0001178879-22-000006 | 10-K | XBRL Viewer

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Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 245,197	$ 163,240
Investments in marketable securities	237,299	320,029
Accounts receivable	52,672	46,923
Inventories	26,818	19,556
Prepaid expenses and other current assets	34,848	29,721
Total current assets	596,834	579,469
Operating lease right-of-use assets, net	20,586	23,296
Property and equipment, less accumulated depreciation of $19,882 and $14,487 at December 31, 2021 and December 31, 2020, respectively	42,496	43,863
In-process research & development	23,000	23,000
Goodwill	197,797	197,797
Other non-current assets	24,427	19,095
Total Assets	905,140	886,520
Current liabilities:
Accounts payable	21,513	17,063
Accrued expenses and other current liabilities	98,153	96,841
Contingent consideration payable	18,900	8,900
Operating lease liabilities	7,409	6,872
Total current liabilities	145,975	129,676
Deferred reimbursements	5,906	7,406
Long-term debt	389,357	389,254
Contingent consideration payable	1,439	16,925
Deferred income taxes	4,930	4,896
Operating lease liabilities	43,363	45,604
Other non-current liabilities	6,801	6,379
Total liabilities	597,771	600,140
Commitments and contingencies
Stockholders' equity:
Common stock, $0.01 par value, 500,000,000 shares authorized, 278,912,800 and 262,063,461 shares issued and outstanding at December 31, 2021 and December 31, 2020, respectively	2,808	2,650
Additional paid-in capital	2,595,419	2,308,578
Accumulated other comprehensive gain (loss):
Foreign currency translation adjustment	5,251	8,412
Unrealized loss on available-for securities	(270)	(185)
Warrants	83	12,387
Accumulated deficit	(2,295,922)	(2,045,462)
Total stockholders' equity	307,369	286,380
Total Liabilities and Stockholders' Equity	$ 905,140	$ 886,520

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Accumulated depreciation of property and equipment	$ 19,882	$ 14,487
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	500,000,000	500,000,000
Common stock, shares issued (in shares)	278,912,800	262,063,461
Common stock, shares outstanding (in shares)	278,912,800	262,063,461

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Statement [Abstract]
Net product sales	$ 305,514	$ 260,886	$ 182,237
Cost of goods sold	34,466	31,044	21,963
Gross profit	271,048	229,842	160,274
Operating expenses:
Research and development	272,049	308,443	286,378
Selling, general, and administrative	192,710	156,407	169,861
Changes in fair value of contingent consideration payable	6,514	3,144	3,297
Depreciation and amortization	6,209	8,846	4,775
Total operating expenses	477,482	476,840	464,311
Loss from operations	(206,434)	(246,998)	(304,037)
Other (expense) income:
Interest income	509	3,226	10,249
Interest expense	(32,471)	(22,425)	(18,872)
Loss on exchange of convertible notes	0	0	(40,624)
Loss on extinguishment of debt	(257)	(7,276)	0
Other expense	(2,901)	(781)	(2,626)
Loss before income tax	(241,554)	(274,254)	(355,910)
Income tax expense	(8,906)	(2,598)	(478)
Net loss attributable to common stockholders	$ (250,460)	$ (276,852)	$ (356,388)
Net loss attributable to common stockholders per common share - basic (in dollars per share)	$ (0.92)	$ (1.07)	$ (1.48)
Net loss attributable to common stockholders per common share - diluted (in dollars per share)	$ (0.92)	$ (1.07)	$ (1.48)
Weighted-average common shares outstanding - basic (in shares)	271,421,986	258,867,380	240,421,001
Weighted-average common shares outstanding - diluted (in shares)	271,421,986	258,867,380	240,421,001

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (250,460)	$ (276,852)	$ (356,388)
Other comprehensive (loss) gain:
Foreign currency translation adjustment (loss) gain, net of tax impact of $0, $1,552, and $889, respectively	(3,161)	5,627	2,290
Unrealized (loss) gain on available-for-sale securities, net of tax impact of $0, $(50), and $182, respectively	(85)	(225)	467
Other comprehensive (loss) gain	(3,246)	5,402	2,757
Comprehensive loss	$ (253,706)	$ (271,450)	$ (353,631)

- Definition

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

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+ Details

Consolidated Statements of Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Foreign currency translation gain (loss), tax impact	$ 0	$ 1,552	$ 889
Available-for-sale securities, tax expense (benefit)	$ 0	$ (50)	$ 182

Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Warrants	Other Comprehensive Gain (Loss)	Accumulated Deficit
Balance (in shares) at Dec. 31, 2018		189,383,924
Balance at Dec. 31, 2018	$ 342,912	$ 1,942	$ 1,740,061	$ 13,063	$ 68	$ (1,412,222)
Increase (Decrease) in Stockholders' Equity
Stock options exercised, net (in shares)	1,967,000	1,967,087
Stock options exercised, net	$ 11,476	$ 20	11,456
Stock issued from equity financing (in shares)		18,720,930
Stock issued from equity financing	188,994	$ 187	188,807
Restricted stock tax vesting (in shares)		477,198
Employee withholding taxes related to restricted stock unit vesting	(3,235)		(3,235)
Stock issued for contingent consideration (in shares)		771,804
Stock issued for contingent consideration	9,316
Stock-based compensation	44,430		44,430
Warrants exercised (in shares)		101,787
Warrants exercised	812	$ 1	1,487	(676)
Equity component of the convertible notes (in shares)		43,995,139
Equity component of the convertible notes	215,476
Termination of capped call confirmations	19,875		19,875
Unrealized holding gain on available-for-sale securities	467				467
Foreign currency translation adjustment	2,290				2,290
Net loss	(356,388)					(356,388)
Balance (in shares) at Dec. 31, 2019		255,417,869
Balance at Dec. 31, 2019	$ 476,425	$ 2,598	2,227,225	12,387	2,825	(1,768,610)
Increase (Decrease) in Stockholders' Equity
Stock options exercised, net (in shares)	5,243,000	5,233,672
Stock options exercised, net	$ 42,282	$ 52	42,230
Restricted stock tax vesting (in shares)		1,411,920
Employee withholding taxes related to restricted stock unit vesting	(10,028)		(10,028)
Stock-based compensation	49,151		49,151
Unrealized holding gain on available-for-sale securities	(225)				(225)
Foreign currency translation adjustment	5,627				5,627
Net loss	$ (276,852)					(276,852)
Balance (in shares) at Dec. 31, 2020	262,063,461	262,063,461
Balance at Dec. 31, 2020	$ 286,380	$ 2,650	2,308,578	12,387	8,227	(2,045,462)
Increase (Decrease) in Stockholders' Equity
Stock options exercised, net (in shares)	1,483,000	1,461,189
Stock options exercised, net	$ 10,228	$ 15	10,213
Stock issued from equity financing	199,747	$ 112	199,552	83
Restricted stock tax vesting (in shares)		1,064,135
Employee withholding taxes related to restricted stock unit vesting	(15,009)		(15,009)
Stock-based compensation	57,838		57,838
Warrants exercised (in shares)		2,554,999
Warrants exercised	19,230	$ 26	31,591	(12,387)
Equity component of the convertible notes	2,661
Unrealized holding gain on available-for-sale securities	(85)				(85)
Foreign currency translation adjustment	(3,161)				(3,161)
Net loss	$ (250,460)					(250,460)
Balance (in shares) at Dec. 31, 2021	278,912,800	278,912,800
Balance at Dec. 31, 2021	$ 307,369	$ 2,808	$ 2,595,419	$ 83	$ 4,981	$ (2,295,922)

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating activities
Net loss	$ (250,460)	$ (276,852)	$ (356,388)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of debt discount and deferred financing	2,490	1,794	2,546
Depreciation and amortization	6,209	8,846	4,775
Stock-based compensation	57,838	49,151	44,430
Loss on exchange of convertible notes	0	0	40,624
Loss on extinguishment of debt	257	7,276	0
Non-cash changes in the fair value of contingent consideration payable	6,514	3,144	3,297
Foreign currency remeasurement loss	3,565	5,471	254
Non-cash deferred taxes	34	(155)	(1,415)
Other	0	99	(149)
Changes in operating assets and liabilities:
Accounts receivable	(8,189)	(11,219)	(11,114)
Inventories	(7,790)	(4,639)	(5,114)
Prepaid expenses and other current assets	(5,919)	(8,766)	(3,287)
Accounts payable, accrued expenses, and other current liabilities	7,430	(10,610)	46,742
Other non-current assets and liabilities	(2,617)	4,420	(10,117)
Deferred reimbursements	(1,500)	(1,250)	(5,500)
Payment of contingent consideration	(10,353)	0	0
Net cash used in operating activities	(202,491)	(233,290)	(250,416)
Investing activities
Sale and redemption of marketable securities	424,043	354,826	499,047
Purchases of marketable securities	(341,398)	(365,178)	(383,882)
Capital expenditures	(3,884)	(3,227)	(20,012)
Net cash provided by (used in) investing activities	78,761	(13,579)	95,153
Financing activities
Proceeds from issuance of common stock from equity financing and pre-funded warrants, net of issuance costs	199,750	0	0
Proceeds from issuance of common stock, net of issuance costs	0	0	188,994
Payment of long-term debt	0	(155,249)	0
Proceeds from long-term debt, net of issuance costs	0	385,929	0
Payment of finance leases	(479)	(76)	(420)
Payments of employee withholding taxes related to restricted stock unit vesting	(15,009)	(10,028)	(3,235)
Proceeds from termination of capped call confirmations	0	0	19,875
Proceeds from stock options exercised, net	10,228	42,282	11,476
Proceeds from warrants exercised, net	19,230	0	812
Payment of contingent consideration	(1,647)	0	0
Net cash provided by financing activities	212,073	262,858	217,502
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	(5,049)	3,830	1,729
Net increase in cash, cash equivalents, and restricted cash	83,294	19,819	63,968
Cash, cash equivalents, and restricted cash at the beginning of the year	166,162	146,343	82,375
Cash, cash equivalents, and restricted cash at the end of the year	249,456	166,162	146,343
Supplemental disclosures of cash flow information
Tenant improvements paid through lease incentive	300	470	19,388
Cash paid during the period for interest	30,468	24,683	16,966
Contingent consideration paid in shares	0	0	9,316
Capital expenditures unpaid at the end of period	1,448	985	1,865
Cash paid for taxes	$ 20,032	$ 10,371	$ 691

Description of Business	12 Months Ended
Description of Business	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business Amicus Therapeutics, Inc. (the "Company") is a global, patient-dedicated biotechnology company focused on discovering, developing, and delivering novel medicines for rare diseases. The Company has a portfolio of product opportunities including the first, oral monotherapy for Fabry disease that has achieved widespread global approval and a differentiated biologic for Pompe disease, that is under review with the U.S. Food and Drug Administration ("FDA") as well as the European Medicines Agency ("EMA"). We are committed to discovering and developing next generation therapies in Fabry and Pompe diseases. The cornerstone of the Company's portfolio is Galafold® (also referred to as "migalastat"), the first and only approved oral precision medicine for people living with Fabry disease who have amenable genetic variants. Migalastat is currently approved under the trade name Galafold® in the United States ("U.S."), European Union ("E.U."), United Kingdom ("U.K."), and Japan, with multiple additional approvals granted and applications pending in several geographies around the world. The lead biologics program of the Company's pipeline is Amicus Therapeutics GAA ("AT-GAA", also known as ATB200/AT2221, or cipaglucosidase alfa/miglustat), a novel, two-component, potential best-in-class treatment for Pompe disease. In February 2019, the FDA granted Breakthrough Therapy designation ("BTD") to AT-GAA for the treatment of late onset Pompe disease. In September 2021, the FDA set the Prescription Drug User Fee Act ("PDUFA") target action date of May 29, 2022 for the New Drug Application ("NDA") for miglustat and July 29, 2022 for the Biologics License Application ("BLA") for cipaglucosidase alfa. The EMA validated the Marketing Authorization Application (“MAA”) in the fourth quarter of 2021. On February 24, 2022, the Company announced, with ARYA Sciences Acquisition Corp IV ("ARYA"), a special purpose acquisition company (or "SPAC"), sponsored by Perceptive Advisors, it has agreed to mutually terminate the previously announced definitive business combination agreement, originally executed in September 2021. Additionally, in September 2021, the Company entered into securities purchase agreements with certain investors for the private placement of an aggregate of 11,296,660 shares of the Company's common stock, at a purchase price of $10.18 per share, and pre-funded warrants to purchase an aggregate of 8,349,705 shares of common stock, at a purchase price of $10.17 per pre-funded warrant. The net proceeds from these private placements were approximately $199.8 million. The Company expects to use the net proceeds to further fund initiatives in the global commercialization of Galafold® and the anticipated global launch of AT-GAA and to further support the Company's discovery work on next generation therapies in Fabry and Pompe diseases. The Company's operations have not been significantly impacted by the novel coronavirus (“COVID-19”) pandemic to date. However, the Company observed increased lag times between patient identification and Galafold® initiation due to the resurgence of COVID-19 in 2021. The Company has maintained operations in all geographies, secured its global supply chain for its commercial and clinical products, as well as maintained the operational integrity of its clinical trials, with minimal disruptions. Whether the Company will continue to operate without any significant disruptions will depend on the continued health of its employees, the ongoing demand for Galafold® and the continued operation of its global supply chain. The Company has continued to provide uninterrupted access to medicines for those in need of treatment, while prioritizing the health and safety of its global workforce. However, the Company's results of operations in future periods may be negatively impacted by unknown future impacts from the COVID-19 pandemic. The Company had an accumulated deficit of $2.3 billion as of December 31, 2021 and anticipates incurring losses through the fiscal year ending December 31, 2022 and beyond. The Company has historically funded its operations through stock offerings, Galafold® revenues, debt issuances, collaborations, and other financing arrangements. Based on its current operating model, the Company believes that the current cash position, which includes expected revenues, and net proceeds from the September 2021 private placement of securities, is sufficient to fund the Company's operations and ongoing research programs to achieve self-sustainability. Potential impacts of the COVID-19 pandemic, business development collaborations, pipeline expansion, and investment in manufacturing capabilities could impact the Company's future capital requirements.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Basis of Presentation

The Company has prepared the accompanying Consolidated Financial Statements in accordance with U.S. generally accepted accounting principles ("U.S. GAAP") and include all adjustments necessary for the fair presentation of the Company's financial position for the periods presented.

Consolidation

The Consolidated Financial Statements include the accounts of the Company and its subsidiaries. Intercompany accounts and transactions are 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.

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.

Additionally, the Company assessed the impact COVID-19 pandemic has had on its operations and financial results as of December 31, 2021 and through the issuance of these financial statements. The Company’s analysis was informed by the facts and circumstances as they were known to the Company. This assessment considered the impact COVID-19 may have on financial estimates and assumptions that affect the reported amounts of assets and liabilities and revenue and expenses.

