ACADIA Pharmaceuticals (ACAD) 10-K24 Feb 212020 FY Annual reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2020	Feb. 10, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2020
Document Fiscal Year Focus	2020
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		160,047,470
Entity Public Float			$ 4,600,000,000
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	12830 El Camino Real
Entity Address, Address Line Two	Suite 400
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 30, 2021 are incorporated by reference into Part III of this report.
ICFR Auditor Attestation Flag	true

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets
Cash and cash equivalents	$ 326,028	$ 189,680
Investment securities, available-for-sale	305,930	507,749
Accounts receivable, net	48,247	35,781
Interest and other receivables	2,035	2,093
Inventory	9,682	6,341
Prepaid expenses	25,694	18,606
Total current assets	717,616	760,250
Property and equipment, net	9,161	3,180
Operating lease right-of-use assets	47,283	9,524
Intangible assets, net	1,108	2,585
Restricted cash	5,770	4,787
Other assets	1,678	2,857
Total assets	782,616	783,183
Liabilities and stockholders’ equity
Accounts payable	8,493	7,222
Accrued liabilities	97,474	67,604
Total current liabilities	105,967	74,826
Operating lease liabilities	44,460	6,361
Other long-term liabilities	5,180	2,861
Total liabilities	155,607	84,048
Commitments and contingencies (Note 9)
Stockholders’ equity:
Preferred stock, $0.0001 par value; 5,000,000 shares authorized at December 31, 2020 and 2019; no shares issued and outstanding at December 31, 2020 and 2019
Common stock, $0.0001 par value; 225,000,000 shares authorized at December 31, 2020 and 2019; 159,637,771 shares and 155,275,300 shares issued and outstanding at December 31, 2020 and 2019, respectively	16	15
Additional paid-in capital	2,612,663	2,402,945
Accumulated deficit	(1,985,706)	(1,704,122)
Accumulated other comprehensive income	36	297
Total stockholders’ equity	627,009	699,135
Total liabilities and stockholders’ equity	$ 782,616	$ 783,183

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
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	159,637,771	155,275,300
Common stock, shares outstanding	159,637,771	155,275,300

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2018
Revenues
Type of Revenue [Extensible List]	us-gaap:ProductMember		us-gaap:ProductMember		us-gaap:ProductMember
Total revenues	$ 441,755		$ 339,076		$ 223,807
Operating expenses
Type of Cost, Good or Service [Extensible List]	us-gaap:ProductMember		us-gaap:ProductMember		us-gaap:ProductMember
Cost of product sales	$ 10,211		$ 11,344		$ 12,377
License fees and royalties	10,339		8,254		5,953
Research and development	319,130		240,385		187,163
Selling, general and administrative	388,661		325,638		265,758
Total operating expenses	728,341		585,621		471,251
Loss from operations	(286,586)		(246,545)		(247,444)
Interest income, net	6,610		11,165		5,348
Other (expense) income	(997)		997		(1,840)
Loss before income taxes	(280,973)		(234,383)		(243,936)
Income tax expense	611		876		1,256
Net loss	$ (281,584)		$ (235,259)		$ (245,192)
Net loss per common share, basic and diluted	$ (1.79)	[1]	$ (1.60)	[1]	$ (1.94)
Weighted average common shares outstanding, basic and diluted	157,331		147,199		126,583

[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, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (281,584)	$ (235,259)	$ (245,192)
Other comprehensive income (loss):
Unrealized (loss) gain on investment securities	(253)	667	24
Foreign currency translation adjustments	(8)	2	3
Comprehensive loss	$ (281,845)	$ (234,590)	$ (245,165)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities
Net loss	$ (281,584)	$ (235,259)	$ (245,192)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	84,422	82,265	81,564
Amortization of premiums and accretion of discounts on investment securities	1,470	(3,613)	(578)
Amortization of intangible assets	1,477	1,477	1,476
Loss (gain) on strategic investment	997	(997)	1,840
Depreciation	1,455	1,289	1,529
Loss on disposal of assets	281	3	88
Non-cash in-process research and development	44,280
Changes in operating assets and liabilities:
Accounts receivable, net	(12,466)	(9,691)	(8,747)
Interest and other receivables	58	(394)	(612)
Inventory	(3,320)	(1,737)	1,926
Prepaid expenses and other current assets	(7,088)	2,121	(12,270)
Operating lease right-of-use assets	4,280	3,875
Other assets	182	39	(236)
Accounts payable	1,271	4,055	(5,619)
Accrued liabilities	27,569	6,458	15,994
Operating lease liabilities	(1,769)	(2,518)
Long-term liabilities	2,319	1,497	1,367
Net cash used in operating activities	(136,166)	(151,130)	(167,470)
Cash flows from investing activities
Purchases of investment securities	(339,908)	(578,634)	(327,914)
Maturities of investment securities	540,004	413,927	261,678
Purchases of strategic investments			(3,149)
Net purchases of property and equipment	(7,587)	(1,129)	(2,104)
Net cash provided by (used in) investing activities	192,509	(165,836)	(71,489)
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs	80,996	371,847	306,647
Net cash provided by financing activities	80,996	371,847	306,647
Effect of exchange rate changes on cash	(8)	2	3
Net increase in cash, cash equivalents and restricted cash	137,331	54,883	67,691
Cash, cash equivalents and restricted cash
Beginning of period	194,467	139,584	71,893
End of period	331,798	194,467	139,584
Supplemental disclosure of cash flow information:
Cash paid for income taxes	1,113	1,597	1,261
Supplemental disclosure of noncash information:
Property and equipment purchases in accounts payable and accrued liabilities	130	$ 34	$ 160
Value of common stock issued in connection with asset acquisition	$ 44,280

