ACADIA Pharmaceuticals (ACAD) 10-K 27 Feb 20 2019 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2019	Jan. 31, 2020	Jun. 28, 2019
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Trading Symbol	ACAD
Entity Registrant Name	ACADIA PHARMACEUTICALS INC
Entity Central Index Key	0001070494
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		155,339,667
Entity Public Float			$ 2,200,000,000
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Entity File Number	000-50768
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	06-1376651
Entity Address, Address Line One	3611 Valley Centre Drive
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92130
City Area Code	858
Local Phone Number	558-2871
Document Transition Report	false
Document Annual Report	true
Documents Incorporated by Reference	Portions of the registrant’s definitive Proxy Statement to be filed with the Securities and Exchange Commission by April 29, 2020 are incorporated by reference into Part III of this report.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Assets
Cash and cash equivalents	$ 189,680,000	$ 134,758,000
Investment securities, available-for-sale	507,749,000	338,762,000
Accounts receivable, net	35,781,000	26,090,000
Interest and other receivables	2,093,000	1,699,000
Inventory	6,341,000	4,070,000
Prepaid expenses	18,606,000	20,727,000
Total current assets	760,250,000	526,106,000
Property and equipment, net	3,180,000	3,309,000
Operating lease right-of-use assets	9,524,000	0
Intangible assets, net	2,585,000	4,062,000
Restricted cash	4,787,000	4,826,000
Other assets	2,857,000	1,899,000
Total assets	783,183,000	540,202,000
Liabilities and stockholders’ equity
Accounts payable	7,222,000	3,167,000
Accrued liabilities	67,604,000	56,398,000
Total current liabilities	74,826,000	59,565,000
Operating lease liabilities	6,361,000
Other long-term liabilities	2,861,000	1,558,000
Total liabilities	84,048,000	61,123,000
Commitments and contingencies (Note 9)
Stockholders’ equity:
Preferred stock, $0.0001 par value; 5,000,000 shares authorized at December 31, 2019 and 2018; no shares issued and outstanding at December 31, 2019 and 2018
Common stock, $0.0001 par value; 225,000,000 shares authorized at December 31, 2019 and 2018; 155,275,300 shares and 143,853,597 shares issued and outstanding at December 31, 2019 and 2018, respectively	15,000	14,000
Additional paid-in capital	2,402,945,000	1,948,300,000
Accumulated deficit	(1,704,122,000)	(1,468,863,000)
Accumulated other comprehensive income (loss)	297,000	(372,000)
Total stockholders’ equity	699,135,000	479,079,000
Total liabilities and stockholders’ equity	$ 783,183,000	$ 540,202,000

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	225,000,000	225,000,000
Common stock, shares issued	155,275,300	143,853,597
Common stock, shares outstanding	155,275,300	143,853,597

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Revenues
Revenue, Product and Service [Extensible List]	us-gaap:ProductMember		us-gaap:ProductMember		us-gaap:ProductMember
Total revenues	$ 339,076		$ 223,807		$ 124,901
Operating expenses
Cost, Product and Service [Extensible List]	us-gaap:ProductMember		us-gaap:ProductMember		us-gaap:ProductMember
Cost of product sales	$ 11,344		$ 12,377		$ 9,077
License fees and royalties	8,254		5,953		3,983
Research and development	240,385		187,163		149,189
Selling, general and administrative	325,638		265,758		255,062
Total operating expenses	585,621		471,251		417,311
Loss from operations	(246,545)		(247,444)		(292,410)
Interest income, net	11,165		5,348		4,126
Other income (expense)	997		(1,840)
Loss before income taxes	(234,383)		(243,936)		(288,284)
Income tax expense	876		1,256		1,119
Net loss	$ (235,259)		$ (245,192)		$ (289,403)
Net loss per common share, basic and diluted	$ (1.60)	[1]	$ (1.94)	[1]	$ (2.36)
Weighted average common shares outstanding, basic and diluted	147,199		126,583		122,600
[1]	Net loss per common share, basic and diluted, are computed independently for each quarter and the full year based upon respective average shares outstanding. Therefore, the sum of the quarterly net loss per common share amounts may not equal the annual amounts reported.

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (235,259)	$ (245,192)	$ (289,403)
Other comprehensive income (loss):
Unrealized gain (loss) on investment securities	667	24	(499)
Foreign currency translation adjustments	2	3	(6)
Comprehensive loss	$ (234,590)	$ (245,165)	$ (289,908)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities
Net loss	$ (235,259)	$ (245,192)	$ (289,403)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	82,265	81,564	75,532
Amortization of premiums and accretion of discounts on investment securities	(3,613)	(578)	(291)
Amortization of intangible assets	1,477	1,476	1,477
(Gain) loss on strategic investment	(997)	1,840
Depreciation	1,289	1,529	1,236
Loss on disposal of assets	3	88	4
Changes in operating assets and liabilities:
Accounts receivable, net	(9,691)	(8,747)	(11,440)
Interest and other receivables	(394)	(612)	150
Inventory	(1,737)	1,926	(1,012)
Prepaid expenses and other current assets	2,121	(12,270)	(911)
Operating lease right-of-use assets	3,875
Other assets	39	(236)	431
Accounts payable	4,055	(5,619)	4,874
Accrued liabilities	6,458	15,994	4,206
Deferred revenue			(2,644)
Operating lease liabilities	(2,518)
Long-term liabilities	1,497	1,367	34
Net cash used in operating activities	(151,130)	(167,470)	(217,757)
Cash flows from investing activities
Purchases of investment securities	(578,634)	(327,914)	(478,818)
Maturities of investment securities	413,927	261,678	572,103
Purchases of strategic investments		(3,149)
Proceeds from sale of property and equipment		44
Purchases of property and equipment	(1,129)	(2,148)	(812)
Net cash (used in) provided by investing activities	(165,836)	(71,489)	92,473
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs	371,847	306,647	31,188
Net cash provided by financing activities	371,847	306,647	31,188
Effect of exchange rate changes on cash	2	3	(6)
Net increase (decrease) in cash, cash equivalents and restricted cash	54,883	67,691	(94,102)
Cash, cash equivalents and restricted cash
Beginning of period	139,584	71,893	165,995
End of period	194,467	139,584	71,893
Supplemental disclosure of cash flow information:
Cash paid for income taxes	1,597	1,261	1,367
Supplemental disclosure of noncash information:
Property and equipment purchases in accounts payable and accrued liabilities	$ 34	$ 160	$ 9

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2016	$ 518,411	$ 12	$ 1,452,272	$ (933,979)	$ 106
Beginning balance (in shares) at Dec. 31, 2016		121,367,169
Issuance of common stock from exercise of stock options	26,665		26,665
Issuance of common stock from exercise of stock options (in shares)		1,442,411
Issuance of common stock pursuant to employee stock purchase plan	4,522		4,522
Issuance of common stock pursuant to employee stock purchase plan (in shares)		192,402
Issuance of common stock from exercise of warrants on a net issuance basis (in shares)		1,408,570
Net loss	(289,403)			(289,403)
Cumulative effect adjustment from adoption of ASU 2016-09	(289)			(289)
Stock-based compensation	75,884		75,884
Other comprehensive income (loss)	(505)				(505)
Ending balance at Dec. 31, 2017	335,285	$ 12	1,559,343	(1,223,671)	(399)
Beginning balance (in shares) at Dec. 31, 2017		124,410,552
Issuance of common stock in public offering, net of issuance costs	298,537	$ 2	298,535
Issuance of common stock in public offering, net of issuance costs (in shares)		18,602,941
Issuance of common stock from exercise of stock options and units	4,428		4,428
Issuance of common stock from exercise of stock options and units (in shares)		599,529
Issuance of common stock pursuant to employee stock purchase plan	3,682		3,682
Issuance of common stock pursuant to employee stock purchase plan (in shares)		233,720
Issuance of common stock from exercise of warrants on a net issuance basis (in shares)		6,855
Net loss	(245,192)			(245,192)
Stock-based compensation	82,312		82,312
Other comprehensive income (loss)	27				27
Ending balance at Dec. 31, 2018	479,079	$ 14	1,948,300	(1,468,863)	(372)
Beginning balance (in shares) at Dec. 31, 2018		143,853,597
Issuance of common stock in public offering, net of issuance costs	$ 271,452	$ 1	271,451
Issuance of common stock in public offering, net of issuance costs (in shares)		7,187,500
Issuance of common stock from exercise of stock options (in shares)	3,880,757
Issuance of common stock from exercise of stock options and units	$ 95,984		95,984
Issuance of common stock from exercise of stock options and units (in shares)		3,965,166
Issuance of common stock pursuant to employee stock purchase plan	4,411		4,411
Issuance of common stock pursuant to employee stock purchase plan (in shares)		269,037
Net loss	(235,259)			(235,259)
Stock-based compensation	82,799		82,799
Other comprehensive income (loss)	669				669
Ending balance at Dec. 31, 2019	$ 699,135	$ 15	$ 2,402,945	$ (1,704,122)	$ 297
Beginning balance (in shares) at Dec. 31, 2019		155,275,300

Organization and Business

Organization and Business	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Organization and Business	1. Organization and Business ACADIA Pharmaceuticals Inc. (the “Company”), based in San Diego, California, is a biopharmaceutical company focused on the development and commercialization of innovative medicines to address unmet medical needs in central nervous system disorders. The Company was originally incorporated in Vermont in 1993 as Receptor Technologies, Inc. and reincorporated in Delaware in 1997. In April 2016, the U.S. Food and Drug Administration (“FDA”) approved the Company’s first drug, NUPLAZID ®

