under certain circumstances prior to maturity at a conversion rate of 163.3987 shares per $1,000 principal amount of Convertible Notes, which represents a conversion price of approximately $6.12 per share of Common Stock, subject to adjustment under certain conditions. Holders may convert their Convertible Notes at their option at specified times prior to the maturity date of December 15, 2023, only if:

during any fiscal quarter commencing after March 31, 2017, the last reported sale price of the Company’s Common Stock for at least 20 trading days in the period of 30 consecutive trading days ending on the last trading day of the immediately preceding fiscal quarter is equal to or more than 130% of the conversion price of the Convertible Notes on the last day of such preceding fiscal quarter;

a Holder submits its Convertible Notes for conversion during the five business day period following any five consecutive trading day period in which the trading price for the Convertible Notes, per $1,000 principal amount of the Convertible Notes, for each such trading day was less than 98% of the product of the last reported sale price of the Company’s Common Stock and the conversion rate of the Convertible Notes on such date;

the Company issues to all or substantially all of the holders of Common Stock rights options or warrants entitling them for a period of not more than 60 calendar days after the date of such issuance to subscribe for or purchase shares of the Common Stock, at a price per share less than the average of the Last Reported Sale Prices of the Common Stock for the 10 consecutive Trading Day period ending on, and including, the Trading Day immediately preceding the date of announcement of such issuance or distributes to all or substantially all holders of the Common Stock the Company’s assets, debt securities or rights to purchase the Company’s securities which distribution has a per share value of exceeding 10% of the Last Reported Sale Price of the Common Stock on the Trading Day immediately preceding the date of announcement of such distribution

the Company enters into specified corporate transactions; or

the Company has had a call for redemption, the holder can convert up until the second trading day immediately preceding the redemption date

The Convertible Notes will be convertible, at the option of the note holders, regardless of whether any of the foregoing conditions have been satisfied, on or after September 15, 2023 at any time prior to the close of business on the second scheduled trading day immediately preceding the stated maturity date of December 15, 2023.

The last reported sale price of the Company’s Common Stock was equal to or more than 130% of the conversion price of the Convertible Notes for at least 20 trading days of the 30 consecutive trading days ending on the last day of the second quarter. As a result, the Convertible Notes are currently convertible into the Company’s Common stock as discussed above.

Upon the occurrence of a make-whole fundamental change or if the Company call all or any portion of the Convertible Notes for redemption prior to July 1, 2020, the Company will, in certain circumstances, increase the conversion rate by a number of additional shares for a holder that elects to convert its Convertible Notes in connection with such make-whole fundamental change or during the related redemption period.

Upon conversion, the Company may pay cash, shares of the Company’s Common Stock or a combination of cash and stock, as determined by the Company in its discretion.

The Company accounts for the Convertible Notes as a liability and equity component where the carrying value of the liability component will be valued based on a similar instrument. In accounting for the issuance of the Convertible Notes, the Company separated the Convertible Notes into liability and equity components. The equity component is not re-measured as long as it continues to meet the conditions for equity classification.

In accounting for the issuance of the Convertible Notes, the Company separated the Convertible Notes into liability and equity components based on their relative values. The carrying amount of the liability component was calculated by measuring the fair value of a similar liability that does not have an associated convertible feature. The carrying amount of the equity component, representing the conversion option, was determined by deducting the fair value of the liability component from the par value of the Convertible Notes. The difference between the principal amount of the Convertible Notes and the liability component represents the debt discount, which is recorded as a direct deduction from the related debt liability in the Consolidated Balance Sheets and amortized to interest expense using the effective interest method over the seven-year term of the Convertible Notes. The equity component of the Convertible Notes of approximately $88.3 million is included in additional paid-in capital in the Consolidated Balance Sheets and is not remeasured as long as it continues to meet the conditions for equity classification. Additionally, the Company recorded a deferred tax liability of $29.8 million in relation to the Convertible Notes.

The Company incurred transaction costs of approximately $7.5 million, including approximately $6.9 million that was paid from the gross proceeds of the Convertible Notes offering. In accounting for the transaction costs, the Company allocated the total amount incurred to the liability and equity components using the same proportions as the proceeds from the Convertible Notes. Transaction costs attributable to the liability component were recorded as a direct deduction from the related debt liability in the Consolidated Balance Sheets and amortized to interest expense over the seven-year term of the Convertible Notes. Transaction costs attributable to the equity component were netted with the equity component in additional-paid-in-capital.

The Convertible Notes consist of the following (in thousands): as of September 30, 2017 and December 31, 2016:

Liability component	September 30, 2017			December 31, 2016
Principal	$	250,000		$	250,000
Less: debt discount (1)	(83,972		)	(90,807		)
Less: deferred financing(1)	(4,393		)	(4,729		)

Net carrying value of the debt	$	161,635		$	154,464

(1) Included in the Consolidated Balance Sheets within Convertible Senior Notes (due 2023) and amortized to interest expense over the remaining life of the Convertible Senior Notes using the effective interest rate method.

The fair value of the debt at September 30, 2017 was approximately $644.0 million.

The following table sets forth total interest expense recognized related to the Convertible Notes for the three and nine months ended September 30, 2017:

Components (In thousands)	Three Months ended September 30, 2017		Nine Months ended September 30, 2017
Contractual interest expense	$	1,887	$	5,641
Amortization of debt discount	2,342		6,835
Amortization of deferred financing	122		344

Total	$	4,351	$	12,820

Effective interest rate of the liability component was 10.85%.

The Capped Call Confirmations of $13.5 million are expected generally to reduce the potential dilution to the Common Stock upon any conversion of the Convertible Notes and/or offset the cash payments the Company is required to make in excess of the principal amount upon conversion of the Notes in the event that the market price of the Common Stock is greater than the strike price of the Capped Call Confirmations (which initially corresponds to the initial conversion price of the Convertible Notes and is subject to certain adjustments under the terms of the Capped Call Confirmations), with such reduction and/or offset subject to a cap based on the cap price of the Capped Call Confirmations. The Capped Call Confirmations have an initial cap price of $7.20 per share, which represents a premium of approximately 50% over the closing price of the Company’s Common Stock on the NASDAQ Global Market on December 15, 2016, and is subject to certain adjustments under the terms of the Capped Call Confirmations. The Capped Call Confirmations will cover, subject to anti-dilution adjustments substantially similar to those applicable to the Convertible Notes, the number of shares of Common Stock that will underlie the Convertible Notes. The Capped Call Confirmations do not meet the criteria for separate accounting as a derivative as they are indexed to the Company’s Common Stock. The premiums paid for the Capped Call Confirmations have been included as a net reduction to additional paid-in capital.

Stockholders' Equity

9 Months Ended

Sep. 30, 2017

Stockholders' Equity

Stockholders' Equity

Note 8. Stockholders’ Equity

Common Stock and Warrants

As of September 30, 2017, the Company was authorized to issue 250 million shares of Common Stock. Dividends on Common Stock will be paid when, and if, declared by the board of directors. Each stockholder is entitled to vote on all matters that are appropriate for stockholder voting and is entitled to one vote for each share held.

As discussed in “—Note 1. Business,” in July 2017, the Company entered into the Underwriting Agreement with J.P. Morgan Securities LLC and Goldman Sachs & Co. LLC, as representatives of the several underwriters set forth on Schedule 1 thereto, relating to the Offering. Under the terms of the Underwriting Agreement, the Company issued and sold 21,122,449 shares at a price to the public of $12.25 per share, resulting in gross proceeds of $258.8 million, before deducting underwriting discounts and commissions and offering expenses payable by the Company. The Offering closed on July 18, 2017 and the Company received net proceeds from the Offering, after deducting underwriting discounts and commissions and offering expenses payable by the Company of $243.0 million.