Cash, Cash Equivalents, Marketable Securities, and Restricted Cash

The Company considers all highly liquid investments purchased with a maturity of three months or less at the date of acquisition to be cash equivalents. Marketable securities consist of fixed income investments with a maturity of greater than three months and other highly liquid investments that can be readily purchased or sold using established markets. These investments are classified as available-for-sale and are reported at fair value on the Company's Consolidated Balance Sheets. Unrealized holding gains and losses are reported within comprehensive income (loss) in the Statements of Comprehensive Loss. Fair value is based on available market information including quoted market prices, broker or dealer quotations, or other observable inputs.

Restricted cash consists primarily of funds held to satisfy the requirements of certain agreements that are restricted in their use and is included in other current assets and other non-current assets on the Company's Consolidated Balance Sheets.

Concentration of Credit Risk

The Company's financial instruments that are exposed to concentration of credit risk consist primarily of cash, 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 its cash, cash equivalents, or marketable securities.

The Company is subject to credit risk from its accounts receivable related to its product sales of Galafold®. The Company's accounts receivable at December 31, 2021 have arisen from product sales primarily in Europe and the U.S. 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. As of December 31, 2021, the Company recorded an allowance for doubtful accounts of $0.2 million.

Property and Equipment

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

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

Revenue Recognition

The Company’s net product sales consist of sales of Galafold® for the treatment of Fabry disease. The Company has recorded revenue on sales where Galafold® is available either on a commercial basis or through a reimbursed early access program ("EAP"). Orders for Galafold® are generally received from distributors and pharmacies, with the ultimate payor often a government authority. In 2021, one customer accounted for 24% of net product sales and 14% of accounts receivable from product sales. In 2020, one customer accounted for 25% of net product sales and 12% of accounts receivable from product sales.

The Company recognizes revenue when its performance obligations to its customers have been satisfied, which occurs at a point in time when the pharmacies or distributors obtain control of Galafold®. The transaction price is determined based on fixed consideration in the Company's customer contracts and is recorded net of estimates for variable consideration, which are third party discounts and rebates. The identified variable consideration is recorded as a reduction of revenue at the time revenue from the sale of Galafold® is recognized. The Company recognizes revenue to the extent that it is probable that a significant revenue reversal will not occur in a future period. These estimates may differ from actual consideration received. The Company evaluates these estimates each reporting period to reflect known changes.

The following table summarizes the Company's net product sales from Galafold® disaggregated by geographic area:


	For the Year
(in thousands)	2021		2020		2019
U.S.	$	95,387	$	80,046	$	52,478
Ex-U.S.	210,127		180,840		129,759
Total net product sales	$	305,514	$	260,886	$	182,237

Inventories and Cost of Goods Sold

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 goods sold 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.

Fair Value Measurements

The Company records certain asset and liability balances under the fair value measurements as defined by the Financial Accounting Standard Board ("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.

Research and Development Costs

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

Interest Income and Interest Expense

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

Income Taxes

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

Other Comprehensive Income (Loss)

Components of other comprehensive income (loss) include unrealized gains and losses on available-for-sale securities and gain (loss) on foreign currency transactions and are included in the Statements of Comprehensive Loss.

Leases

The Company primarily enters into lease agreements for office space, equipment, and vehicles. The leases have varying terms, some of which could include options to renew, extend, and early terminate. The Company determines if an arrangement is a lease at contract inception. Operating leases are included in right-of-use ("ROU") assets and lease liabilities on the Consolidated Balance Sheets.

ROU assets represent the Company's right to control the use of an explicitly or implicitly identified fixed asset for a period of time and lease liabilities represent the Company's obligation to make lease payments arising from the lease. Control of an underlying asset is conveyed to the Company if the Company obtains the rights to direct the use of and to obtain substantially all of the economic benefits from using the underlying asset. ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. The Company uses its incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments.

Lease payments included in the measurement of the lease liability are comprised of fixed payments. Variable lease payments are excluded from the ROU asset and lease liability and are recognized in the period in which the obligation for those payments is incurred. Variable lease payments are presented in the Consolidated Statements of Operations in the same line item as expenses arising from fixed lease payments for operating leases. The Company has lease agreements that include lease and non-lease components, which the Company accounts for as a single lease component for all underlying asset categories.

The lease term for all of the Company's leases includes the non-cancellable period of the lease plus any additional periods covered by either a Company option to extend (or not to terminate) the lease that the Company is reasonably certain to exercise, or an option to extend (or not to terminate) the lease controlled by the lessor.

Leases with an initial term of 12 months or less are not recorded on the Consolidated Balance Sheets. The Company recognizes lease expense for these leases on a straight-line basis over the lease term. The Company applies this policy to all underlying asset categories.

Nonqualified Cash Deferral Plan

The Company's Cash Deferral Plan (the "Deferral Plan"), provides certain key employees and members of the Board of Directors as selected by the Compensation Committee of the Board of Directors of the Company (the "Compensation Committee"), with an opportunity to defer the receipt of such participant's base salary, bonus, and director's fees, as applicable. The Deferral Plan is intended to be a nonqualified deferred compensation plan that complies with the provisions of Section 409A of the Internal Revenue Code. All of the investments held in the Deferral Plan are classified as trading securities and recorded at fair value with changes in the investments' fair value recognized as earnings in the period they occur. The corresponding liability for the Deferral Plan is included in other non-current liability in the Consolidated Balance Sheets.

Equity-based Compensation

At December 31, 2021, the Company had one equity-based employee compensation plan, which is described more fully in "— Note 8. Stockholders' Equity." The Company applies the fair value method of measuring equity-based compensation, which requires a public entity to measure the cost of employee services received in exchange for an award of equity instruments based on the grant-date fair value of the award.

Loss per Common Share

The Company calculates net loss per share as a measurement of the Company's performance while giving effect to all dilutive potential common shares that were outstanding during the reporting period. The Company had a net loss for all periods presented; accordingly, the inclusion of common stock options, unvested RSUs, and certain warrants would be anti-dilutive. Therefore, the weighted average shares used to calculate both basic and diluted earnings per share are the same. See "— Note 15. Basic and Diluted Net Loss per Common Share" for further discussion on net loss per share.

Segment Information

The Company currently operates in one business segment focused on the discovery, development, and commercialization of advanced therapies to treat a range of devastating rare and orphan diseases. The Company is not organized by market and is managed and operated as one business. A single management team reports to the chief operating decision maker who comprehensively manages the entire business. The Company does not operate any separate lines of business or separate business entities with respect to its products. Accordingly, the Company does not accumulate discrete financial information with respect to separate service lines, and thus there is one reporting unit.

Business Combinations

The Company assigns fair value to the tangible and intangible assets acquired and liabilities assumed based upon their estimated fair values on the acquisition date from acquired businesses. The purchase price allocation process requires management to make significant estimates and assumptions, especially at the acquisition date with respect to intangible assets and in-process research and development ("IPR&D"). In connection with the purchase price allocations for acquisitions, the Company estimates the fair value of contingent payments utilizing a probability-based income approach inclusive of an estimated discount rate.

Contingent Consideration Payable

Contingent consideration payments in asset acquisitions are recognized when the contingency is resolved and the consideration is paid or becomes payable. This does not apply in circumstances when the contingent consideration meets the definition of a derivative, in which case the amount becomes part of the basis in the asset acquired. Upon recognition of the contingent consideration payment, the amount is included in the cost of the acquired asset or group of assets. The Company determines the fair value of contingent acquisition consideration payable on the acquisition date using a probability-based income approach utilizing an appropriate discount rate. The short term and long term portions of the contingent consideration payable is shown on the Company's Consolidated Balance Sheets. The fair value of the contingent consideration payable will be determined each period end and the resulting change will be recorded on the Consolidated Statements of Operations.

Intangible Assets and Goodwill

The Company records goodwill in a business combination when the total consideration exceeds the fair value of the net tangible and identifiable intangible assets acquired. Purchased IPR&D is accounted for as an indefinite lived intangible asset until the underlying project is completed, at which point the intangible asset will be accounted for as a definite lived intangible asset, or abandoned, at which point the intangible asset will be written off or partially impaired. Goodwill and indefinite lived intangible assets are assessed annually for impairment and whenever events or circumstances indicate that the carrying amount of an asset may not be recoverable. The Company first assesses the qualitative factors to determine if a quantitative test is necessary. If required, or if the Company elects to bypass the qualitative assessment, a quantitative goodwill or IPR&D impairment test is conducted. If it is determined the full carrying amount of IPR&D is not recoverable, an impairment loss is recorded in the amount by which the carrying amount of the asset exceeds its fair value. If it is determined the Company's single reporting unit's carrying value, including goodwill, exceeds its fair value, an impairment loss is recorded for the difference. No indicators of impairment were noted during the years ended December 31, 2021 and December 31, 2020.

Recent Accounting Developments

ASU 2019-12 - In December 2019, the FASB issued Accounting Standard Update ("ASU") 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes ("ASU 2019-12"). This new guidance removes specific exceptions to the general principles in Topic 740. It eliminates the need for an organization to analyze whether the following applies in a given period: (i) exception to the incremental approach for intraperiod tax allocation; (ii) exceptions to accounting for basis differences when there are ownership changes in foreign investments; and (iii) exception in interim period income tax accounting for year-to-date losses that exceed anticipated losses. ASU 2019-12 also improves financial statement preparers’ application of income tax-related guidance and simplifies the following: (i) franchise taxes that are partially based on income; (ii) transactions with a government that result in a step up in the tax basis of goodwill; (iii) separate financial statements of legal entities that are not subject to tax; and (iv) enacted changes in tax laws in interim periods. ASU 2019-12 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. The Company adopted this guidance prospectively on January 1, 2021. The adoption did not have a material impact on the Company's Consolidated Financial Statements or related disclosures.

Goodwill and Intangible Assets

12 Months Ended

Dec. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Intangible Assets

As of December 31, 2021, in connection with the acquisitions, the Company had goodwill of $197.8 million and IPR&D of $23.0 million, which are reported at fair value on the Company's Consolidated Balance Sheets. 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. A goodwill impairment loss, if any, is measured as the amount by which the Company's single reporting unit's carrying value, including goodwill, exceeds its fair value. An IPR&D impairment loss, if any, is measured as the amount by which the carrying amount of the asset exceeds its fair value.

The following table represents the changes in IPR&D for the years ended December 31, 2021 and 2020, respectively:


	(in millions)
Balance at December 31, 2019	$	23.0
Change in IPR&D	—
Balance at December 31, 2020	$	23.0
Change in IPR&D	—
Balance at December 31, 2021	$	23.0

The following table represents the changes in Goodwill for the years ended December 31, 2021 and 2020, respectively:


	(in millions)
Balance at December 31, 2019	$	197.8
Change in goodwill	—
Balance at December 31, 2020	$	197.8
Change in goodwill	—
Balance at December 31, 2021	$	197.8

Cash, Cash Equivalents, Marketable Securities, and Restricted Cash

12 Months Ended

Dec. 31, 2021

Cash, Cash Equivalents, and Short-term Investments [Abstract]

Cash, Cash Equivalents, Marketable Securities, and Restricted Cash

As of December 31, 2021, the Company held $245.2 million in cash and cash equivalents and $237.3 million of marketable securities which are reported at fair value on the Company's Consolidated Balance Sheets. Unrealized holding gains and losses are generally reported within accumulated other comprehensive 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 or if an available-for-sale debt security’s fair value is determined to less than the amortized cost and the Company intends or is more than likely to sell the security before recovery and it is not considered a credit loss, such 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. If the unrealized loss of an available-for-sale debt security is determined to be a result of credit loss the Company would recognize an allowance and the corresponding credit loss would be included in earnings.

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 three months but less than one year are classified as current.

Cash, cash equivalents, and marketable securities are classified as current unless mentioned otherwise below and consisted of the following:


	As of December 31, 2021
(in thousands)	Cost		Gross Unrealized Gain		Gross Unrealized Loss		Fair Value
Cash and cash equivalents	$	245,197	$	—	$	—	$	245,197
Commercial paper	174,578		7		(54)		174,531
Corporate debt securities	32,322		—		(11)		32,311
Asset-backed securities	30,070		—		(14)		30,056
Money market	350		—		—		350
Certificate of deposit	51		—		—		51
	$	482,568	$	7	$	(79)	$	482,496
Included in cash and cash equivalents	$	245,197	$	—	$	—	$	245,197
Included in marketable securities	237,371		7		(79)		237,299
Total cash, cash equivalents, and marketable securities	$	482,568	$	7	$	(79)	$	482,496


	As of December 31, 2020
(in thousands)	Cost		Gross Unrealized Gain		Gross Unrealized Loss		Fair Value
Commercial paper	$	217,087	$	14	$	(6)	$	217,095
Cash and cash equivalents	163,240		—		—		163,240
U.S. government agency bonds	53,583		3		(4)		53,582
Corporate debt securities	39,525		4		(16)		39,513
Asset-backed securities	9,420		18		—		9,438
Money market	350		—		—		350
Certificate of deposit	51		—		—		51
	$	483,256	$	39	$	(26)	$	483,269
Included in cash and cash equivalents	$	163,240	$	—	$	—	$	163,240
Included in marketable securities	320,016		39		(26)		320,029
Total cash, cash equivalents, and marketable securities	$	483,256	$	39	$	(26)	$	483,269

For the year ended December 31, 2021 there were no realized gains or losses. For the fiscal year ended December 31, 2020, there were nominal realized gains. The cost of securities sold is based on the specific identification method.

Unrealized loss positions in the marketable securities as of December 31, 2021 and 2020 reflect temporary impairments and are not a result of credit loss. Additionally, as these positions have been in a loss position for less than twelve months and the Company does not intend to sell these securities before recovery, the losses are recognized in other comprehensive (loss) gain. The fair value of these marketable securities in unrealized loss positions was $173.4 million and $124.9 million as of December 31, 2021 and December 31, 2020, respectively.

The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the Consolidated Balance Sheets that sum to the total of the same such amounts shown in the Consolidated Statements of Cash Flows.


(in thousands)	December 31, 2021		December 31, 2020		December 31, 2019
Cash and cash equivalents	$	245,197	$	163,240	$	142,837
Restricted cash	4,259		2,922		3,506
Cash, cash equivalents, and restricted cash shown in the Consolidated Statements of Cash Flows	$	249,456	$	166,162	$	146,343

Inventories

12 Months Ended

Dec. 31, 2021

Inventory Disclosure [Abstract]

Inventories

Inventories consist of raw materials, work in process, and finished goods related to the manufacture of Galafold®. The following table summarizes the components of inventories:


(in thousands)	December 31, 2021		December 31, 2020
Raw materials	$	12,289	$	5,547
Work-in-process	10,699		7,693
Finished goods	3,830		6,316
Total inventories	$	26,818	$	19,556

The Company recorded a reserve for inventory of $1.1 million and $0.1 million as of December 31, 2021 and December 31, 2020, respectively.