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Significant accounting policies followed in the preparation of these financial statements are as follows: Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries located in Europe. All intercompany accounts and transactions have been eliminated in consolidation. Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates. Cash and Cash Equivalents The Company considers all highly liquid investments with a maturity date at the date of purchase of three months or less to be cash equivalents. The following table provides a reconciliation of cash, cash equivalents and restricted cash reported in the consolidated balance sheets that sum to the total of the same such amounts shown in the Consolidated Statements of Cash Flows (in thousands). Twelve Months Ended December 31, 2019 Twelve Months Ended December 31, 2018 Beginning of period End of period Beginning of period End of period Cash and cash equivalents $ 134,758 $ 189,680 $ 69,418 $ 134,758 Restricted cash 4,826 4,787 2,475 4,826 Total cash, cash equivalents and restricted cash shown in the statements of cash flows $ 139,584 $ 194,467 $ 71,893 $ 139,584 Investment Securities The Company has classified all of its investment securities as available-for-sale as the sale of such securities may be required prior to maturity to implement management strategies, and accordingly, carries these investments at fair value. Unrealized gains and losses, if any, are reported as a separate component of stockholders’ equity. The cost of investment securities classified as available-for-sale is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion are included in interest income. Realized gains and losses, if any, are also included in interest income. The cost of securities sold is based on the specific identification method. Fair Value of Financial Instruments The carrying values of the Company’s financial instruments, consisting of cash and cash equivalents, trade receivables, interest and other receivables, restricted cash, and accounts payable and accrued liabilities, approximate fair value due to the relative short-term nature of these instruments. As disclosed in Note 4, the Company classifies its cash equivalents and available-for-sale investment securities within the fair value hierarchy as defined by authoritative guidance: Level 1 Inputs — Quoted prices for identical instruments in active markets. Level 2 Inputs — Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations in which all significant inputs and significant value drivers are observable. Level 3 Inputs — Valuation derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable. Accounts Receivable Accounts receivable are recorded net of customer allowances for distribution fees, prompt payment discounts, chargebacks, and doubtful accounts. Allowances for distribution fees, prompt payment discounts and chargebacks are based on contractual terms. The Company estimates the allowance for doubtful accounts based on existing contractual payment terms, actual payment patterns of its customers and individual customer circumstances. At December 31, 2019, the Company determined that an allowance for doubtful accounts was not required. No accounts were written off during the year ended December 31, 2019. During the year ended December 31, 2018, the Company wrote off less than $0.1 million. Inventory Inventory is stated at the lower of cost or net realizable value under the first-in, first-out method, or FIFO. The Company uses a combination of standard and actual costing methodologies to determine the cost basis for its inventories which approximates actual costs. Inventory consists of raw material, work in process, and finished goods, including third-party manufacturing costs, freight, and indirect overhead costs. The Company capitalizes inventory costs associated with its products upon regulatory approval when, based on management’s judgment, future commercialization is considered probable and the future economic benefit is expected to be realized; otherwise, such costs are expensed. Prior to FDA approval of NUPLAZID in April 2016, all costs related to the manufacturing of NUPLAZID were charged to research and development expense in the period incurred. The Company periodically reviews inventory and reduces the carrying value of items to net realizable value for potentially excess, dated or obsolete inventory based on an analysis of forecasted demand compared to quantities on hand and any firm purchase orders, as well as product shelf life. During the years ended December 31, 2019, 2018 and 2017, the Company recorded charges of $1.1 million, $2.7 million and $0.7 million, respectively, to reduce certain finished goods and work in process inventory to its net realizable value. Property and Equipment Property and equipment are recorded at cost and depreciated over their estimated useful lives using the straight-line method. Leasehold improvements are amortized over the shorter of their estimated useful lives or the term of the lease by use of the straight-line method. Construction-in-process reflects amounts incurred for property, equipment or improvements that have not been placed in service. Maintenance and repair costs are expensed as incurred. When assets are retired or sold, the assets and accumulated depreciation are removed from the respective accounts and any gain or loss is recognized. Estimated useful lives by major asset category are as follows: Useful Lives Machinery and equipment 5 to 7 years Computers and software 3 years Furniture and fixtures 10 years Impairment of Long-Lived Assets The Company reviews its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability is measured by a comparison of the carrying amount of an asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized by the amount by which the carrying amount of the asset exceeds the fair value of the asset. Through December 31, 2019, no such impairment losses have been recorded by the Company. License Fees and Royalties The Company expenses amounts paid to acquire licenses associated with products under development when the ultimate recoverability of the amounts paid is uncertain and the technology has no alternative future use when acquired. Acquisitions of technology licenses are charged to expense or capitalized based upon management’s assessment regarding the ultimate recoverability of the amounts paid and the potential for alternative future use. The Company has determined that technological feasibility for its product candidates is reached when the requisite regulatory approvals are obtained to make the product available for sale. In connection with the FDA approval of NUPLAZID in April 2016, the Company made a one-time milestone payment of $8.0 million pursuant to its 2006 license agreement with the Ipsen Group in which the Company licensed certain intellectual property rights that complement its patent portfolio for its serotonin platform, including NUPLAZID. The Company capitalized the $8.0 million payment as an intangible asset and is amortizing the asset on a straight-line basis over the estimated useful life of the licensed patents through the second half of 2021. The Company recorded amortization expense related to its intangible asset of $1.5 million for each of the years ended December 31, 2019, 2018 and 2017. As of December 31, 2019, estimated future amortization expense related to the Company’s intangible asset was $1.5 million for 2020, and $1.0 million for 2021. Royalties incurred in connection with the Company’s license agreement with the Ipsen Group, as disclosed in Note 9, are expensed to license fees and royalties as revenue from product sales is recognized. Advertising Expense In connection with the FDA approval and commercial launch of NUPLAZID in 2016, the Company began to incur advertising costs. Advertising costs are expensed when services are performed or goods are delivered. The Company incurred $38.3 million, $39.8 million and $15.6 million in advertising costs during the years ended December 31, 2019, 2018 and 2017, respectively, related to its marketed product, NUPLAZID. No advertising costs were capitalized as prepaid expenses at December 31, 2019 or 2018. Revenue Recognition Product Sales, Net Effective January 1, 2018, the Company adopted ASU 2014-09, Revenue from Contracts with Customers (Topic 606), No cumulative effect adjustment to the opening balance of retained earnings was necessary upon adoption, and there is no reconciliation of the Company’s Consolidated Statements of Operations, as no revenue recognition differences were identified when comparing the revenue recognition criteria under Topic 606 to previous requirements The Company’s net product sales consist of U.S. sales of NUPLAZID. NUPLAZID was approved by the FDA in April 2016 and the Company commenced shipments of NUPLAZID to specialty pharmacies (“SPs”) and specialty distributors (“SDs”) in late May 2016. SPs dispense product to a patient based on the fulfillment of a prescription and SDs sell product to government facilities, long-term care pharmacies, or in-patient hospital pharmacies. Product shipping and handling costs are included in cost of product sales. The Company recognizes revenue from product sales at the net sales price (the “transaction price”) which includes estimates of variable consideration for which reserves are established and reflects each of these as either a reduction to the related account receivable or as an accrued liability, depending on how the amount payable is settled. Overall, these reserves reflect the Company’s best estimates of the amount of consideration to which the Company is entitled based on the terms of the contract. The amount of variable consideration that is included in the transaction price may be constrained, and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from estimates, the Company may need to adjust its estimates, which would affect net revenue in the period of adjustment Distribution Fees : Distribution fees include distribution service fees paid to the SPs and SDs based on a contractually fixed percentage of the wholesale acquisition cost (“WAC”), fees for data, and prompt payment discounts. Distribution fees are recorded as an offset to revenue based on contractual terms at the time revenue from the sale is recognized . Rebates : Allowances for rebates include mandated discounts under the Medicaid Drug Rebate Program and the Medicare Part D prescription drug benefit. Rebates are amounts owed after the final dispensing of the product to a benefit plan participant and are based upon contractual agreements with, or statutory requirements pertaining to, Medicaid and Medicare benefit providers. The allowance for rebates is based on statutory discount rates, estimated payor mix, and expected utilization. The Company’s estimates for expected utilization of rebates are based on historical data received from the SPs and SDs since product launch. Rebates are generally invoiced and paid in arrears so that the accrual balance consists of an estimate of the amount expected to be incurred for the current quarter’s activity, plus an accrual balance for prior quarters’ unpaid rebates . Chargebacks : Chargebacks are discounts and fees that relate to contracts with government and other entities purchasing from the SDs at a discounted price. The SDs charge back to the Company the difference between the price initially paid by the SDs and the discounted price paid to the SDs by these entities. The Company also incurs group purchasing organization fees for transactions through certain purchasing organizations. The Company estimates sales with these entities and accrues for anticipated chargebacks and organization fees, based on the applicable contractual terms . Co-Payment Assistance : The Company offers co-payment assistance to commercially insured patients meeting certain eligibility requirements. Co-payment assistance is accrued for based on actual program participation and estimates of program redemption using data provided by third-party administrators . Product Returns : Consistent with industry practice, the Company offers the SPs and SDs limited product return rights for damages, shipment errors, and expiring product; provided that the return is within a specified period around the product expiration date as set forth in the applicable individual distribution agreement. The Company does not allow product returns for product that has been dispensed to a patient. As the Company receives inventory reports from the SPs and SDs and has the ability to control the amount of product that is sold to the SPs and SDs, it is able to make a reasonable estimate of future potential product returns based on this on-hand channel inventory data and sell-through data obtained from the SPs and SDs. In arriving at its estimate for product returns, the Company also considers historical product returns, the underlying product demand, and industry data specific to the specialty pharmaceutical distribution industry . Research and Development Expenses Research and development expenses are charged to operations as incurred. Research and development expenses include costs associated with services provided by contract organizations for preclinical development, pre-commercialization manufacturing expenses, and clinical trials, salaries and related personnel expenses including stock-based compensation expense, and facilities and equipment expenses. The Company accrues for costs incurred as the services are being provided by monitoring the status of the trial or services provided and the invoices received from its external service providers. When the Company makes payments in advance of services being provided, we record those amounts as prepaid expenses on our consolidated balance sheet and expense them as the services are rendered. Concentration Risk Financial instruments, which potentially subject the Company to concentrations of credit risk, principally consist of cash, cash equivalents, investment securities, accounts receivable, and restricted cash. The Company invests its excess cash primarily in money market funds, U.S. treasury notes, and high quality, marketable debt instruments of corporations and government sponsored enterprises in accordance with the Company’s investment policy. The Company’s investment policy defines allowable investments and establishes guidelines relating to credit quality, diversification, and maturities of its investments to preserve principal and maintain liquidity. All investment securities have a credit rating of at least A3/A- or better, or P-1/A-1 or better, as determined by Moody’s Investors Service or Standard & Poor’s. Further, the Company specifies credit quality standards for its customers that are designed to limit the Company’s credit exposure to any single party. The Company does not currently have any of its own manufacturing facilities, and therefore it depends on an outsourced manufacturing strategy for the production of NUPLAZID for commercial use and for the production of its product candidates for clinical trials. The Company has contracts in place with two third-party manufacturers of commercial drug product and one third-party manufacturer of drug substance that is approved for the production of NUPLAZID active pharmaceutical ingredient (“API”). Although there are potential sources of supply other than the Company’s existing suppliers, any new supplier would be required to qualify under applicable regulatory requirements. The Company has entered into distribution agreements with a limited number of SPs and SDs, and all of the Company’s product sales are to these customers. For the year ended December 31, 2019, the Company’s four largest customers represented approximately 77% of the Company’s product revenue and 75% of the Company’s accounts receivable balance at December 31, 2019. For the year ended December 31, 2018, the Company’s four largest customers represented approximately 85% of the Company’s product revenue and 84% of the Company’s accounts receivable balance at December 31, 2018. For the year ended December 31, 2017, the Company’s four largest customers represented approximately 89% of the Company’s product revenue and 87% of the Company’s accounts receivable balance at December 31, 2017. Stock-Based Compensation The fair value of each employee stock option and each employee stock purchase right granted is estimated on the grant date under the fair value method using the Black-Scholes valuation model. The estimated fair value of each stock option and purchase right is then expensed over the requisite service period, which is generally the vesting period. The following weighted-average assumptions were used during these periods: Years Ended December 31, 2019 2018 2017 Stock Options: Expected volatility 62 % 71 % 68 % Risk-free interest rate 2 % 3 % 2 % Expected dividend yield 0 % 0 % 0 % Expected life of options in years 5.7 5.7 5.8 Years Ended December 31, 2019 2018 2017 Employee Stock Purchase Plan: Expected volatility 62%-86% 59%-79% 44%-62% Risk-free interest rate 1.5%-2.4% 2.1%-2.8% 1.0%-1.7% Expected dividend yield 0 % 0 % 0 % Expected life in years 0.5-2.0 0.5-2.0 0.5-2.0 Expected Volatility. The Company considers its historical volatility and implied volatility when determining the expected volatility. Risk-Free Interest Rate. The Company determines its risk-free interest rate assumption based on the U.S. Treasury yield for obligations with contractual terms similar to the expected term of the stock option or purchase right being valued. Expected Dividend Yield. The Company has never paid any dividends and currently has no plans to do so. Expected Life. In determining the expected life for stock options, the Company considers, among other factors, its historical exercise experience to date as well as the mean time remaining to full vesting of all outstanding options and the mean time remaining to the end of the contractual term of all outstanding options. The estimated life for the Company’s employee stock purchase rights is based upon the terms of each offering period. The fair value of restricted stock units (“RSUs”) is estimated based on the closing market price of the Company’s common stock on the date of grant. RSUs generally vest annually over a four-year period. The table below summarizes the total stock-based compensation expense included in the Company’s statements of operations for the periods presented (in thousands): Years Ended December 31, 2019 2018 2017 Cost of product sales $ 2,936 $ 3,863 $ 3,690 Research and development 32,533 32,038 26,485 Sales, general and administrative 46,796 45,663 45,357 $ 82,265 $ 81,564 $ 75,532 Income Taxes Current income tax expense or benefit represents the amount of income taxes expected to be payable or refundable for the current year. A deferred income tax asset or liability is computed for the expected future impact of differences between the financial reporting and income tax bases of assets and liabilities and for the expected future tax benefit to be derived from tax credits and loss carryforwards. Deferred income tax expense or benefit represents the net change during the year in the deferred income tax asset or liability. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized. The Company recognizes the impact of a tax position in the financial statements only if that position is more likely than not of being sustained upon examination by taxing authorities, based on the technical merits of the position. Any interest and penalties related to uncertain tax positions will be reflected in income tax expense. Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted average number of common shares outstanding for the period, without consideration for common stock equivalents. Diluted net loss per share is computed by dividing the net loss by the weighted average number of common shares and common stock equivalents outstanding for the period determined using the treasury stock method. For purposes of this calculation, stock options, employee stock purchase rights, RSUs, and warrants are considered to be common stock equivalents but are not included in the calculations of diluted net loss per share for the periods presented as their effect would be antidilutive. The Company incurred net losses for all periods presented and there were no reconciling items for potentially dilutive securities. More specifically, at December 31, 2019, 2018 and 2017, options, employee stock purchase rights, RSUs, and warrants totaling approximately 19,516,000 shares, 20,824,000 shares and 18,526,000 shares, respectively, were excluded from the calculation of diluted net loss per share as their effect would have been anti-dilutive. Segment Reporting Management has determined that the Company operates in one business segment which is the development and commercialization of innovative medicines. All revenues for the years ended December 31, 2019, 2018 and 2017 were generated in the United States. Recently Issued Accounting Standards In December 2017, the Tax Cuts and Jobs Act (the “2017 Tax Act”) was enacted. The 2017 Tax Act includes a number of changes to existing U.S. tax laws that impact the company, most notably a reduction of the U.S. corporate income tax rate from 35 percent to 21 percent for tax years beginning after December 31, 2017. The 2017 Tax Act also provides for a one-time transition tax on certain foreign earnings and the acceleration of depreciation for certain assets placed into service after September 27, 2017 as well as prospective changes beginning in 2018, including repeal of the domestic manufacturing deduction, acceleration of tax revenue recognition, global intangible low taxed income, foreign derived intangible income deduction, additional limitations on executive compensation and limitations on the deductibility of interest. The Company recognized the income tax effects of the 2017 Tax Act in its 2017 financial statements in accordance with Staff Accounting Bulletin No. 118, which provides SEC staff guidance for the application of ASC Topic 740, Income Taxes In November 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-18, Statement of Cash Flows: Restricted Cash This guidance was effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. The Company adopted this guidance on January 1, 2018, using a retrospective transition method. The adoption of this ASU impacted the presentation of cash flows, with inclusion of restricted cash flows for each of the presented periods In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments , which changes the impairment model for most financial assets and certain other instruments. For trade receivables and other instruments, entities will be required to use a new forward-looking expected loss model that generally will result in the earlier recognition of allowances for losses. For available-for-sale debt securities with unrealized losses, the losses will be recognized as allowances rather than as reductions in the amortized cost of the securities. This guidance is effective for annual reporting periods beginning after December 15, 2019, including interim periods within those years, with early adoption permitted only as of annual reporting periods beginning after December 15, 2018. The Company adopt ed this guidance on January 1, 2020. The adoption of ASU 2016-13 did not have material impact on the Company’s consolidated financial statements. In April 2019 , the FASB issued ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments—Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments , which, among other things, provides entities with practical expedients and policy elections related to the presentation and disclosure of accrued interest and the related allowance for credit losses and clarifies how to disclose line-of-credit arrangements that are converted to term loans in the vintage table disclosure. ASU 2019-04 has the same effective date as the new credit impairment standard for entities that have not yet adopted the standard. For entities that early adopted the new credit impairment standard, ASU 2019-04 is effective for fiscal years beginning after December 15, 2019 and interim periods therein. Entities that early adopted the new credit impairment standard may early adopt ASU 2019-04. The Company adopted this guidance on January 1, 2020. There was no significant impact of the adoption of this guidance on the Company’s consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, Compensation-Stock Compensation: Improvements to Employee Share-Based Payment Accounting Accordingly, the Company increased its deferred tax assets by with a corresponding increase to its valuation allowance, to record previously unrecognized excess tax benefits. Additionally, the Company elected to make an accounting policy change to recognize forfeitures as they occur. As a result, the Company recorded an increase to additional paid-in capital and a corresponding increase to accumulated deficit of $0.3 million, respectively, to reflect the incremental stock-based compensation expense that would have been recognized in prior years pursuant to the modified guidance. Additionally, the Company increased its deferred tax assets by $0.1 million, with a corresponding increase to its valuation allowance, to record the excess tax benefit from the change In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) In January 2018, the FASB issued ASU 2018-01, Leases: Land Easement Practical Expedient for Transition to Topic 842 , which facilitates the implementation of ASU 2016-02. ASU 2018-01 gives entities the option to apply ASU 2016-02 as of the effective date, rather than as of the beginning of the earliest period presented. Consequently, an entity’s reporting for the comparative periods presented in the financial statements when it adopts the new leases standard will continue to be in accordance with current GAAP (ASC Topic 840) if the optional transition method is elected. The effective date of the transition requirements for the amendment is the same as the effective date and transition requirements in ASU 2016-02. The Company adopted this standard effective January 1, 2019 using the optional transition method, and chose to apply the new standard as of the effective date. Consequently, all of the Company’s operating lease commitments were recognized as lease liabilities, with corresponding right-of-use In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606)