As discussed in “—Note 7. Debt Instruments,” on December 21, 2016, the Company issued $250 million aggregate principal amount of Convertible Notes in a private offering. The Notes will mature on December 15, 2023, unless earlier repurchased, redeemed, or converted in accordance with their terms. The Notes are convertible at the option of the holders, under certain circumstances and during certain periods, into cash, shares of the Company’s Common Stock or a combination thereof. Prior to the close of business on the business day immediately preceding September 15, 2023, the Notes are convertible at the option of the holders of the Notes only under certain conditions. On or after September 15, 2023, until the close of business on the second business day immediately preceding the maturity date, holders of the Notes may convert their Notes at their option at the conversion rate then in effect, irrespective of these conditions. The Company will settle conversions of the Notes by paying or delivering, as the case may be, cash, shares of Common Stock, or a combination of cash and shares of Common Stock, at the Company’s election. The conversion rate will initially be 163.3987 shares of Common Stock per $1,000 principal amount of Notes (equivalent to an initial conversion price of approximately $6.12 per share of Common Stock). The conversion rate is subject to customary adjustments upon the occurrence of certain events.

Equity Incentive Plan

The Company’s Equity Incentive Plans consist of the Amended and Restated 2007 Equity Incentive Plan (the “Plan”) and the 2007 Director Option Plan (the “2007 Director Plan”). The Plan provides 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 Plan is 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 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 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.

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 September 30,						Nine Months Ended September 30,
	2017			2016			2017			2016
Expected stock price volatility	82.5		%	81.6		%	83.1		%	81.3		%
Risk free interest rate	1.8		%	1.2		%	2.0		%	1.5		%
Expected life of options (years)	5.89			6.25			6.21			6.25
Expected annual dividend per share	$	0.00		$	0.00		$	0.00		$	0.00

Beginning in the third quarter of 2017, the average expected life was determined using our actual historical data versus a “simplified” method used in prior quarters. The “simplified” method of estimating the expected exercise term uses the mid-point between the vesting date and the end of the contractual term. In earlier quarters, we did not have sufficient reliable exercise data to justify a change from the use of the “simplified” method of estimating the expected exercise term of employee stock option grants. The impact from this change was not material.

A summary of the Company’s stock options for the nine months ended September 30, 2017 is as follows:

	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value
	(in thousands)					(in millions)
Options outstanding, December 31, 2016	15,497.5		$	7.37
Granted	3,279.5		$	6.37
Exercised	(1,451.2	)	$	6.10
Forfeited	(1,113.8	)	$	9.59

Options outstanding, September 30, 2017	16,212.0		$	7.13	7.2 years	$	129.5

Vested and unvested expected to vest, September 30, 2017	15,338.3		$	7.1	7.1 years	$	122.9
Exercisable at September 30, 2017	8,679.2		$	6.7	6.0 years	$	73.0

As of September 30, 2017, the total unrecognized compensation cost related to non-vested stock options granted was $32.4 million and is expected to be recognized over a weighted average period of three years.

Restricted Stock Units (“RSUs”) and Performance-Based Restricted Stock Units

RSUs awarded under the Plan are generally subject to graded vesting and are contingent on an employee’s continued service. RSUs are generally subject to forfeiture if employment terminates prior to the release of vesting restrictions. The Company expenses the cost of the RSUs, which is determined to be the fair market value of the shares of Common Stock underlying the RSUs at the date of grant, ratably over the period during which the vesting restrictions lapse.

A summary of non-vested RSU activity under the Plan for the nine months ended September 30, 2017 is as follows:

	Number of Share (in thousands)		Weighted Average Grant Date Fair Value		Weighted Average Remaining Years	Aggregate Intrinsic Value (in millions)
Non-vested units as of December 31, 2016	744.4		$	7.86
Granted	2,348.7		$	5.69
Vested	(210.9	)	$	8.57
Forfeited	(191.9	)	$	6.27

Non-vested units as of September 30, 2017	2,690.3		$	6.03	2.68 years	$	40.6

On December 30, 2016, the Compensation Committee approved a form of Performance-Based Restricted Stock Unit Award Agreement (the “Performance-Based RSU Agreement”), to be used for performance-based RSUs granted to participants under the Amended and Restated Amicus Therapeutics, Inc. 2007 Equity Incentive Plan, including named executive officers. Certain awards under the form of Performance-Based RSU Agreement were granted in January 2017. The table above includes 401,413 market performance-based restricted stock units (“MPRSUs”) granted to executives. Vesting of these awards is contingent upon the Company meeting certain total shareholder return (“TSR”) levels as compared to a select peer group over the next three years. The MPRSUs cliff vest at the end of the three-year period and have a maximum potential to vest at 200% (802,826 shares) based on TSR performance. The related share-based compensation expense is determined based on the estimated fair value of the underlying shares on the date of grant and is recognized straight-line over the vesting term. The estimated fair value per share of the MPRSUs was $8.08 and was calculated using a Monte Carlo simulation model. The table above also includes 401,413 performance based awards that will vest over the next three years based on the Company achieving certain clinical milestones.

For the nine months ended September 30, 2017, 210,911 of the RSUs vested and all non-vested units are expected to vest over their normal term. As of September 30, 2017, there was $12.4 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 three 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 September 30,				Nine Months Ended September 30,
	2017		2016		2017		2016
Equity compensation expense recognized in:
Research and development expense	$	2,390	$	2,109	$	7,456	$	6,011
Selling, general and administrative expense	3,110		2,229		9,611		7,076

Total equity compensation expense	$	5,500	$	4,338	$	17,067	$	13,087

- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 4.E)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21484-112644

Reference 3: 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(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644

Reference 5: 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))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 6: 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(31))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

Reference 8: 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(30))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 9: 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 10: 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(d))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656

Reference 13: 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 14: 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 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 16: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644

+ Details

Assets and Liabilities Measured at Fair Value

9 Months Ended

Sep. 30, 2017

Assets and Liabilities Measured at Fair Value

Assets and Liabilities Measured at Fair Value

Note 9. 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.

A summary of the fair value of the Company’s recurring assets and liabilities aggregated by the level in the fair value hierarchy within which those measurements fall as of September 30, 2017 are identified in the following table (in thousands):

	Level 2		Total
Assets:
Commercial paper	$	123,881	$	123,881
Asset-backed securities	30,326		30,326
Corporate debt securities	207,890		207,890
Money market funds	2,464		2,464

	$	364,561	$	364,561

	Level 2		Level 3		Total
Liabilities:
Contingent consideration payable	$	—	$	21,100	$	21,100
Derivative liability	—		—		—
Deferred compensation plan liability	2,134		—		2,134

	$	2,134	$	21,100	$	23,234

A summary of the fair value of the Company’s recurring assets and liabilities aggregated by the level in the fair value hierarchy within which those measurements fall as of December 31, 2016 are identified in the following table (in thousands):

	Level 2		Total
Assets:
Commercial paper	$	68,390	$	68,390
Corporate debt securities	74,535		74,535
Money market funds	1,829		1,829

	$	144,754	$	144,754

	Level 2		Level 3		Total
Liabilities:
Contingent consideration payable	$	—	$	269,722	$	269,722
Derivative liability	265		—		265
Deferred compensation plan liability	1,479		—		1,479

	$	1,744	$	269,722	$	271,466

See “—Note 7. Debt Instruments” for the carrying amount and estimated fair value of the Company’s Convertible Notes due in 2023, that falls into Level 2 category within the fair value level hierarchy. The fair value was determined using broker quotes in a non-active market for valuation.

The Company did not have any Level 3 assets as of September 30, 2017 or as of December 31, 2016.

Cash, Money Market Funds and Marketable Securities

The Company classifies its cash 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 and the money market funds 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 nine months ended September 30, 2017. No transfers of assets between Level 1 and Level 2 of the fair value measurement hierarchy occurred during the nine months ended September 30, 2017.