Property and Equipment

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Property and Equipment

Property and equipment consist of the following:


	December 31,
(in thousands)	2021		2020
Leasehold improvements	$	24,168	$	24,146
Research equipment	16,663		15,387
Construction in progress	8,229		5,870
Computer equipment	5,720		5,546
Land	3,190		3,190
Furniture and fixtures	3,163		2,880
Computer software	1,174		1,207
Vehicles	71		124
Gross property and equipment	62,378		58,350
Less accumulated depreciation	(19,882)		(14,487)
Net property and equipment	$	42,496	$	43,863

Depreciation expense was $5.7 million and $8.4 million for the years ended December 31, 2021 and December 31, 2020, respectively.

Accrued Expenses and Other Current Liabilities

12 Months Ended

Dec. 31, 2021

Payables and Accruals [Abstract]

Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consist of the following:


	December 31,
(in thousands)	2021		2020
Accrued compensation and benefits	$	24,258	$	23,025
Accrued contract manufacturing & contract research costs	20,361		19,617
Accrued sales rebates and discounts	15,989		12,079
Accrued program fees	13,294		16,599
Accrued professional fees	9,377		3,700
Accrued taxes	6,154		11,177
Accrued royalties	4,522		6,550
Other	4,198		4,094
	$	98,153	$	96,841

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Dec. 31, 2021
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity Common Stock and Warrants As of December 31, 2021, the Company was authorized to issue 500 million shares of common stock. Dividends on common stock will be paid when, and if, declared by the board of directors. Each holder of common stock is entitled to vote on all matters that are appropriate for stockholder voting and is entitled to one vote for each share held. In September 2021, the Company entered into a securities purchase agreement with certain entities, the (“Purchase Agreements”) for the private placement of an aggregate of 11,296,660 shares of the Company’s common stock, at a purchase price of $10.18 per share, and pre-funded warrants to purchase an aggregate of 8,349,705 shares of common stock, at a purchase price of $10.17 per pre-funded warrant. Proceeds from the private placement, net of offering costs, were $199.8 million. Each pre-funded warrant has an initial exercise price of $0.01 per share and is exercisable at any time after its original issuance, subject generally to the lock-up period, at the option of each holder, in such holder’s discretion, by (i) payment in full in immediately available funds of the initial exercise price for the number of shares of common stock purchased upon such exercise or (ii) a cashless exercise, in which case the holder would receive upon such exercise the net number of shares of common stock determined according to the formula set forth in the pre-funded warrant. Certain of the Purchase Agreements provide for a lock-up period of either 60 days or nine months based on the individual agreements. During the first quarter of 2021, 1,294,999 and 1,260,000 warrants were exercised at $7.98 and $7.06 per share of common stock, respectively, resulting in gross cash proceeds of $19.2 million. As discussed in ''— Note 11. Debt'', during the first and third quarters of 2021, the Company entered into separate, privately negotiated exchange agreements with the holders of the Convertible Notes (the "Holders"). Under the terms of the exchange agreements, the Holders agreed to exchange the remaining aggregate principal amount of $2.8 million of Convertible Notes held by them in exchange for an aggregate of approximately 472,356 shares of Company common stock, par value $0.01 per share. This transaction resulted in an increase of $2.7 million and five thousand dollars to additional paid-in-capital and common stock, respectively. As discussed in ''— Note 11. Debt'', during the first and second quarters of 2019, the Company entered into separate, privately negotiated exchange agreements with a limited number of Holders. Under the terms of the exchange agreements, the Holders agreed to exchange an aggregate principal amount of $247.2 million of Convertible Notes held by them in exchange for an aggregate of approximately 44.0 million shares of Company's common stock, par value $0.01 per share. These transactions resulted in an increase of $215.0 million and four hundred forty thousand dollars to additional paid-in-capital and common stock, respectively. During the second quarter of 2019, the Company completed an underwritten equity offering and issued 18.7 million shares of its common stock at $10.75 per share, inclusive of the fully exercised option to purchase additional shares from the initial offering. This transaction resulted in net proceeds of $189.0 million, after deducting underwriting discounts and commissions and offering expenses. In March 2019, 101,787 warrants were exercised at $7.98 per share of common stock resulting in gross cash proceeds of $0.8 million. During the fourth quarter of 2018, the Company reached a clinical milestone, which was the dosing of the first patient in a Phase 3 study, related to the contingent consideration from the acquisition of Callidus Biopharma, Inc. ("Callidus"). The milestone for this event was $9.0 million, which was paid by issuance of 771,804 shares of Company common stock, par value $0.01 per share, in the first quarter of 2019. This transaction resulted in an increase of $9.3 million and eight thousand dollars to additional paid-in-capital and common stock, respectively. Nonqualified Cash Plan The Company's Deferral Plan, (the "Deferral Plan") provides certain key employees and members of the Board of Directors as selected by the Compensation Committee, with an opportunity to defer the receipt of such participant's base salary, bonus, and director's fees, as applicable. The Deferral Plan is intended to be a nonqualified deferred compensation plan that complies with the provisions of Section 409A of the Internal Revenue Code of 1986 as amended. The Company had a deferred compensation investment balance of $4.8 million and $4.1 million as of December 31, 2021 and December 31, 2020, respectively, with corresponding approximate amounts of liability. Deferral Plan investment assets are classified as trading securities and are recorded at fair value with changes in the investments' fair value recognized in accumulate other comprehensive gain (loss) in the period they occur. Deferred compensation liability amounts under the Deferral Plan are included in other long-term liabilities. Equity Incentive Plan The Company's Amended and Restated 2007 Equity Incentive Plan (the "Plan") provides for the granting of restricted stock units and options to purchase common stock in the Company to employees, directors, 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. Under the provisions of the Plan, no option will have a term in excess of 10 years. The Board of Directors, or its committee, is responsible for determining the individuals to be granted options, the number of options each individual will receive, the option price per share, and the exercise period of each option. Options granted pursuant to the Plan generally vest 25% on the first year anniversary date of grant plus an additional 1/48th for each month thereafter and may be exercised in whole or in part for 100% of the shares vested at any time after the date of grant. As of December 31, 2021, the Company has reserved up to 18,322,154 shares for issuance under the Plan.

- Definition

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

+ References

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+ Details

Share based Compensation

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Share based Compensation

Share based Compensation The Plan provides for the granting of restricted stock units and options to purchase common stock in the Company to employees, directors. 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 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.

The Plan provides for certain benefits to qualifying Plan participants who separate from service with the Company due to death, disability or "retirement" (as such term is defined under the Plan) ("Qualified Participants"). Options granted under the Plan ("Options") to a Qualified Participant shall continue to vest until the 2nd anniversary of the Qualified Participant’s separation and all vested Options held by such Qualified Participant shall remain exercisable until the earlier of the 4th anniversary of the Qualified Participant’s separation or the original expiration date of the Option. Options that are not exercised during this exercise period shall be forfeited. Time-based restricted stock units and restricted stock granted to a Qualified Participant under the Plan that was scheduled to vest within the two year period following the Qualified Participant's separation shall accelerate and be delivered upon such separation. Any time-based restricted stock units or restricted stock that would have vested after such two year period will be forfeited upon the Qualified Participant's separation. Also, per the Amendment, any performance-based restricted stock units under the Plan ("PRSUs") received by the Qualified Participant, shall remain eligible to vest after the Qualified Participant’s separation based on the actual performance of the Company through the end of the performance period applicable to any such PRSUs.

Stock Option Grants

The Company uses the fair value method of measuring stock-based compensation, using the fair value of each equity award granted. The Company chose the ‘‘straight-line’’ attribution method for allocating compensation costs and recognized the fair value of each stock option on a straight-line basis over the vesting period of the related awards.

The Company uses the Black-Scholes option pricing model when estimating the grant date fair value for stock-based awards. Use of a valuation model requires management to make certain assumptions with respect to selected model inputs. Expected volatility was based on our historical volatility since our initial public offering in May 2007. The average expected life is determined using our actual historical data. The risk-free interest rate is based on U.S. Treasury, zero-coupon issues with a remaining term equal to the expected life assumed at the date of grant. Forfeitures are estimated based on voluntary termination behavior, as well as a historical analysis of actual option forfeitures.

The 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:


	Years Ended December 31,
	2021			2020			2019
Expected stock price volatility	65.4		%	75.1		%	74.1		%
Risk free interest rate	0.6		%	1.6		%	2.4		%
Expected life of options (years)	5.40			5.67			5.68
Expected annual dividend per share	$	0.00		$	0.00		$	0.00

The weighted average grant-date fair value per share of options granted during 2021, 2020, and 2019 were $9.08, $6.40, and $6.67, respectively.

A summary of the Company's stock options for the year ended December 31, 2021 were as follows:


	Number of Shares	Weighted Average Exercise Price		Weighted Average Remaining Years	Aggregate Intrinsic Value
	(in thousands)				(in millions)
Options outstanding, December 31, 2018	15,810	$	8.63
Granted	4,091	$	10.29
Exercised	(1,967)	$	5.83
Forfeited	(879)	$	11.07
Expired	(331)	$	13.38
Options outstanding, December 31, 2019	16,724	$	9.15
Granted	4,362	$	9.98
Exercised	(5,243)	$	8.11
Forfeited	(1,376)	$	10.42
Expired	(435)	$	13.33
Options outstanding, December 31, 2020	14,032	$	9.54
Granted	3,262	$	16.53
Exercised	(1,483)	$	7.05
Forfeited	(844)	$	12.97
Expired	(236)	$	13.28
Options outstanding, December 31, 2021	14,731	$	11.08	6.4	$	30.3
Vested and unvested expected to vest, December 31, 2021	13,432	$	10.89	6.2	$	28.8
Exercisable at December 31, 2021	9,141	$	9.58	5.1	$	24.5

The aggregate intrinsic value of options exercised during the years ended December 31, 2021, 2020 and 2019 was $8.5 million, $40.9 million, and $11.8 million respectively. Cash proceeds from stock options exercised during the years ended December 31, 2021, 2020, and 2019 were $10.2 million, $42.3 million, and $11.5 million, respectively. As of December 31, 2021, the total unrecognized compensation cost related to non-vested stock options granted was $28.9 million and is expected to be recognized over a weighted average period of three years.

Restricted Stock Units and Performance-Based Restricted Stock Units (collectively "RSUs")

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 year ended December 31, 2021 is as follows:


	Number of Shares	Weighted Average Grant Date Fair Value		Weighted Average Remaining Years	Aggregate Intrinsic Value
	(in thousands)				(in millions)
Non-vested units as of December 31, 2018	3,712	$	10.59
Granted	3,526	$	10.92
Vested	(921)	$	8.49
Forfeited	(525)	$	10.52
Non-vested units as of December 31, 2019	5,792	$	11.18
Granted	4,692	$	11.29
Vested	(2,164)	$	10.70
Forfeited	(1,240)	$	11.14
Non-vested units as of December 31, 2020	7,080	$	11.35
Granted	3,191	$	16.94
Vested	(1,863)	$	15.77
Forfeited	(1,067)	$	12.82
Non-vested units as of December 31, 2021	7,341	$	13.90	2.3	$	84.8

For the year ended December 31, 2021, 1,863,436 RSUs have vested and all non-vested units are expected to vest over their normal term. As of December 31, 2021, there was $47.6 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 two years.

Compensation Expense Related to Equity Awards

The following table summarizes information related to compensation expense recognized in the Consolidated Statements of Operations related to the equity awards:


	Years Ended December 31,
(in thousands)	2021		2020		2019
Research and development expense	$	17,340	$	20,817	$	17,575
Selling, general, and administrative expense	40,498		28,334		26,855
Total equity compensation expense	$	57,838	$	49,151	$	44,430

Assets and Liabilities Measured at Fair Value

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

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 December 31, 2021 are identified in the following tables:


(in thousands)	Level 2		Total
Assets:
Commercial paper	$	174,531	$	174,531
Corporate debt securities	32,311		32,311
Asset-backed securities	30,056		30,056
Money market funds	5,150		5,150
	$	242,048	$	242,048


(in thousands)	Level 2		Level 3		Total
Liabilities:
Contingent consideration payable	$	—	$	20,339	$	20,339
Deferred compensation plan liability	4,800		—		4,800
	$	4,800	$	20,339	$	25,139


(in thousands)	Level 2		Total
Assets:
Commercial paper	$	217,095	$	217,095
U.S. government agency bonds	53,582		53,582
Corporate debt securities	39,513		39,513
Asset-backed securities	9,438		9,438
Money market funds	4,427		4,427
	$	324,055	$	324,055


(in thousands)	Level 2		Level 3		Total
Liabilities:
Contingent consideration payable	$	—	$	25,825	$	25,825
Deferred compensation plan liability	4,078		—		4,078
	$	4,078	$	25,825	$	29,903

Previously, the Company's Convertible Notes fell into the Level 2 category within the fair value level hierarchy. The fair value was determined using broker quotes in a non-active market for valuation. As noted in ''— Note 11. Debt," the Convertible Notes were fully settled during the third quarter of 2021.

The Company’s Senior Secured Term Loan due 2026 falls into the Level 2 category within the fair value level hierarchy and the fair value was determined using quoted prices for similar liabilities in active markets, as well as inputs that are observable for the liability (other than quoted prices), such as interest rates that are observable at commonly quoted intervals. The carrying value of the Senior Secured Term Loan due 2026 approximates the fair value.

The Company did not have any Level 3 assets as of December 31, 2021 or December 31, 2020.

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 an 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 year ended December 31, 2021. No transfers of assets between Level 1 and Level 2 of the fair value measurement hierarchy occurred during the year ended December 31, 2021.

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. Gains and losses are included in the Consolidated Statements of Operations.

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 following significant unobservable inputs were used in the valuation of the contingent consideration payable of Callidus for the ATB-200 Pompe disease program:

Contingent Consideration Liability

Fair Value as of December 31, 2021

Valuation Technique

Unobservable Input

Range

(in thousands)

Discount rate

7.5%

Clinical and regulatory milestones

18,883

Probability weighted discounted cash flow

Probability of achievement of milestones

75%-88%

Projected year of payments

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 Company reached regulatory milestone in September 2021 associated with FDA approval of the first BLA and in November 2021 associated with EMA validation of the MAA, both related to the contingent consideration of Callidus for the ATB-200 Pompe disease program. The satisfaction of these milestones resulted in the collective milestone payment of $12.0 million, which was payable in cash, resulting in a decrease in the current portion of the contingent consideration liability on the Consolidated Balance Sheets.