Investments

Investments	12 Months Ended
	Dec. 31, 2019
Investments Debt And Equity Securities [Abstract]
Investments	3. Investments The carrying value and amortized cost of the Company’s investments, summarized by major security type, consisted of the following (in thousands): December 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value U.S. Treasury notes $ 228,609 $ 7 $ (13 ) $ 228,603 Government sponsored enterprise securities 88,920 5 (30 ) 88,895 Corporate debt securities 87,785 262 (8 ) 88,039 Commercial paper 102,151 61 — 102,212 $ 507,465 $ 335 $ (51 ) $ 507,749 December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Corporate debt securities $ 187,371 $ 39 $ (344 ) $ 187,066 Commercial paper 151,774 — (78 ) 151,696 $ 339,145 $ 39 $ (422 ) $ 338,762 The Company has classified all of its available-for-sale investment securities, including those with maturities beyond one year, as current assets on its consolidated balance sheets based on the highly liquid nature of the investment securities and because these investment securities are considered available for use in current operations. As of December 31, 2019 and 2018, the Company held $24.3 million and $31.8 million, respectively, of available-for-sale investment securities with contractual maturity dates more than one year and less than two years. The Company has classified all equity securities as other assets on its Consolidated Balance Sheets. At December 31, 2019 the Company had 20 securities in an unrealized loss position and at December 31, 2018 the Company had 57 securities in an unrealized loss position. The following table presents gross unrealized losses and fair value for those available-for-sale investments that were in an unrealized loss position as of December 31, 2019 and December 31, 2018, aggregated by investment category and length of time that individual securities have been in a continuous loss position (in thousands): Less Than 12 Months 12 Months or Greater Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses December 31, 2019: U.S. Treasury notes $ 148,397 $ (13 ) $ — $ — $ 148,397 $ (13 ) Government sponsored enterprise securities 61,103 (30 ) — — 61,103 (30 ) Corporate debt securities 11,334 (8 ) — — 11,334 (8 ) Total $ 220,834 $ (51 ) $ — $ — $ 220,834 $ (51 ) December 31, 2018: Corporate debt securities $ 91,265 $ (130 ) $ 44,637 $ (214 ) $ 135,902 $ (344 ) Commercial paper 151,696 (78 ) — — 151,696 (78 ) Total $ 242,961 $ (208 ) $ 44,637 $ (214 ) $ 287,598 $ (422 ) At each reporting date, the Company performs an evaluation of impairment to determine if any unrealized losses are other-than-temporary. Factors considered in determining whether a loss is other-than-temporary include the length of time and extent to which fair value has been less than the cost basis, the financial condition of the issuer, and the Company’s intent and ability to hold the investment until recovery of its amortized cost basis. The Company intends, and has the ability, to hold its investments in unrealized loss positions until their amortized cost basis has been recovered. Based on its evaluation, the Company determined that its unrealized losses were not other-than-temporary at December 31, 2019 and 2018.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	4. Fair Value Measurements The Company’s investments include cash equivalents, available-for-sale investment securities consisting of money market funds, U.S. treasury notes, and high quality, marketable debt instruments of corporations and government sponsored enterprises in accordance with the Company’s investment policy, and equity investments. The Company’s investment policy defines allowable investment securities and establishes guidelines relating to credit quality, diversification, and maturities of its investments to preserve principal and maintain liquidity. All investment securities have a credit rating of at least A3/A- or better, or P-1/A-1 or better, as determined by Moody’s Investors Service or Standard & Poor’s. The Company’s cash equivalents, available-for-sale investment securities, and equity securities are classified within the fair value hierarchy as defined by authoritative guidance. The Company’s investment securities and equity securities classified as Level 1 are valued using quoted market prices. The Company obtains the fair value of its Level 2 financial instruments from third-party pricing services. The pricing services utilize industry standard valuation models whereby all significant inputs, including benchmark yields, reported trades, broker/dealer quotes, issuer spreads, bids, offers, or other market-related data, are observable. The Company validates the prices provided by the third-party pricing services by reviewing their pricing methods and matrices, and obtaining market values from other pricing sources. After completing the validation procedures, the Company did not adjust or override any fair value measurements provided by these pricing services as of December 31, 2019 and 2018, respectively. The Company does not hold any securities classified as Level 3, which are securities valued using unobservable inputs. The Company has not transferred any investment securities between the classification levels. The recurring fair value measurements of the Company’s cash equivalents, available-for-sale investment securities, and equity securities at December 31, 2019 and 2018 consisted of the following (in thousands): Fair Value Measurements at Reporting Date Using December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Money market fund $ 98,084 $ 98,084 $ — $ — U.S. Treasury notes 228,603 228,603 — — Government sponsored enterprise securities 103,878 — 103,878 — Equity securities 2,307 2,307 — — Corporate debt securities 88,039 — 88,039 — Commercial paper 102,212 — 102,212 — $ 623,123 $ 328,994 $ 294,129 $ — Fair Value Measurements at Reporting Date Using December 31, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Money market fund $ 34,018 $ 34,018 $ — $ — Equity securities 1,309 1,309 — — Corporate debt securities 224,474 — 224,474 — Commercial paper 191,564 — 191,564 — $ 451,365 $ 35,327 $ 416,038 $ —

Balance Sheet Details

Balance Sheet Details	12 Months Ended
	Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Balance Sheet Details	5. Balance Sheet Details Inventory consisted of the following (in thousands): December 31, 2019 2018 Finished goods $ 3,175 $ 1,110 Work in process 1,685 483 Raw material 1,481 2,477 $ 6,341 $ 4,070 Property and equipment, net, consisted of the following (in thousands): December 31, 2019 2018 Computers and software $ 3,724 $ 3,745 Leasehold improvements 2,560 1,655 Furniture and fixtures 2,115 2,114 Machinery and equipment 113 — 8,512 7,514 Accumulated depreciation (5,332 ) (4,205 ) $ 3,180 $ 3,309 Depreciation of property and equipment was $1.3 million, $1.5 million, and $1.2 million for the years ended December 31, 2019, 2018, and 2017, respectively. During 2019, 2018 and 2017, the Company retired $0.2 million, $1.6 million, and $0.4 million, respectively, of fully depreciated property and equipment. Accrued liabilities consisted of the following (in thousands): December 31, 2019 2018 Accrued compensation and benefits $ 21,080 $ 17,028 Accrued research and development services 14,273 10,367 Accrued consulting and professional fees 13,691 19,325 Accrued sales allowances 11,326 5,849 Current portion of lease liabilities 3,434 — Accrued royalties 1,971 1,200 Other 1,829 2,629 $ 67,604 $ 56,398

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Stockholders' Equity	6. Stockholders’ Equity Public Offerings In September 2019, the Company raised net proceeds of approximately $271.5 million from the sale of 7,187,500 shares of its common stock in a follow-on public offering, including 937,500 shares sold pursuant to the exercise in full of the underwriters’ option to purchase additional shares. In November 2018, the Company raised net proceeds of approximately $298.5 million from the sale of 18,602,941 shares of its common stock in a follow-on public offering, including 2,426,470 shares sold pursuant to the exercise in full of the underwriters’ option to purchase additional shares. In August 2016, the Company raised net proceeds of approximately $215.9 million from the sale of 6,969,696 shares of its common stock in a follow-on public offering, including 909,090 shares sold pursuant to the exercise in full of the underwriters’ option to purchase additional shares. In January 2016, the Company raised net proceeds of approximately $281.6 million from the sale of 10,344,827 shares of its common stock in a follow-on public offering. In connection with the January 2016 offering, the Company entered into a registration rights agreement (the “Registration Rights Agreement”) with 667, L.P., Baker Brothers Life Sciences, L.P. and 14159, L.P. (the “Baker Entities”), all of which are existing stockholders of the Company and are affiliated with two of its directors, Julian C. Baker and Dr. Stephen R. Biggar. Under the Registration Rights Agreement, the Company agreed that, if the Baker Entities demand that the Company register their shares of its common stock, par value $0.0001 per share, for resale under the Securities Act of 1933, as amended (the “Securities Act”), the Company would be obligated to effect such registration. The Company’s registration obligations under the Registration Rights Agreement cover all shares of its common stock now held or later acquired by the Baker Entities (including approximately $75.0 million, $43.0 million, $200.0 million, and $62.5 million of shares that the Baker Entities purchased at the public offering price in the January 2016, August 2016, November 2018, and September 2019 offerings, respectively), will continue in effect for up to 10 years, and include the Company’s obligation to facilitate certain underwritten public offerings of its common stock by the Baker Entities in the future. The Company has agreed to bear all expenses incurred by it in effecting any registration pursuant to the Registration Rights Agreement as well as the legal expenses of the Baker Entities of up to $50,000 per underwritten public offering effected pursuant to the Registration Rights Agreement. On May 3, 2019, pursuant to the Registration Rights Agreement, the Company filed a registration statement covering all shares owned by the Baker Entities as of April 29, 2019. Private Equity Financings In December 2012, the Company raised net proceeds of $80.5 million through the sale of 19,000,000 shares of its common stock at a price of $4.43 per share and the sale of warrants to purchase 500,000 shares of its common stock at a price of $4.42 per warrant share in a private equity financing. The warrants have an exercise price of $0.01 per share. In accordance with authoritative accounting guidance, the warrants’ value of $2.2 million was determined on the date of grant using the Black-Scholes model and recorded as a component of stockholders’ equity within additional paid-in capital. Per their terms, the warrants to purchase 500,000 shares of common stock, of which 493,145 remained outstanding at December 31, 2019, may not be exercised if the holder’s ownership of the Company’s common stock would exceed 19.99 percent following such exercise. Equity Awards The Company’s 2010 Equity Incentive Plan, as amended to date (the “2010 Plan”), permits the grant of options to employees, directors and consultants. In addition, the 2010 Plan permits the grant of stock bonuses, rights to purchase restricted stock, and other stock awards. The exercise price of options granted under the 2010 Plan cannot be less than 100 percent of the fair market value of the common stock on the date of grant and the maximum term of any option is 10 years. Options granted under the 2010 Plan generally vest over a four-year Stock Options The 2004 Plan provided for the grant of options to employees, directors and consultants. The exercise price of options granted under the 2004 Plan was at 100 percent of the fair market value of the common stock on the date of grant and the maximum term of any option was 10 years. Options granted under the 2004 Plan generally vested over a four-year The following table summarizes the Company’s stock option activity during the year ended December 31, 2019: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (years) Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2018 19,868,781 $ 28.04 Granted 3,502,129 $ 28.22 Exercised (3,880,757 ) $ 24.73 Cancelled/forfeited (2,062,925 ) $ 29.10 Outstanding at December 31, 2019 17,427,228 $ 28.69 7.5 $ 247,336 Vested at December 31, 2019 8,622,679 $ 30.18 6.5 $ 109,605 Unvested at December 31, 2019 8,804,549 $ 27.23 8.5 $ 137,731 Exercisable at December 31, 2019 8,622,679 $ 30.18 6.5 $ 109,605 The aggregate intrinsic value of options exercisable as of December 31, 2019 is calculated as the difference between the exercise price of the underlying options and the closing market price of the Company’s common stock on that date, which was $42.78 per share. The aggregate intrinsic value of options exercised during the years ended December 31, 2019, 2018, and 2017 was approximately $56.6 million, $11.2 million, and $24.4 million, respectively, determined as of the date of exercise. The Company received $96.0 million in cash from options exercised during the year ended December 31, 2019. The weighted average per share fair value of options granted during the years ended December 31, 2019, 2018, and 2017 was approximately $15.97, $12.14, and $21.11, respectively. As of December 31, 2019, total unrecognized compensation cost related to stock options was approximately $119.3 million, and the weighted average period over which this cost is expected to be recognized is approximately 2.8 years. Restricted Stock Units In 2018, the Company began granting RSUs pursuant to the 2010 Plan and satisfies such grants through the issuance of new shares. RSUs are share awards that, upon vesting, will deliver to the holder shares of the Company’s common stock. RSUs generally vest over a four-year The following table summarizes the Company’s RSU activity during the year ended December 31, 2019: Number of Shares Weighted Average Grant Date Fair Value Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2018 373,706 $ 21.07 Granted 1,287,453 $ 25.22 Vested (84,409 ) $ 21.05 Cancelled/forfeited (131,587 ) $ 23.97 Outstanding at December 31, 2019 1,445,163 $ 24.50 $ 61,824 The weighted average per share fair value of RSUs granted during the years ended December 31, 2018 was approximately $21.07. As of December 31, 2019, total unrecognized compensation cost related to restricted stock options was approximately $22.7 million, and the weighted average period over which this cost is expected to be recognized is approximately 3.8 years. Employee Stock Purchase Plan The Company’s 2004 Employee Stock Purchase Plan (the “Purchase Plan”) became effective upon the closing of the Company’s initial public offering in June 2004. The Purchase Plan included an “evergreen” provision providing that a limited number of additional shares may be added to the shares authorized for issuance on the date of each annual meeting of stockholders for a period of 10 years, which ended with the meeting in 2014. In June 2016, the Company’s stockholders approved an amendment to the Purchase Plan to, among other things, increase the aggregate number of shares of common stock authorized for issuance under the plan by 400,000 shares, and at December 31, 2019, a total of 2,525,000 shares of common stock had been reserved for issuance under the Purchase Plan. At December 31, 2019, 485,254 shares of common stock remained available for issuance pursuant to the Purchase Plan. Eligible employees who elect to participate in an offering under the Purchase Plan may have up to 15 percent of their earnings withheld, subject to certain limitations, to purchase shares of common stock pursuant to the Purchase Plan. The price of common stock purchased under the Purchase Plan is equal to 85 percent of the lower of the fair market value of the common stock at the commencement date of each offering period or the relevant purchase date. During the years ended December 31, 2019, 2018, and 2017, a total of 269,037, 233,720, and 192,402 shares of common stock were issued under the Purchase Plan at average per share prices of $16.41, $15.75, and $23.50, respectively. The weighted average per share fair value of purchase rights granted during the years ended December 31, 2019, 2018, and 2017 was $14.24, $8.25, and $11.44, respectively. During the years ended December 31, 2019, 2018, and 2017, the Company recorded cash received from the exercise of purchase rights of $4.4 million, $3.7 million, and $4.5 million, respectively.