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, 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	4,428		4,428
Issuance of common stock from exercise of stock options (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	27				27
Ending balance at Dec. 31, 2018	479,079	$ 14	1,948,300	(1,468,863)	(372)
Ending 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 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	669				669
Ending balance at Dec. 31, 2019	699,135	$ 15	2,402,945	(1,704,122)	297
Ending balance (in shares) at Dec. 31, 2019		155,275,300
Issuance of common stock in connection with asset acquisition	$ 44,280		44,280
Issuance of common stock in connection with asset acquisition, Shares		1,156,626
Issuance of common stock from exercise of stock options (in shares)	2,571,633
Issuance of common stock from exercise of stock options and units	$ 73,834	$ 1	73,833
Issuance of common stock from exercise of stock options and units (in shares)		2,827,586
Issuance of common stock pursuant to employee stock purchase plan	7,162		7,162
Issuance of common stock pursuant to employee stock purchase plan (in shares)		378,259
Net loss	(281,584)			(281,584)
Stock-based compensation	84,443		84,443
Other comprehensive income	(261)				(261)
Ending balance at Dec. 31, 2020	$ 627,009	$ 16	$ 2,612,663	$ (1,985,706)	$ 36
Ending balance (in shares) at Dec. 31, 2020		159,637,771

Organization and Business

Organization and Business	12 Months Ended
Organization and Business	Dec. 31, 2020
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
Summary of Significant Accounting Policies	Dec. 31, 2020
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, 2020 Twelve Months Ended December 31, 2019 Beginning of period End of period Beginning of period End of period Cash and cash equivalents $ 189,680 $ 326,028 $ 134,758 $ 189,680 Restricted cash 4,787 5,770 4,826 4,787 Total cash, cash equivalents and restricted cash shown in the statements of cash flows $ 194,467 $ 331,798 $ 139,584 $ 194,467 Investment Securities Currently, all of the Company’s investment securities are debt 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 credit losses. Allowances for distribution fees, prompt payment discounts and chargebacks are based on contractual terms. The Company adopted Financial Accounting Standards Board (FASB) Accounting Standards Codification 326-20, Financial Instruments – Credit Losses Although the Company has not historically experienced significant credit losses, the Company’s exposure may increase due to uncertainties associated with the global economic recession and other disruptions resulting from the COVID-19 pandemic. Inventory Inventory is stated at the lower of cost or net realizable value under the first-in, first-out method (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, 2020, 2019 and 2018, the Company recorded charges of $0.4 million, $1.1 million and $2.7 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, 2020, 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, 2020, 2019 and 2018. As of December 31, 2020, estimated future amortization expense related to the Company’s intangible asset was $1.1 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. Acquisitions The Company accounts for 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 $51.1 million, $38.3 million and $39.8 million in advertising costs during the years ended December 31, 2020, 2019 and 2018, respectively, related to NUPLAZID. No advertising costs were capitalized as prepaid expenses at December 31, 2020 or 2019. Revenue Recognition Product Sales, Net The Company accounts for contracts with its customers in accordance with Revenue from Contracts with Customers (Topic 606), 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 still estimated to be incurred . 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 upfront consideration and transaction costs associated with acquired in-process research and development are also included in the research and development 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, it records those amounts as prepaid expenses on its 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, 2020, the Company’s four largest customers represented approximately 74% of the Company’s product revenue and 75% of the Company’s accounts receivable balance at December 31, 2020. 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. 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, 2020 2019 2018 Stock Options: Expected volatility 63 % 62 % 71 % Risk-free interest rate 1 % 2 % 3 % Expected dividend yield 0 % 0 % 0 % Expected life of options in years 5.5 5.7 5.7 Years Ended December 31, 2020 2019 2018 Employee Stock Purchase Plan: Expected volatility 50%-76% 62%-86% 59%-79% Risk-free interest rate 0.1%-0.2% 1.5%-2.4% 2.1%-2.8% 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 over a four-year period. The fair value of RSUs expected to vest are recognized and amortized on a straight-line basis over the requisite service period, which is generally the vesting period. The fair value of performance-based stock units (PSUs) is estimated based on the closing market price of the Company’s common stock on the date of grant. PSUs vest upon the achievement of certain pre-defined company-specific performance-based criteria. Expense related to these PSUs is generally recognized ratably over the expected performance period once the pre-defined performance-based criteria for vesting becomes probable. 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, 2020 2019 2018 Cost of product sales $ 2,632 $ 2,936 $ 3,863 Research and development 31,314 32,533 32,038 Sales, general and administrative 50,476 46,796 45,663 $ 84,422 $ 82,265 $ 81,564 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 to be 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, 2020, 2019 and 2018, options, employee stock purchase rights, RSUs, PSUs, and warrants covering a total of approximately 19,331,000 shares, 19,516,000 shares and 20,824,000 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, 2020, 2019 and 2018 were generated from customers in the United States. Recently Issued Accounting Standards In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments 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 December 2019, the FASB issued ASU 2019-12 Income Taxes (Topic 740), Simplifying the Accounting for Income Taxes