Contingent Consideration Payable

The contingent consideration payable resulted from the acquisition of Callidus. The 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. The valuation is performed quarterly. Gains and losses are included in the statement of operations.

As discussed in “—Note 3. Acquisitions,” on July 5, 2016, the Company entered into the MiaMed Agreement with MiaMed. MiaMed is a pre-clinical biotechnology company focused on developing protein replacement for CDKL5 and related diseases. Under the terms of the MiaMed Agreement, the Company agreed to pay up to an additional $83.0 million in connection with the achievement of certain clinical, regulatory and commercial milestones, for a potential aggregate deal value of $89.5 million. The MiaMed Agreement was accounted for as an asset acquisition and as such the Company determined that a liability for future milestone payments is not required to be recorded until the actual contingencies are met and will be recorded to research and development expenses when the contingency is resolved.

The contingent consideration payable for Callidus has been classified as a Level 3 recurring 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, including expenses related to CDKL5.

As discussed in “—Note 1. Business,” on September 13, 2017, the Company reported that top-line data from the randomized, double-blind, placebo-controlled Phase 3 clinical study (ESSENCE, SD-005) to assess the efficacy and safety of the novel topical wound-healing agent SD-101 did not meet the primary endpoints or secondary endpoints in participants with EB. Based on these top-line data, the Company has no current plans to invest in any additional clinical studies or commercial preparation activities for SD-101. As such, the contingent consideration related to Scioderm is no longer payable as of September 30, 2017.

On October 4, 2017, the Company announced positive results from the global Phase 1/2 clinical study (ATB200-02) to investigate ATB200/AT2221 in patients with Pompe disease. As a result of these positive results, the probability of success of ATB200 was increased from 32.0%-45.0% at June 30, 2017 to 58.0%-100.0% at September 2017, which drove the increase in fair value of the liability. With these data, the Company plans to continue a series of collaborative discussions with regulators in the US and EU, and expects to provide an update in the first half of 2018. This event was considered in the calculation of the Contingent Consideration as of September 30, 2017.

The following significant unobservable inputs were used in the valuation of the contingent consideration payable of Callidus for the ATB200 Pompe program:

Contingent Consideration Liability	Fair value as of September 30, 2017		Valuation Technique	Unobservable Input	Range

				Discount rate	12.5%

Clinical and regulatory milestones	$	20.7 million	Probability weighted discounted cash flow	Probability of achievement of milestones	58.0%-100.0%

				Projected year of payments	2018-2022

Contingent consideration liabilities are remeasured to fair value each reporting period using discount rates, probabilities of payment and projected payment dates. Projected contingent payment amounts related to clinical and regulatory based milestones are discounted back to the current period using a discounted cash flow model. Increases in discount rates and the time to payment may result in lower fair value measurements. Increases or decreases in any of those inputs together, or in isolation, may result in a significantly lower or higher fair value measurement. There is no assurance that any of the conditions for the milestone payments will be met.

The following table shows the change in the balance of contingent consideration payable for the three and nine months ended September 30, 2017 and 2016, respectively (in thousands):

	Three Months Ended September 30,						Nine Months Ended September 30,
	2017			2016			2017		2016

Balance, beginning of the period	$	265,350		$	276,300		269,722		274,077
Payment of contingent consideration in cash	—			—			(10,000	)	(5,000		)
Payment of contingent consideration in stock	—			—			—		(6,115		)
Changes in fair value during the period, included in Statement of Operations	(244,250		)	(4,110		)	(238,622	)	9,228

Balance, end of the period	$	21,100		$	272,190		21,100		$	272,190

Deferred Compensation Plan- Investment and Liability

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 are classified as trading securities and recorded at fair value with changes in the investments’ fair value recognized in the period they occur. The asset investments consist of market exchanged mutual funds. 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.

Foreign Currency Exchange Rate Exposure

In June 2016, the Company entered into a forward contract to economically hedge transactional exposure associated with commitments arising from trade accounts payable denominated in a currency other than the functional currency of the respective operating entity. The Company did not designate this forward contract as a hedging instrument and carried the liability of $0.3 million as other current liability in the Consolidated Balance Sheet as of December 31, 2016. The forward contract settled in June 2017. Accordingly, there is no liability as of September 30, 2017.

- 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

Basic and Diluted Net Loss per Common Share

9 Months Ended

Sep. 30, 2017

Basic and Diluted Net Loss per Common Share

Basic and Diluted Net Loss per Common Share

Note 10. Basic and Diluted Net Loss per Common Share

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):

	Three Months Ended September 30,						Nine Months Ended September 30,
(In thousands, except per share amounts)	2017			2016			2017			2016
Numerator:
Net loss attributable to common stockholders	$	(111,666	)	$	(46,654	)	$	(214,794	)	$	(141,395	)
Denominator:
Weighted average common shares outstanding — basic and diluted	160,796,841			140,656,109			148,963,864			131,675,690

Dilutive Common Stock equivalents would include the dilutive effect of Common Stock options, convertible debt units, RSUs 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 September 30,
	2017	2016
Options to purchase common stock	16,212	15,773
Convertible debt	40,850	—
Outstanding warrants, convertible to common stock	3,110	3,110
Unvested restricted stock units	2,690	839
Vested restricted stock units, unissued	50	—