401(k) Plan

401(k) Plan	12 Months Ended
	Dec. 31, 2019
Compensation And Retirement Disclosure [Abstract]
401(k) Plan	7. 401(k) Plan Effective January 1997, the Company established a deferred compensation plan (the “401(k) Plan”) pursuant to Section 401(k) of the Internal Revenue Code of 1986, as amended (the “Code”), whereby substantially all employees are eligible to contribute up to 60 percent of their pretax earnings, not to exceed amounts allowed under the Code. The Company makes discretionary contributions to the 401(k) Plan equal to 100 percent of each employee’s pretax contributions up to 5 percent of his or her eligible compensation, subject to limitations under the Code. The Company’s total contributions to the 401(k) Plan were $4.3 million, $3.6 million, and $3.3 million for the years ended December 31, 2019, 2018, and 2017, respectively.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	8. Income Taxes Domestic and foreign pre-tax loss is as follows (in thousands): Years Ended December 31, 2019 2018 2017 Domestic $ (123,411 ) $ (78,112 ) $ (45,249 ) Foreign (110,972 ) (165,824 ) (243,035 ) $ (234,383 ) $ (243,936 ) $ (288,284 ) At December 31, 2019, the Company had federal, state, and foreign net operating loss (“NOL”) carryforwards of approximately $426.1 million, $363.2 million, and $1,004.2 million, respectively. The Company recognized state income tax provisions of $0.9 million, $1.3 million and $1.1 million for the years ended December 31, 2019, 2018 and 2017, respectively. These tax liabilities were associated with minimum taxes in the current year and the apportionment of income to certain state jurisdictions which the Company did not have corresponding NOLs in 2017 and 2018. Utilization of the domestic NOL and research and development (“R&D”) credit carryforwards may be subject to a substantial annual limitation due to ownership change limitations that have occurred or that could occur in the future, as required by Section 382 of the Code, as well as similar state and foreign provisions. These ownership changes may limit the amount of NOL and R&D credit carryforwards that can be utilized annually to offset future taxable income and tax, respectively. In general, an “ownership change” as defined by Section 382 of the Code results from a transaction or series of transactions over a three-year period resulting in an ownership change of more than 50 percentage points of the outstanding stock of a company by certain stockholders or public groups. The Company previously completed a study to assess whether an ownership change, as defined by Section 382 of the Code, had occurred from the Company’s formation through December 31, 2013. Based upon this study, the Company determined that several ownership changes had occurred. Accordingly, the Company reduced its deferred tax assets related to the federal NOL carryforwards and the federal R&D credit carryforwards that are anticipated to expire unused as a result of these ownership changes. These tax attributes were excluded from deferred tax assets with a corresponding reduction of the valuation allowance with no net effect on income tax expense or the effective tax rate. The Company completed a study through December 31, 2019 and concluded no additional ownership changes occurred. Future ownership changes may further limit the Company’s ability to utilize its remaining tax attributes. Federal and state NOL carryforwards of $6.9 million and less than $0.1 million will expire in 2025 unless utilized. The remaining federal and state NOL carryforwards will begin to expire in 2026. At December 31, 2019, the Company had federal and state charitable contribution carryforwards of $75.8 million, which will begin to expire in 2021. At December 31, 2019, the Company had $40.4 million of federal R&D credit carryforwards of which $0.2 million will expire in 2020 unless utilized, and the remaining federal R&D credit carryforwards will begin to expire in 2021. At December 31, 2019, the Company had state R&D credit carryforwards of approximately $1.5 million that will begin to expire in 2024 and $13.5 million that have no expiration date. At December 31, 2019, the Company had foreign NOL carryforwards of approximately $1,000.9 million that will begin to expire in 2022 and $3.4 million that have no expiration date. The Company continues to record the deferred tax assets related to these attributes, subject to valuation allowance, until expiration occurs. The components of the deferred tax assets are as follows (in thousands): December 31, 2019 2018 Deferred tax assets NOL carryforwards 182,948 170,476 R&D credit carryforwards 48,069 32,984 Capitalized R&D 7,607 7,421 Stock-based compensation 45,440 45,492 Intangibles 59,783 — Charitable contributions 18,303 8,530 Lease liabilities 2,366 — Other 8,568 6,220 Total deferred tax assets 373,084 271,123 Valuation allowance (370,783 ) (271,123 ) Deferred tax liabilities Right-of-use assets (2,301 ) — Total deferred tax liabilities (2,301 ) — Total net deferred tax assets $ — $ — Realization of deferred tax assets is dependent upon future earnings, if any, the timing and amount of which are uncertain. Accordingly, the deferred tax assets have been fully offset by a valuation allowance. The valuation allowance increased by approximately $99.7 million in 2019 primarily due to an increase in deferred tax assets generated from net operating losses, R&D credits and stock-based compensation expense, and the impact of the Switzerland tax reform, partially offset by the expiration of R&D credits in 2019 and the remeasurement of the Company’s deferred tax balance for changes in future tax rates. In December 2017, the Tax Cuts and Jobs Act (the “2017 Tax Act”) was enacted. The 2017 Tax Act included a number of changes to existing U.S. tax laws that impact the Company, most notably a reduction of the U.S. corporate income tax rate from 35 percent to 21 percent for tax years beginning after December 31, 2017. The 2017 Tax Act also provided for a one-time transition tax on certain foreign earnings, the acceleration of depreciation for certain assets placed into service after September 27, 2017 as well as prospective changes beginning in 2018, including repeal of the domestic manufacturing deduction, acceleration of tax revenue recognition, global intangible low taxed income, foreign derived intangible income deduction, additional limitations on executive compensation and limitations on the deductibility of interest. During 2019, Switzerland implemented tax reform that is effective for tax years 2020 and forward. As a result, the Company has remeasured the deferred tax assets, primarily comprised of net operating loss carryforwards, at the amount and rate in which it is anticipated they will reverse. Due to the enactment of the cantonal law, the Company recognized a deferred tax asset of $57.0 million in the fourth quarter of 2019, which was fully offset with a valuation allowance. The amount primarily related to deferred tax benefits associated with an allowed step-up of intangible assets for tax purposes. The Company must elect certain components of the Swiss tax reform when it files the 2019 tax return. The Company will continue to monitor Swiss tax reform for any additional interpretative guidance that could result in changes to the amounts that have been recorded. A reconciliation of income taxes to the amount computed by applying the statutory federal income tax rate to the pretax loss is summarized as follows (in thousands): Years Ended December 31, 2019 2018 2017 Amounts computed at statutory federal rate $ (49,365 ) $ (51,226 ) $ (98,016 ) Stock-based compensation and other permanent differences 6,070 3,432 1,341 R&D credits (16,687 ) (7,941 ) (5,573 ) Change in valuation allowance 99,846 34,333 (28,230 ) State taxes (2,138 ) (1,017 ) (26 ) Contingencies 1,861 2,938 360 Foreign rate differential 20,413 20,896 61,480 Tax Cuts and Jobs Act — — 68,889 Switzerland Tax Reform (59,181 ) — — Other 57 (159 ) 894 Income tax expense $ 876 $ 1,256 $ 1,119 The tax years 2000-2018 remain open to examination by the major taxing jurisdictions to which the Company is subject. The Company recognizes a tax benefit from an uncertain tax position when it is more likely than not that the position will be sustained upon examination. The Company recorded an uncertain tax position reserve of $1.9 million, $3.1 million and $0.4 million for the years ended December 31, 2019, 2018 and 2017, respectively. In addition, due to the 2017 Tax Act, an adjustment of $1.1 million was made to remeasure the uncertain tax position reserve at December 31, 2017. Due to the valuation allowance recorded against the Company’s deferred tax assets, an immaterial amount of the total unrecognized tax benefits as of December 31, 2019 would reduce the annual effective tax rate if recognized. The Company does not anticipate that the amount of unrecognized tax benefits as of December 31, 2019 will significantly change within the next twelve months. The Company’s practice is to recognize interest and/or penalties related to uncertain income tax positions in income tax expense. The Company had no interest and/or penalties accrued on the Company’s consolidated balance sheets at December 31, 2019 or 2018, respectively. Further, the Company did not recognize any interest and/or penalties in the statement of operations for the years ended December 31, 2019, 2018 and 2017, respectively, related to uncertain tax positions. The following table provides a reconciliation of changes in unrecognized tax benefits (in thousands): Years Ended December 31, 2019 2018 2017 Balance at beginning of period $ 5,037 $ 1,933 $ 2,664 Additions related to current period tax positions 1,908 3,104 361 Impact of Tax Cuts and Jobs Act — — (1,092 ) Balance at end of period $ 6,945 $ 5,037 $ 1,933

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	9. Commitments and Contingencies Royalty Payments Pursuant to the terms of its 2006 license agreement with the Ipsen Group, the Company is required to make royalty payments of two percent of net sales of NUPLAZID. License Agreements In May 2018, the Company signed an Exclusivity Deed (the “Deed”) with Neuren Pharmaceuticals Limited (“Neuren”) that provided for exclusive negotiations for a period of three months from the date of the Deed. Under the terms of the Deed, the Company invested $3.1 million to subscribe for 1,330,000 shares of Neuren and paid $0.9 million for the exclusive right to negotiate a deal with Neuren, which was recorded in selling, general and administrative expenses in the Consolidated Statements of Operations in the second quarter of 2018. At December 31, 2019, the Company continues to hold the equity securities as a strategic investment in which the Company does not have a controlling interest or significant influence. Publicly held equity securities are measured using quoted prices in their respective active markets with changes recorded through other expense on the statements of operations. Net gain on the strategic investments recognized in other expense in the Consolidated Statements of Operations for the year ended December 31, 2019 was $1.0 million and net loss on strategic investments recognized for the year ended December 31, 2018 was $1.8 million. As of December 31, 2019 and 2018, the aggregate carrying amount of the Company’s strategic equity investment was $2.3 million and $1.3 million, respectively, included in other assets on the Consolidated Balance Sheets. In August 2018, the Company entered into a license agreement with Neuren and obtained exclusive North American rights to develop and commercialize trofinetide for Rett syndrome and other indications. Under the terms of the agreement, Neuren received an upfront payment of $10.0 million and is eligible to receive milestone payments of up to $455.0 million, based on the achievement of certain development and annual net sales milestones. In addition, Neuren is eligible to receive tiered, escalating, double-digit percentage royalties based on net sales. The license agreement was accounted for as an asset acquisition and the upfront cash payment of $10.0 million was recorded in research and development expenses in the Consolidated Statements of Operations in the third quarter of 2018, as there is no alternative use for the asset. Corporate Credit Card Program In connection with the Company’s credit card program, the Company established a letter of credit in 2016 for $2.0 million, which has automatic annual extensions and is fully secured by restricted cash. Fleet Program In connection with the Company’s fleet program, the Company established a letter of credit for $0.4 million, which has automatic annual extensions and is fully secured by restricted cash. Legal Proceedings Between July 19 and August 3, 2018, following negative publicity about NUPLAZID, three purported company stockholders filed putative securities class action complaints (captioned Staublein v. ACADIA Pharmaceuticals, Inc., Case No. 18-cv-01647, Stone v. ACADIA Pharmaceuticals Inc., Case No. 18-cv-01672, and Barglow v. ACADIA Pharmaceuticals Inc., Case No. 18-cv-01812) in the U.S. District Court for the Southern District of California against the Company and certain of its current and former executive officers. Thereafter, several putative lead plaintiffs filed motions to consolidate the cases and to appoint a lead plaintiff. On January 3, 2019, the Court consolidated the cases under the caption In re ACADIA Pharmaceuticals Inc. Securities Litigation, Case No. 18-cv-01647, and took the lead plaintiff motions under submission. On February 26, 2019, the Court appointed a lead plaintiff and lead counsel. Lead plaintiff filed a consolidated complaint on April 15, 2019. The consolidated complaint generally alleges that defendants violated Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 by making materially false and misleading statements regarding the Company’s business, operations, and prospects by failing to disclose that adverse events and safety concerns regarding NUPLAZID threatened initial and continuing FDA approval, and by failing to disclose that the Company engaged in business practices likely to attract regulatory scrutiny. The consolidated complaint seeks unspecified monetary damages and other relief. Defendants filed a motion to dismiss the consolidated complaint on June 7, 2019 and the lead plaintiff filed an opposition on July 23, 2019. Defendants filed a reply on August 22, 2019. On November 12, 2019, the Court determined that the motion to dismiss was suitable for resolution without oral argument and took the motion hearing off calendar. On February 7, 2020, a purported company stockholder filed a derivative complaint (captioned Barney v. Davis et al., Case No. 20-cv-0238) in the U.S. District Court for the Southern District of California against the Company’s directors and certain of its current and former executive officers. The complaint asserts claims for breach of fiduciary duty, waste of corporate assets, and unjust enrichment arising from allegations similar to those in the federal securities class action described above. On February 19, 2020, the Court granted the parties’ stipulation to stay the derivative action pending a ruling on the motion to dismiss in the federal securities class action. G iven the unpredictability inherent in litigation, the Company cannot predict the outcome of th ese matter s . The Company is unable to estimate possible losses or ranges of losses that may result from these matter s , and therefore it ha s not accrued any amounts in connection with these matter s other than attorneys’ fees incurred to date . Government Investigation In September 2018 the Company received a civil investigative demand (“CID”) from the Department of Justice (“DOJ”) requesting certain documents and information related to the Company’s sales and marketing of NUPLAZID. The Company is cooperating with the DOJ’s request. Responding to the CID will require considerable resources and no assurance can be given as to the timing or outcome of the DOJ’s investigation.

Leases

Leases	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Leases	10. Leases The Company leases facilities and certain equipment under noncancelable operating leases that expire at various dates through February 2031. Under the terms of the facilities leases, the Company is required to pay its proportionate share of property taxes, insurance and normal maintenance costs. In 2015, the Company entered into a master lease agreement giving the Company the ability to lease vehicles under operating leases with initial terms of 36 months from the date of delivery. In 2018, the lease agreement was terminated and a new master lease agreement was entered into with a new vendor giving the Company the ability to lease vehicles under operating leases with initial terms ranging from 12 to 50 months from the date of delivery. The Company adopted Topic 842 as of January 1, 2019. Prior period amounts have not been adjusted and continue to be reported in accordance with the Company’s historic accounting under Topic 840. Therefore, there were no lease liabilities or right-of-use assets in 2018 The Company leases facilities and certain equipment under noncancelable operating leases with remaining lease terms of 0.3 year to 6.1 years, one of which includes an option to extend the lease for one five-year The operating Years Ended December 31, 2019 2018 2017 Operating lease cost $ 5,155 $ 4,503 $ 3,828 Supplemental cash flow information related to the Company’s leases were as follows (in thousands): Year Ended December 31, 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 4,841 Right-of-use assets obtained in exchange for operating lease obligations: 13,399 The balance sheet classification of the Company’s lease liabilities was as follows (in thousands): December 31, 2019 Operating lease liabilities Current portion included in accrued liabilities $ 3,434 Operating lease liabilities 6,361 Total operating lease liabilities $ 9,795 Maturities of lease liabilities were as follows (in thousands): Operating Leases Years ending December 31, 2020 $ 3,563 2021 2,660 2022 2,089 2023 1,192 2024 1,080 Thereafter 1,011 Total lease payments 11,595 Less: Imputed interest (1,800 ) Total operating lease liabilities $ 9,795 Operating lease liabilities are based on the net present value of the remaining lease payments over the remaining lease term. In determining the present value of lease payments, the Company uses its incremental borrowing rate based on the information available at the lease commencement date. As of December 31, 2019, the weighted average remaining lease term is 4.7 years and the weighted average discount rate used to determine the operating lease liability was 8.0%. In the fourth quarter of 2018, the Company entered into an agreement to lease a new corporate office space in San Diego, California with total minimum lease payments of $53.7 million over an initial term of 10 years and 9 months. As of December 31, 2019, the lease had not yet commenced. This operating lease is expected to commence in the third quarter of 2020, but may commence earlier if the lessor makes the space available for use earlier than anticipated. In connection with this lease agreement, the Company established a letter of credit for $2.2 million, which has automatic annual extensions and is fully secured by restricted cash. Disclosures related to periods prior to adoption of the New Lease Standard Estimated annual future minimum payments related to the Company’s operating leases and other long-term contractual obligations were as follows at December 31, 2018 (in thousands): 2019 $ 4,770 2020 4,170 2021 6,906 2022 7,181 2023 6,568 Thereafter 38,683 $ 68,278

Selected Quarterly Financial Da

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data (Unaudited)	11. Selected Quarterly Financial Data (Unaudited) The following financial information reflects all normal recurring adjustments, which are, in the opinion of management, necessary for a fair statement of the results of the interim periods. Summarized quarterly data for the years ended December 31, 2019 and 2018 are as follows (in thousands, except per share data): Fiscal Year 2019 Quarters 1st 2nd 3rd 4th Total Revenues $ 62,959 $ 83,205 $ 94,586 $ 98,326 $ 339,076 Gross profit (1) $ 60,009 $ 80,247 $ 92,170 $ 95,306 $ 327,732 Net loss $ (85,304 ) $ (54,941 ) $ (41,978 ) $ (53,036 ) $ (235,259 ) Basic and diluted net loss per share (2) $ (0.59 ) $ (0.38 ) $ (0.29 ) $ (0.34 ) $ (1.60 ) Fiscal Year 2018 Quarters 1st 2nd 3rd 4th Total Revenues $ 48,868 $ 57,063 $ 58,305 $ 59,571 $ 223,807 Gross profit (1) $ 46,715 $ 53,501 $ 54,466 $ 56,748 $ 211,430 Net loss $ (54,296 ) $ (63,266 ) $ (62,138 ) $ (65,492 ) $ (245,192 ) Basic and diluted net loss per share (2) $ (0.44 ) $ (0.51 ) $ (0.50 ) $ (0.50 ) $ (1.94 ) ( 1 ) Determined by subtracting cost of product sales from product sales, net. ( 2 ) Net loss per common share, basic and diluted, are computed independently for each quarter and the full year based upon respective average shares outstanding. Therefore, the sum of the quarterly net loss per common share amounts may not equal the annual amounts reported.