Investments

Investments	12 Months Ended
Investments	Dec. 31, 2020
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, 2020 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value U.S. Treasury notes $ 205,111 $ 6 $ (27 ) $ 205,090 Government sponsored enterprise securities 10,004 — (5 ) 9,999 Corporate debt securities 52,341 47 — * 52,388 Commercial paper 38,443 21 (11 ) 38,453 $ 305,899 $ 74 $ (43 ) $ 305,930 _______________________ * Unrealized loss was less than $500. 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 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, 2020, all of the Company’s available-for-sale investment securities have contractual maturity dates of less than one year. At December 31, 2020 and 2019, the Company had 24 and 20 securities, respectively, 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, 2020 and December 31, 2019, 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, 2020: U.S. Treasury notes $ 129,631 $ (27 ) $ — $ — $ 129,631 $ (27 ) Government sponsored enterprise securities 10,004 (5 ) — — 10,004 (5 ) Corporate debt securities 6,252 — * — — 6,252 — * Commercial paper 23,466 (11 ) 23,466 (11 ) Total $ 169,353 $ (43 ) $ — $ — $ 169,353 $ (43 ) 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 ) _______________________ * Unrealized loss was less than $500. As described further in Note 2, Recently Issued Accounting Standards the Company adopted FASB Accounting Standards Codification 326-30, Financial Instruments – Credit Losses (ASC 326-30) as of January 1, 2020. ASC 326-30 requires the Company to determine whether a decline in the fair value below the amortized cost basis of available-for-sale securities is due to credit-related factors. At each reporting date, the Company performs an evaluation of impairment to determine if any unrealized losses are the result of credit losses. Impairment is assessed at the individual security level. Factors considered in determining whether a loss resulted from a credit loss or other factors include the Company’s intent and ability to hold the investment until the recovery of its amortized cost basis, the extent to which the fair value is less than the amortized cost basis, the length of time and extent to which fair value has been less than the cost basis, the financial condition of the issuer, any historical failure of the issuer to make scheduled interest or principal payments, any changes to the rating of the security by a rating agency, any adverse legal or regulatory events affecting the issuer or issuer’s industry, any significant deterioration in economic conditions. The does not intend to sell the investment in unrealized loss position and it is unlikely that the Company will be required to sell the investment before the recovery of its amortized cost basis. Based on its evaluation, the Company determined its year-to-date credit losses related to its available-for-sale securities were immaterial at December 31, 2020. Although the Company has not historically experienced significant losses on its investments, the Company’s exposure may increase due to uncertainties associated with the global economic recession and other disruptions resulting from the COVID-19 pandemic.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
Fair Value Measurements	Dec. 31, 2020
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 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, 2020 and 2019, 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, 2020 and 2019 consisted of the following (in thousands): Fair Value Measurements at Reporting Date Using December 31, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Money market fund $ 300,339 $ 300,339 $ — $ — U.S. Treasury notes 230,088 230,088 — — Government sponsored enterprise securities 9,999 — 9,999 — Equity securities 1,309 1,309 — — Corporate debt securities 52,388 — 52,388 — Commercial paper 38,453 — 38,453 — $ 632,576 $ 531,736 $ 100,840 $ — 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 $ —

Balance Sheet Details

Balance Sheet Details	12 Months Ended
Balance Sheet Details	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Balance Sheet Details	5. Balance Sheet Details Inventory consisted of the following (in thousands): December 31, 2020 2019 Finished goods $ 1,453 $ 3,175 Work in process 6,367 1,685 Raw material 1,862 1,481 $ 9,682 $ 6,341 Property and equipment, net, consisted of the following (in thousands): December 31, 2020 2019 Computers and software $ 5,315 $ 3,724 Leasehold improvements $ 4,033 $ 2,560 Furniture and fixtures $ 3,648 $ 2,115 Machinery and equipment $ 113 $ 113 $ 13,109 $ 8,512 Accumulated depreciation $ (3,948 ) $ (5,332 ) $ 9,161 $ 3,180 Depreciation of property and equipment was $1.5 million, $1.3 million, and $1.5 million for the years ended December 31, 2020, 2019, and 2018, respectively. During 2020, 2019 and 2018, the Company retired $3.1 million, $0.2 million, and $1.6 million, respectively, of fully depreciated property and equipment. Accrued liabilities consisted of the following (in thousands): December 31, 2020 2019 Accrued research and development services $ 28,380 $ 14,273 Accrued compensation and benefits 25,811 21,080 Accrued consulting and professional fees 18,969 13,691 Accrued sales allowances 14,115 11,326 Current portion of lease liabilities 5,087 3,434 Accrued royalties 2,451 1,971 Other 2,661 1,829 $ 97,474 $ 67,604