Total number of potentially issuable shares	62,912	19,722

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2017
Summary of Significant Accounting Policies
Basis of Presentation	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 Regulation S-X. Accordingly, they do not include all of the information and disclosures required by U.S. GAAP 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, as amended, for the year ended December 31, 2016. For a complete description of the Company’s accounting policies, please refer to the Annual Report on Form 10-K, as amended for the year ended December 31, 2016.
Consolidation	Consolidation The consolidated financial statements include the accounts of the Company and its subsidiaries. Intercompany accounts and transactions have been eliminated in consolidation.
Foreign Currency Transactions	Foreign Currency Transactions The functional currency for most of the Company’s foreign subsidiaries is their local currency. For non-U.S. subsidiaries that transact in a functional currency other than the U.S. dollar, assets and liabilities are translated at current rates of exchange at the balance sheet date. Income and expense items are translated at the average foreign exchange rates for the period. Adjustments resulting from the translation of the financial statements of the Company’s foreign operations into U.S. dollars are excluded from the determination of net income and are recorded in accumulated other comprehensive income, a separate component of stockholders’ equity. The Company transacts business in various foreign countries and therefore, is subject to risk of foreign currency exchange rate fluctuations. As such, in June 2016, the Company entered into a forward contract to economically hedge transactional exposure associated with commitments arising from trade accounts payable denominated in a currency other than the functional currency of the respective operating entity. The Company does not designate this forward contract as a hedging instrument under applicable accounting guidance and, therefore, changes in fair value are recorded as other expense in the Consolidated Statements of Operations. The forward contract expired in June 2017.
Use of Estimates	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.
Concentration of Credit Risk	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. The Company is subject to credit risk from its accounts receivable related to its product sales of Galafold™. The majority of the Company’s accounts receivable at September 30, 2017 have arisen from product sales in the EU. The Company will periodically assess the financial strength of its customers to establish allowances for anticipated losses, if any. For accounts receivable that have arisen from named patient sales, the payment terms are predetermined and the Company evaluates the creditworthiness of each customer on a regular basis. To date, the Company has not incurred any credit losses.
Revenue Recognition	Revenue Recognition The Company recognizes revenue when amounts are realized or realizable and earned. Revenue is considered realizable and earned when persuasive evidence of an arrangement exists, title to product and associated risk of loss has passed to the customer, which is typically upon receipt by the end customer, the price is fixed or determinable, collection of the amounts due are reasonably assured and the Company has no further performance obligations. The Company’s net product sales consist solely of sales of Galafold™ for the treatment of Fabry disease in the EU. The Company has recorded revenue on sales where Galafold™ is available either on a commercial basis or through a reimbursed early access program. Orders for Galafold™ are generally received from pharmacies and the ultimate payor is typically a government authority. The Company records revenue net of estimated third party discounts and rebates. Allowances are recorded as a reduction of revenue at the time revenues from product sales are recognized. These allowances are adjusted to reflect known changes in factors and may impact such allowances in the quarter those changes are known. Allowances as of September 30, 2017 are immaterial.
Inventories and Cost of Goods Sold	Inventories and Cost of Goods Sold Prior to regulatory approval of Galafold™, the Company expensed all manufacturing costs related to Galafold™ as research and development expense. Upon regulatory approval, the Company began capitalizing costs related to the purchase and manufacture of Galafold™. Inventories are stated at the lower of cost and net realizable value, determined by the first-in, first-out method. Inventories are reviewed periodically to identify slow-moving or obsolete inventory based on projected sales activity as well as product shelf-life. In evaluating the recoverability of inventories produced, the probability that revenue will be obtained from the future sale of the related inventory is considered and inventory value is written down for inventory quantities in excess of expected requirements. Expired inventory is disposed of and the related costs are recognized as cost of product sales in the consolidated statements of operations. Cost of goods sold includes the cost of inventory sold, manufacturing and supply chain costs, product shipping and handling costs, provisions for excess and obsolete inventory, as well as royalties payable. A portion of the inventory available for sale was expensed as research and development costs prior to regulatory approval and as such the cost of goods sold and related gross margins are not necessarily indicative of future cost of goods sold and gross margin.
Fair Value Measurements	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.
Contingent Liabilities	Contingent Liabilities On an ongoing basis, the Company may be involved in various claims, and legal proceedings. On a quarterly basis, the Company reviews the status of each significant matter and assesses its potential financial exposure. If the potential loss from any claim, asserted or unasserted, or legal proceeding is considered probable and the amount can be reasonably estimated, the Company will accrue a liability for the estimated loss. Because of uncertainties related to claims and litigation, accruals will be based on the Company’s best estimates based on available information. On a periodic basis, as additional information becomes available, or based on specific events such as the outcome of litigation or settlement of claims, the Company may reassess the potential liability related to these matters and may revise these estimates, which could result in material adverse adjustments to the Company’s operating results.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In August 2017, the FASB issued ASU 2017-12, Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities. The amendments in this Update better align an entity’s risk management activities and financial reporting for hedging relationships through changes to both the designation and measurement guidance for qualifying hedging relationships and the presentation of hedge results. To meet that objective, the amendments expand and refine hedge accounting for both nonfinancial and financial risk components and align the recognition and presentation of the effects of the hedging instrument and the hedged item in the financial statements. The amendments in this Update also make certain targeted improvements to simplify the application of hedge accounting guidance and ease the administrative burden of hedge documentation requirements and assessing hedge effectiveness. For public business entities, the amendment is effective for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption, including adoption in an interim period, is permitted. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In July 2017, the FASB issued ASU 2017-11, Earnings Per Share (Topic 260); Distinguishing Liabilities from Equity (Topic 480); Derivatives and Hedging (Topic 815): (Part I) Accounting for Certain Financial Instruments with Down Round Features, (Part II) Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception. Part I of this Update addresses the complexity of accounting for certain financial instruments with down round features. Down round features are features of certain equity-linked instruments (or embedded features) that result in the strike price being reduced on the basis of the pricing of future equity offerings. When determining whether certain financial instruments should be classified as liabilities or equity instruments, a down round feature no longer precludes equity classification when assessing whether the instrument is indexed to an entity’s own stock. Part II of this Update addresses the difficulty of navigating Topic 480, Distinguishing Liabilities from Equity, because of the existence of extensive pending content in the FASB Accounting Standards Codification®. For public business entities, the amendments in Part I of this Update are effective for fiscal years, and years, beginning after December 15, 2018. Early adoption is permitted for all entities, including adoption in an interim period. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In May 2017, the FASB issued ASU 2017-09, Compensation—Stock Compensation (Topic 718): Scope of Modification Accounting. The amendments provide guidance on determining which changes to the terms and conditions of share-based payment awards require an entity to apply modification accounting under Topic 718 Compensation—Stock Compensation. An entity should account for the effects of a modification unless all the following are met: 1. The fair value (or calculated value or intrinsic value, if such an alternative measurement method is used) of the modified award is the same as the fair value (or calculated value or intrinsic value, if such an alternative measurement method is used) of the original award immediately before the original award is modified. If the modification does not affect any of the inputs to the valuation technique that the entity uses to value the award, the entity is not required to estimate the value immediately before and after the modification. 2. The vesting conditions of the modified award are the same as the vesting conditions of the original award immediately before the original award is modified. 3. The classification of the modified award as an equity instrument or a liability instrument is the same as the classification of the original award immediately before the original award is modified. The ASU is effective for all entities for annual periods, including interim periods within those annual periods, beginning after December 15, 2017. Early adoption is permitted, including adoption in any interim period. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In March 2017, the FASB issued ASU 2017-08, Receivables—Nonrefundable Fees and Other Costs (Subtopic 310-20), Premium Amortization on Purchased Callable Debt Securities. The amendments shorten the amortization period for certain callable debt securities held at a premium. Specifically, the amendments require the premium to be amortized to the earliest call date. The amendments do not require an accounting change for securities held at a discount; the discount continues to be amortized to maturity. The ASU is effective for public business entities for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018. For other entities, the amendments are effective for fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020. Early adoption is permitted, including adoption in an interim period. If an entity early adopts in an interim period, any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. The amendments should be applied on a modified retrospective basis, with a cumulative-effect adjustment directly to retained earnings as of the beginning of the period of adoption. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In January 2017, the FASB issued ASU 2017-04, Intangibles - Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment. To simplify the subsequent measurement of goodwill, ASU 2017-04 eliminates Step 2 from the goodwill impairment test. The annual, or interim, goodwill impairment test is performed by comparing the fair value of a reporting unit with its carrying amount. An impairment charge should be recognized for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. In addition, income tax effects from any tax deductible goodwill on the carrying amount of the reporting unit should be considered when measuring the goodwill impairment loss, if applicable. ASU 2017-04 also eliminates the requirements for any reporting unit with a zero or negative carrying amount to perform a qualitative assessment and, if it fails that qualitative test, to perform Step 2 of the goodwill impairment test. An entity still has the option to perform the qualitative assessment for a reporting unit to determine if the quantitative impairment test is necessary. ASU 2017-04 should be applied on a prospective basis. The nature of and reason for the change in accounting principle should be disclosed upon transition. A public business entity that is a U.S. SEC filer should adopt ASU 2017-04 for its annual or any interim goodwill impairment tests in fiscal years beginning after December 15, 2019. Early adoption is permitted for interim or annual goodwill impairment tests performed on testing dates after January 1, 2017. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In January 2017, the FASB issued ASU 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business. This Accounting Standards Update clarifies the definition of a business. The amendments affect all companies and other reporting organizations that must determine whether they have acquired or sold a business. The amendments in this update are effective for public companies for annual periods beginning after December 15, 2017, including interim periods within those periods. Early adoption is permitted under certain circumstances. The amendments should be applied prospectively as of the beginning of the period of adoption. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In October 2016, the FASB issued ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory. This Accounting Standards Update requires an entity to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs. The amendments eliminate the exception for an intra-entity transfer of an asset other than inventory. The amendments in this Update are effective for public business entities for annual periods beginning after December 15, 2017, including interim reporting periods within those annual reporting periods. Early adoption is permitted for all entities in the first interim period if an entity issues interim financial statements. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. The Company has not completed review of the impact of this guidance and does not expect this new guidance to have a material impact on its consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, Compensation - Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting. The amendments are intended to improve the accounting for employee share-based payments and affect all organizations that issue share-based payment awards to their employees. Several aspects of the accounting for share-based payment award transactions are simplified, including: (a) income tax consequences; (b) classification of awards as either equity or liabilities; and (c) classification on the statement of cash flows. For public companies, the amendments are effective for annual periods beginning after December 15, 2016, and interim periods within those annual periods. The Company adopted ASU 2016-09 on January 1, 2017. Due to the Company’s history of operating losses, the adoption did not result in changes to the Company’s Net loss or Retained earnings and the classification of excess tax benefits on the statement of cash flows for prior periods have not been adjusted. In connection with the adoption of ASU 2016-9, the Company made a policy election to continue its methodology for the development and application of its forfeiture rate. In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842). This update requires the recognition of lease assets and lease liabilities on the balance sheet for all lease obligations and disclosing key information about leasing arrangements. This update requires the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under previous generally accepted accounting principles. This update will be effective for the Company for all annual and interim periods beginning after December 15, 2018, including interim periods within those fiscal years. Early application is permitted for all public business entities and all nonpublic business entities upon issuance. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In May 2014, FASB issued ASU 2014-09, Revenue from Contracts with Customers which along with amendments issued in 2015 and 2016, will replace substantially all current US GAAP guidance on this topic and eliminate industry-specific guidance. ASU 2014-09 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 obtain or fulfill a contract. The guidance permits two methods of adoption: full retrospective method (retrospective application to each prior reporting period presented) or modified retrospective method (retrospective application with the cumulative effect of initially applying the guidance recognized at the date of initial application and providing certain additional disclosures). The Company has elected to adopt the new standard using the modified retrospective approach. ASU 2014-09 will become effective for the Company during the first quarter of 2018. The Company continues to assess the impact of ASU 2014-09 on its business and financial statements and expects the adoption of ASU 2014-09 to have an impact to its financial reporting disclosures and internal controls over financial reporting (“ICFR”). The Company has developed implementation controls that allow the Company to properly and timely adopt the new revenue accounting standard on its effective date. The Company will make continuous updates to the quarterly and year-end disclosures, with a focus on both status and internal controls over financial reporting. The Company’s implementation plan includes a phased project plan, an understanding of the new standard and its requirements, assessment of the Company’s revenue streams and specific contracts in the streams. Additionally, the Company continues to monitor modifications, clarifications and interpretations issued by the FASB that may impact its assessment. Upon completion of the Company’s implementation plan and evaluation of the remaining revenue contracts, the Company plans to adopt additional internal controls over financial reporting for any new revenue arrangements. The Company is performing a detailed review of representative contracts and assessing the potential impacts the standard may have on previously reported revenues and future revenues. The Company is also evaluating the potential impact of costs related to obtaining and fulfilling the contracts. The Company is completing its analysis and is on target to complete its assessment of ASU 2014-09 and the impact on the Company’s consolidated financial statements and related disclosures as of January 1, 2018.