Subsequent Event

Subsequent Event	12 Months Ended
	Dec. 31, 2019
Subsequent Events [Abstract]
Subsequent Event	12. Subsequent Event In February 2020, the Company entered into an amendment to the lease agreement dated October 4, 2018 to lease approximately 31,608 square feet of additional corporate office space in San Diego, California with total minimum lease payments of $25.3 million over an initial term of 10 years and 7 months. This operating lease is expected to commence in the third quarter of 2020, but may commence earlier if the lessor makes the space available for use earlier than anticipated.

SCHEDULE II - Valuation and Qua

SCHEDULE II - Valuation and Qualifying Accounts	12 Months Ended
	Dec. 31, 2019
Valuation And Qualifying Accounts [Abstract]
SCHEDULE II - Valuation and Qualifying Accounts	SCHEDULE II – Valuation and Qualifying Accounts (in thousands) Additions Deductions Balance at Beginning of Period Provision Related to Current Period Sales Actual Distribution Fees, Discounts and Chargebacks Related to Current Period Sales Actual Distribution Fees, Discounts and Chargebacks Related to Prior Period Sales Balance at En d Allowance for distribution fees, discounts and chargebacks: For the year ended December 31, 2017 $ 201 $ 12,837 $ (12,591 ) $ (201 ) $ 246 For the year ended December 31, 2018 $ 246 $ 24,613 $ (22,773 ) $ (246 ) $ 1,840 For the year ended December 31, 2019 $ 1,840 $ 33,827 $ (31,251 ) $ (1,840 ) $ 2,576

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries located in Europe. All intercompany accounts and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with a maturity date at the date of purchase of three months or less to be cash equivalents. The following table provides a reconciliation of cash, cash equivalents and restricted cash reported in the consolidated balance sheets that sum to the total of the same such amounts shown in the Consolidated Statements of Cash Flows (in thousands). Twelve Months Ended December 31, 2019 Twelve Months Ended December 31, 2018 Beginning of period End of period Beginning of period End of period Cash and cash equivalents $ 134,758 $ 189,680 $ 69,418 $ 134,758 Restricted cash 4,826 4,787 2,475 4,826 Total cash, cash equivalents and restricted cash shown in the statements of cash flows $ 139,584 $ 194,467 $ 71,893 $ 139,584
Investment Securities	Investment Securities The Company has classified all of its investment securities as available-for-sale as the sale of such securities may be required prior to maturity to implement management strategies, and accordingly, carries these investments at fair value. Unrealized gains and losses, if any, are reported as a separate component of stockholders’ equity. The cost of investment securities classified as available-for-sale is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion are included in interest income. Realized gains and losses, if any, are also included in interest income. The cost of securities sold is based on the specific identification method.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The carrying values of the Company’s financial instruments, consisting of cash and cash equivalents, trade receivables, interest and other receivables, restricted cash, and accounts payable and accrued liabilities, approximate fair value due to the relative short-term nature of these instruments. As disclosed in Note 4, the Company classifies its cash equivalents and available-for-sale investment securities within the fair value hierarchy as defined by authoritative guidance: Level 1 Inputs — Quoted prices for identical instruments in active markets. Level 2 Inputs — Quoted prices for similar instruments in active markets; quoted prices for identical or similar instruments in markets that are not active; and model-derived valuations in which all significant inputs and significant value drivers are observable. Level 3 Inputs — Valuation derived from valuation techniques in which one or more significant inputs or significant value drivers are unobservable.
Accounts Receivable	Accounts Receivable Accounts receivable are recorded net of customer allowances for distribution fees, prompt payment discounts, chargebacks, and doubtful accounts. Allowances for distribution fees, prompt payment discounts and chargebacks are based on contractual terms. The Company estimates the allowance for doubtful accounts based on existing contractual payment terms, actual payment patterns of its customers and individual customer circumstances. At December 31, 2019, the Company determined that an allowance for doubtful accounts was not required. No accounts were written off during the year ended December 31, 2019. During the year ended December 31, 2018, the Company wrote off less than $0.1 million.
Inventory	Inventory Inventory is stated at the lower of cost or net realizable value under the first-in, first-out method, or FIFO. The Company uses a combination of standard and actual costing methodologies to determine the cost basis for its inventories which approximates actual costs. Inventory consists of raw material, work in process, and finished goods, including third-party manufacturing costs, freight, and indirect overhead costs. The Company capitalizes inventory costs associated with its products upon regulatory approval when, based on management’s judgment, future commercialization is considered probable and the future economic benefit is expected to be realized; otherwise, such costs are expensed. Prior to FDA approval of NUPLAZID in April 2016, all costs related to the manufacturing of NUPLAZID were charged to research and development expense in the period incurred. The Company periodically reviews inventory and reduces the carrying value of items to net realizable value for potentially excess, dated or obsolete inventory based on an analysis of forecasted demand compared to quantities on hand and any firm purchase orders, as well as product shelf life. During the years ended December 31, 2019, 2018 and 2017, the Company recorded charges of $1.1 million, $2.7 million and $0.7 million, respectively, to reduce certain finished goods and work in process inventory to its net realizable value.
Property and Equipment	Property and Equipment Property and equipment are recorded at cost and depreciated over their estimated useful lives using the straight-line method. Leasehold improvements are amortized over the shorter of their estimated useful lives or the term of the lease by use of the straight-line method. Construction-in-process reflects amounts incurred for property, equipment or improvements that have not been placed in service. Maintenance and repair costs are expensed as incurred. When assets are retired or sold, the assets and accumulated depreciation are removed from the respective accounts and any gain or loss is recognized. Estimated useful lives by major asset category are as follows: Useful Lives Machinery and equipment 5 to 7 years Computers and software 3 years Furniture and fixtures 10 years
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company reviews its long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability is measured by a comparison of the carrying amount of an asset to estimated undiscounted future cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated future cash flows, an impairment charge is recognized by the amount by which the carrying amount of the asset exceeds the fair value of the asset. Through December 31, 2019, no such impairment losses have been recorded by the Company.
License Fees and Royalties	License Fees and Royalties The Company expenses amounts paid to acquire licenses associated with products under development when the ultimate recoverability of the amounts paid is uncertain and the technology has no alternative future use when acquired. Acquisitions of technology licenses are charged to expense or capitalized based upon management’s assessment regarding the ultimate recoverability of the amounts paid and the potential for alternative future use. The Company has determined that technological feasibility for its product candidates is reached when the requisite regulatory approvals are obtained to make the product available for sale. In connection with the FDA approval of NUPLAZID in April 2016, the Company made a one-time milestone payment of $8.0 million pursuant to its 2006 license agreement with the Ipsen Group in which the Company licensed certain intellectual property rights that complement its patent portfolio for its serotonin platform, including NUPLAZID. The Company capitalized the $8.0 million payment as an intangible asset and is amortizing the asset on a straight-line basis over the estimated useful life of the licensed patents through the second half of 2021. The Company recorded amortization expense related to its intangible asset of $1.5 million for each of the years ended December 31, 2019, 2018 and 2017. As of December 31, 2019, estimated future amortization expense related to the Company’s intangible asset was $1.5 million for 2020, and $1.0 million for 2021. Royalties incurred in connection with the Company’s license agreement with the Ipsen Group, as disclosed in Note 9, are expensed to license fees and royalties as revenue from product sales is recognized.
Advertising Expense	Advertising Expense In connection with the FDA approval and commercial launch of NUPLAZID in 2016, the Company began to incur advertising costs. Advertising costs are expensed when services are performed or goods are delivered. The Company incurred $38.3 million, $39.8 million and $15.6 million in advertising costs during the years ended December 31, 2019, 2018 and 2017, respectively, related to its marketed product, NUPLAZID. No advertising costs were capitalized as prepaid expenses at December 31, 2019 or 2018.
Revenue Recognition	Revenue Recognition Product Sales, Net Effective January 1, 2018, the Company adopted ASU 2014-09, Revenue from Contracts with Customers (Topic 606), No cumulative effect adjustment to the opening balance of retained earnings was necessary upon adoption, and there is no reconciliation of the Company’s Consolidated Statements of Operations, as no revenue recognition differences were identified when comparing the revenue recognition criteria under Topic 606 to previous requirements The Company’s net product sales consist of U.S. sales of NUPLAZID. NUPLAZID was approved by the FDA in April 2016 and the Company commenced shipments of NUPLAZID to specialty pharmacies (“SPs”) and specialty distributors (“SDs”) in late May 2016. SPs dispense product to a patient based on the fulfillment of a prescription and SDs sell product to government facilities, long-term care pharmacies, or in-patient hospital pharmacies. Product shipping and handling costs are included in cost of product sales. The Company recognizes revenue from product sales at the net sales price (the “transaction price”) which includes estimates of variable consideration for which reserves are established and reflects each of these as either a reduction to the related account receivable or as an accrued liability, depending on how the amount payable is settled. Overall, these reserves reflect the Company’s best estimates of the amount of consideration to which the Company is entitled based on the terms of the contract. The amount of variable consideration that is included in the transaction price may be constrained, and is included in the net sales price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from estimates, the Company may need to adjust its estimates, which would affect net revenue in the period of adjustment Distribution Fees : Distribution fees include distribution service fees paid to the SPs and SDs based on a contractually fixed percentage of the wholesale acquisition cost (“WAC”), fees for data, and prompt payment discounts. Distribution fees are recorded as an offset to revenue based on contractual terms at the time revenue from the sale is recognized . Rebates : Allowances for rebates include mandated discounts under the Medicaid Drug Rebate Program and the Medicare Part D prescription drug benefit. Rebates are amounts owed after the final dispensing of the product to a benefit plan participant and are based upon contractual agreements with, or statutory requirements pertaining to, Medicaid and Medicare benefit providers. The allowance for rebates is based on statutory discount rates, estimated payor mix, and expected utilization. The Company’s estimates for expected utilization of rebates are based on historical data received from the SPs and SDs since product launch. Rebates are generally invoiced and paid in arrears so that the accrual balance consists of an estimate of the amount expected to be incurred for the current quarter’s activity, plus an accrual balance for prior quarters’ unpaid rebates . Chargebacks : Chargebacks are discounts and fees that relate to contracts with government and other entities purchasing from the SDs at a discounted price. The SDs charge back to the Company the difference between the price initially paid by the SDs and the discounted price paid to the SDs by these entities. The Company also incurs group purchasing organization fees for transactions through certain purchasing organizations. The Company estimates sales with these entities and accrues for anticipated chargebacks and organization fees, based on the applicable contractual terms . Co-Payment Assistance : The Company offers co-payment assistance to commercially insured patients meeting certain eligibility requirements. Co-payment assistance is accrued for based on actual program participation and estimates of program redemption using data provided by third-party administrators . Product Returns : Consistent with industry practice, the Company offers the SPs and SDs limited product return rights for damages, shipment errors, and expiring product; provided that the return is within a specified period around the product expiration date as set forth in the applicable individual distribution agreement. The Company does not allow product returns for product that has been dispensed to a patient. As the Company receives inventory reports from the SPs and SDs and has the ability to control the amount of product that is sold to the SPs and SDs, it is able to make a reasonable estimate of future potential product returns based on this on-hand channel inventory data and sell-through data obtained from the SPs and SDs. In arriving at its estimate for product returns, the Company also considers historical product returns, the underlying product demand, and industry data specific to the specialty pharmaceutical distribution industry .
Research and Development Expenses	Research and Development Expenses Research and development expenses are charged to operations as incurred. Research and development expenses include costs associated with services provided by contract organizations for preclinical development, pre-commercialization manufacturing expenses, and clinical trials, salaries and related personnel expenses including stock-based compensation expense, and facilities and equipment expenses. The Company accrues for costs incurred as the services are being provided by monitoring the status of the trial or services provided and the invoices received from its external service providers. When the Company makes payments in advance of services being provided, we record those amounts as prepaid expenses on our consolidated balance sheet and expense them as the services are rendered.
Concentration Risk	Concentration Risk Financial instruments, which potentially subject the Company to concentrations of credit risk, principally consist of cash, cash equivalents, investment securities, accounts receivable, and restricted cash. The Company invests its excess cash primarily in money market funds, U.S. treasury notes, and high quality, marketable debt instruments of corporations and government sponsored enterprises in accordance with the Company’s investment policy. The Company’s investment policy defines allowable investments and establishes guidelines relating to credit quality, diversification, and maturities of its investments to preserve principal and maintain liquidity. All investment securities have a credit rating of at least A3/A- or better, or P-1/A-1 or better, as determined by Moody’s Investors Service or Standard & Poor’s. Further, the Company specifies credit quality standards for its customers that are designed to limit the Company’s credit exposure to any single party. The Company does not currently have any of its own manufacturing facilities, and therefore it depends on an outsourced manufacturing strategy for the production of NUPLAZID for commercial use and for the production of its product candidates for clinical trials. The Company has contracts in place with two third-party manufacturers of commercial drug product and one third-party manufacturer of drug substance that is approved for the production of NUPLAZID active pharmaceutical ingredient (“API”). Although there are potential sources of supply other than the Company’s existing suppliers, any new supplier would be required to qualify under applicable regulatory requirements. The Company has entered into distribution agreements with a limited number of SPs and SDs, and all of the Company’s product sales are to these customers. For the year ended December 31, 2019, the Company’s four largest customers represented approximately 77% of the Company’s product revenue and 75% of the Company’s accounts receivable balance at December 31, 2019. For the year ended December 31, 2018, the Company’s four largest customers represented approximately 85% of the Company’s product revenue and 84% of the Company’s accounts receivable balance at December 31, 2018. For the year ended December 31, 2017, the Company’s four largest customers represented approximately 89% of the Company’s product revenue and 87% of the Company’s accounts receivable balance at December 31, 2017.
Stock-Based Compensation	Stock-Based Compensation The fair value of each employee stock option and each employee stock purchase right granted is estimated on the grant date under the fair value method using the Black-Scholes valuation model. The estimated fair value of each stock option and purchase right is then expensed over the requisite service period, which is generally the vesting period. The following weighted-average assumptions were used during these periods: Years Ended December 31, 2019 2018 2017 Stock Options: Expected volatility 62 % 71 % 68 % Risk-free interest rate 2 % 3 % 2 % Expected dividend yield 0 % 0 % 0 % Expected life of options in years 5.7 5.7 5.8 Years Ended December 31, 2019 2018 2017 Employee Stock Purchase Plan: Expected volatility 62%-86% 59%-79% 44%-62% Risk-free interest rate 1.5%-2.4% 2.1%-2.8% 1.0%-1.7% Expected dividend yield 0 % 0 % 0 % Expected life in years 0.5-2.0 0.5-2.0 0.5-2.0 Expected Volatility. The Company considers its historical volatility and implied volatility when determining the expected volatility. Risk-Free Interest Rate. The Company determines its risk-free interest rate assumption based on the U.S. Treasury yield for obligations with contractual terms similar to the expected term of the stock option or purchase right being valued. Expected Dividend Yield. The Company has never paid any dividends and currently has no plans to do so. Expected Life. In determining the expected life for stock options, the Company considers, among other factors, its historical exercise experience to date as well as the mean time remaining to full vesting of all outstanding options and the mean time remaining to the end of the contractual term of all outstanding options. The estimated life for the Company’s employee stock purchase rights is based upon the terms of each offering period. The fair value of restricted stock units (“RSUs”) is estimated based on the closing market price of the Company’s common stock on the date of grant. RSUs generally vest annually over a four-year period. The table below summarizes the total stock-based compensation expense included in the Company’s statements of operations for the periods presented (in thousands): Years Ended December 31, 2019 2018 2017 Cost of product sales $ 2,936 $ 3,863 $ 3,690 Research and development 32,533 32,038 26,485 Sales, general and administrative 46,796 45,663 45,357 $ 82,265 $ 81,564 $ 75,532
Income Taxes	Income Taxes Current income tax expense or benefit represents the amount of income taxes expected to be payable or refundable for the current year. A deferred income tax asset or liability is computed for the expected future impact of differences between the financial reporting and income tax bases of assets and liabilities and for the expected future tax benefit to be derived from tax credits and loss carryforwards. Deferred income tax expense or benefit represents the net change during the year in the deferred income tax asset or liability. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized. The Company recognizes the impact of a tax position in the financial statements only if that position is more likely than not of being sustained upon examination by taxing authorities, based on the technical merits of the position. Any interest and penalties related to uncertain tax positions will be reflected in income tax expense.
Net Loss Per Share	Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted average number of common shares outstanding for the period, without consideration for common stock equivalents. Diluted net loss per share is computed by dividing the net loss by the weighted average number of common shares and common stock equivalents outstanding for the period determined using the treasury stock method. For purposes of this calculation, stock options, employee stock purchase rights, RSUs, and warrants are considered to be common stock equivalents but are not included in the calculations of diluted net loss per share for the periods presented as their effect would be antidilutive. The Company incurred net losses for all periods presented and there were no reconciling items for potentially dilutive securities. More specifically, at December 31, 2019, 2018 and 2017, options, employee stock purchase rights, RSUs, and warrants totaling approximately 19,516,000 shares, 20,824,000 shares and 18,526,000 shares, respectively, were excluded from the calculation of diluted net loss per share as their effect would have been anti-dilutive.
Segment Reporting	Segment Reporting Management has determined that the Company operates in one business segment which is the development and commercialization of innovative medicines. All revenues for the years ended December 31, 2019, 2018 and 2017 were generated in the United States.
Recently Issued Accounting Standards	Recently Issued Accounting Standards In December 2017, the Tax Cuts and Jobs Act (the “2017 Tax Act”) was enacted. The 2017 Tax Act includes a number of changes to existing U.S. tax laws that impact the company, most notably a reduction of the U.S. corporate income tax rate from 35 percent to 21 percent for tax years beginning after December 31, 2017. The 2017 Tax Act also provides for a one-time transition tax on certain foreign earnings and the acceleration of depreciation for certain assets placed into service after September 27, 2017 as well as prospective changes beginning in 2018, including repeal of the domestic manufacturing deduction, acceleration of tax revenue recognition, global intangible low taxed income, foreign derived intangible income deduction, additional limitations on executive compensation and limitations on the deductibility of interest. The Company recognized the income tax effects of the 2017 Tax Act in its 2017 financial statements in accordance with Staff Accounting Bulletin No. 118, which provides SEC staff guidance for the application of ASC Topic 740, Income Taxes In November 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-18, Statement of Cash Flows: Restricted Cash This guidance was effective for fiscal years beginning after December 15, 2017, and interim periods within those fiscal years. The Company adopted this guidance on January 1, 2018, using a retrospective transition method. The adoption of this ASU impacted the presentation of cash flows, with inclusion of restricted cash flows for each of the presented periods In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments , which changes the impairment model for most financial assets and certain other instruments. For trade receivables and other instruments, entities will be required to use a new forward-looking expected loss model that generally will result in the earlier recognition of allowances for losses. For available-for-sale debt securities with unrealized losses, the losses will be recognized as allowances rather than as reductions in the amortized cost of the securities. This guidance is effective for annual reporting periods beginning after December 15, 2019, including interim periods within those years, with early adoption permitted only as of annual reporting periods beginning after December 15, 2018. The Company adopt ed this guidance on January 1, 2020. The adoption of ASU 2016-13 did not have material impact on the Company’s consolidated financial statements. In April 2019 , the FASB issued ASU 2019-04, Codification Improvements to Topic 326, Financial Instruments—Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments , which, among other things, provides entities with practical expedients and policy elections related to the presentation and disclosure of accrued interest and the related allowance for credit losses and clarifies how to disclose line-of-credit arrangements that are converted to term loans in the vintage table disclosure. ASU 2019-04 has the same effective date as the new credit impairment standard for entities that have not yet adopted the standard. For entities that early adopted the new credit impairment standard, ASU 2019-04 is effective for fiscal years beginning after December 15, 2019 and interim periods therein. Entities that early adopted the new credit impairment standard may early adopt ASU 2019-04. The Company adopted this guidance on January 1, 2020. There was no significant impact of the adoption of this guidance on the Company’s consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, Compensation-Stock Compensation: Improvements to Employee Share-Based Payment Accounting Accordingly, the Company increased its deferred tax assets by with a corresponding increase to its valuation allowance, to record previously unrecognized excess tax benefits. Additionally, the Company elected to make an accounting policy change to recognize forfeitures as they occur. As a result, the Company recorded an increase to additional paid-in capital and a corresponding increase to accumulated deficit of $0.3 million, respectively, to reflect the incremental stock-based compensation expense that would have been recognized in prior years pursuant to the modified guidance. Additionally, the Company increased its deferred tax assets by $0.1 million, with a corresponding increase to its valuation allowance, to record the excess tax benefit from the change In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) In January 2018, the FASB issued ASU 2018-01, Leases: Land Easement Practical Expedient for Transition to Topic 842 , which facilitates the implementation of ASU 2016-02. ASU 2018-01 gives entities the option to apply ASU 2016-02 as of the effective date, rather than as of the beginning of the earliest period presented. Consequently, an entity’s reporting for the comparative periods presented in the financial statements when it adopts the new leases standard will continue to be in accordance with current GAAP (ASC Topic 840) if the optional transition method is elected. The effective date of the transition requirements for the amendment is the same as the effective date and transition requirements in ASU 2016-02. The Company adopted this standard effective January 1, 2019 using the optional transition method, and chose to apply the new standard as of the effective date. Consequently, all of the Company’s operating lease commitments were recognized as lease liabilities, with corresponding right-of-use In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606)