Stockholders' Equity

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Dec. 31, 2020
Equity [Abstract]
Stockholders' Equity	6. Stockholders’ Equity Stock Offerings In August 2020, the Company entered into an Agreement and Plan of Merger (the Merger Agreement) with CerSci Therapeutics Incorporated (CerSci), pursuant to which one of the Company’s wholly owned subsidiaries merged with and into CerSci, with CerSci as the surviving corporation and the Company’s wholly owned subsidiary. Approximately 1.2 million shares of the Company’s common stock with a value of $44.3 million were issued to CerSci’s former equity holders. The Company filed a registration statement on Form S-3 with the SEC to register the resale of the shares of the Company’s common stock issued in connection with its acquisition of CerSci. 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. 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 2010 Plan provided for the grant of options to employees, directors and consultants. The exercise price of options granted under the 2010 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 2010 Plan generally vested over a four-year The following table summarizes the Company’s stock option activity during the year ended December 31, 2020: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (years) Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2019 17,427,228 $ 28.69 Granted 1,937,006 $ 43.78 Exercised (2,571,633 ) $ 28.71 Cancelled/forfeited (350,607 ) $ 31.75 Outstanding at December 31, 2020 16,441,994 $ 30.40 6.8 $ 379,233 Vested at December 31, 2020 9,691,855 $ 29.71 6.0 $ 230,156 Unvested at December 31, 2020 6,750,139 $ 31.38 8.0 $ 149,078 Exercisable at December 31, 2020 9,691,855 $ 29.71 6.0 $ 230,156 The aggregate intrinsic value of options exercisable as of December 31, 2020 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 $53.46 per share. The aggregate intrinsic value of options exercised during the years ended December 31, 2020, 2019, and 2018 was approximately $55.5 million, $56.6 million, and $11.2 million, respectively, determined as of the date of exercise. The Company received $73.8 million in cash from options exercised during the year ended December 31, 2020. The weighted average per share fair value of options granted during the years ended December 31, 2020, 2019, and 2018 was approximately $24.16, $15.97, and $12.14, respectively. As of December 31, 2020, total unrecognized compensation cost related to stock options was approximately $99.1 million, and the weighted average period over which this cost is expected to be recognized is approximately 2.5 years. Restricted Stock The Company grants RSUs and PSUs, both of which are considered restricted stock, 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 restricted stock activity during the year ended December 31, 2020: Number of Shares Weighted Average Grant Date Fair Value Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2019 1,445,163 $ 24.50 Granted 1,079,727 $ 44.03 Vested (255,953 ) $ 23.83 Cancelled/forfeited (61,690 ) $ 35.95 Outstanding at December 31, 2020 2,207,247 $ 33.81 $ 117,999 700,156 and 448,632 PSUs were outstanding at December 31, 2020 and 2019, respectively. During the years ended 2020 and 2019, 255,878 and 481,036 PSUs were granted, respectively, none of which was vested. As of December 31, 2020, total unrecognized compensation cost related to RSUs and PSUs was approximately $41.7 million and 2.6 million, respectively, and the weighted average period over which the cost is expected to be recognized is approximately 2.7 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. In June 2016, June 2019 and June 2020, 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, 600,000 shares and 3,000,000 shares, respectively. At December 31, 2020, a total of 5,525,000 shares of common stock had been reserved for issuance under the Purchase Plan. At December 31, 2020, 3,106,995 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, 2020, 2019, and 2018, a total of 377,963, 269,037, and 233,720 shares of common stock were issued under the Purchase Plan at average per share prices of $18.94, $16.41, and $15.75, respectively. The weighted average per share fair value of purchase rights granted during the years ended December 31, 2020, 2019, and 2018 was $22.47, $14.24, and $8.25, respectively. During the years ended December 31, 2020, 2019, and 2018, the Company recorded cash received from the exercise of purchase rights of $7.2 million, $4.4 million, and $3.7 million, respectively.

401(k) Plan

401(k) Plan	12 Months Ended
401(k) Plan	Dec. 31, 2020
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 $5.1 million, $4.3 million, and $3.6 million for the years ended December 31, 2020, 2019, and 2018, respectively.

Income Taxes

Income Taxes	12 Months Ended
Income Taxes	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	8. Income Taxes Domestic and foreign pre-tax loss is as follows (in thousands): Years Ended December 31, 2020 2019 2018 Domestic $ (238,885 ) $ (123,411 ) $ (78,112 ) Foreign (42,088 ) (110,972 ) (165,824 ) $ (280,973 ) $ (234,383 ) $ (243,936 ) At December 31, 2020, the Company had federal, state, and foreign net operating loss (NOL) carryforwards of approximately $539.2 million, $416.3 million, and $1,186.5 million, respectively. The Company recognized state income tax provisions of $0.4 million, $0.9 million and $1.3 million for the years ended December 31, 2020, 2019 and 2018, respectively. The Company recognized foreign income tax in the amount of $0.2 million for the year ended December 31, 2020. These tax liabilities were associated with minimum taxes and a patent box entry tax for Switzerland in the current year and the apportionment of income to certain state jurisdictions which the Company did not have corresponding NOLs in 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, 2020, the Company had federal and state charitable contribution carryforwards of $120.8 million, which will begin to expire in 2021. At December 31, 2020, the Company had $55.5 million of federal R&D credit carryforwards of which $0.2 million will expire in 2021 unless utilized, and the remaining federal R&D credit carryforwards will begin to expire in 2022. At December 31, 2020, the Company had state R&D credit carryforwards of approximately $2.6 million that will begin to expire in 2024 and $16.5 million that have no expiration date. At December 31, 2020, the Company had foreign NOL carryforwards of approximately $1,186.5 million that will begin to expire in 2022 and $3.7 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, 2020 2019 Deferred tax assets NOL carryforwards 218,905 182,948 R&D credit carryforwards 63,886 48,069 Stock-based compensation 47,547 45,440 Charitable contributions 28,470 18,303 Lease liabilities 11,675 2,366 Intangibles 7,109 59,783 Capitalized R&D 6,073 7,607 Other 9,390 8,773 Total deferred tax assets 393,055 373,289 Valuation allowance (380,533 ) (370,783 ) Deferred tax liabilities Right-of-use assets (11,142 ) (2,301 ) Propery and equipment (1,380 ) (205 ) Total deferred tax liabilities (12,522 ) (2,506 ) 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 $9.8 million in 2020 primarily due to an increase in deferred tax assets generated from net operating losses, R&D credits and stock-based compensation expense, and the increase in tax attributes associated with the acquisition of CerSci, offset in part by the impact of the Switzerland tax reform, the remeasurement of deferred tax balance for changes in state tax rates, and limitations on executive stock compensation. On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (CARES Act) was enacted and signed into law in response to COVID-19. The CARES Act, among other things, included several significant provisions that impacted corporate taxpayers’ accounting for income taxes. Prior to the enactment of the CARES Act, the 2017 Tax Cuts and Jobs Act generally eliminated the ability to carryback NOLs, and permitted the NOLs arising in tax years beginning after December 31, 2017 to be carried forward indefinitely, limited to 80% of the taxpayer’s income. The CARES Act amended the NOL rules, suspending the 80% limitation on the utilization of NOLs generated after December 31, 2017 and before January 1, 2021. Additionally, the CARES Act allows corporate NOLs arising in taxable years beginning after December 31, 2017 and before January 1, 2021, to be carried back to each of the five taxable years preceding the taxable year of the loss. Also, the CARES Act allows companies to defer making certain payroll tax payments until future years. The Company did not have any qualitative or quantitative impact to the financials as a result of the CARES Act in the current year. 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. The tax reform also allowed the Company to take as a deduction for Cantonal purposes only, a portion of the increase in value of the intellectual property transferred to Switzerland. This deduction was available as a result of establishing Lucerne as the Cantonal location for the Company. As a result, during 2019 a deferred tax asset of $57.0 million was established which was the estimated amount that would be allowed as a future deduction. During December 2020, the Company moved to Basel-City from Lucerne. As a result, the intellectual property deduction is no longer available and has been reversed. Additionally, the deferred tax assets and net operating losses were remeasured at the amount and rate in which they are anticipated to reverse as a result of the change in jurisdiction. As a result of the Cantonal change, the deferred taxes for Switzerland decreased by $52.8 million. The adjustments made to the deferred tax assets are offset by a valuation allowance. 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, 2020 2019 2018 Amounts computed at statutory federal rate $ (59,004 ) $ (49,365 ) $ (51,226 ) Stock-based compensation and other permanent differences 991 5,691 3,379 Write-off of IP R&D 9,565 — — R&D credits (17,909 ) (16,687 ) (7,941 ) Change in valuation allowance 5,925 99,846 34,333 State taxes (5,038 ) (2,138 ) (1,017 ) Contingencies 2,665 1,861 2,938 Foreign rate differential 4,208 20,413 20,896 Limitation on executive compensation 3,705 1,178 53 Deferred rate adjustment 2,130 — — Switzerland tax reform 53,045 (59,181 ) — Other 328 (742 ) (159 ) Income tax expense $ 611 $ 876 $ 1,256 The tax years 2001-2019 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 $2.9 million, $1.9 million and $3.1 million for the years ended December 31, 2020, 2019 and 2018, respectively. 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, 2020 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, 2020 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, 2020 or 2019, respectively. Further, the Company did not recognize any interest and/or penalties in the statement of operations for the years ended December 31, 2020, 2019 and 2018, respectively, related to uncertain tax positions. The following table provides a reconciliation of changes in unrecognized tax benefits (in thousands): Years Ended December 31, 2020 2019 2018 Balance at beginning of period $ 6,945 $ 5,037 $ 1,933 Additions related to current period tax positions 2,722 1,908 3,104 Additions related to prior period tax positions 212 — — Reductions related to prior period tax positions (36 ) — — Balance at end of period $ 9,843 $ 6,945 $ 5,037