Cash, Money Market Funds and Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2017

Cash, Money Market Funds and Marketable Securities

Schedule of cash and available-for-sale securities

Cash and available-for-sale securities are all current unless mentioned otherwise and consisted of the following as of September 30, 2017 and December 31, 2016 (in thousands):

	As of September 30, 2017
	Cost		Gross unrealized Gain		Gross unrealized Loss			Fair Value
Cash balances	$	64,133	$	—	$	—		$	64,133
Corporate debt securities, current portion	192,851		5		(75		)	192,781
Corporate debt securities, non-current portion	15,121		—		(12		)	15,109
Commercial paper	123,880		11		(10		)	123,881
Asset backed securities	30,346		—		(20		)	30,326
Money market	350		—		—			350
Certificate of deposit	50		—		—			50

	$	426,731	$	16	$	(117	)	$	426,630

Included in cash and cash equivalents	$	64,133	$	—	$	—		$	64,133
Included in marketable securities	362,598		16		(117		)	362,497

Total cash and marketable securities	$	426,731	16		$	(117	)	$	426,630

	As of December 31, 2016
	Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash balances	$	187,026	$	—	$	—		$	187,026
Corporate debt securities, current portion	74,564		2		(31		)	74,535
Commercial paper	68,258		132		—			68,390
Money market	350		—		—			350
Certificate of deposit	50		—		—			50

	$	330,248	$	134	$	(31	)	$	330,351

Included in cash and cash equivalents	$	187,026	$	—	$	—		$	187,026
Included in marketable securities	143,222		134		(31		)	143,325

Total cash and marketable securities	$	330,248	134		$	(31	)	$	330,351

Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2017

Stockholders' Equity

Schedule of fair value weighted-average assumptions

	Three Months Ended September 30,						Nine Months Ended September 30,
	2017			2016			2017			2016
Expected stock price volatility	82.5		%	81.6		%	83.1		%	81.3		%
Risk free interest rate	1.8		%	1.2		%	2.0		%	1.5		%
Expected life of options (years)	5.89			6.25			6.21			6.25
Expected annual dividend per share	$	0.00		$	0.00		$	0.00		$	0.00

Summary of stock options outstanding

	Number of Shares		Weighted Average Exercise Price		Weighted Average Remaining Contractual Life	Aggregate Intrinsic Value
	(in thousands)					(in millions)
Options outstanding, December 31, 2016	15,497.5		$	7.37
Granted	3,279.5		$	6.37
Exercised	(1,451.2	)	$	6.10
Forfeited	(1,113.8	)	$	9.59

Options outstanding, September 30, 2017	16,212.0		$	7.13	7.2 years	$	129.5

Vested and unvested expected to vest, September 30, 2017	15,338.3		$	7.1	7.1 years	$	122.9
Exercisable at September 30, 2017	8,679.2		$	6.7	6.0 years	$	73.0

Summary of non-vested Restricted Stock Units activity

	Number of Share (in thousands)		Weighted Average Grant Date Fair Value		Weighted Average Remaining Years	Aggregate Intrinsic Value (in millions)
Non-vested units as of December 31, 2016	744.4		$	7.86
Granted	2,348.7		$	5.69
Vested	(210.9	)	$	8.57
Forfeited	(191.9	)	$	6.27

Non-vested units as of September 30, 2017	2,690.3		$	6.03	2.68 years	$	40.6

Summary of the equity-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 September 30,				Nine Months Ended September 30,
	2017		2016		2017		2016
Equity compensation expense recognized in:
Research and development expense	$	2,390	$	2,109	$	7,456	$	6,011
Selling, general and administrative expense	3,110		2,229		9,611		7,076

Total equity compensation expense	$	5,500	$	4,338	$	17,067	$	13,087

Assets and Liabilities Measured at Fair Value (Tables)

9 Months Ended

Sep. 30, 2017

Summary of assets and liabilities subject to fair value measurements

	Level 2		Total
Assets:
Commercial paper	$	123,881	$	123,881
Asset-backed securities	30,326		30,326
Corporate debt securities	207,890		207,890
Money market funds	2,464		2,464

	$	364,561	$	364,561

	Level 2		Level 3		Total
Liabilities:
Contingent consideration payable	$	—	$	21,100	$	21,100
Derivative liability	—		—		—
Deferred compensation plan liability	2,134		—		2,134

	$	2,134	$	21,100	$	23,234

	Level 2		Total
Assets:
Commercial paper	$	68,390	$	68,390
Corporate debt securities	74,535		74,535
Money market funds	1,829		1,829

	$	144,754	$	144,754

	Level 2		Level 3		Total
Liabilities:
Contingent consideration payable	$	—	$	269,722	$	269,722
Derivative liability	265		—		265
Deferred compensation plan liability	1,479		—		1,479

	$	1,744	$	269,722	$	271,466

Schedule of changes in contingent consideration payable

The following table shows the change in the balance of contingent consideration payable for the three and nine months ended September 30, 2017 and 2016, respectively (in thousands):

	Three Months Ended September 30,						Nine Months Ended September 30,
	2017			2016			2017		2016

Balance, beginning of the period	$	265,350		$	276,300		269,722		274,077
Payment of contingent consideration in cash	—			—			(10,000	)	(5,000		)
Payment of contingent consideration in stock	—			—			—		(6,115		)
Changes in fair value during the period, included in Statement of Operations	(244,250		)	(4,110		)	(238,622	)	9,228

Balance, end of the period	$	21,100		$	272,190		21,100		$	272,190

Callidus

Schedule of significant unobservable inputs used in the valuation of the contingent consideration payable

Contingent Consideration Liability	Fair value as of September 30, 2017		Valuation Technique	Unobservable Input	Range

				Discount rate	12.5%

Clinical and regulatory milestones	$	20.7 million	Probability weighted discounted cash flow	Probability of achievement of milestones	58.0%-100.0%

				Projected year of payments	2018-2022

- Definition

Tabular disclosure of financial instruments measured at fair value, including those classified in shareholders' equity measured on a recurring or nonrecurring basis. Disclosures include, but are not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Nonrecurring fair value measurements are those that are required or permitted in the statement of financial position in particular circumstances.