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash	The following table provides a reconciliation of cash, cash equivalents and restricted cash reported in the consolidated balance sheets that sum to the total of the same such amounts shown in the Consolidated Statements of Cash Flows (in thousands). Twelve Months Ended December 31, 2019 Twelve Months Ended December 31, 2018 Beginning of period End of period Beginning of period End of period Cash and cash equivalents $ 134,758 $ 189,680 $ 69,418 $ 134,758 Restricted cash 4,826 4,787 2,475 4,826 Total cash, cash equivalents and restricted cash shown in the statements of cash flows $ 139,584 $ 194,467 $ 71,893 $ 139,584
Schedule of Estimated Useful Lives by Major Asset Category	Estimated useful lives by major asset category are as follows: Useful Lives Machinery and equipment 5 to 7 years Computers and software 3 years Furniture and fixtures 10 years
Weighted-Average Assumptions Used to Estimate Fair Value of Employee Stock Options	The estimated fair value of each stock option and purchase right is then expensed over the requisite service period, which is generally the vesting period. The following weighted-average assumptions were used during these periods: Years Ended December 31, 2019 2018 2017 Stock Options: Expected volatility 62 % 71 % 68 % Risk-free interest rate 2 % 3 % 2 % Expected dividend yield 0 % 0 % 0 % Expected life of options in years 5.7 5.7 5.8
Weighted-Average Assumptions Used to Estimate Fair Value of Employee Stock Purchase Plan Rights	Years Ended December 31, 2019 2018 2017 Employee Stock Purchase Plan: Expected volatility 62%-86% 59%-79% 44%-62% Risk-free interest rate 1.5%-2.4% 2.1%-2.8% 1.0%-1.7% Expected dividend yield 0 % 0 % 0 % Expected life in years 0.5-2.0 0.5-2.0 0.5-2.0
Summary of Stock-based Compensation Expense Included in Statements of Operations	The table below summarizes the total stock-based compensation expense included in the Company’s statements of operations for the periods presented (in thousands): Years Ended December 31, 2019 2018 2017 Cost of product sales $ 2,936 $ 3,863 $ 3,690 Research and development 32,533 32,038 26,485 Sales, general and administrative 46,796 45,663 45,357 $ 82,265 $ 81,564 $ 75,532

Investments (Tables)

Investments (Tables)	12 Months Ended
	Dec. 31, 2019
Investments Debt And Equity Securities [Abstract]
Carrying Value and Amortized Cost of Company’s Investments Summarized by Major Security Type	The carrying value and amortized cost of the Company’s investments, summarized by major security type, consisted of the following (in thousands): December 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value U.S. Treasury notes $ 228,609 $ 7 $ (13 ) $ 228,603 Government sponsored enterprise securities 88,920 5 (30 ) 88,895 Corporate debt securities 87,785 262 (8 ) 88,039 Commercial paper 102,151 61 — 102,212 $ 507,465 $ 335 $ (51 ) $ 507,749 December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Corporate debt securities $ 187,371 $ 39 $ (344 ) $ 187,066 Commercial paper 151,774 — (78 ) 151,696 $ 339,145 $ 39 $ (422 ) $ 338,762
Summary of Gross Unrealized Losses and Fair Value of Available-For-Sale Investments in Unrealized Loss Position	The following table presents gross unrealized losses and fair value for those available-for-sale investments that were in an unrealized loss position as of December 31, 2019 and December 31, 2018, aggregated by investment category and length of time that individual securities have been in a continuous loss position (in thousands): Less Than 12 Months 12 Months or Greater Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses December 31, 2019: U.S. Treasury notes $ 148,397 $ (13 ) $ — $ — $ 148,397 $ (13 ) Government sponsored enterprise securities 61,103 (30 ) — — 61,103 (30 ) Corporate debt securities 11,334 (8 ) — — 11,334 (8 ) Total $ 220,834 $ (51 ) $ — $ — $ 220,834 $ (51 ) December 31, 2018: Corporate debt securities $ 91,265 $ (130 ) $ 44,637 $ (214 ) $ 135,902 $ (344 ) Commercial paper 151,696 (78 ) — — 151,696 (78 ) Total $ 242,961 $ (208 ) $ 44,637 $ (214 ) $ 287,598 $ (422 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements of Cash Equivalents, Available-For-Sale Investment Securities and Equity Securities	The recurring fair value measurements of the Company’s cash equivalents, available-for-sale investment securities, and equity securities at December 31, 2019 and 2018 consisted of the following (in thousands): Fair Value Measurements at Reporting Date Using December 31, 2019 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Money market fund $ 98,084 $ 98,084 $ — $ — U.S. Treasury notes 228,603 228,603 — — Government sponsored enterprise securities 103,878 — 103,878 — Equity securities 2,307 2,307 — — Corporate debt securities 88,039 — 88,039 — Commercial paper 102,212 — 102,212 — $ 623,123 $ 328,994 $ 294,129 $ — Fair Value Measurements at Reporting Date Using December 31, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Money market fund $ 34,018 $ 34,018 $ — $ — Equity securities 1,309 1,309 — — Corporate debt securities 224,474 — 224,474 — Commercial paper 191,564 — 191,564 — $ 451,365 $ 35,327 $ 416,038 $ —

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	12 Months Ended
	Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Schedule of Inventory	Inventory consisted of the following (in thousands): December 31, 2019 2018 Finished goods $ 3,175 $ 1,110 Work in process 1,685 483 Raw material 1,481 2,477 $ 6,341 $ 4,070
Property and Equipment, Net	Property and equipment, net, consisted of the following (in thousands): December 31, 2019 2018 Computers and software $ 3,724 $ 3,745 Leasehold improvements 2,560 1,655 Furniture and fixtures 2,115 2,114 Machinery and equipment 113 — 8,512 7,514 Accumulated depreciation (5,332 ) (4,205 ) $ 3,180 $ 3,309
Schedule of Accrued Liabilities	Accrued liabilities consisted of the following (in thousands): December 31, 2019 2018 Accrued compensation and benefits $ 21,080 $ 17,028 Accrued research and development services 14,273 10,367 Accrued consulting and professional fees 13,691 19,325 Accrued sales allowances 11,326 5,849 Current portion of lease liabilities 3,434 — Accrued royalties 1,971 1,200 Other 1,829 2,629 $ 67,604 $ 56,398

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Summary of Company's Stock Option Activity	The following table summarizes the Company’s stock option activity during the year ended December 31, 2019: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (years) Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2018 19,868,781 $ 28.04 Granted 3,502,129 $ 28.22 Exercised (3,880,757 ) $ 24.73 Cancelled/forfeited (2,062,925 ) $ 29.10 Outstanding at December 31, 2019 17,427,228 $ 28.69 7.5 $ 247,336 Vested at December 31, 2019 8,622,679 $ 30.18 6.5 $ 109,605 Unvested at December 31, 2019 8,804,549 $ 27.23 8.5 $ 137,731 Exercisable at December 31, 2019 8,622,679 $ 30.18 6.5 $ 109,605
Summary of Company's RSU Activity	The following table summarizes the Company’s RSU activity during the year ended December 31, 2019: Number of Shares Weighted Average Grant Date Fair Value Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2018 373,706 $ 21.07 Granted 1,287,453 $ 25.22 Vested (84,409 ) $ 21.05 Cancelled/forfeited (131,587 ) $ 23.97 Outstanding at December 31, 2019 1,445,163 $ 24.50 $ 61,824 The weighted average per share fair value of RSUs granted during the years ended December 31, 2018 was approximately $21.07. As of December 31, 2019, total unrecognized compensation cost related to restricted stock options was approximately $22.7 million, and the weighted average period over which this cost is expected to be recognized is approximately 3.8 years.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Summary of Domestic and Foreign Pre-tax Loss	Domestic and foreign pre-tax loss is as follows (in thousands): Years Ended December 31, 2019 2018 2017 Domestic $ (123,411 ) $ (78,112 ) $ (45,249 ) Foreign (110,972 ) (165,824 ) (243,035 ) $ (234,383 ) $ (243,936 ) $ (288,284 )
Components of Deferred Tax Assets	The components of the deferred tax assets are as follows (in thousands): December 31, 2019 2018 Deferred tax assets NOL carryforwards 182,948 170,476 R&D credit carryforwards 48,069 32,984 Capitalized R&D 7,607 7,421 Stock-based compensation 45,440 45,492 Intangibles 59,783 — Charitable contributions 18,303 8,530 Lease liabilities 2,366 — Other 8,568 6,220 Total deferred tax assets 373,084 271,123 Valuation allowance (370,783 ) (271,123 ) Deferred tax liabilities Right-of-use assets (2,301 ) — Total deferred tax liabilities (2,301 ) — Total net deferred tax assets $ — $ —
Reconciliation of Income Taxes to Amount Computed by Applying Statutory Federal Income Tax Rate to Pretax Loss	A reconciliation of income taxes to the amount computed by applying the statutory federal income tax rate to the pretax loss is summarized as follows (in thousands): Years Ended December 31, 2019 2018 2017 Amounts computed at statutory federal rate $ (49,365 ) $ (51,226 ) $ (98,016 ) Stock-based compensation and other permanent differences 6,070 3,432 1,341 R&D credits (16,687 ) (7,941 ) (5,573 ) Change in valuation allowance 99,846 34,333 (28,230 ) State taxes (2,138 ) (1,017 ) (26 ) Contingencies 1,861 2,938 360 Foreign rate differential 20,413 20,896 61,480 Tax Cuts and Jobs Act — — 68,889 Switzerland Tax Reform (59,181 ) — — Other 57 (159 ) 894 Income tax expense $ 876 $ 1,256 $ 1,119
Unrecognized Tax Benefits	The following table provides a reconciliation of changes in unrecognized tax benefits (in thousands): Years Ended December 31, 2019 2018 2017 Balance at beginning of period $ 5,037 $ 1,933 $ 2,664 Additions related to current period tax positions 1,908 3,104 361 Impact of Tax Cuts and Jobs Act — — (1,092 ) Balance at end of period $ 6,945 $ 5,037 $ 1,933