The following table shows the change in the balance of contingent consideration payable for the year ended December 31, 2021 and December 31, 2020, respectively:


	Years ended December 31,
(in thousands)	2021		2020
Balance, beginning of the period	$	25,825	$	22,681
Changes in fair value during the period, included in the Consolidated Statements of Operations	6,514		3,144
Payment of contingent consideration in cash	(12,000)		—
Balance, end of the period	$	20,339	$	25,825

- 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

Debt

12 Months Ended

Dec. 31, 2021

Debt Disclosure [Abstract]

Debt

The Company's debt consists of the following:


(in thousands)	December 31, 2021		December 31, 2020
Senior Secured Term Loan due 2026:
Principal	$	400,000	$	400,000
Less: debt discount (1)	(6,074)		(7,434)
Less: deferred financing (1)	(4,569)		(5,592)
Net carrying value of the Senior Secured Term Loan	$	389,357	$	386,974

Convertible Notes:
Principal	$	—	$	2,825
Less: debt discount (1)	—		(518)
Less: deferred financing (1)	—		(27)
Net carrying value of the Convertible Notes	$	—	$	2,280

Net carrying value of Long-term debt	$	389,357	$	389,254

_____________________________

(1) Included in the Consolidated Balance Sheets within long-term debt and amortized to interest expense over the remaining life of the Convertible Notes and Senior Secured Term Loan using the effective interest rate method.

Senior Secured Term Loan due 2026

In July 2020, the Company entered into a definitive agreement for a $400 million credit facility with Hayfin Capital Management (“Senior Secured Term Loan due 2026”) with an interest rate equal to 3-month LIBOR, subject to a 1% floor, plus 6.5% per annum and requires interest-only payments until mid-2024. The Senior Secured Term Loan due 2026 will be repaid in nine quarterly payments of $44.4 million, starting on July 2024 with the final balance due on the maturity date in July 2026. This transaction resulted in net proceeds of $385.9 million, after deducting fees and expenses. There were no warrants or equity conversion features associated with the Senior Secured Term Loan due 2026. The Company used the proceeds to voluntarily settle the Senior Secured Term Loan with BioPharma Credit PLC, which included the $150 million principal, $1.1 million accrued interest, and $5.2 million in early settlement premiums. As a result of this early extinguishment, the Company recognized a loss on extinguishment of debt of $7.3 million in the Consolidated Statements of Operations.

The Senior Secured Term Loan due 2026 is subject to mandatory prepayment provisions that require prepayment upon a change of control, the incurrence of certain additional indebtedness, asset sale, or an event of loss, subject to certain conditions set forth in the Senior Secured Term Loan due 2026. The Company may prepay the Senior Secured Term Loan due 2026 in whole, at its option at any time. Any prepayment of the Senior Secured Term Loan due 2026 is subject to certain make-whole premiums and prepayment premiums, the latter of which decrease until the fourth anniversary of the transaction date at which point no prepayment penalty shall exist. The obligations under the Senior Secured Term Loan due 2026 are secured by a first lien security interest in certain assets of the Company. The Senior Secured Term Loan due 2026 contains certain customary representations and warranties, affirmative and negative covenants and events of default applicable to the Company. The Senior Secured Term Loan due 2026 also contains a minimum liquidity covenant of $75 million, and an incremental minimum consolidated revenue covenant, measured as of the previous four consecutive fiscal quarters. The minimum consolidated revenue covenant ranges from $140 million, beginning March 31, 2021, and peaks at $225 million by June 30, 2023, continuing at that level until the Senior Secured Term Loan due 2026 is repaid. If an event of default occurs and is continuing, Hayfin Capital Management may declare all amounts outstanding under the Senior Secured Term Loan due 2026 to be immediately due and payable.

Convertible Notes

In December 2016, the Company issued at par value $250 million aggregate principal amount of Convertible Notes, which included the exercise in full of the $25 million over-allotment option granted to the initial purchasers of the Convertible Notes in a private offering to qualified institutional buyers pursuant to Rule 144A under the Securities Act (the "Note Offering"). Interest was payable semiannually on June 15 and December 15 of each year, beginning on June 15, 2017. The Convertible Notes would mature on December 15, 2023, unless earlier repurchased, redeemed, or converted in accordance with their terms. The Convertible Notes were 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. The net proceeds from the Note Offering were $243.0 million, after deducting fees and expenses. 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. 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 Convertible Notes were initially convertible into approximately 40.8 million 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 represented a conversion price of approximately $6.12 per share of common stock, subject to adjustment under certain conditions.

During the first and second quarters of 2019, the Company entered into separate, privately negotiated Exchange Agreements with a limited number of Holders. Under the terms of the Exchange Agreements, the limited number of Holders agreed to exchange an aggregate principal amount of $247.2 million of Convertible Notes held by them in exchange for an aggregate of approximately 44.0 million shares of Company common stock, par value $0.01 per share. In addition, pursuant to the Exchange Agreements, the Company made aggregate cash payments of $1.3 million to the limited number of Holders to satisfy accrued and unpaid interest to the closing date of the transactions, along with cash in lieu of fractional shares. These transactions resulted in $215.0 million in additional paid-in-capital and common stock of $0.4 million on the Consolidated Balance Sheets as of December 31, 2019. Additionally, the Company recognized a loss on the exchange of debt of $40.6 million on the Consolidated Statements of Operations during the year ended December 31, 2019.

During the first and second quarter of 2019, the Company terminated the Capped Call Confirmations related to the exchange of the Convertible Notes for proceeds of $19.9 million.

During the first and third quarters of 2021, the Company entered into separate, privately negotiated exchange agreements with a limited number of Holders. Under the terms of the Exchange Agreements, the Holders agreed to exchange the remaining aggregate principal amount of $2.8 million of Convertible Notes held by them in exchange for an aggregate of approximately 472,356 shares of Company common stock, par value $0.01 per share. This transaction resulted in $2.7 million in additional paid-in-capital and common stock of five thousand dollars on the Consolidated Balance Sheets as of December 31, 2021. Additionally, the Company recognized a net loss from extinguishment of debt of $0.3 million in the Consolidated Statements of Operations for the year ended December 31, 2021.

Interest Expense

The following table sets forth interest expense recognized related to the Company's debt for the years ended December 31, 2021 and 2020 respectively:


(in thousands, except interest rate amounts)	December 31, 2021			December 31, 2020
Contractual interest expense	$	30,473		$	20,933
Amortization of debt discount	$	1,462		$	1,267
Amortization of deferred financing	$	1,028		$	527
Effective interest rate of the liability component, Convertible Notes	—		%	10.6		%
Effective interest rate of the liability component, Senior Secured Term Loan due 2026	8.4		%	8.4		%

- Definition

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

+ References

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+ Details

Leases

12 Months Ended

Dec. 31, 2021

Leases [Abstract]

Leases

The Company currently has operating leases for office and research laboratory space, equipment, and vehicles under agreements expiring at various dates through 2044, which include renewal options on leases which the Company is reasonably certain to exercise.

For the years ended December 31, 2021, and 2020, operating lease expense was $10.0 million and $11.1 million and variable lease expense was $2.1 million and $1.8 million, respectively. For the years ended December 31, 2021, and 2020, the Company paid $8.4 million and $9.6 million, respectively, for amounts included in the measurement of operating lease liabilities and recorded $0.3 million and $1.7 million, respectively, of right-of-use assets and $0.3 million and $0.5 million, respectively, of tenant improvements paid through lease incentives in exchange for new operating lease liabilities.

Commitments under finance leases are not significant for the year ended December 31, 2021.

Supplemental balance sheet information related to operating leases were as follows:


(in thousands, except year and discount rate amounts)	December 31, 2021			December 31, 2020
Operating lease ROU assets, net	$	20,586		$	23,296

Current portion of the operating lease liabilities	$	7,409		$	6,872
Non-current portion of the operating lease liabilities	43,363			45,604
Total operating lease liability	$	50,772		$	52,476

Weighted-average remaining lease terms (years)	19.6			19.8
Weighted-average discount rate	13.1		%	13.0		%

At December 31, 2021, the future minimum operating lease payments were as follows:


(in thousands)	Operating Lease
2022	$	8,514
2023	8,622
2024	8,347
2025	8,304
2026	8,454
Thereafter	145,948
Total lease payments	188,189
Less lease incentives	(28,939)
Less imputed interest	(108,478)
Total operating lease liability	$	50,772

As of December 31, 2021, the Company has an additional operating lease for office space that has not yet commenced, with minimum lease payments of $15.1 million. This operating lease commenced during the first quarter of 2022 with a lease term of ten years.

Income Taxes

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Income Taxes

For financial reporting purposes, income (loss) before income taxes includes the following components:


	Years Ended December 31,
(in thousands)	2021		2020		2019
United States	$	(333,571)	$	(365,332)	$	(393,955)
Foreign	92,017		91,078		38,045
Total	$	(241,554)	$	(274,254)	$	(355,910)

Following were the components of income tax expense (benefit) for the years ended December 31, 2021, 2020, and 2019:


	Years Ended December 31,
(in thousands)	2021		2020		2019
Current
Federal	$	—	$	—	$	—
State	—		—		—
Foreign	8,857		4,163		2,877
Deferred
Federal	15		(1,410)		(984)
State	34		(155)		(1,415)
Foreign	—		—		—
Total	$	8,906	$	2,598	$	478

A reconciliation of the statutory tax rates and the effective tax rates for the years ended December 31, 2021, 2020, and 2019 are as follows:


	Years Ended December 31,
	2021		2020		2019
Statutory rate	(21)	%	(21)	%	(21)	%
State taxes, net of federal benefit	—		—		—
Nondeductible IPR&D	—		—		—
Contingent consideration	—		—		—
Tax credits	(9)		(7)		(16)
Impact of foreign operations	3		4		9
Nondeductible executive compensation	2		2		1
Nondeductible debt conversion	—		—		(1)
Other	1		—		(1)
Valuation allowance	28		23		29
Net	4	%	1	%	—	%

On December 22, 2017, the U.S. government enacted the Tax Cuts and Jobs Act ("Tax Act"). The Tax Act significantly revises U.S. tax law by, among other provisions, lowering the U.S. federal statutory income tax rate to 21%, imposing a mandatory one-time transition tax on previously deferred foreign earnings, and eliminating or reducing certain income tax deductions. The Tax Act also introduced an additional U.S. tax on certain non-U.S. subsidiaries’ earnings which are considered to be Global Intangible Low Taxed Income (referred to as "GILTI"). After consideration of the relevant guidance and completing the accounting for the tax effects of the Tax Act, the Company has elected to treat GILTI as a period cost.

The Company recorded income tax expense of $8.9 million in 2021 for taxes in foreign jurisdictions. Due to the loss position and full valuation allowance, there is nominal tax expense in 2021 for taxes in U.S. federal and state jurisdictions.

The Company had minimal interest or penalties related to UK corporate taxes during the period ended December 31, 2021 and did not accrue for any interest or penalties as of December 31, 2021. The Company had a nominal accrual for uncertain tax positions as of December 31, 2021. Tax returns for years 2016 through 2020 are open to examination by tax authorities. The Company is also subject to examination in any period for which it has net operating losses.

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


	Years Ended December 31,
(in thousands)	2021		2020
Deferred tax assets
Intellectual property	$	105,453	$	68,209
Amortization/depreciation	277		489
Research tax credit	205,095		182,651
Net operating loss carry forwards	334,762		305,876
Deferred reimbursements	1,587		1,912
Non-cash stock issue	11,779		17,553
Interest carry forward limitation	8,285		5,655
Lease liability	9,105		9,235
Other	15,884		10,855
Gross deferred tax assets	692,227		602,435
Deferred tax liabilities
Business acquisition	(4,930)		(4,937)
Royalty payable	(105,453)		(68,209)
Convertible notes	—		(94)
Advanced R&D payments	(1,802)		(1,776)
Right of use asset	(3,130)		(3,420)
Total net deferred tax assets	576,912		523,999
Less: valuation allowance	(581,842)		(528,895)
Net deferred tax liability	$	(4,930)	$	(4,896)

The Company records a valuation allowance for temporary differences for which it is more likely than not that the Company will not receive future tax benefits. At December 31, 2021 and 2020, the Company recorded valuation allowances of $581.8 million and $528.9 million, respectively, representing an increase in the valuation allowance of $52.9 million in 2021, due to the uncertainty regarding the realization of such deferred tax assets, to offset the benefits of net operating losses generated during those years. The deferred tax liability related to business acquisitions pertains to the basis difference in IPR&D acquired by the Company. The Company's policy is to record a deferred tax liability related to acquired IPR&D that may eventually be realized either upon amortization of the asset when the research is completed, and a product is successfully launched or the write-off of the asset if it is abandoned or unsuccessful.

As of December 31, 2021, the Company had federal and state net operating loss carry forwards ("NOLs") of approximately $1,292 million and $1,000 million, respectively. The federal carry forward for losses generated prior to 2018 will expire in 2029 through 2037. Federal net operating losses incurred in 2018 and onward have an indefinite expiration under the 2017 Tax Act. Most of the state carry forwards generated prior to 2009 have expired through 2016. The remaining state carry forwards including those generated in 2009 through 2021 will expire in 2029 through 2040. Utilization of NOLs may be subject to a substantial limitation pursuant to Section 382 of the Internal Revenue Code of 1986, as amended as well as similar state statutes in the event of an ownership change. Such ownership changes have occurred in the past and could occur again in the future. Under Section 382 of the Internal Revenue Code of 1986, as amended, or Section 382, if a corporation undergoes an "ownership change," generally defined as a greater than 50% change (by value) in its equity ownership over a three-year period, the corporation's ability to use its pre-change NOLs and other pre-change tax attributes (such as research and development tax credits) to offset its post-change income may be limited. The Company may experience ownership changes in the future as a result of shifts in the stock ownership some of which are outside the Company's control. The Company completed a detailed study of the NOLs and determined that there was not an ownership change in excess of 50%. Ownership changes in future periods may place additional limits on the Company's ability to utilize net operating loss and tax credit carry forwards. In addition, at the state level, there may be periods during which the use of NOLs is suspended or otherwise limited, which could accelerate or permanently decrease the amount of state attributes and increase state taxes owed.

The Company also has research and experimentation and orphan drug credit carryforwards of approximately $30.3 million and $165.2 million, respectively, which will expire in the years 2021 through 2040. Deferred tax assets for these carryforwards are subject to a full valuation allowance.