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2020
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 2% of net sales of NUPLAZID. License and Merger Agreements The Company has entered into various collaboration, licensing and merger agreements which provide the Company with rights to certain know-how, technology and patent rights. The agreements generally include upfront license fees, development and commercial milestone payments upon achievement of certain clinical and commercial development and annual net sales milestones, as well as royalties calculated as a percentage of product revenues, with rates that vary by agreement. The Company incurred $72.7 million, $1.4 million and $10.0 million in upfront and license payments in the years ended December 31, 2020, 2019 and 2018, respectively In May 2018, the Company signed an Exclusivity 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. In March 2020, the Company entered into a license agreement and research collaboration with Vanderbilt University and obtained exclusive worldwide rights to develop and commercialize novel drug candidates targeting positive allosteric modulators of the muscarinic M1 receptor (the M1 PAM program) with the potential to treat a range of central nervous system disorders. Under the terms of the agreement, the Company paid Vanderbilt University an upfront license fee of $10.0 million and may be required to pay up to $515.0 million in milestone payments based on the achievement of certain clinical and commercial development and annual net sales milestones. In addition, the Company may be required to pay Vanderbilt University tiered royalties based on net sales. Furthermore, the Company is required to spend a minimum annual amount in development and the pursuit of regulatory approval for the M1 PAM compounds over the first three years of the license agreement. Such amounts are not material to the Company. The license agreement was accounted for as an asset acquisition and the upfront cash payment of $10.0 million was expensed to research and development in the first quarter of 2020 as there is no future alternative use for the assets. In August 2020, the Company entered into the Merger Agreement with CerSci, with CerSci remaining as the surviving corporation and the Company’s wholly owned subsidiary. CerSci’s lead development program is a unique Reactive Species Decomposition Accelerant, a non-opioid, mechanism focused on interrupting pathways that sensitize neurons to pain. The portfolio contains additional preclinical stage programs, including brain penetrant compounds, with potential for symptomatic and disease modifying treatment utility in neurodegenerative diseases. The Company incurred an aggregate of $52.8 million in upfront consideration and transaction costs, of which, $44.3 million was paid through the issuance of approximately 1.2 million shares of the Company’s common stock. In addition, under the terms of the Merger Agreement, the Company may be required to pay CerSci’s former equity holders up to $887.0 million in cash upon the achievement of certain development, commercialization and sales milestones, in addition to tiered cash royalties in the mid-single digits based on annual net sales. As substantially all of the fair value of the gross assets acquired was concentrated in the in-process research and development intangible assets acquired, the Company concluded that this transaction did not meet the definition of a business combination pursuant to FASB Accounting Standard Codification Topic 805, Business Combinations. As such, the transaction was accounted for as an asset acquisition and the upfront consideration of $45.7 million was expensed to research and development in the third quarter of 2020 as there is no future alternative use for the assets. 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 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. On July 16, 2020, the parties filed a joint motion to continue to stay the derivative action until the defendants in the federal securities class action answer, or the federal securities class action is dismissed with prejudice and all appeals are exhausted, or any party to the stipulation to stay gives 15 days’ written notice that it no longer consents to the voluntary stay. The Court stayed the action on July 22, 2020. On September 9, 2020, the Court substituted plaintiffs and re-captioned the case Shumacher v. Davis et al., Case No. 20-cv-0238. On June 23, 2020, another derivative complaint (captioned Lazarus v. Davis et al., Case No. 20-cv-0843) was filed in the U.S. District Court for the District of Delaware. Like the previous derivative complaint, 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 September 9, 2020, the Court transferred the case to the U.S. District Court for the Southern District of California and re-captioned the case Lazarus v. Davis et al., Case No. 20-cv-1774. On July 24, 2020, the Company filed complaints against (i) Aurobindo Pharma Limited and its affiliate Aurobindo Pharma USA, Inc. and (ii) Teva Pharmaceuticals USA, Inc. and its affiliate Teva Pharmaceutical Industries Ltd. , and on July 30 , 2020, the Company filed complaints against (i) Hetero Labs Limited and its affiliates Hetero Labs Limited Unit-V and Hetero USA Inc. , (ii) MSN Laboratories Private Ltd. and its affiliate MSN Pharmaceuticals, Inc. , and (iii) Zydus Pharmaceuticals (USA) Inc. and its affiliate Cadila Healthcare Limited . These complaints, which were filed in the United States District Court for the District of Delaware, allege infringement of certain of the Company’s Orange Book-listed patents covering NUPLAZID. The cases have been assigned to the Honorable Richard G. Andrews. On September 1, 2020, Aurobindo filed its answer and counterclaims seeking declaratory judgments of noninfringement and invalidity. On September 22, 2020, the Company filed its answer to Aurobindo’s counterclaims. On August 31, 2020, Teva filed its answer and counterclaims seeking declaratory judgments of noninfringement and invalidity. On September 21, 2020, the Company filed its answer to Teva’s counterclaims. On October 5, 2020, Hetero filed its answer and counterclaims seeking declaratory judgments of noninfringement and invalidity. On October 26, 2020, the Company filed its answer to Hetero’s counterclaims. On September 30, 2020, MSN filed its answer and counterclaims seeking declaratory judgments of noninfringement and invalidity regarding certain of our Orange Book-listed patents covering NUPLAZID. On November 5, 2020, the Company filed its f irst a mended c omplaint against MSN in the United States District Court for the District of Delaware, alleging infringement of certain of our Orange Book-listed patents covering NUPLAZID. On November 19, 2020, MSN filed its answer and counterclaims seeking declaratory judgments of noninfringement and invalidity regarding certain of the Company’s Orange Book-listed patents covering NUPLAZID. On December 10, 2020, the Company filed its answer to MSN’s counterclaims. On November 2, 2020, Zydus filed its answer and counterclaims seeking declaratory judgments of noninfringement and invalidity. On November 23, 2020, the Company filed its answer to Zydus’s counterclaims. On December 8, 2020, the p arties’ j oint p roposed s cheduling o rder was entered by Judge Andrews. A joint trial in the matters is scheduled for May 15, 2023. Management currently believes that none of the foregoing claims or actions pending against the Company as of September 30, 2020 is likely to have, individually or in the aggregate, a material adverse effect on the Company’s business, liquidity, financial position, or results of operations. Given the unpredictability inherent in litigation, however, the Company cannot predict the outcome of these matters. The Company is unable to estimate possible losses or ranges of losses that may result from these matters, and therefore it has not accrued any amounts in connection with these matters 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 has cooperated with the DOJ’s request since that time. In October 2020, the DOJ advised the Company that it had concluded its investigation of the Company and would not be taking any further action related to the CID. As such, DOJ advised the Company that it does not need to respond further to the CID.