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2019
Leases [Abstract]
Summary of Operating Lease Costs	The operating Years Ended December 31, 2019 2018 2017 Operating lease cost $ 5,155 $ 4,503 $ 3,828
Supplemental Cash Flow Information Related to the Company’s Leases	Supplemental cash flow information related to the Company’s leases were as follows (in thousands): Year Ended December 31, 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 4,841 Right-of-use assets obtained in exchange for operating lease obligations: 13,399
Summary of Balance Sheet Classification of Lease Liabilities	The balance sheet classification of the Company’s lease liabilities was as follows (in thousands): December 31, 2019 Operating lease liabilities Current portion included in accrued liabilities $ 3,434 Operating lease liabilities 6,361 Total operating lease liabilities $ 9,795
Summary of Maturities of Lease Liabilities	Maturities of lease liabilities were as follows (in thousands): Operating Leases Years ending December 31, 2020 $ 3,563 2021 2,660 2022 2,089 2023 1,192 2024 1,080 Thereafter 1,011 Total lease payments 11,595 Less: Imputed interest (1,800 ) Total operating lease liabilities $ 9,795
Estimated Annual Future Minimum Payments under Operating Leases and Other Long-term Contractual Obligation	Estimated annual future minimum payments related to the Company’s operating leases and other long-term contractual obligations were as follows at December 31, 2018 (in thousands): 2019 $ 4,770 2020 4,170 2021 6,906 2022 7,181 2023 6,568 Thereafter 38,683 $ 68,278

Selected Quarterly Financial _2

Selected Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data	Fiscal Year 2019 Quarters 1st 2nd 3rd 4th Total Revenues $ 62,959 $ 83,205 $ 94,586 $ 98,326 $ 339,076 Gross profit (1) $ 60,009 $ 80,247 $ 92,170 $ 95,306 $ 327,732 Net loss $ (85,304 ) $ (54,941 ) $ (41,978 ) $ (53,036 ) $ (235,259 ) Basic and diluted net loss per share (2) $ (0.59 ) $ (0.38 ) $ (0.29 ) $ (0.34 ) $ (1.60 ) Fiscal Year 2018 Quarters 1st 2nd 3rd 4th Total Revenues $ 48,868 $ 57,063 $ 58,305 $ 59,571 $ 223,807 Gross profit (1) $ 46,715 $ 53,501 $ 54,466 $ 56,748 $ 211,430 Net loss $ (54,296 ) $ (63,266 ) $ (62,138 ) $ (65,492 ) $ (245,192 ) Basic and diluted net loss per share (2) $ (0.44 ) $ (0.51 ) $ (0.50 ) $ (0.50 ) $ (1.94 ) ( 1 ) Determined by subtracting cost of product sales from product sales, net. ( 2 ) Net loss per common share, basic and diluted, are computed independently for each quarter and the full year based upon respective average shares outstanding. Therefore, the sum of the quarterly net loss per common share amounts may not equal the annual amounts reported.

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations [Abstract]
Cash and cash equivalents	$ 189,680	$ 134,758	$ 69,418
Restricted cash	4,787	4,826	2,475
Total cash, cash equivalents and restricted cash shown in the statements of cash flows	$ 194,467	$ 139,584	$ 71,893	$ 165,995

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Apr. 30, 2016USD ($)	Dec. 31, 2019USD ($)CustomerSegmentshares	Dec. 31, 2018USD ($)Customershares	Dec. 31, 2017USD ($)Customershares	Jan. 01, 2018USD ($)
Summary Of Significant Accounting Policy [Line Items]
Accounts receivable written off		$ 0	$ 100,000
Charge on finished goods inventory		1,100,000	2,700,000	$ 700,000
Impairment losses		0
One-time contingent regulatory milestone payment pursuant to agreement with Ipsen Group	$ 8,000,000
Finite-lived intangible assets, net	$ 8,000,000
Amortization of intangible assets		1,477,000	1,476,000	1,477,000
Estimated future amortization expense, 2020		1,500,000
Estimated future amortization expense, 2021		1,000,000
Advertising costs		38,300,000	39,800,000	$ 15,600,000
Advertising costs capitalized as prepaid expenses		0	0
Revenue recognition		$ (1,704,122,000)	$ (1,468,863,000)
Number of large customers | Customer		4	4	4
Antidilutive securities to purchase common stock | shares		19,516,000	20,824,000	18,526,000
Number of business segments | Segment		1
Tax rate		21.00%	21.00%	35.00%
Customer Concentration Risk | Revenue, Product and Service Benchmark | Four Customers
Summary Of Significant Accounting Policy [Line Items]
Concentration risk, percentage		77.00%	85.00%	89.00%
Customer Concentration Risk | Accounts Receivable | Four Customers
Summary Of Significant Accounting Policy [Line Items]
Concentration risk, percentage		75.00%	84.00%	87.00%
Topic 606
Summary Of Significant Accounting Policy [Line Items]
Cumulative-effect adjustment to retained earnings					$ 0
Increase to additional paid-in capital with corresponding increase to accumulated deficit					$ 0
Topic 606 | Difference effect of change - higher (lower)
Summary Of Significant Accounting Policy [Line Items]
Revenue recognition		$ 0
ASU 2016-09
Summary Of Significant Accounting Policy [Line Items]
Cumulative-effect adjustment to retained earnings		300,000
Increase in deferred tax assets to record unrecognized excess tax benefits		36,800,000
Increase to additional paid-in capital with corresponding increase to accumulated deficit		300,000
Increase in deferred tax assets to record excess tax benefit		$ 100,000

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Schedule of Estimated Useful Lives by Major Asset Category (Detail)	12 Months Ended
	Dec. 31, 2019
Machinery and Equipment | Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	5 years
Machinery and Equipment | Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	7 years
Computers and Software
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	3 years
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful lives	10 years

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Weighted-Average Assumptions Used to Estimate Fair Value of Employee Stock Options (Detail) - Stock Options	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assumptions Used To Determine Fair Value Options [Line Items]
Expected volatility	62.00%	71.00%	68.00%
Risk-free interest rate	2.00%	3.00%	2.00%
Expected dividend yield	0.00%	0.00%	0.00%
Expected life of options in years	5 years 8 months 12 days	5 years 8 months 12 days	5 years 9 months 18 days

Summary of Significant Accoun_8

Summary of Significant Accounting Policies - Weighted-Average Assumptions Used to Estimate Fair Value of Employee Stock Purchase Plan Rights (Detail) - Employee Stock Purchase Plan	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Employee Stock Purchase Plan [Line Items]
Expected volatility, minimum	62.00%	59.00%	44.00%
Expected volatility, maximum	86.00%	79.00%	62.00%
Risk-free interest rate, minimum	1.50%	2.10%	1.00%
Risk-free interest rate, maximum	2.40%	2.80%	1.70%
Expected dividend yield	0.00%	0.00%	0.00%
Minimum
Employee Stock Purchase Plan [Line Items]
Expected life in years	6 months	6 months	6 months
Maximum
Employee Stock Purchase Plan [Line Items]
Expected life in years	2 years	2 years	2 years

Summary of Significant Accoun_9

Summary of Significant Accounting Policies - Summary of Stock-based Compensation Expense Included in Statements of Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 82,265	$ 81,564	$ 75,532
Cost of product sales
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	2,936	3,863	3,690
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	32,533	32,038	26,485
Sales, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 46,796	$ 45,663	$ 45,357

Investments - Carrying Value an

Investments - Carrying Value and Amortized Cost of Company's Investments Summarized by Major Security Type (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Estimated Fair Value	$ 507,749	$ 338,762
Debt and equity securities, Amortized Cost	507,465	339,145
Debt and equity securities, Unrealized Gains	335	39
Debt and equity securities, Unrealized Losses	(51)	(422)
Debt and equity securities, Estimated Fair Value	507,749	338,762
U.S. Treasury notes
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	228,609
Debt securities, Unrealized Gains	7
Debt securities, Unrealized Losses	(13)
Debt securities, Estimated Fair Value	228,603
Government sponsored enterprise securities
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	88,920
Debt securities, Unrealized Gains	5
Debt securities, Unrealized Losses	(30)
Debt securities, Estimated Fair Value	88,895
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	87,785	187,371
Debt securities, Unrealized Gains	262	39
Debt securities, Unrealized Losses	(8)	(344)
Debt securities, Estimated Fair Value	88,039	187,066
Commercial paper
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	102,151	151,774
Debt securities, Unrealized Gains	61
Debt securities, Unrealized Losses		(78)
Debt securities, Estimated Fair Value	$ 102,212	$ 151,696

Investments - Additional Inform

Investments - Additional Information (Detail) $ in Millions	Dec. 31, 2019USD ($)Security	Dec. 31, 2018USD ($)Security
Investments Debt And Equity Securities [Abstract]
Available-for-sale, investment securities held with maturity dates more than one year and less than two years | $	$ 24.3	$ 31.8
Number of securities in unrealized loss position | Security	20	57

Investments - Summary of Gross

Investments - Summary of Gross Unrealized Losses and Fair Value of Available-For-Sale Investments in Unrealized Loss Position (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	$ 220,834	$ 242,961
Less Than 12 Months, Unrealized Losses	(51)	(208)
12 Months or Greater, Estimated Fair Value		44,637
12 Months or Greater, Unrealized Losses		(214)
Total, Estimated Fair Value	220,834	287,598
Total, Unrealized Losses	(51)	(422)
U.S. Treasury notes
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	148,397
Less Than 12 Months, Unrealized Losses	(13)
Total, Estimated Fair Value	148,397
Total, Unrealized Losses	(13)
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	11,334	91,265
Less Than 12 Months, Unrealized Losses	(8)	(130)
12 Months or Greater, Estimated Fair Value		44,637
12 Months or Greater, Unrealized Losses		(214)
Total, Estimated Fair Value	11,334	135,902
Total, Unrealized Losses	(8)	(344)
Government sponsored enterprise securities
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	61,103
Less Than 12 Months, Unrealized Losses	(30)
Total, Estimated Fair Value	61,103
Total, Unrealized Losses	$ (30)
Commercial paper
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value		151,696
Less Than 12 Months, Unrealized Losses		(78)
Total, Estimated Fair Value		151,696
Total, Unrealized Losses		$ (78)

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Measurements of Cash Equivalents, Available-For-Sale Investment Securities and Equity Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	$ 623,123	$ 451,365
Money market fund
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	98,084	34,018
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	328,994	35,327
Quoted Prices in Active Markets for Identical Assets (Level 1) | Money market fund
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	98,084	34,018
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	294,129	416,038
U.S. Treasury notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	228,603
U.S. Treasury notes | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	228,603
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	2,307	1,309
Equity securities | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	2,307	1,309
Government sponsored enterprise securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	103,878
Government sponsored enterprise securities | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	103,878
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	88,039	224,474
Corporate debt securities | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	88,039	224,474
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	102,212	191,564
Commercial paper | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	$ 102,212	$ 191,564

Balance Sheet Details - Schedul

Balance Sheet Details - Schedule of Inventory (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Finished goods	$ 3,175	$ 1,110
Work in process	1,685	483
Raw material	1,481	2,477
Inventory	$ 6,341	$ 4,070

Balance Sheet Details - Propert

Balance Sheet Details - Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 8,512	$ 7,514
Accumulated depreciation	(5,332)	(4,205)
Property and equipment, net	3,180	3,309
Machinery and Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	113
Computers and Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,724	3,745
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,560	1,655
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,115	$ 2,114

Balance Sheet Details - Additio

Balance Sheet Details - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Depreciation of property and equipment	$ 1,289	$ 1,529	$ 1,236
Removal of fully depreciated property, machinery and equipment	$ 200	$ 1,600	$ 400

Balance Sheet Details - Sched_2

Balance Sheet Details - Schedule of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Payables And Accruals [Abstract]
Accrued compensation and benefits	$ 21,080	$ 17,028
Accrued research and development services	14,273	10,367
Accrued consulting and professional fees	13,691	19,325
Accrued sales allowances	11,326	5,849
Current portion of lease liabilities	3,434
Accrued royalties	1,971	1,200
Other	1,829	2,629
Accrued liabilities	$ 67,604	$ 56,398

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	1 Months Ended										12 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Nov. 30, 2018	Jun. 30, 2018	Jun. 30, 2017	Aug. 31, 2016	Jun. 30, 2016	Jan. 31, 2016	Jun. 30, 2015	Dec. 31, 2012	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2010
Class of Stock [Line Items]
Net proceeds from sale of common stock	$ 271,500,000		$ 298,500,000			$ 215,900,000		$ 281,600,000			$ 371,847,000	$ 306,647,000	$ 31,188,000
Issuance of common stock in public offering, net of issuance costs (in shares)	7,187,500		18,602,941			6,969,696		10,344,827		19,000,000
Common stock, par value											$ 0.0001	$ 0.0001
Value of shares purchased by Baker Entities in public offerings											$ 15,000	$ 14,000
Proceed from sale of stock and warrants										$ 80,500,000
Common stock sale price per share										$ 4.43
Warrants issued										500,000
Warrants issuance price per share										$ 4.42
Warrant exercise price										$ 0.01
Issuance of warrant value										$ 2,200,000
Warrants outstanding										500,000	493,145
Description of warrant											Per their terms, the warrants to purchase 500,000 shares of common stock, of which 493,145 remained outstanding at December 31, 2019, may not be exercised if the holder’s ownership of the Company’s common stock would exceed 19.99 percent following such exercise.
Options vesting period											4 years
Closing market price of Common stock											$ 42.78
Aggregate intrinsic value of stock options exercised											$ 56,600,000	$ 11,200,000	$ 24,400,000
Cash received from options exercised											$ 96,000,000
Weighted average per share fair value of options granted											$ 15.97	$ 12.14	$ 21.11
Unrecognized compensation costs											$ 119,300,000
Weighted average period cost expected to be recognized											2 years 9 months 18 days
Issuance of common stock pursuant to employee stock purchase plan											$ 4,411,000	$ 3,682,000	$ 4,522,000
Stock Options | Equity Incentive Plan 2010
Class of Stock [Line Items]
Exercise price of Options as percentage of fair market value														100.00%
Options maximum expiration term														10 years
Options vesting period														4 years
Number of common stock authorized for issuance											31,254,090
Common stock available for grants											12,381,699
Common stock reserved for issuance under stock purchase plan		8,300,000		6,700,000	5,500,000		3,000,000		5,000,000
Stock Options | Equity Incentive Plan 2004
Class of Stock [Line Items]
Exercise price of Options as percentage of fair market value											100.00%
Options vesting period											4 years
Number of common stock authorized for issuance		600,000
Number of periods additional number of shares could be added to shares authorized for issuance											10 years
Restricted Stock Units
Class of Stock [Line Items]
Unrecognized compensation costs											$ 22,700,000
Weighted average period cost expected to be recognized											3 years 9 months 18 days
Weighted average grant date fair value, Granted											$ 25.22	$ 21.07
Employee Stock Purchase Plan
Class of Stock [Line Items]
Number of common stock authorized for issuance											2,525,000
Common stock reserved for issuance under stock purchase plan							400,000
Term of ESPP Evergreen Provision											10 years
Common stock remained available for issuance pursuant to the Purchase Plan											485,254
Eligible employees percentage of earnings withheld to purchase shares under purchase plan											15.00%
Purchase price of common stock as percentage of market value											85.00%
Issuance of common stock pursuant to employee stock purchase plan											269,037	233,720	192,402
Average per share price of stock issued under purchase plan											$ 16.41	$ 15.75	$ 23.50
Weighted average per share fair value of purchase rights granted											$ 14.24	$ 8.25	$ 11.44
Issuance of common stock pursuant to employee stock purchase plan											$ 4,400,000	$ 3,700,000	$ 4,500,000
Registration Rights Agreement
Class of Stock [Line Items]
Common stock, par value								$ 0.0001
Expiration period								10 years
Maximum amount of expense agreed to bear under the agreement								$ 50,000
Registration Rights Agreement | Baker Brothers Life Sciences L.P.
Class of Stock [Line Items]
Value of shares purchased by Baker Entities in public offerings	$ 62,500,000		$ 200,000,000			$ 43,000,000		$ 75,000,000
Option To Purchase Additional Shares
Class of Stock [Line Items]
Issuance of common stock in public offering, net of issuance costs (in shares)	937,500		2,426,470			909,090