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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+ Details

Collaborative Agreements	12 Months Ended
Collaborative Agreements	Dec. 31, 2021
Collaborative Agreements
Collaborative Agreements	Collaborative Agreements University of Pennsylvania In October 2018, as amended, the Company entered into a collaboration agreement with the University of Pennsylvania ("Penn") to pursue research and development of novel gene therapies. The Company's gene therapy portfolio pipeline expanded to include Pompe disease, Fabry disease, CDKL5 deficiency disorder ("CDD"), ceroid lipofuscinosis, neuronal ("CLN1"), Mucopolysaccharidosis Type IIIB ("MPSIIIB"), as well as a next generation program in Mucopolysaccharidosis Type IIIA ("MPSIIIA"). This expanded collaboration with Penn also provides the Company with exclusive disease-specific access and option rights to develop potentially disruptive new gene therapy platform technologies and programs for most LDs and a broader portfolio of other rare diseases. Under the expanded collaboration agreement with Penn, Penn is eligible to receive certain milestone, royalty and discovery research payments with respect to licensed products for each indication. Milestone payments are payable following the achievement of certain development and commercial milestone events in each indication, up to an aggregate of $88.0 million per indication. Royalty payments are based on net sales of licensed products on a licensed product-by-licensed product and country- by-country basis. The Company will provide $10.0 million each year during the five-year agreement to fund the discovery research program. GlaxoSmithKline In July 2012, as amended in November 2013, the Company entered into an agreement with GlaxoSmithKline ("GSK"), pursuant to which Amicus obtained global rights to develop and commercialize Galafold® as a monotherapy and in combination with ERT for Fabry disease (“Collaboration Agreement”). Under the terms of the Collaboration Agreement, GSK is eligible to receive post-approval and sales-based milestones up to $40 million, as well as tiered royalties in the mid-teens in eight major markets outside the U.S. The contingent milestone payments due to GSK are recorded within the short term and long term deferred reimbursements accounts on the Consolidated Balance Sheets. Sales based tiered royalties due to GSK are recorded within the cost of goods sold within the Consolidated Statements of Operations. For the year ended December 31, 2021, under the GSK collaboration agreements, the Company paid $1.5 million in sales-based milestones and the Company incurred approximately $25.4 million of royalty expenses. As of December 31, 2021, $7.4 million was recorded as deferred reimbursements and the Company recognized a liability of $4.5 million related to royalties payable to GSK in accounts payable and accrued expenses in the Consolidated Balance Sheets.

Basic and Diluted Net Loss per Common Share

12 Months Ended

Dec. 31, 2021

Earnings Per Share [Abstract]

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:


	Years Ended December 31,
(in thousands, except per share amounts)	2021		2020		2019
Numerator:
Net loss attributable to common stockholders	$	(250,460)	$	(276,852)	$	(356,388)
Denominator:
Weighted average common shares outstanding — basic and diluted	271,421,986		258,867,380		240,421,001

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:


	Years ended December 31,
(in thousands)	2021	2020	2019
Options to purchase common stock	14,731	14,032	16,724
Unvested restricted stock units	7,341	7,080	5,792
Outstanding warrants, convertible to common stock	—	2,555	2,555
Convertible notes	—	462	462
Total number of potentially issuable shares	22,072	24,129	25,533

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The Company has prepared the accompanying Consolidated Financial Statements in accordance with U.S. generally accepted accounting principles ("U.S. GAAP") and include all adjustments necessary for the fair presentation of the Company's financial position for the periods presented.
Consolidation	Consolidation The Consolidated Financial Statements include the accounts of the Company and its subsidiaries. Intercompany accounts and transactions are 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.
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. Additionally, the Company assessed the impact COVID-19 pandemic has had on its operations and financial results as of December 31, 2021 and through the issuance of these financial statements. The Company’s analysis was informed by the facts and circumstances as they were known to the Company. This assessment considered the impact COVID-19 may have on financial estimates and assumptions that affect the reported amounts of assets and liabilities and revenue and expenses.
Cash, Cash Equivalents, Marketable Securities, and Restricted Cash	Cash, Cash Equivalents, Marketable Securities, and Restricted Cash The Company considers all highly liquid investments purchased with a maturity of three months or less at the date of acquisition to be cash equivalents. Marketable securities consist of fixed income investments with a maturity of greater than three months and other highly liquid investments that can be readily purchased or sold using established markets. These investments are classified as available-for-sale and are reported at fair value on the Company's Consolidated Balance Sheets. Unrealized holding gains and losses are reported within comprehensive income (loss) in the Statements of Comprehensive Loss. Fair value is based on available market information including quoted market prices, broker or dealer quotations, or other observable inputs. Restricted cash consists primarily of funds held to satisfy the requirements of certain agreements that are restricted in their use and is included in other current assets and other non-current assets on the Company's Consolidated Balance Sheets.
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, 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 its cash, cash equivalents, or marketable securities. The Company is subject to credit risk from its accounts receivable related to its product sales of Galafold®. The Company's accounts receivable at December 31, 2021 have arisen from product sales primarily in Europe and the U.S. 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.
Property and Equipment	Property and Equipment Property and equipment are stated at cost, less accumulated depreciation. Depreciation is calculated over the estimated useful lives of the respective assets, which range from three to five years, or the lesser of the related initial term of the lease or useful life for leasehold improvements. The initial cost of property and equipment consists of its purchase price and any directly attributable costs of bringing the asset to its working condition and location for its intended use. Expenditures incurred after the fixed assets have been put into operation, such as repairs and maintenance, are charged to income in the period in which the costs are incurred. Major replacements, improvements, and additions are capitalized in accordance with Company policy.
Revenue Recognition	Revenue Recognition The Company’s net product sales consist of sales of Galafold® for the treatment of Fabry disease. The Company has recorded revenue on sales where Galafold® is available either on a commercial basis or through a reimbursed early access program ("EAP"). Orders for Galafold® are generally received from distributors and pharmacies, with the ultimate payor often a government authority. In 2021, one customer accounted for 24% of net product sales and 14% of accounts receivable from product sales. In 2020, one customer accounted for 25% of net product sales and 12% of accounts receivable from product sales. The Company recognizes revenue when its performance obligations to its customers have been satisfied, which occurs at a point in time when the pharmacies or distributors obtain control of Galafold®. The transaction price is determined based on fixed consideration in the Company's customer contracts and is recorded net of estimates for variable consideration, which are third party discounts and rebates. The identified variable consideration is recorded as a reduction of revenue at the time revenue from the sale of Galafold® is recognized. The Company recognizes revenue to the extent that it is probable that a significant revenue reversal will not occur in a future period. These estimates may differ from actual consideration received. The Company evaluates these estimates each reporting period to reflect known changes.
Inventories and Cost of Goods Sold	Inventories and Cost of Goods Sold 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 goods sold 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.
Fair Value Measurements	Fair Value Measurements The Company records certain asset and liability balances under the fair value measurements as defined by the Financial Accounting Standard Board ("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.
Research and Development Costs	Research and Development Costs Research and development costs are expensed as incurred. Research and development expense consist primarily of costs related to personnel, including salaries and other personnel related expenses, consulting fees, and the cost of facilities and support services used in drug development. Assets acquired that are used for research and development and have no future alternative use are expensed as in-process research and development.
Interest Income and Interest Expense	Interest Income and Interest Expense Interest income consists of interest earned on the Company's cash, cash equivalents, and marketable securities. Interest expense consists of interest incurred on debt and finance leases.
Income Taxes	Income Taxes The Company accounts for income taxes under the liability method. Under this method deferred income tax liabilities and assets are determined based on the difference between the financial statement carrying amounts and tax basis of assets and liabilities and for operating losses and tax credit carry forwards, using enacted tax rates in effect in the years in which the differences are expected to reverse. A valuation allowance is recorded if it is "more likely than not" that a portion or all of a deferred tax asset will not be realized.
Other Comprehensive Income (Loss)	Other Comprehensive Income (Loss) Components of other comprehensive income (loss) include unrealized gains and losses on available-for-sale securities and gain (loss) on foreign currency transactions and are included in the Statements of Comprehensive Loss.
Leases	Leases The Company primarily enters into lease agreements for office space, equipment, and vehicles. The leases have varying terms, some of which could include options to renew, extend, and early terminate. The Company determines if an arrangement is a lease at contract inception. Operating leases are included in right-of-use ("ROU") assets and lease liabilities on the Consolidated Balance Sheets. ROU assets represent the Company's right to control the use of an explicitly or implicitly identified fixed asset for a period of time and lease liabilities represent the Company's obligation to make lease payments arising from the lease. Control of an underlying asset is conveyed to the Company if the Company obtains the rights to direct the use of and to obtain substantially all of the economic benefits from using the underlying asset. ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. The Company uses its incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. Lease payments included in the measurement of the lease liability are comprised of fixed payments. Variable lease payments are excluded from the ROU asset and lease liability and are recognized in the period in which the obligation for those payments is incurred. Variable lease payments are presented in the Consolidated Statements of Operations in the same line item as expenses arising from fixed lease payments for operating leases. The Company has lease agreements that include lease and non-lease components, which the Company accounts for as a single lease component for all underlying asset categories. The lease term for all of the Company's leases includes the non-cancellable period of the lease plus any additional periods covered by either a Company option to extend (or not to terminate) the lease that the Company is reasonably certain to exercise, or an option to extend (or not to terminate) the lease controlled by the lessor. Leases with an initial term of 12 months or less are not recorded on the Consolidated Balance Sheets. The Company recognizes lease expense for these leases on a straight-line basis over the lease term. The Company applies this policy to all underlying asset categories.
Nonqualified Cash Deferral Plan	Nonqualified Cash Deferral Plan The Company's Cash Deferral Plan (the "Deferral Plan"), provides certain key employees and members of the Board of Directors as selected by the Compensation Committee of the Board of Directors of the Company (the "Compensation Committee"), with an opportunity to defer the receipt of such participant's base salary, bonus, and director's fees, as applicable. The Deferral Plan is intended to be a nonqualified deferred compensation plan that complies with the provisions of Section 409A of the Internal Revenue Code. All of the investments held in the Deferral Plan are classified as trading securities and recorded at fair value with changes in the investments' fair value recognized as earnings in the period they occur. The corresponding liability for the Deferral Plan is included in other non-current liability in the Consolidated Balance Sheets.
Equity-based Compensation	Equity-based Compensation At December 31, 2021, the Company had one equity-based employee compensation plan, which is described more fully in "— Note 8. Stockholders' Equity." The Company applies the fair value method of measuring equity-based compensation, which requires a public entity to measure the cost of employee services received in exchange for an award of equity instruments based on the grant-date fair value of the award.
Loss per Common Share	Loss per Common ShareThe Company calculates net loss per share as a measurement of the Company's performance while giving effect to all dilutive potential common shares that were outstanding during the reporting period. The Company had a net loss for all periods presented; accordingly, the inclusion of common stock options, unvested RSUs, and certain warrants would be anti-dilutive. Therefore, the weighted average shares used to calculate both basic and diluted earnings per share are the same.
Segment Information	Segment Information The Company currently operates in one business segment focused on the discovery, development, and commercialization of advanced therapies to treat a range of devastating rare and orphan diseases. The Company is not organized by market and is managed and operated as one business. A single management team reports to the chief operating decision maker who comprehensively manages the entire business. The Company does not operate any separate lines of business or separate business entities with respect to its products. Accordingly, the Company does not accumulate discrete financial information with respect to separate service lines, and thus there is one reporting unit.
Business Combinations	Business Combinations The Company assigns fair value to the tangible and intangible assets acquired and liabilities assumed based upon their estimated fair values on the acquisition date from acquired businesses. The purchase price allocation process requires management to make significant estimates and assumptions, especially at the acquisition date with respect to intangible assets and in-process research and development ("IPR&D"). In connection with the purchase price allocations for acquisitions, the Company estimates the fair value of contingent payments utilizing a probability-based income approach inclusive of an estimated discount rate.
Contingent Consideration Payable	Contingent Consideration Payable Contingent consideration payments in asset acquisitions are recognized when the contingency is resolved and the consideration is paid or becomes payable. This does not apply in circumstances when the contingent consideration meets the definition of a derivative, in which case the amount becomes part of the basis in the asset acquired. Upon recognition of the contingent consideration payment, the amount is included in the cost of the acquired asset or group of assets. The Company determines the fair value of contingent acquisition consideration payable on the acquisition date using a probability-based income approach utilizing an appropriate discount rate. The short term and long term portions of the contingent consideration payable is shown on the Company's Consolidated Balance Sheets. The fair value of the contingent consideration payable will be determined each period end and the resulting change will be recorded on the Consolidated Statements of Operations.
Intangible Assets and Goodwill	Intangible Assets and GoodwillThe Company records goodwill in a business combination when the total consideration exceeds the fair value of the net tangible and identifiable intangible assets acquired. Purchased IPR&D is accounted for as an indefinite lived intangible asset until the underlying project is completed, at which point the intangible asset will be accounted for as a definite lived intangible asset, or abandoned, at which point the intangible asset will be written off or partially impaired. Goodwill and indefinite lived intangible assets are assessed annually for impairment and whenever events or circumstances indicate that the carrying amount of an asset may not be recoverable. The Company first assesses the qualitative factors to determine if a quantitative test is necessary. If required, or if the Company elects to bypass the qualitative assessment, a quantitative goodwill or IPR&D impairment test is conducted. If it is determined the full carrying amount of IPR&D is not recoverable, an impairment loss is recorded in the amount by which the carrying amount of the asset exceeds its fair value.
Recent Accounting Developments	Recent Accounting Developments ASU 2019-12 - In December 2019, the FASB issued Accounting Standard Update ("ASU") 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes ("ASU 2019-12"). This new guidance removes specific exceptions to the general principles in Topic 740. It eliminates the need for an organization to analyze whether the following applies in a given period: (i) exception to the incremental approach for intraperiod tax allocation; (ii) exceptions to accounting for basis differences when there are ownership changes in foreign investments; and (iii) exception in interim period income tax accounting for year-to-date losses that exceed anticipated losses. ASU 2019-12 also improves financial statement preparers’ application of income tax-related guidance and simplifies the following: (i) franchise taxes that are partially based on income; (ii) transactions with a government that result in a step up in the tax basis of goodwill; (iii) separate financial statements of legal entities that are not subject to tax; and (iv) enacted changes in tax laws in interim periods. ASU 2019-12 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. The Company adopted this guidance prospectively on January 1, 2021. The adoption did not have a material impact on the Company's Consolidated Financial Statements or related disclosures.