Leases

Leases	12 Months Ended
Leases	Dec. 31, 2020
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 leases facilities and certain equipment under noncancelable operating leases with remaining lease terms of 1.0 year to 10.4 years, some of which include options to extend the lease for up to two five-year The operating Years Ended December 31, 2020 2019 2018 Operating lease cost $ 6,917 $ 5,155 $ 4,503 Supplemental cash flow information related to the Company’s leases were as follows (in thousands): Years Ended December 31, 2020 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 4,480 $ 4,841 Right-of-use assets obtained in exchange for operating lease obligations: 42,039 13,399 The balance sheet classification of the Company’s lease liabilities was as follows (in thousands): December 31, 2020 December 31, 2019 Operating lease liabilities Current portion included in accrued liabilities $ 5,087 $ 3,434 Operating lease liabilities 44,460 6,361 Total operating lease liabilities $ 49,547 $ 9,795 Maturities of lease liabilities were as follows (in thousands): Operating Leases Years ending December 31, 2021 $ 5,284 2022 7,193 2023 6,635 2024 6,397 2025 5,922 Thereafter 29,762 Total lease payments 61,193 Less: Imputed interest (11,646 ) Total operating lease liabilities $ 49,547 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, 2020, the weighted average remaining lease term is 9.4 years and the weighted average discount rate used to determine the operating lease liability was 4.7%. In the fourth quarter of 2018, the Company entered into an agreement to lease the 4 th th $50.4 million over an initial term of 10 years and 9 months. In February 2020, the Company entered into the first amendment to the lease agreement to lease the 2 nd th th first quarter of 2021 and its amendment agreements , the Company established a letter of credit for $3.1 million, which has automatic annual extensions and is fully secured by restricted cash.