+ References + Details

Basic and Diluted Net Loss per Common Share (Tables)

9 Months Ended

Sep. 30, 2017

Basic and Diluted Net Loss per Common Share

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

	Three Months Ended September 30,						Nine Months Ended September 30,
(In thousands, except per share amounts)	2017			2016			2017			2016
Numerator:
Net loss attributable to common stockholders	$	(111,666	)	$	(46,654	)	$	(214,794	)	$	(141,395	)
Denominator:
Weighted average common shares outstanding — basic and diluted	160,796,841			140,656,109			148,963,864			131,675,690

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 September 30,
	2017	2016
Options to purchase common stock	16,212	15,773
Convertible debt	40,850	—
Outstanding warrants, convertible to common stock	3,110	3,110
Unvested restricted stock units	2,690	839
Vested restricted stock units, unissued	50	—

Total number of potentially issuable shares	62,912	19,722

Description of Business (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended		9 Months Ended
	Jul. 18, 2017	Jul. 12, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Corporate Information, Status of Operations and Management Plans
Changes in fair value of contingent consideration payable			$ 244,250	$ 4,110	$ 238,622	$ (9,228)
Contingent consideration payable			21,100		21,100		$ 269,722
Loss on impairment			465,427		465,427
Net proceeds from the issuance of common stock					243,036	$ 97,068
SD-101
Corporate Information, Status of Operations and Management Plans
Loss on impairment related to fixed assets					1,700
Changes in fair value of contingent consideration payable			254,700
Contingent consideration payable			$ 0		0
Selling, general and administrative costs due to wind-down					400
Research and development expenses due to wind-down					8,100
Common Stock
Corporate Information, Status of Operations and Management Plans
Number of common stock issued from underwriting agreement		21,122,449
Price per share of common stock issued (in dollars per share)		$ 12.25
Gross proceeds from issue of common stock before deducting underwriting discounts and commissions		$ 258,800
Net proceeds from the issuance of common stock	$ 243,000				243,000
IPR&D
Corporate Information, Status of Operations and Management Plans
Loss on impairment of intangible assets					463,700
IPR&D \| SD-101
Corporate Information, Status of Operations and Management Plans
Loss on impairment of intangible assets					$ 463,700

Cash, Money Market Funds and Marketable Securities (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
Cash, Money Market Funds, and Marketable Securities
Cash and cash equivalents, Amortized Cost	$ 64,133	$ 187,026	$ 33,115	$ 69,485
Cash and cash equivalents, Fair Value	64,133	187,026
Marketable securities, Amortized Cost	362,598	143,222
Gross Unrealized Gain	16	134
Gross Unrealized Loss	(117)	(31)
Marketable securities, Fair Value	362,497	143,325
Cash and marketable securities, Amortized Cost	426,731	330,248
Cash and marketable securities, Fair Value	426,630	330,351
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	241,500	58,700
Other current liabilities
Cash, Money Market Funds, and Marketable Securities
Derivative liabilities	0	300
Other current liabilities \| Foreign exchange forward contract \| Not designated
Cash, Money Market Funds, and Marketable Securities
Derivative liabilities	0
Other expense \| Foreign exchange forward contract \| Not designated
Cash, Money Market Funds, and Marketable Securities
Gain (loss) on derivative instruments	(200)
Corporate debt securities, current portion
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	192,851	74,564
Gross Unrealized Gain	5	2
Gross Unrealized Loss	(75)	(31)
Marketable securities, Fair Value	192,781	74,535
Corporate debt securities, non-current portion
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	15,121
Gross Unrealized Loss	(12)
Marketable securities, Fair Value	15,109
Commercial paper
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	123,880	68,258
Gross Unrealized Gain	11	132
Gross Unrealized Loss	(10)
Marketable securities, Fair Value	123,881	68,390
Asset-backed securities
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	30,346
Gross Unrealized Loss	(20)
Marketable securities, Fair Value	30,326
Money market
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	350	350
Marketable securities, Fair Value	350	350
Certificate of deposit
Cash, Money Market Funds, and Marketable Securities
Marketable securities, Amortized Cost	50	50
Marketable securities, Fair Value	$ 50	$ 50

Debt Instruments - Convertible Debt (Details)			3 Months Ended	9 Months Ended	12 Months Ended
Debt Instruments - Convertible Debt (Details)	Dec. 21, 2016 USD ($) $ / shares shares	Dec. 15, 2016 $ / item	Sep. 30, 2017 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)
Convertible Debt
Debt instrument term					7 years
Equity component of the Convertible Notes					$ 88,300,000
Deferred tax liability in relation to the Convertible Notes					29,800,000
Convertible Notes \| 2016 Convertible Notes
Convertible Debt
Aggregate principle amount	$ 250,000,000
Net proceeds after deducting fees and estimated expenses	243,000,000
Net proceeds from convertible notes to pay capped call transactions	$ 13,500,000
Shares of common stock issued per increment of note principal \| shares	40,849,675
Debt conversion ratio (in shares)	0.1633987
Increment used for debt conversion	$ 1,000
Conversion price (in dollars per share) \| $ / shares	$ 6.12
Maximum calendar days allowed to holders of common stock rights options or warrants to purchase of common stock	60 days
Trading days for price per share based on last reported sale price	10 days
Minimum percentage of per share value of last reported sale price of common stock	10.00%
Convertible notes issuance costs	$ 7,500,000
Convertible notes issuance cost paid	$ 6,900,000
Liability components of convertible notes
Principal			$ 250,000,000	$ 250,000,000	250,000,000
Less: debt discount			(83,972,000)	(83,972,000)	(90,807,000)
Less: deferred financing			(4,393,000)	(4,393,000)	(4,729,000)
Net carrying value of the debt			161,635,000	161,635,000	$ 154,464,000
Fair value of the debt			644,000,000	644,000,000
Interest expense
Contractual interest expense			1,887,000	5,641,000
Amortization of debt discount			2,342,000	6,835,000
Amortization of deferred financing			122,000	344,000
Total interest expense			$ 4,351,000	$ 12,820,000
Effective interest rate of the liability component			10.85%	10.85%
Initial cap price \| $ / item		7.20
Capped call premium on closing price		50.00%
Convertible Notes \| 2016 Convertible Notes \| Convertible Notes, condition 1
Convertible Debt
Threshold consecutive trading days	30 days
Threshold percentage	130.00%
Convertible Notes \| 2016 Convertible Notes \| Convertible Notes, condition 1 \| Minimum
Convertible Debt
Threshold trading days	20 days
Convertible Notes \| 2016 Convertible Notes \| Convertible Notes, condition 2
Convertible Debt
Increment used for debt conversion	$ 1,000
Threshold trading days	5 days
Threshold consecutive trading days	5 days
Maximum threshold percentage	98.00%
Over-allotment Option \| Private Placement Purchase Agreement \| Convertible Notes \| 2016 Convertible Notes
Convertible Debt
Aggregate principle amount	$ 25,000,000