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Revenue Disaggregated by Geographical Area

The following table summarizes the Company's net product sales from Galafold® disaggregated by geographic area:


	For the Year
(in thousands)	2021		2020		2019
U.S.	$	95,387	$	80,046	$	52,478
Ex-U.S.	210,127		180,840		129,759
Total net product sales	$	305,514	$	260,886	$	182,237

Goodwill and Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Changes in IPR&D

The following table represents the changes in IPR&D for the years ended December 31, 2021 and 2020, respectively:


	(in millions)
Balance at December 31, 2019	$	23.0
Change in IPR&D	—
Balance at December 31, 2020	$	23.0
Change in IPR&D	—
Balance at December 31, 2021	$	23.0

Schedule of Changes in Goodwill

The following table represents the changes in Goodwill for the years ended December 31, 2021 and 2020, respectively:


	(in millions)
Balance at December 31, 2019	$	197.8
Change in goodwill	—
Balance at December 31, 2020	$	197.8
Change in goodwill	—
Balance at December 31, 2021	$	197.8

Cash, Cash Equivalents, Marketable Securities, and Restricted Cash (Tables)

12 Months Ended

Dec. 31, 2021

Cash, Cash Equivalents, and Short-term Investments [Abstract]

Schedule of Cash and Available for Sale Securities

Cash, cash equivalents, and marketable securities are classified as current unless mentioned otherwise below and consisted of the following:


	As of December 31, 2021
(in thousands)	Cost		Gross Unrealized Gain		Gross Unrealized Loss		Fair Value
Cash and cash equivalents	$	245,197	$	—	$	—	$	245,197
Commercial paper	174,578		7		(54)		174,531
Corporate debt securities	32,322		—		(11)		32,311
Asset-backed securities	30,070		—		(14)		30,056
Money market	350		—		—		350
Certificate of deposit	51		—		—		51
	$	482,568	$	7	$	(79)	$	482,496
Included in cash and cash equivalents	$	245,197	$	—	$	—	$	245,197
Included in marketable securities	237,371		7		(79)		237,299
Total cash, cash equivalents, and marketable securities	$	482,568	$	7	$	(79)	$	482,496


	As of December 31, 2020
(in thousands)	Cost		Gross Unrealized Gain		Gross Unrealized Loss		Fair Value
Commercial paper	$	217,087	$	14	$	(6)	$	217,095
Cash and cash equivalents	163,240		—		—		163,240
U.S. government agency bonds	53,583		3		(4)		53,582
Corporate debt securities	39,525		4		(16)		39,513
Asset-backed securities	9,420		18		—		9,438
Money market	350		—		—		350
Certificate of deposit	51		—		—		51
	$	483,256	$	39	$	(26)	$	483,269
Included in cash and cash equivalents	$	163,240	$	—	$	—	$	163,240
Included in marketable securities	320,016		39		(26)		320,029
Total cash, cash equivalents, and marketable securities	$	483,256	$	39	$	(26)	$	483,269

Schedule of Reconciliation of Cash and Cash Equivalents and Restricted Cash


(in thousands)	December 31, 2021		December 31, 2020		December 31, 2019
Cash and cash equivalents	$	245,197	$	163,240	$	142,837
Restricted cash	4,259		2,922		3,506
Cash, cash equivalents, and restricted cash shown in the Consolidated Statements of Cash Flows	$	249,456	$	166,162	$	146,343

Inventories (Tables)

12 Months Ended

Dec. 31, 2021

Inventory Disclosure [Abstract]

Schedule of Inventories for the Period

The following table summarizes the components of inventories:


(in thousands)	December 31, 2021		December 31, 2020
Raw materials	$	12,289	$	5,547
Work-in-process	10,699		7,693
Finished goods	3,830		6,316
Total inventories	$	26,818	$	19,556

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment

Property and equipment consist of the following:


	December 31,
(in thousands)	2021		2020
Leasehold improvements	$	24,168	$	24,146
Research equipment	16,663		15,387
Construction in progress	8,229		5,870
Computer equipment	5,720		5,546
Land	3,190		3,190
Furniture and fixtures	3,163		2,880
Computer software	1,174		1,207
Vehicles	71		124
Gross property and equipment	62,378		58,350
Less accumulated depreciation	(19,882)		(14,487)
Net property and equipment	$	42,496	$	43,863

Accrued Expenses and Other Current Liabilities (Tables)

12 Months Ended

Dec. 31, 2021

Payables and Accruals [Abstract]

Schedule of Accounts Payable and Accrued Expenses

Accrued expenses and other current liabilities consist of the following:


	December 31,
(in thousands)	2021		2020
Accrued compensation and benefits	$	24,258	$	23,025
Accrued contract manufacturing & contract research costs	20,361		19,617
Accrued sales rebates and discounts	15,989		12,079
Accrued program fees	13,294		16,599
Accrued professional fees	9,377		3,700
Accrued taxes	6,154		11,177
Accrued royalties	4,522		6,550
Other	4,198		4,094
	$	98,153	$	96,841

Share based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Schedule of Fair Value of Options

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:


	Years Ended December 31,
	2021			2020			2019
Expected stock price volatility	65.4		%	75.1		%	74.1		%
Risk free interest rate	0.6		%	1.6		%	2.4		%
Expected life of options (years)	5.40			5.67			5.68
Expected annual dividend per share	$	0.00		$	0.00		$	0.00

Schedule of Stock Options Activity

A summary of the Company's stock options for the year ended December 31, 2021 were as follows:


	Number of Shares	Weighted Average Exercise Price		Weighted Average Remaining Years	Aggregate Intrinsic Value
	(in thousands)				(in millions)
Options outstanding, December 31, 2018	15,810	$	8.63
Granted	4,091	$	10.29
Exercised	(1,967)	$	5.83
Forfeited	(879)	$	11.07
Expired	(331)	$	13.38
Options outstanding, December 31, 2019	16,724	$	9.15
Granted	4,362	$	9.98
Exercised	(5,243)	$	8.11
Forfeited	(1,376)	$	10.42
Expired	(435)	$	13.33
Options outstanding, December 31, 2020	14,032	$	9.54
Granted	3,262	$	16.53
Exercised	(1,483)	$	7.05
Forfeited	(844)	$	12.97
Expired	(236)	$	13.28
Options outstanding, December 31, 2021	14,731	$	11.08	6.4	$	30.3
Vested and unvested expected to vest, December 31, 2021	13,432	$	10.89	6.2	$	28.8
Exercisable at December 31, 2021	9,141	$	9.58	5.1	$	24.5

Schedule of Non-Vested RSU Activity under the Plan

A summary of non-vested RSU activity under the Plan for the year ended December 31, 2021 is as follows:


	Number of Shares	Weighted Average Grant Date Fair Value		Weighted Average Remaining Years	Aggregate Intrinsic Value
	(in thousands)				(in millions)
Non-vested units as of December 31, 2018	3,712	$	10.59
Granted	3,526	$	10.92
Vested	(921)	$	8.49
Forfeited	(525)	$	10.52
Non-vested units as of December 31, 2019	5,792	$	11.18
Granted	4,692	$	11.29
Vested	(2,164)	$	10.70
Forfeited	(1,240)	$	11.14
Non-vested units as of December 31, 2020	7,080	$	11.35
Granted	3,191	$	16.94
Vested	(1,863)	$	15.77
Forfeited	(1,067)	$	12.82
Non-vested units as of December 31, 2021	7,341	$	13.90	2.3	$	84.8

Schedule of Equity Compensation Expenses

The following table summarizes information related to compensation expense recognized in the Consolidated Statements of Operations related to the equity awards:


	Years Ended December 31,
(in thousands)	2021		2020		2019
Research and development expense	$	17,340	$	20,817	$	17,575
Selling, general, and administrative expense	40,498		28,334		26,855
Total equity compensation expense	$	57,838	$	49,151	$	44,430

Assets and Liabilities Measured at Fair Value (Tables)

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Summary of Assets and Liabilities Subject to Fair Value Measurements


(in thousands)	Level 2		Total
Assets:
Commercial paper	$	174,531	$	174,531
Corporate debt securities	32,311		32,311
Asset-backed securities	30,056		30,056
Money market funds	5,150		5,150
	$	242,048	$	242,048


(in thousands)	Level 2		Level 3		Total
Liabilities:
Contingent consideration payable	$	—	$	20,339	$	20,339
Deferred compensation plan liability	4,800		—		4,800
	$	4,800	$	20,339	$	25,139


(in thousands)	Level 2		Total
Assets:
Commercial paper	$	217,095	$	217,095
U.S. government agency bonds	53,582		53,582
Corporate debt securities	39,513		39,513
Asset-backed securities	9,438		9,438
Money market funds	4,427		4,427
	$	324,055	$	324,055


(in thousands)	Level 2		Level 3		Total
Liabilities:
Contingent consideration payable	$	—	$	25,825	$	25,825
Deferred compensation plan liability	4,078		—		4,078
	$	4,078	$	25,825	$	29,903

Schedule of Significant Unobservable Inputs Used in the Valuation of the Contingent Consideration Payable

The following significant unobservable inputs were used in the valuation of the contingent consideration payable of Callidus for the ATB-200 Pompe disease program:

Contingent Consideration Liability

Fair Value as of December 31, 2021

Valuation Technique

Unobservable Input

Range

(in thousands)

Discount rate

7.5%

Clinical and regulatory milestones

18,883

Probability weighted discounted cash flow

Probability of achievement of milestones

75%-88%

Projected year of payments

2022

Schedule of Changes in Contingent Consideration Payable

The following table shows the change in the balance of contingent consideration payable for the year ended December 31, 2021 and December 31, 2020, respectively:


	Years ended December 31,
(in thousands)	2021		2020
Balance, beginning of the period	$	25,825	$	22,681
Changes in fair value during the period, included in the Consolidated Statements of Operations	6,514		3,144
Payment of contingent consideration in cash	(12,000)		—
Balance, end of the period	$	20,339	$	25,825

- 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

Debt (Tables)

12 Months Ended

Dec. 31, 2021

Debt Disclosure [Abstract]

Schedule of Liability Components of the Convertible Notes

The Company's debt consists of the following:


(in thousands)	December 31, 2021		December 31, 2020
Senior Secured Term Loan due 2026:
Principal	$	400,000	$	400,000
Less: debt discount (1)	(6,074)		(7,434)
Less: deferred financing (1)	(4,569)		(5,592)
Net carrying value of the Senior Secured Term Loan	$	389,357	$	386,974

Convertible Notes:
Principal	$	—	$	2,825
Less: debt discount (1)	—		(518)
Less: deferred financing (1)	—		(27)
Net carrying value of the Convertible Notes	$	—	$	2,280

Net carrying value of Long-term debt	$	389,357	$	389,254

_____________________________

Components of Total Interest Expense Recognized Related to the Convertible Notes

The following table sets forth interest expense recognized related to the Company's debt for the years ended December 31, 2021 and 2020 respectively:


(in thousands, except interest rate amounts)	December 31, 2021			December 31, 2020
Contractual interest expense	$	30,473		$	20,933
Amortization of debt discount	$	1,462		$	1,267
Amortization of deferred financing	$	1,028		$	527
Effective interest rate of the liability component, Convertible Notes	—		%	10.6		%
Effective interest rate of the liability component, Senior Secured Term Loan due 2026	8.4		%	8.4		%

Leases (Tables)

12 Months Ended

Dec. 31, 2021

Leases [Abstract]

Lease Cost

Supplemental balance sheet information related to operating leases were as follows:


(in thousands, except year and discount rate amounts)	December 31, 2021			December 31, 2020
Operating lease ROU assets, net	$	20,586		$	23,296

Current portion of the operating lease liabilities	$	7,409		$	6,872
Non-current portion of the operating lease liabilities	43,363			45,604
Total operating lease liability	$	50,772		$	52,476

Weighted-average remaining lease terms (years)	19.6			19.8
Weighted-average discount rate	13.1		%	13.0		%

Future Minimum Operating Lease Payments

At December 31, 2021, the future minimum operating lease payments were as follows:


(in thousands)	Operating Lease
2022	$	8,514
2023	8,622
2024	8,347
2025	8,304
2026	8,454
Thereafter	145,948
Total lease payments	188,189
Less lease incentives	(28,939)
Less imputed interest	(108,478)
Total operating lease liability	$	50,772

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Schedule of loss before Income Taxes

For financial reporting purposes, income (loss) before income taxes includes the following components:


	Years Ended December 31,
(in thousands)	2021		2020		2019
United States	$	(333,571)	$	(365,332)	$	(393,955)
Foreign	92,017		91,078		38,045
Total	$	(241,554)	$	(274,254)	$	(355,910)

Schedule of Income Tax Expense (Benefit)

Following were the components of income tax expense (benefit) for the years ended December 31, 2021, 2020, and 2019:


	Years Ended December 31,
(in thousands)	2021		2020		2019
Current
Federal	$	—	$	—	$	—
State	—		—		—
Foreign	8,857		4,163		2,877
Deferred
Federal	15		(1,410)		(984)
State	34		(155)		(1,415)
Foreign	—		—		—
Total	$	8,906	$	2,598	$	478

Schedule of Reconciliation of the Statutory Tax Rates and the Effective Tax Rates

A reconciliation of the statutory tax rates and the effective tax rates for the years ended December 31, 2021, 2020, and 2019 are as follows:


	Years Ended December 31,
	2021		2020		2019
Statutory rate	(21)	%	(21)	%	(21)	%
State taxes, net of federal benefit	—		—		—
Nondeductible IPR&D	—		—		—
Contingent consideration	—		—		—
Tax credits	(9)		(7)		(16)
Impact of foreign operations	3		4		9
Nondeductible executive compensation	2		2		1
Nondeductible debt conversion	—		—		(1)
Other	1		—		(1)
Valuation allowance	28		23		29
Net	4	%	1	%	—	%

Schedule of Significant Components of the Deferred Tax Assets and Liabilities

The significant components of the deferred tax assets and liabilities are as follows:


	Years Ended December 31,
(in thousands)	2021		2020
Deferred tax assets
Intellectual property	$	105,453	$	68,209
Amortization/depreciation	277		489
Research tax credit	205,095		182,651
Net operating loss carry forwards	334,762		305,876
Deferred reimbursements	1,587		1,912
Non-cash stock issue	11,779		17,553
Interest carry forward limitation	8,285		5,655
Lease liability	9,105		9,235
Other	15,884		10,855
Gross deferred tax assets	692,227		602,435
Deferred tax liabilities
Business acquisition	(4,930)		(4,937)
Royalty payable	(105,453)		(68,209)
Convertible notes	—		(94)
Advanced R&D payments	(1,802)		(1,776)
Right of use asset	(3,130)		(3,420)
Total net deferred tax assets	576,912		523,999
Less: valuation allowance	(581,842)		(528,895)
Net deferred tax liability	$	(4,930)	$	(4,896)

Basic and Diluted Net Loss per Common Share (Tables)

12 Months Ended

Dec. 31, 2021

Earnings Per Share [Abstract]

Schedule of Reconciliation of the Numerator and Denominator Used in Computing 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:


	Years Ended December 31,
(in thousands, except per share amounts)	2021		2020		2019
Numerator:
Net loss attributable to common stockholders	$	(250,460)	$	(276,852)	$	(356,388)
Denominator:
Weighted average common shares outstanding — basic and diluted	271,421,986		258,867,380		240,421,001

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:


	Years ended December 31,
(in thousands)	2021	2020	2019
Options to purchase common stock	14,731	14,032	16,724
Unvested restricted stock units	7,341	7,080	5,792
Outstanding warrants, convertible to common stock	—	2,555	2,555
Convertible notes	—	462	462
Total number of potentially issuable shares	22,072	24,129	25,533