Selected Quarterly Financial Da

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
Selected Quarterly Financial Data (Unaudited)	Dec. 31, 2020
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, 2020 and 2019 are as follows (in thousands, except per share data): Fiscal Year 2020 Quarters 1st 2nd 3rd 4th Total Revenues $ 90,068 $ 110,103 $ 120,577 $ 121,007 $ 441,755 Gross profit (1) $ 87,269 $ 107,204 $ 118,572 $ 118,499 $ 431,544 Net loss $ (88,023 ) $ (42,141 ) $ (84,660 ) $ (66,760 ) $ (281,584 ) Basic and diluted net loss per share (2) $ (0.57 ) $ (0.27 ) $ (0.05 ) $ (0.42 ) $ (1.79 ) 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 ) ( 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.

SCHEDULE II - Valuation and Qua

SCHEDULE II - Valuation and Qualifying Accounts	12 Months Ended
SCHEDULE II - Valuation and Qualifying Accounts	Dec. 31, 2020
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, 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 For the year ended December 31, 2020 $ 2,576 $ 51,684 $ (47,463 ) $ (2,576 ) $ 4,221

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2020
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, 2020 Twelve Months Ended December 31, 2019 Beginning of period End of period Beginning of period End of period Cash and cash equivalents $ 189,680 $ 326,028 $ 134,758 $ 189,680 Restricted cash 4,787 5,770 4,826 4,787 Total cash, cash equivalents and restricted cash shown in the statements of cash flows $ 194,467 $ 331,798 $ 139,584 $ 194,467
Investment Securities	Investment Securities Currently, all of the Company’s investment securities are debt 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 credit losses. Allowances for distribution fees, prompt payment discounts and chargebacks are based on contractual terms. The Company adopted Financial Accounting Standards Board (FASB) Accounting Standards Codification 326-20, Financial Instruments – Credit Losses Although the Company has not historically experienced significant credit losses, the Company’s exposure may increase due to uncertainties associated with the global economic recession and other disruptions resulting from the COVID-19 pandemic.
Inventory	Inventory Inventory is stated at the lower of cost or net realizable value under the first-in, first-out method (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, 2020, 2019 and 2018, the Company recorded charges of $0.4 million, $1.1 million and $2.7 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, 2020, 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, 2020, 2019 and 2018. As of December 31, 2020, estimated future amortization expense related to the Company’s intangible asset was $1.1 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.
Acquisitions	Acquisitions The Company accounts for
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 $51.1 million, $38.3 million and $39.8 million in advertising costs during the years ended December 31, 2020, 2019 and 2018, respectively, related to NUPLAZID. No advertising costs were capitalized as prepaid expenses at December 31, 2020 or 2019.
Revenue Recognition	Revenue Recognition Product Sales, Net The Company accounts for contracts with its customers in accordance with Revenue from Contracts with Customers (Topic 606), 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 still estimated to be incurred . 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 upfront consideration and transaction costs associated with acquired in-process research and development are also included in the research and development 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, it records those amounts as prepaid expenses on its 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, 2020, the Company’s four largest customers represented approximately 74% of the Company’s product revenue and 75% of the Company’s accounts receivable balance at December 31, 2020. 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.
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, 2020 2019 2018 Stock Options: Expected volatility 63 % 62 % 71 % Risk-free interest rate 1 % 2 % 3 % Expected dividend yield 0 % 0 % 0 % Expected life of options in years 5.5 5.7 5.7 Years Ended December 31, 2020 2019 2018 Employee Stock Purchase Plan: Expected volatility 50%-76% 62%-86% 59%-79% Risk-free interest rate 0.1%-0.2% 1.5%-2.4% 2.1%-2.8% 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 over a four-year period. The fair value of RSUs expected to vest are recognized and amortized on a straight-line basis over the requisite service period, which is generally the vesting period. The fair value of performance-based stock units (PSUs) is estimated based on the closing market price of the Company’s common stock on the date of grant. PSUs vest upon the achievement of certain pre-defined company-specific performance-based criteria. Expense related to these PSUs is generally recognized ratably over the expected performance period once the pre-defined performance-based criteria for vesting becomes probable. 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, 2020 2019 2018 Cost of product sales $ 2,632 $ 2,936 $ 3,863 Research and development 31,314 32,533 32,038 Sales, general and administrative 50,476 46,796 45,663 $ 84,422 $ 82,265 $ 81,564
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 to be 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, 2020, 2019 and 2018, options, employee stock purchase rights, RSUs, PSUs, and warrants covering a total of approximately 19,331,000 shares, 19,516,000 shares and 20,824,000 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, 2020, 2019 and 2018 were generated from customers in the United States.
Recently Issued Accounting Standards	Recently Issued Accounting Standards In June 2016, the FASB issued ASU 2016-13, Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments 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 December 2019, the FASB issued ASU 2019-12 Income Taxes (Topic 740), Simplifying the Accounting for Income Taxes

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
Summary of Significant Accounting Policies (Tables)	Dec. 31, 2020
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, 2020 Twelve Months Ended December 31, 2019 Beginning of period End of period Beginning of period End of period Cash and cash equivalents $ 189,680 $ 326,028 $ 134,758 $ 189,680 Restricted cash 4,787 5,770 4,826 4,787 Total cash, cash equivalents and restricted cash shown in the statements of cash flows $ 194,467 $ 331,798 $ 139,584 $ 194,467
Schedule of Estimated Useful Lives by Major Asset Category	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
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, 2020 2019 2018 Stock Options: Expected volatility 63 % 62 % 71 % Risk-free interest rate 1 % 2 % 3 % Expected dividend yield 0 % 0 % 0 % Expected life of options in years 5.5 5.7 5.7
Weighted-Average Assumptions Used to Estimate Fair Value of Employee Stock Purchase Plan Rights	Years Ended December 31, 2020 2019 2018 Employee Stock Purchase Plan: Expected volatility 50%-76% 62%-86% 59%-79% Risk-free interest rate 0.1%-0.2% 1.5%-2.4% 2.1%-2.8% 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, 2020 2019 2018 Cost of product sales $ 2,632 $ 2,936 $ 3,863 Research and development 31,314 32,533 32,038 Sales, general and administrative 50,476 46,796 45,663 $ 84,422 $ 82,265 $ 81,564