Summary of Company's Stock Opti

Summary of Company's Stock Option Activity (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)$ / sharesshares
Number of Shares
Options Outstanding, Beginning Balance | shares	19,868,781
Granted | shares	3,502,129
Exercised | shares	(3,880,757)
Cancelled/forfeited | shares	(2,062,925)
Options Outstanding, Ending Balance | shares	17,427,228
Vested at December 31, 2019 | shares	8,622,679
Unvested at December 31, 2019 | shares	8,804,549
Exercisable | shares	8,622,679
Weighted Average Exercise Prices
Weighted Average Exercise Prices, Beginning Balance | $ / shares	$ 28.04
Weighted Average Exercise Prices, granted | $ / shares	28.22
Weighted Average Exercise Prices, exercised | $ / shares	24.73
Weighted Average Exercise Prices, Cancelled/forfeited | $ / shares	29.10
Weighted Average Exercise Prices, Ending Balance | $ / shares	28.69
Weighted Average Exercise Prices, Vested | $ / shares	30.18
Weighted Average Exercise Prices, Unvested | $ / shares	27.23
Weighted Average Exercise Prices, Exercisable | $ / shares	$ 30.18
Weighted average remaining contractual term, Outstanding	7 years 6 months
Weighted average remaining contractual term, Vested	6 years 6 months
Weighted average remaining contractual term, Unvested	8 years 6 months
Weighted average remaining contractual term, Exercisable	6 years 6 months
Aggregate Intrinsic Value, Outstanding | $	$ 247,336
Aggregate Intrinsic Value, Vested | $	109,605
Aggregate Intrinsic Value, Unvested | $	137,731
Aggregate Intrinsic Value, Exercisable | $	$ 109,605

Summary of Company's RSU Activi

Summary of Company's RSU Activity (Detail) - Restricted Stock Units - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Number of Shares
Outstanding, Begining Balance	373,706
Granted	1,287,453
Vested	(84,409)
Cancelled/forfeited	(131,587)
Outstanding, Ending Balance	1,445,163	373,706
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value , Begining Balance	$ 21.07
Weighted Average Grant Date Fair Value, Granted	25.22	$ 21.07
Weighted Average Grant Date Fair Value, Vested	21.05
Weighted Average Grant Date Fair Value, Cancelled/forfeited	23.97
Weighted Average Grant Date Fair Value, Ending Balance	$ 24.50	$ 21.07
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Outstanding	$ 61,824

401 (k) Plan - Additional Infor

401 (k) Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Compensation And Retirement Disclosure [Abstract]
Maximum contribution by employee, percentage of pretax earnings	60.00%
Percentage of company's matching contribution with respect to each participant's contribution	100.00%
Company matching contributions to maximum employees eligible compensation	5.00%
Company contributions to 401 (k) plan	$ 4.3	$ 3.6	$ 3.3

Income Taxes - Summary of Domes

Income Taxes - Summary of Domestic and Foreign Pre-tax Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest [Abstract]
Domestic pre-tax income (loss)	$ (123,411)	$ (78,112)	$ (45,249)
Foreign pre-tax income (loss)	(110,972)	(165,824)	(243,035)
Total pre-tax income (loss)	$ (234,383)	$ (243,936)	$ (288,284)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2015
Income Tax [Line Items]
State income tax provision	$ 900,000	$ 1,300,000	$ 1,100,000
Charitable contribution carryforwards	18,303,000	$ 8,530,000
Federal R&D credit carryforwards	40,400,000
Increase in valuation allowance of deferred tax assets	$ 99,700,000
Tax rate	21.00%	21.00%	35.00%
Deferred tax asset , Switzerland tax reform	$ 57,000,000
Unrecognized tax reserves recorded during period	1,908,000	$ 3,104,000	$ 361,000
Interest and/or penalties accrued	0	0
Tax cuts and jobs act provisional adjustment			1,100,000
Interest and/or penalties	0	$ 0	$ 0
Federal
Income Tax [Line Items]
Operating loss carryforwards	426,100,000
Federal | Expiring in 2025
Income Tax [Line Items]
Operating loss carryforwards	6,900,000
Federal | Expiring in 2021
Income Tax [Line Items]
Charitable contribution carryforwards				$ 75,800
State
Income Tax [Line Items]
Operating loss carryforwards	$ 363,200,000
Remaining net operating loss carryforward, expiration year	2026
Research and development credit carryforwards with no expiration date	$ 13,500,000
State | Expiring in 2024
Income Tax [Line Items]
Net operating loss carryforwards with no expiration date	1,500,000
State | Expiring in 2025 | Maximum
Income Tax [Line Items]
Operating loss carryforwards	100,000
State | Expiring in 2021
Income Tax [Line Items]
Charitable contribution carryforwards				$ 75,800
Foreign
Income Tax [Line Items]
Operating loss carryforwards	$ 1,004,200,000
Remaining net operating loss carryforward, expiration year	2026
Net operating loss carryforwards with no expiration date	$ 3,400,000
Foreign | Operating Loss Carryforwards Expiring 2022
Income Tax [Line Items]
Operating loss carryforwards	1,000,900,000
Expire in 2020
Income Tax [Line Items]
Federal R&D credit carryforwards	$ 200,000

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets
NOL carryforwards	$ 182,948	$ 170,476
R&D credit carryforwards	48,069	32,984
Capitalized R&D	7,607	7,421
Stock-based compensation	45,440	45,492
Intangibles	59,783
Charitable contribution carryforwards	18,303	8,530
Lease liabilities	2,366
Other	8,568	6,220
Total deferred tax assets	373,084	271,123
Valuation allowance	(370,783)	$ (271,123)
Deferred tax liabilities
Right-of-use assets	(2,301)
Total deferred tax liabilities	$ (2,301)

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Income Taxes to Amount Computed by Applying Statutory Federal Income Tax Rate to Pretax Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Amounts computed at statutory federal rate	$ (49,365)	$ (51,226)	$ (98,016)
Stock-based compensation and other permanent differences	6,070	3,432	1,341
R&D credits	(16,687)	(7,941)	(5,573)
Change in valuation allowance	99,846	34,333	(28,230)
State taxes	(2,138)	(1,017)	(26)
Contingencies	1,861	2,938	360
Foreign rate differential	20,413	20,896	61,480
Tax Cuts and Jobs Act			68,889
Switzerland Tax Reform	(59,181)
Other	57	(159)	894
Income tax expense	$ 876	$ 1,256	$ 1,119

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Balance at beginning of period	$ 5,037	$ 1,933	$ 2,664
Additions related to current period tax positions	1,908	3,104	361
Impact of Tax Cuts and Jobs Act			(1,092)
Balance at end of period	$ 6,945	$ 5,037	$ 1,933

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	1 Months Ended		12 Months Ended
	Aug. 31, 2018	May 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Other Commitments [Line Items]
Gain (loss) on strategic investments			$ 997,000	$ (1,840,000)
Restricted cash			4,787,000	4,826,000	$ 2,475,000
Corporate Credit Card Program | Letter of Credit
Other Commitments [Line Items]
Restricted cash						$ 2,000,000
Corporate Fleet Program | Letter of Credit
Other Commitments [Line Items]
Restricted cash			400,000
Other assets
Other Commitments [Line Items]
Aggregate carrying amount of strategic equity investment			2,300,000	1,300,000
Other expense
Other Commitments [Line Items]
Gain (loss) on strategic investments			$ 1,000,000	(1,800,000)
Exclusivity Deed | Neuren
Other Commitments [Line Items]
Aggregate carrying amount of strategic equity investment		$ 3,100,000
Shares subscribed		1,330,000
Exclusivity Deed | Neuren | Sales, general and administrative
Other Commitments [Line Items]
Payments for exclusive right		$ 900,000
License Agreements | Neuren | North America
Other Commitments [Line Items]
Upfront payment	$ 10,000,000
License Agreements | Neuren | Research and development | North America
Other Commitments [Line Items]
Upfront payment				$ 10,000,000
Maximum
Other Commitments [Line Items]
Percentage of royalty payments obligation on net product sales			2.00%
Maximum | License Agreements | Neuren | North America
Other Commitments [Line Items]
Milestone payments payable	$ 455,000,000

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2015
Lessee Lease Description [Line Items]
Operating lease, expiration year	2031-02
Operating lease liabilities	$ 9,795,000	$ 0
Operating lease right-of-use assets	$ 9,524,000	0
Operating lease, description	The Company leases facilities and certain equipment under noncancelable operating leases with remaining lease terms of 0.3 year to 6.1 years, one of which includes an option to extend the lease for one five-year term.
Operating lease, option to extend	true
Operating lease, options to extend	one of which includes an option to extend the lease for one five-year term.
Operating lease, renewal term	5 years
weighted average remaining lease term	4 years 8 months 12 days
Weighted average discount rate	8.00%
Restricted cash	$ 4,787,000	$ 4,826,000	$ 2,475,000
Corporate Office Space Lease Agreement
Lessee Lease Description [Line Items]
Operating leases arrangement term		10 years 9 months
Corporate Office Space Lease Agreement | Letter of Credit
Lessee Lease Description [Line Items]
Restricted cash	$ 2,200,000
CALIFORNIA | Corporate Office Space Lease Agreement
Lessee Lease Description [Line Items]
Minimum lease payment amount		$ 53,700,000
Lease commencement period	third quarter of 2020
Minimum
Lessee Lease Description [Line Items]
Operating lease remaining lease term	3 months 18 days
Maximum
Lessee Lease Description [Line Items]
Operating lease remaining lease term	6 years 1 month 6 days
Vehicles
Lessee Lease Description [Line Items]
Operating leases arrangement term				36 months
Vehicles | Minimum
Lessee Lease Description [Line Items]
Operating leases arrangement term				12 months
Vehicles | Maximum
Lessee Lease Description [Line Items]
Operating leases arrangement term				50 months

Leases - Summary of Operating L

Leases - Summary of Operating Lease Costs (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Lease Cost [Abstract]
Operating lease cost	$ 5,155	$ 4,503	$ 3,828

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information Related to the Company's Leases (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 4,841
Right-of-use assets obtained in exchange for operating lease obligations:	$ 13,399

Leases - Summary of Balance She

Leases - Summary of Balance Sheet Classification of Lease Liabilities (Detail) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Operating lease liabilities
Current portion of lease liabilities	$ 3,434,000
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesCurrent
Operating lease liabilities	$ 6,361,000
Total operating lease liabilities	$ 9,795,000	$ 0

Leases - Summary of Maturities

Leases - Summary of Maturities of Lease Liabilities (Detail) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Operating Lease Liabilities [Abstract]
2020	$ 3,563,000
2021	2,660,000
2022	2,089,000
2023	1,192,000
2024	1,080,000
Thereafter	1,011,000
Total lease payments	11,595,000
Less:
Imputed interest	(1,800,000)
Total operating lease liabilities	$ 9,795,000	$ 0

Leases - Estimated Annual Futur

Leases - Estimated Annual Future Minimum Payments under Operating Leases and Other Long-term Contractual Obligation (Detail) $ in Thousands	Dec. 31, 2018USD ($)
Leases [Abstract]
2019	$ 4,770
2020	4,170
2021	6,906
2022	7,181
2023	6,568
Thereafter	38,683
Operating Leases, Future Minimum Payments Due, Total	$ 68,278

Selected Quarterly Financial _3

Selected Quarterly Financial Data (Unaudited) - Selected Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended																12 Months Ended
		Dec. 31, 2019		Sep. 30, 2019		Jun. 30, 2019		Mar. 31, 2019		Dec. 31, 2018		Sep. 30, 2018		Jun. 30, 2018		Mar. 31, 2018		Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Revenues		$ 98,326		$ 94,586		$ 83,205		$ 62,959		$ 59,571		$ 58,305		$ 57,063		$ 48,868		$ 339,076		$ 223,807
Gross profit	[1]	95,306		92,170		80,247		60,009		56,748		54,466		53,501		46,715		327,732		211,430
Net loss		$ (53,036)		$ (41,978)		$ (54,941)		$ (85,304)		$ (65,492)		$ (62,138)		$ (63,266)		$ (54,296)		$ (235,259)		$ (245,192)		$ (289,403)
Basic and diluted net loss per share		$ (0.34)	[2]	$ (0.29)	[2]	$ (0.38)	[2]	$ (0.59)	[2]	$ (0.50)	[2]	$ (0.50)	[2]	$ (0.51)	[2]	$ (0.44)	[2]	$ (1.60)	[2]	$ (1.94)	[2]	$ (2.36)
[1]	Determined by subtracting cost of product sales from product sales, net.
[2]	Net loss per common share, basic and diluted, are computed independently for each quarter and the full year based upon respective average shares outstanding. Therefore, the sum of the quarterly net loss per common share amounts may not equal the annual amounts reported.

Subsequent Event - Additional I

Subsequent Event - Additional Information (Detail) - Corporate Office Space Lease Agreement $ in Millions	12 Months Ended
	Dec. 31, 2019	Feb. 24, 2020USD ($)ft²	Dec. 31, 2018USD ($)
Subsequent Event [Line Items]
Operating leases arrangement term			10 years 9 months
CALIFORNIA
Subsequent Event [Line Items]
Minimum lease payment amount			$ 53.7
Lease commencement period	third quarter of 2020
Subsequent Event
Subsequent Event [Line Items]
Operating leases arrangement term		10 years 7 months
Subsequent Event | CALIFORNIA
Subsequent Event [Line Items]
Office space leases in square feet | ft²		31,608
Minimum lease payment amount		$ 25.3

SCHEDULE II - Valuation and Q_2

SCHEDULE II - Valuation and Qualifying Accounts (Detail) - Allowance for Distribution Fees, Discounts and Chargebacks - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 1,840	$ 246	$ 201
Additions, Provision Related to Current Period Sales	33,827	24,613	12,837
Deductions, Actual Distribution Fees, Discounts and Chargebacks Related to Current Period Sales	(31,251)	(22,773)	(12,591)
Deductions, Actual Distribution Fees, Discounts and Chargebacks Related to Prior Period Sales	(1,840)	(246)	(201)
Balance at End of Period	$ 2,576	$ 1,840	$ 246