Description of Business (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended	12 Months Ended
	Sep. 30, 2021	Mar. 31, 2019	Jun. 30, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Stock issued from equity financing (in shares)			18,700,000
Proceeds from issuance of common stock from equity financing and pre-funded warrants, net of issuance costs	$ 199,800			$ 199,750	$ 0	$ 0
Accumulated deficit				$ 2,295,922	$ 2,045,462
Warrants
Debt Instrument [Line Items]
Stock issued from equity financing (in shares)		101,787
Private Placement
Debt Instrument [Line Items]
Stock issued (in dollars per share)	$ 10.18
Number of common shares called by warrants (in shares)	8,349,705
Private Placement \| Warrants
Debt Instrument [Line Items]
Stock issued (in dollars per share)	$ 10.17
Common Stock
Debt Instrument [Line Items]
Stock issued from equity financing (in shares)	11,296,660					18,720,930

- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

+ References + Details

Summary of Significant Accounting Policies - Concentration of Credit Risk (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Concentration Risk [Line Items]
Allowance for doubtful accounts receivable	$ 0.2
Net product sales \| Customer Concentration Risk \| Customer One
Concentration Risk [Line Items]
Concentration risk, percentage	24.00%	25.00%
Accounts receivable \| Customer Concentration Risk \| Customer One
Concentration Risk [Line Items]
Concentration risk, percentage	14.00%	12.00%

Summary of Significant Accounting Policies - Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2021
Minimum
Property and Equipment
Estimated useful lives	3 years
Maximum
Property and Equipment
Estimated useful lives	5 years

Summary of Significant Accounting Policies - Revenue by Geographical Area (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Net product sales	$ 305,514	$ 260,886	$ 182,237
U.S.
Disaggregation of Revenue [Line Items]
Net product sales	95,387	80,046	52,478
Ex-U.S.
Disaggregation of Revenue [Line Items]
Net product sales	$ 210,127	$ 180,840	$ 129,759

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8906-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 40
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9031-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9038-108599

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-Section 50
-Paragraph 32
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130543-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
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-Paragraph 22
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8736-108599

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e9054-108599

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130545-203045

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 924
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-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856

+ Details

Summary of Significant Accounting Policies - Equity Incentive Plan and Stock-Based Compensation (Details)	Dec. 31, 2021 plan
Equity-based Compensation
Number of equity-based employee compensation plans	1

Summary of Significant Accounting Policies - Segment Information and Recent Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2021 segment unit
Accounting Policies [Abstract]
Number of business segments \| segment	1
Number of reporting units \| unit	1

Goodwill and Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 197,797	$ 197,797	$ 197,800
In-process research & development	$ 23,000	$ 23,000	$ 23,000

Goodwill and Intangible Assets - Changes in IPR&D (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Changes in IPR&D
Beginning balance	$ 23,000	$ 23,000
Change in IPR&D	0	0
Ending balance	23,000	23,000
Changes in goodwill
Beginning balance	197,797	197,800
Change in goodwill	0	0
Ending balance	$ 197,797	$ 197,797

Cash, Cash Equivalents, Marketable Securities, and Restricted Cash - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Cash and cash equivalents	$ 245,197,000	$ 163,240,000	$ 142,837,000
Debt securities, available-for-sale	237,299,000	320,029,000
Debt securities, realized gain (loss)	0	0
Fair value of available-for-sale debt securities in unrealized loss positions	$ 173,400,000	$ 124,900,000

Cash, Cash Equivalents, Marketable Securities, and Restricted Cash - Cash and Available for Sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Cash and cash equivalents	$ 245,197	$ 163,240	$ 142,837
Fair value, cash balances	245,197	163,240
Cost, available-for-sale securities	237,371	320,016
Gross unrealized gain, available-for-sale securities	7	39
Gross unrealized loss, available-for-sale securities	(79)	(26)
Fair value, available-for-sale debt securities	237,299	320,029
Cost, cash balances and available-for-sale securities	482,568	483,256
Gross unrealized gain, cash balances and available-for-sale securities	7	39
Gross unrealized loss, cash balances and available-for-sale securities	(79)	(26)
Fair value, cash balances and available-for-sale securities	482,496	483,269
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Cost, available-for-sale securities	174,578	217,087
Gross unrealized gain, available-for-sale securities	7	14
Gross unrealized loss, available-for-sale securities	(54)	(6)
Fair value, available-for-sale debt securities	174,531	217,095
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities, cost	32,322	39,525
Corporate debt securities, gross unrealized gain	0	4
Corporate debt securities, gross unrealized loss	(11)	(16)
Corporate debt securities, fair value	32,311	39,513
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities, cost	30,070	9,420
Corporate debt securities, gross unrealized gain	0	18
Corporate debt securities, gross unrealized loss	(14)	0
Corporate debt securities, fair value	30,056	9,438
Money market
Debt Securities, Available-for-sale [Line Items]
Cost, available-for-sale securities	350	350
Gross unrealized gain, available-for-sale securities	0	0
Gross unrealized loss, available-for-sale securities	0	0
Fair value, available-for-sale debt securities	350	350
Certificate of deposit
Debt Securities, Available-for-sale [Line Items]
Cost, available-for-sale securities	51	51
Gross unrealized gain, available-for-sale securities	0	0
Gross unrealized loss, available-for-sale securities	0	0
Fair value, available-for-sale debt securities	$ 51	51
U.S. government agency bonds
Debt Securities, Available-for-sale [Line Items]
Corporate debt securities, cost		53,583
Corporate debt securities, gross unrealized gain		3
Corporate debt securities, gross unrealized loss		(4)
Corporate debt securities, fair value		$ 53,582

Cash, Cash Equivalents, Marketable Securities, and Restricted Cash - Reconciliation of Cash and Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Cash and cash equivalents	$ 245,197	$ 163,240	$ 142,837
Restricted cash	4,259	2,922	3,506
Cash, cash equivalents, and restricted cash shown in the Consolidated Statements of Cash Flows	$ 249,456	$ 166,162	$ 146,343	$ 82,375

Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Inventory Disclosure [Abstract]
Raw materials	$ 12,289	$ 5,547
Work-in-process	10,699	7,693
Finished goods	3,830	6,316
Total inventories	26,818	19,556
Reserve for inventory	$ 1,100	$ 100

Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property and Equipment
Property and equipment, gross	$ 62,378	$ 58,350
Less accumulated depreciation	(19,882)	(14,487)
Net property and equipment	42,496	43,863
Depreciation and amortization	5,700	8,400
Leasehold improvements
Property and Equipment
Property and equipment, gross	24,168	24,146
Research equipment
Property and Equipment
Property and equipment, gross	16,663	15,387
Construction in progress
Property and Equipment
Property and equipment, gross	8,229	5,870
Computer equipment
Property and Equipment
Property and equipment, gross	5,720	5,546
Land
Property and Equipment
Property and equipment, gross	3,190	3,190
Furniture and fixtures
Property and Equipment
Property and equipment, gross	3,163	2,880
Computer software
Property and Equipment
Property and equipment, gross	1,174	1,207
Vehicles
Property and Equipment
Property and equipment, gross	$ 71	$ 124

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Accounts payable and accrued expenses
Accrued compensation and benefits	$ 24,258	$ 23,025
Accrued contract manufacturing & contract research costs	20,361	19,617
Accrued sales rebates and discounts	15,989	12,079
Accrued Program Fees	13,294	16,599
Accrued professional fees	9,377	3,700
Accrued taxes	6,154	11,177
Accrued royalties	4,522	6,550
Other	4,198	4,094
Accrued expenses and other current liabilities	$ 98,153	$ 96,841

Stockholders' Equity - Common Stock and Warrants (Details)	1 Months Ended		3 Months Ended					12 Months Ended
	Sep. 30, 2021 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) $ / shares shares	Sep. 30, 2021 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) $ / shares shares	Sep. 30, 2019 USD ($) shares	Jun. 30, 2019 USD ($) $ / shares shares	Mar. 31, 2019 USD ($) $ / shares	Dec. 31, 2021 USD ($) vote $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) shares
Convertible Debt
Common stock, shares authorized (in shares) \| shares								500,000,000	500,000,000
Voting right for each share held, number \| vote								1
Stock issued from equity financing (in shares) \| shares						18,700,000
Gross cash proceeds from warrant exercises		$ 800,000		$ 19,200,000				$ 19,230,000	$ 0	$ 812,000
Equity component of the convertible notes								$ 2,661,000		215,476,000
Common stock, par value (in dollars per share) \| $ / shares								$ 0.01	$ 0.01
Net proceeds from the issuance of common stock after deducting underwriting discounts and commissions						$ 189,000,000		$ 0	$ 0	188,994,000
Contingent consideration, milestone payment							$ 9,000,000
Milestone payment, stock issued as consideration							771,804
Stock issued for contingent consideration										9,316,000
Proceeds from issuance of common stock from equity financing and pre-funded warrants, net of issuance costs	$ 199,800,000							$ 199,750,000	$ 0	$ 0
Convertible Notes
Convertible Debt
Common stock, par value (in dollars per share) \| $ / shares						$ 0.01
2016 Convertible Notes \| Convertible Notes
Convertible Debt
Debt conversion, converted instrument, amount			$ 2,800,000		$ 247,200,000
Underwritten Offering
Convertible Debt
Stock issued (in dollars per share) \| $ / shares						$ 10.75
Private Placement
Convertible Debt
Number of common shares called by warrants (in shares) \| shares	8,349,705		8,349,705
Stock issued (in dollars per share) \| $ / shares	$ 10.18		$ 10.18
Exercise price of warrants (in dollars per share) \| $ / shares	$ 0.01		$ 0.01
Stock Exercises at $7.98
Convertible Debt
Exercise price of warrants (in dollars per share) \| $ / shares				$ 7.98
Stock Exercises at $7.06
Convertible Debt
Exercise price of warrants (in dollars per share) \| $ / shares				$ 7.06
Common Stock
Convertible Debt
Stock issued from equity financing (in shares) \| shares	11,296,660									18,720,930
Equity component of the convertible notes (in shares) \| shares			472,356		44,000,000					43,995,139
Equity component of the convertible notes			$ 5,000		$ 440,000
Stock issued for contingent consideration							8,000
Additional Paid-In Capital
Convertible Debt
Equity component of the convertible notes			$ 2,656,000		$ 215,036,000
Stock issued for contingent consideration							$ 9,308,000
Additional Paid-In Capital \| Convertible Notes
Convertible Debt
Equity component of the convertible notes										$ 215,000,000
Common Stock
Convertible Debt
Exercise price of warrants (in dollars per share) \| $ / shares		$ 7.98					$ 7.98
Warrants
Convertible Debt
Stock issued from equity financing (in shares) \| shares		101,787
Warrants \| Private Placement
Convertible Debt
Stock issued (in dollars per share) \| $ / shares	$ 10.17		$ 10.17
Warrants \| Stock Exercises at $7.98
Convertible Debt
Stock issued from equity financing (in shares) \| shares				1,294,999
Warrants \| Stock Exercises at $7.06
Convertible Debt
Stock issued from equity financing (in shares) \| shares				1,260,000

Stockholders' Equity - Nonqualified Cash Plan and Equity Incentive Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Stockholders' Equity
Deferred compensation investment	$ 4.8	$ 4.1
Expiration period	10 years
Vesting percentage	100.00%
Maximum \| Options to purchase common stock
Stockholders' Equity
Number of shares reserved for issuance (in shares)	18,322,154
First Anniversary
Stockholders' Equity
Monthly vesting percentage	2.08%
Vesting percentage	25.00%

Share based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Dec. 21, 2018	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant-date fair value, options (in dollars per share)		$ 9.08	$ 6.40	$ 6.67
Aggregate intrinsic value of options exercised		$ 8,500	$ 40,900	$ 11,800
Proceeds from stock options exercised, net		10,228	$ 42,282	$ 11,476
Total unrecognized compensation costs		$ 28,900
Unvested restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period following separation for accelerated vesting	2 years
RSUs vested and non-vested units expected to vest (in shares)		1,863,436	2,164,000	921,000
Unrecognized compensation cost		$ 47,600
Unrecognized compensation costs, period for recognition (in years)		2 years
Options to purchase common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs, period for recognition (in years)		3 years

Share based Compensation - Weighted-average Assumptions (Details) - Options to purchase common stock - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected stock price volatility	65.40%	75.10%	74.10%
Risk free interest rate	0.60%	1.60%	2.40%
Expected life of options (years)	5 years 4 months 24 days	5 years 8 months 1 day	5 years 8 months 4 days
Expected annual dividend per share (in dollars per share)	$ 0.00	$ 0.00	$ 0.00

Share based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Number of Shares
Balance at the beginning of the period (in shares)	14,032,000	16,724,000	15,810,000
Options, Granted (in shares)	3,262,000	4,362,000	4,091,000
Options, Exercised (in shares)	(1,483,000)	(5,243,000)	(1,967,000)
Options, Forfeited (in shares)	(844,000)	(1,376,000)	(879,000)
Options, Expired (in shares)	(236,000)	(435,000)	(331,000)
Balance at the end of the period (in shares)	14,731,000	14,032,000	16,724,000
Vested and unvested expected to vest as of the end of the period (in shares)	13,432,000
Exercisable at the end of the period (in shares)	9,141,000
Weighted Average Exercise Price
Balance at the beginning of the period (in dollars per share)	$ 9.54	$ 9.15	$ 8.63
Options, Granted (in dollars per share)	16.53	9.98	10.29
Options, Exercised (in dollars per share)	7.05	8.11	5.83
Options, Forfeited (in dollars per share)	12.97	10.42	11.07
Options, Expired (in dollars per share)	13.28	13.33	13.38
Balance at the end of the period (in dollars per share)	11.08	$ 9.54	$ 9.15
Vested and unvested expected to vest as of the end of the period (in dollars per share)	10.89
Exercisable at the end of the period (in dollars per share)	$ 9.58
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Balance at the end of the period	6 years 4 months 24 days
Vested and unvested expected to vest at the end of the period	6 years 2 months 12 days
Exercisable at the end of the period	5 years 1 month 6 days
Aggregate intrinsic value of options outstanding	$ 30.3
Aggregate intrinsic value of options vested and unvested expected to vest	28.8
Aggregate intrinsic value of options exercisable	$ 24.5

Share based Compensation - RSUs and PBRSUs Summary (Details) - Unvested restricted stock units - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Number of Shares
Non-vested units as of the beginning of the period (in shares)	7,080,000	5,792,000	3,712,000
Granted (in shares)	3,191,000	4,692,000	3,526,000
Vested (in shares)	(1,863,436)	(2,164,000)	(921,000)
Forfeited (in shares)	(1,067,000)	(1,240,000)	(525,000)
Non-vested units as of the end of the period (in shares)	7,341,000	7,080,000	5,792,000
Weighted Average Grant Date Fair Value
Non-vested units as of the beginning of the period (in dollars per share)	$ 11.35	$ 11.18	$ 10.59
Granted (in dollars per share)	16.94	11.29	10.92
Vested (in dollars per share)	15.77	10.70	8.49
Forfeited (in dollars per share)	12.82	11.14	10.52
Non-vested units as of the end of the period (in dollars per share)	$ 13.90	$ 11.35	$ 11.18
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Non-vested units, weighted average remaining years	2 years 3 months 18 days
Non-vested units, aggregate intrinsic value	$ 84.8