Stockholders' Equity - Common Stock and Warrants (Details)				9 Months Ended
	Jul. 18, 2017 USD ($)	Jul. 12, 2017 USD ($) $ / shares shares	Dec. 21, 2016 USD ($) $ / shares	Sep. 30, 2017 USD ($) item shares	Sep. 30, 2016 USD ($)	Dec. 31, 2016 shares
Convertible Debt
Authorized number of shares of common stock \| shares				250,000,000		250,000,000
Voting right for each share held, number \| item				1
Net proceeds from the issuance of common stock				$ 243,036,000	$ 97,068,000
Common Stock
Convertible Debt
Number of common stock issued from underwriting agreement \| shares		21,122,449
Price per share of common stock issued (in dollars per share) \| $ / shares		$ 12.25
Gross proceeds from issue of common stock before deducting underwriting discounts and commissions		$ 258,800,000
Net proceeds from the issuance of common stock	$ 243,000,000			$ 243,000,000
2016 Convertible Notes \| Convertible Notes
Convertible Debt
Aggregate principle amount			$ 250,000,000
Debt conversion ratio (in shares)			0.1633987
Increment used for debt conversion			$ 1,000
Conversion price (in dollars per share) \| $ / shares			$ 6.12
2016 Convertible Notes \| Convertible Notes \| Common Stock
Convertible Debt
Debt conversion ratio (in shares)			0.1633987
Increment used for debt conversion			$ 1,000
Conversion price (in dollars per share) \| $ / shares			$ 6.12

Stockholders' Equity - Nonqualified Cash and Equity Incentive Plans (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Common stock options
Fair value weighted-average assumptions:
Expected stock price volatility (as a percent)	82.50%	81.60%	83.10%	81.30%
Risk free interest rate (as a percent)	1.80%	1.20%	2.00%	1.50%
Expected life of options	5 years 10 months 21 days	6 years 3 months	6 years 2 months 16 days	6 years 3 months
Expected annual dividend per share (in dollars per share)	$ 0.00	$ 0.00	$ 0.00	$ 0.00
Number of Shares
Balance at the beginning of the period (in shares)			15,497,500
Options granted (in shares)			3,279,500
Options exercised (in shares)			(1,451,200)
Options forfeited (in shares)			(1,113,800)
Balance at the end of the period (in shares)	16,212,000		16,212,000
Vested and unvested expected to vest as of the end of the period (in shares)	15,338,300		15,338,300
Exercisable at the end of the period (in shares)	8,679,200		8,679,200
Weighted Average Exercise Price
Balance at the beginning of the period (in dollars per share)			$ 7.37
Options granted (in dollars per share)			6.37
Options exercised (in dollars per share)			6.10
Options forfeited (in dollars per share)			9.59
Balance at the end of the period (in dollars per share)	$ 7.13		7.13
Vested and unvested expected to vest as of the end of the period (in dollars per share)	7.10		7.10
Exercisable at the end of the period (in dollars per share)	$ 6.70		$ 6.70
Weighted Average Remaining Contractual Life
Balance at the end of the period			7 years 2 months 12 days
Vested and unvested expected to vest at the end of the period			7 years 1 month 6 days
Exercisable at the end of the period			6 years
Aggregate Intrinsic Value
Aggregate intrinsic value of options outstanding (in dollars)	$ 129,500		$ 129,500
Aggregate intrinsic value of options vested and unvested expected to vest (in dollars)	122,900		122,900
Aggregate intrinsic value of options exercisable (in dollars)	73,000		73,000
Total unrecognized compensation cost related to non-vested stock options granted (in dollars)	$ 32,400,000		$ 32,400,000
Period of recognition unrecognized compensation costs (in years)			3 years
Restricted stock units (RSUs) \| Amended and Restated 2007 Equity Incentive Plan
Aggregate Intrinsic Value
Estimated fair value (in dollars per share)			$ 5.69
Period of recognition unrecognized compensation costs (in years)			3 years
Restricted Stock Units, Number of Shares
Non-vested units as of the beginning of the period (in shares)			744,400
Granted (in shares)			2,348,700
Vested (in shares)			(210,911)
Forfeited (in shares)			(191,900)
Non-vested units as of the end of the period (in shares)	2,690,300		2,690,300
Weighted Average Grant Date Fair Value
Non-vested units as of the beginning of the period (in dollars per share)			$ 7.86
Granted (in dollars per share)			5.69
Vested (in dollars per share)			8.57
Forfeited (in dollars per share)			6.27
Non-vested units as of the end of the period (in dollars per share)	$ 6.03		$ 6.03
Weighted Average Remaining Years
Non-vested units as of the end of the period			2 years 8 months 5 days
Aggregate Intrinsic Value
Non-vested units as of the end of the period (in dollars)	$ 40,600,000		$ 40,600,000
Unrecognized compensation cost related to unvested RSU's (in dollars)	$ 12,400,000		$ 12,400,000
Clinical milestone \| Restricted stock units (RSUs) \| Amended and Restated 2007 Equity Incentive Plan
Aggregate Intrinsic Value
Vesting period			3 years
Restricted Stock Units, Number of Shares
Granted (in shares)			401,413
Executive Officers \| Market Performance-based Restricted Stock Units (MPRSUs) \| Amended and Restated 2007 Equity Incentive Plan
Aggregate Intrinsic Value
Vesting period			3 years
Estimated fair value (in dollars per share)			$ 8.08
Restricted Stock Units, Number of Shares
Granted (in shares)			401,413
Weighted Average Grant Date Fair Value
Granted (in dollars per share)			$ 8.08
Executive Officers \| Market Performance-based Restricted Stock Units (MPRSUs) \| Amended and Restated 2007 Equity Incentive Plan \| Cliff Vesting
Aggregate Intrinsic Value
Vesting period			3 years
Maximum \| Executive Officers \| Market Performance-based Restricted Stock Units (MPRSUs) \| Amended and Restated 2007 Equity Incentive Plan
Fair value weighted-average assumptions:
Vesting percentage			200.00%
Number of Shares
Exercisable at the end of the period (in shares)	802,826		802,826

Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Jul. 05, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Dec. 31, 2016
Financial assets and liabilities subject to fair value measurements
Transfer of assets from Level 1 to Level 2		$ 0		$ 0
Transfer of assets from Level 2 to Level 1		0		0
Assets:
Fair value of assets		364,561		364,561			$ 144,754
Liabilities:
Contingent consideration payable		21,100		21,100			269,722
Derivative liability							265
Deferred compensation plan liability		2,134		2,134			1,479
Fair value of liabilities		23,234		23,234			271,466
Contingent consideration payable
Balance, beginning of the period		265,350	$ 276,300	269,722	$ 274,077
Payment of contingent consideration in cash				(10,000)	(5,000)
Payment of contingent consideration in stock					(6,115)
Changes in fair value during the period, included in Statement of Operations		(244,250)	(4,110)	(238,622)	9,228
Balance, end of the period		21,100	$ 272,190	21,100	$ 272,190
Other current liabilities
Foreign Currency Exchange Rate Exposure
Derivative liabilities		0		0			300
MiaMed Inc
Contingent consideration payable
Asset acquisition, potential aggregate deal value	$ 89,500
Maximum \| Clinical and Regulatory Approval milestones \| MiaMed Inc
Contingent consideration payable
Contingent consideration payable upon achievement of milestones	83,000
Maximum \| Clinical, Regulatory and Commercial milestones \| MiaMed Inc
Contingent consideration payable
Contingent consideration payable upon achievement of milestones	$ 83,000
ATB200 Pompe program \| Clinical and Regulatory Approval milestones \| Callidus
Liabilities:
Contingent consideration payable		20,700		20,700
Commercial paper
Assets:
Fair value of assets		123,881		123,881			68,390
Asset-backed securities
Assets:
Fair value of assets		30,326		30,326
Corporate debt securities
Assets:
Fair value of assets		207,890		207,890			74,535
Money market
Assets:
Fair value of assets		2,464		2,464			1,829
Level 2
Assets:
Fair value of assets		364,561		364,561			144,754
Liabilities:
Derivative liability							265
Deferred compensation plan liability		2,134		2,134			1,479
Fair value of liabilities		2,134		2,134			1,744
Level 2 \| Commercial paper
Assets:
Fair value of assets		123,881		123,881			68,390
Level 2 \| Asset-backed securities
Assets:
Fair value of assets		30,326		30,326
Level 2 \| Corporate debt securities
Assets:
Fair value of assets		207,890		207,890			74,535
Level 2 \| Money market
Assets:
Fair value of assets		2,464		2,464			1,829
Level 3
Liabilities:
Contingent consideration payable		21,100		21,100			269,722
Fair value of liabilities		$ 21,100		$ 21,100			$ 269,722
Level 3 \| ATB200 Pompe program \| Clinical and Regulatory Approval milestones \| Probability weighted discounted cash flow \| Callidus
Liabilities:
Discount rate (as a percent)				12.50%
Level 3 \| ATB200 Pompe program \| Minimum \| Clinical and Regulatory Approval milestones \| Probability weighted discounted cash flow \| Callidus
Liabilities:
Probability of achievement of milestones (as a percent)		58.00%		58.00%		32.00%
Level 3 \| ATB200 Pompe program \| Maximum \| Clinical and Regulatory Approval milestones \| Probability weighted discounted cash flow \| Callidus
Liabilities:
Probability of achievement of milestones (as a percent)		100.00%		100.00%		45.00%

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Consolidated Balance Sheets
Accumulated depreciation of property and equipment (in dollars)	$ 13,273	$ 12,495
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	250,000,000	250,000,000
Common stock, shares issued	165,491,141	142,691,986
Common stock, shares outstanding	165,491,141	142,691,986

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Consolidated Statements of Comprehensive Loss
Net loss	$ (111,666)	$ (46,654)	$ (214,794)	$ (141,395)
Other comprehensive (loss)/ gain:
Foreign currency translation adjustment (loss)/ gain	(1,176)	220	(3,312)	1,062
Unrealized (loss)/ gain on available-for-sale securities	(131)	86	(203)	402
Other comprehensive (loss)/income	(1,307)	306	(3,515)	1,464
Comprehensive loss	$ (112,973)	$ (46,348)	$ (218,309)	$ (139,931)

Commitments and Contingencies	9 Months Ended
Commitments and Contingencies	Sep. 30, 2017
Commitments and Contingencies
Commitments and Contingencies	Note 11. Commitments and Contingencies Since October 1, 2015, three purported securities class action lawsuits have been commenced in the United States District Court for New Jersey, naming as defendants the Company, its Chairman and Chief Executive Officer, and in one of the actions, its Chief Medical Officer. The lawsuits allege violations of the Securities Exchange Act of 1934 in connection with allegedly false and misleading statements made by the Company related to the regulatory approval path for migalastat. The plaintiffs seek, among other things, damages for purchasers of the Company’s Common Stock during different periods, all of which fall between March 19, 2015 and October 1, 2015. It is possible that additional suits will be filed, or allegations received from stockholders, with respect to similar matters and also naming the Company and/or its officers and directors as defendants. On May 26, 2016, the Court consolidated these lawsuits into a single action and appointed a lead plaintiff. The lead plaintiff filed a Consolidated Amended Class Action Complaint on July 11, 2016. On August 25, 2016, the defendants filed a motion to dismiss in response to the Consolidated Amended Class Action Complaint. This motion to dismiss was fully briefed on October 28, 2016 but has not been decided. Lead plaintiff and defendants have reached an agreement in principal to fully and finally settle all claims asserted in the Consolidated Amended Class Action Complaint. On June 29, 2017, the Court granted preliminary approval to the settlement. In connection with the Court’s preliminary approval, the settlement amount was paid into the plaintiff’s fund. The settlement is immaterial to the Company’s consolidated financial statements and is subject to final court approval. A fairness hearing to determine whether the settlement will be approved is now scheduled to occur on November 9, 2017. The settlement amount was covered under insurance. On or about March 3, 2016, a derivative lawsuit was filed by an Amicus shareholder purportedly on Amicus’ behalf in the Superior Court of New Jersey, Middlesex County, Chancery Division, against various officers and directors of the Company. Amicus itself is named as a nominal defendant. The derivative lawsuit alleges similar facts and circumstances as the three purported securities class action lawsuits described above and further alleges claims for breach of state law fiduciary duties, waste of corporate assets, unjust enrichment, abuse of control, and gross mismanagement based on allegedly false and misleading statements made by Amicus related to the regulatory approval path for migalastat HCl. The plaintiff seeks, among other things, to require the Amicus Board to take certain actions to reform its corporate governance procedures, including greater shareholder input and a provision to permit shareholders to nominate candidates for election to the Board, along with restitution, costs of suit and attorney’s fees. On February 7, 2017, the complaint was dismissed by the Court without prejudice. These lawsuits and any other related lawsuits are subject to inherent uncertainties and the actual cost will depend upon many unknown factors. The outcome of the litigation is necessarily uncertain and we could be forced to expend significant resources in the defense of these suits, and we may not prevail.

Subsequent Events	9 Months Ended
Subsequent Events	Sep. 30, 2017
Subsequent Events
Subsequent Events	Note 12. Subsequent Events On October 4, 2017 the Company announced positive results from the global Phase 1/2 clinical study (ATB200-02) to investigate ATB200/AT2221 in patients with Pompe disease. These clinical results were featured at the 22nd International Congress of the World Muscle Society in a late-breaker poster. With these data, the Company plans to continue a series of collaborative discussions with regulators in the US and EU, and expects to provide an update in the first half of 2018. This event was considered into the calculation of the Contingent Consideration as of September 30, 2017, as discussed in “—Note 9. Assets and Liabilities at Fair Value.”

Summary of Significant Accounting Policies - Foreign Currency Transactions (Details)	1 Months Ended
	Jun. 30, 2016 item
Summary of Significant Accounting Policies
Number of forward contracts	1

Goodwill and IPR&D - IPR&D (Details) - IPR&D $ in Millions	9 Months Ended
Goodwill and IPR&D - IPR&D (Details) - IPR&D $ in Millions	Sep. 30, 2017 USD ($)
Changes in IPR&D
Balance at beginning of the period	$ 486.7
Impairment in IPR&D related to Scioderm	(463.7)
Balance at end of the period	23.0
Business Acquisitions
Changes in IPR&D
Balance at end of the period	$ 486.7

Goodwill and IPR&D - Goodwill (Details) $ in Thousands	9 Months Ended
Goodwill and IPR&D - Goodwill (Details) $ in Thousands	Sep. 30, 2017 USD ($)
Changes in goodwill
Balance at beginning of the period	$ 197,797
Balance at end of the period	197,797
Goodwill
Changes in goodwill
Balance at beginning of the period	197,800
Change in goodwill	0
Balance at end of the period	197,800
Business Acquisitions \| Goodwill
Changes in goodwill
Balance at end of the period	$ 197,800

Inventories (Details) - USD ($) $ in Thousands	9 Months Ended
Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Inventories
Work-in-process	$ 6,937	$ 3,308
Finished goods	335	108
Total inventories	7,272	$ 3,416
Inventory write-downs	$ 0

Commitments and Contingencies (Details)	Sep. 30, 2017 lawsuit
Commitments and Contingencies
Number of purported securities class action lawsuits	3
Number of purported securities class action lawsuits naming additional company officers as defendants	1