Share based Compensation - Expense Summary (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total equity compensation expense	$ 57,838	$ 49,151	$ 44,430
Research and development expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total equity compensation expense	17,340	20,817	17,575
Selling, general, and administrative expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total equity compensation expense	$ 40,498	$ 28,334	$ 26,855

Assets and Liabilities Measured at Fair Value - Summary of Fair Value of Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Assets:
Fair value of assets	$ 242,048	$ 324,055
Liabilities:
Contingent consideration payable	20,339	25,825
Deferred compensation plan liability	4,800	4,078
Fair value of liabilities	25,139	29,903
Commercial paper
Assets:
Fair value of assets	174,531	217,095
Corporate debt securities
Assets:
Fair value of assets	32,311	39,513
Asset-backed securities
Assets:
Fair value of assets	30,056	9,438
Money market
Assets:
Fair value of assets	5,150	4,427
U.S. government agency bonds
Assets:
Fair value of assets		53,582
Level 2
Assets:
Fair value of assets	242,048	324,055
Liabilities:
Contingent consideration payable	0	0
Deferred compensation plan liability	4,800	4,078
Fair value of liabilities	4,800	4,078
Level 2 \| Commercial paper
Assets:
Fair value of assets	174,531	217,095
Level 2 \| Corporate debt securities
Assets:
Fair value of assets	32,311	39,513
Level 2 \| Asset-backed securities
Assets:
Fair value of assets	30,056	9,438
Level 2 \| Money market
Assets:
Fair value of assets	5,150	4,427
Level 2 \| U.S. government agency bonds
Assets:
Fair value of assets		53,582
Level 3
Liabilities:
Contingent consideration payable	20,339	25,825
Deferred compensation plan liability	0	0
Fair value of liabilities	$ 20,339	$ 25,825

Assets and Liabilities Measured at Fair Value - Narrative (Details)	3 Months Ended
	Mar. 31, 2019 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Financial assets and liabilities subject to fair value measurements
Contingent consideration payable		$ 20,339,000	$ 25,825,000
Milestone payment, stock issued as consideration	$ 771,804
Level 3
Financial assets and liabilities subject to fair value measurements
Contingent consideration payable		20,339,000	$ 25,825,000
Callidus \| Clinical and Regulatory Approval Milestones \| ATB-200 Pompe Program \| Probability weighted discounted cash flow
Financial assets and liabilities subject to fair value measurements
Contingent consideration payable		$ 18,883,000
Callidus \| Clinical and Regulatory Approval Milestones \| Probability of achievement of milestones \| ATB-200 Pompe Program \| Minimum
Financial assets and liabilities subject to fair value measurements
Contingent consideration, measurement input		0.75
Callidus \| Clinical and Regulatory Approval Milestones \| Probability of achievement of milestones \| ATB-200 Pompe Program \| Maximum
Financial assets and liabilities subject to fair value measurements
Contingent consideration, measurement input		0.88
Callidus \| Clinical and Regulatory Approval Milestones \| Level 3 \| Discount rate \| ATB-200 Pompe Program
Financial assets and liabilities subject to fair value measurements
Contingent consideration, measurement input		0.075

Assets and Liabilities Measured at Fair Value - Level 3 Roll Forward (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of the period	$ 25,825	$ 22,681
Changes in fair value during the period, included in the Consolidated Statements of Operations	6,514	3,144	$ 3,297
Payment of contingent consideration in cash	(12,000)	0
Balance, end of the period	$ 20,339	$ 25,825	$ 22,681

Debt - Summary of Long Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Debt Instruments
Net carrying value of Long-term debt	$ 389,357	$ 389,254
Convertible Notes \| Senior Secured Term Loan due 2026:
Debt Instruments
Principal	400,000	400,000
Less: debt discount	(6,074)	(7,434)
Less: deferred financing	(4,569)	(5,592)
Net carrying value of Long-term debt	389,357	386,974
Convertible Notes \| 2016 Convertible Notes
Debt Instruments
Principal	0	2,825
Less: debt discount	0	(518)
Less: deferred financing	0	(27)
Net carrying value of Long-term debt	$ 0	$ 2,280

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References + Details

Debt - Narrative (Details)	1 Months Ended		3 Months Ended		6 Months Ended	12 Months Ended
Debt - Narrative (Details)	Jul. 31, 2020 USD ($) day	Dec. 31, 2016 USD ($) $ / shares shares	Sep. 30, 2021 USD ($) shares	Sep. 30, 2019 USD ($) shares	Jun. 30, 2019 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) $ / shares	Dec. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($) shares	Sep. 30, 2018 USD ($)
Convertible Debt
Loss on extinguishment of debt						$ (257,000)	$ (7,276,000)	$ 0
Proceeds from long-term debt, net of issuance costs						$ 0	$ 385,929,000	0
Common stock, par value (in dollars per share) \| $ / shares						$ 0.01	$ 0.01
Equity component of the convertible notes						$ 2,661,000		215,476,000
Loss on exchange of convertible notes						0	$ 0	40,624,000
Proceeds from termination of capped call confirmations						$ 0	$ 0	$ 19,875,000
Additional Paid-In Capital
Convertible Debt
Equity component of the convertible notes			$ 2,656,000	$ 215,036,000
Common Stock
Convertible Debt
Equity component of the convertible notes			$ 5,000	$ 440,000
Equity component of the convertible notes (in shares) \| shares			472,356	44,000,000				43,995,139
Convertible Notes
Convertible Debt
Exchange agreement, aggregate principal amount					$ 247,200,000
Exchange agreement, authorized (in shares) \| shares					44,000,000
Common stock, par value (in dollars per share) \| $ / shares					$ 0.01
Accrued and unpaid interest on exchange agreement					$ 1,300,000
Gain (loss) on extinguishment of debt, fair value of common shares issued								$ 400,000
Loss on exchange of convertible notes								40,600,000
Proceeds from termination of capped call confirmations					$ 19,900,000
Convertible Notes \| Additional Paid-In Capital
Convertible Debt
Equity component of the convertible notes								$ 215,000,000
Convertible Notes \| 2016 Convertible Notes
Convertible Debt
Aggregate principal amount		$ 250,000,000
Proceeds from long-term debt, net of issuance costs		243,000,000
Proceeds for capped call confirmations		$ 13,500,000
Shares issued per increment of convertible debt (in shares) \| shares		40,800,000
Debt conversion ratio (in shares)		0.1633987
Conversion price (in dollars per share) \| $ / shares		$ 6.12
Debt conversion, converted instrument, amount			$ 2,800,000	$ 247,200,000
Convertible Notes \| 2016 Convertible Notes \| Private Placement Purchase Agreement \| Over-allotment Option
Convertible Debt
Aggregate principal amount		$ 25,000,000
Secured Debt \| Senior Secured Term Loan due 2026:
Convertible Debt
Interest expense, debt	$ 1,100,000
Early settlement premiums	5,200,000
Loss on extinguishment of debt	(7,300,000)
Secured Debt \| Senior Loans
Convertible Debt
Maximum borrowing capacity	$ 400,000,000
Number of payments \| day	9
Periodic payment	$ 44,400,000
Proceeds from secured lines of credit	385,900,000
Minimum liquidity covenant	75,000,000
Secured Debt \| Senior Loans \| Minimum
Convertible Debt
Consolidated revenue covenant, amount	140,000,000
Secured Debt \| Senior Loans \| Maximum
Convertible Debt
Consolidated revenue covenant, amount	$ 225,000,000
Secured Debt \| Senior Loans \| LIBOR
Convertible Debt
Variable rate	1.00%
Basis spread on variable rate	6.50%
Line of Credit
Convertible Debt
Maximum borrowing capacity									$ 150,000,000

Debt - Interest Expense (Details) - USD ($) $ in Thousands	12 Months Ended
Debt - Interest Expense (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Convertible Notes \| 2016 Convertible Notes
Interest expense
Contractual interest expense	$ 30,473	$ 20,933
Amortization of debt discount	1,462	1,267
Amortization of deferred financing	$ 1,028	$ 527
Effective interest rate of the liability component	0.00%	10.60%
Senior Notes \| Senior Secured Term Loan due 2026:
Interest expense
Effective interest rate of the liability component	8.40%	8.40%

Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease cost	$ 10,000	$ 11,100
Variable lease cost	2,100	1,800
Cash paid for amounts included in operating lease liabilities	8,400	9,600
Right-of-use assets obtained in exchange for new operating lease liabilities	300	1,700
Tenant improvements paid through lease incentive	300	470	$ 19,388
Operating lease ROU assets, net	20,586	23,296
Current portion of the operating lease liabilities	7,409	6,872
Non-current portion of the operating lease liabilities	43,363	45,604
Total operating lease liability	$ 50,772	$ 52,476
Weighted-average remaining lease terms (years)	19 years 7 months 6 days	19 years 9 months 18 days
Weighted-average discount rate	13.10%	13.00%
Operating Lease
2022	$ 8,514
2023	8,622
2024	8,347
2025	8,304
2026	8,454
Thereafter	145,948
Total lease payments	188,189
Less lease incentives	(28,939)
Less imputed interest	(108,478)
Total operating lease liability	50,772	$ 52,476
Lease not yet commenced, liability	$ 15,100
Lease not yet commenced, term of contract	10 years

Income Taxes - Statutory Rate (Details) - USD ($)		12 Months Ended
Income Taxes - Statutory Rate (Details) - USD ($)	Dec. 22, 2017	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income (loss) before income taxes:
United States		$ (333,571,000)	$ (365,332,000)	$ (393,955,000)
Foreign		92,017,000	91,078,000	38,045,000
Loss before income tax		(241,554,000)	(274,254,000)	(355,910,000)
Current
Federal		0	0	0
State		0	0	0
Foreign		8,857,000	4,163,000	2,877,000
Deferred
Federal		15,000	(1,410,000)	(984,000)
State		34,000	(155,000)	(1,415,000)
Foreign		0	0	0
Income tax expense (benefit)		$ 8,906,000	$ 2,598,000	$ 478,000
Reconciliation of the statutory tax rates and the effective tax rates
Statutory rate	(21.00%)	(21.00%)	(21.00%)	(21.00%)
State taxes, net of federal benefit		0.00%	0.00%	0.00%
Nondeductible IPR&D		0.00%	0.00%	0.00%
Contingent consideration		0.00%	0.00%	0.00%
Tax credits		(9.00%)	(7.00%)	(16.00%)
Impact of foreign operations		3.00%	4.00%	9.00%
Nondeductible executive compensation		2.00%	2.00%	1.00%
Nondeductible debt conversion		0.00%	0.00%	(1.00%)
Other		1.00%	0.00%	(1.00%)
Valuation allowance		28.00%	23.00%	29.00%
Net		4.00%	1.00%	0.00%
Accrual for interest and penalties		$ 0

Income Taxes - Deferred and Valuation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets
Intellectual property	$ 105,453	$ 68,209
Amortization/depreciation	277	489
Research tax credit	205,095	182,651
Net operating loss carry forwards	334,762	305,876
Deferred reimbursements	1,587	1,912
Non-cash stock issue	11,779	17,553
Interest carry forward limitation	8,285	5,655
Lease liability	9,105	9,235
Other	15,884	10,855
Gross deferred tax assets	692,227	602,435
Deferred tax liabilities
Business acquisition	(4,930)	(4,937)
Royalty payable	(105,453)	(68,209)
Convertible notes	0	(94)
Advanced R&D payments	(1,802)	(1,776)
Right of use asset	(3,130)	(3,420)
Total net deferred tax assets	576,912	523,999
Less: valuation allowance	(581,842)	(528,895)
Net deferred tax liability	(4,930)	$ (4,896)
Increase in the valuation allowance	$ (52,900)

Income Taxes - Loss Carryforwards (Details) $ in Millions	Dec. 31, 2021 USD ($)
Research and experimentation tax credit carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward amount	$ 30.3
Orphan drug tax credit carryforwards
Operating Loss Carryforwards [Line Items]
Tax credit carryforward amount	165.2
Federal
Operating Loss Carryforwards [Line Items]
Amount of net operating loss carry forwards	1,292.0
State
Operating Loss Carryforwards [Line Items]
Amount of net operating loss carry forwards	$ 1,000.0

Collaborative Agreements (Details) $ in Thousands	1 Months Ended		12 Months Ended
Collaborative Agreements (Details) $ in Thousands	Oct. 31, 2018 USD ($)	Nov. 30, 2013 USD ($) market	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Collaborative Agreements
Net product sales			$ 305,514	$ 260,886	$ 182,237
Deferred reimbursements			5,906	7,406
Accrued expenses and other current liabilities			98,153	$ 96,841
Collaborative Arrangements
Collaborative Agreements
Conditional aggregate payments per indication	$ 88,000
Discovery program fee	$ 10,000
Term of agreement	5 years
Collaborative Arrangements \| GSK
Collaborative Agreements
Payments for collaborative agreement			1,500
Revised Agreement \| GSK
Collaborative Agreements
Potential milestone payments upon achievement of post-approval and sales-based milestones		$ 40,000
Number of major markets outside the U.S. from whom parties to contractual arrangement is eligible to receive post-approval and sales-based milestones \| market		8
Net product sales			25,400
Deferred reimbursements			7,400
Accrued expenses and other current liabilities			$ 4,500

Basic and Diluted Net Loss per Common Share (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Numerator:
Net loss attributable to common stockholders	$ (250,460)	$ (276,852)	$ (356,388)
Denominator:
Weighted-average common shares outstanding - basic (in shares)	271,421,986	258,867,380	240,421,001
Weighted-average common shares outstanding - diluted (in shares)	271,421,986	258,867,380	240,421,001
Antidilutive securities
Antidilutive securities excluded from computation of diluted earnings per share (in shares)	22,072,000	24,129,000	25,533,000
Options to purchase common stock
Antidilutive securities
Antidilutive securities excluded from computation of diluted earnings per share (in shares)	14,731,000	14,032,000	16,724,000
Unvested restricted stock units
Antidilutive securities
Antidilutive securities excluded from computation of diluted earnings per share (in shares)	7,341,000	7,080,000	5,792,000
Outstanding warrants, convertible to common stock
Antidilutive securities
Antidilutive securities excluded from computation of diluted earnings per share (in shares)	0	2,555,000	2,555,000
Convertible notes
Antidilutive securities
Antidilutive securities excluded from computation of diluted earnings per share (in shares)	0	462,000	462,000