Investments (Tables)

Investments (Tables)	12 Months Ended
Investments (Tables)	Dec. 31, 2020
Investments Debt And Equity Securities [Abstract]
Carrying Value and Amortized Cost of Company 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, 2020 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value U.S. Treasury notes $ 205,111 $ 6 $ (27 ) $ 205,090 Government sponsored enterprise securities 10,004 — (5 ) 9,999 Corporate debt securities 52,341 47 — * 52,388 Commercial paper 38,443 21 (11 ) 38,453 $ 305,899 $ 74 $ (43 ) $ 305,930 _______________________ * Unrealized loss was less than $500. 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
Summary of Gross Unrealized Losses and Fair Value of Available-For-Sale Investment Securities 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, 2020 and December 31, 2019, 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, 2020: U.S. Treasury notes $ 129,631 $ (27 ) $ — $ — $ 129,631 $ (27 ) Government sponsored enterprise securities 10,004 (5 ) — — 10,004 (5 ) Corporate debt securities 6,252 — * — — 6,252 — * Commercial paper 23,466 (11 ) 23,466 (11 ) Total $ 169,353 $ (43 ) $ — $ — $ 169,353 $ (43 ) 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 ) _______________________ * Unrealized loss was less than $500.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
Fair Value Measurements (Tables)	Dec. 31, 2020
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, 2020 and 2019 consisted of the following (in thousands): Fair Value Measurements at Reporting Date Using December 31, 2020 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Money market fund $ 300,339 $ 300,339 $ — $ — U.S. Treasury notes 230,088 230,088 — — Government sponsored enterprise securities 9,999 — 9,999 — Equity securities 1,309 1,309 — — Corporate debt securities 52,388 — 52,388 — Commercial paper 38,453 — 38,453 — $ 632,576 $ 531,736 $ 100,840 $ — 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 $ —

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	12 Months Ended
Balance Sheet Details (Tables)	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Schedule of Inventory	Inventory consisted of the following (in thousands): December 31, 2020 2019 Finished goods $ 1,453 $ 3,175 Work in process 6,367 1,685 Raw material 1,862 1,481 $ 9,682 $ 6,341
Property and Equipment, Net	Property and equipment, net, consisted of the following (in thousands): December 31, 2020 2019 Computers and software $ 5,315 $ 3,724 Leasehold improvements $ 4,033 $ 2,560 Furniture and fixtures $ 3,648 $ 2,115 Machinery and equipment $ 113 $ 113 $ 13,109 $ 8,512 Accumulated depreciation $ (3,948 ) $ (5,332 ) $ 9,161 $ 3,180
Schedule of Accrued Liabilities	Accrued liabilities consisted of the following (in thousands): December 31, 2020 2019 Accrued research and development services $ 28,380 $ 14,273 Accrued compensation and benefits 25,811 21,080 Accrued consulting and professional fees 18,969 13,691 Accrued sales allowances 14,115 11,326 Current portion of lease liabilities 5,087 3,434 Accrued royalties 2,451 1,971 Other 2,661 1,829 $ 97,474 $ 67,604

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
Stockholders' Equity (Tables)	Dec. 31, 2020
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, 2020: Number of Shares Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (years) Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2019 17,427,228 $ 28.69 Granted 1,937,006 $ 43.78 Exercised (2,571,633 ) $ 28.71 Cancelled/forfeited (350,607 ) $ 31.75 Outstanding at December 31, 2020 16,441,994 $ 30.40 6.8 $ 379,233 Vested at December 31, 2020 9,691,855 $ 29.71 6.0 $ 230,156 Unvested at December 31, 2020 6,750,139 $ 31.38 8.0 $ 149,078 Exercisable at December 31, 2020 9,691,855 $ 29.71 6.0 $ 230,156
Summary of Company's RSU Activity	The following table summarizes the Company’s restricted stock activity during the year ended December 31, 2020: Number of Shares Weighted Average Grant Date Fair Value Aggregate Intrinsic Value (in thousands) Outstanding at December 31, 2019 1,445,163 $ 24.50 Granted 1,079,727 $ 44.03 Vested (255,953 ) $ 23.83 Cancelled/forfeited (61,690 ) $ 35.95 Outstanding at December 31, 2020 2,207,247 $ 33.81 $ 117,999

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Dec. 31, 2020
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, 2020 2019 2018 Domestic $ (238,885 ) $ (123,411 ) $ (78,112 ) Foreign (42,088 ) (110,972 ) (165,824 ) $ (280,973 ) $ (234,383 ) $ (243,936 )
Components of Deferred Tax Assets	The components of the deferred tax assets are as follows (in thousands): December 31, 2020 2019 Deferred tax assets NOL carryforwards 218,905 182,948 R&D credit carryforwards 63,886 48,069 Stock-based compensation 47,547 45,440 Charitable contributions 28,470 18,303 Lease liabilities 11,675 2,366 Intangibles 7,109 59,783 Capitalized R&D 6,073 7,607 Other 9,390 8,773 Total deferred tax assets 393,055 373,289 Valuation allowance (380,533 ) (370,783 ) Deferred tax liabilities Right-of-use assets (11,142 ) (2,301 ) Propery and equipment (1,380 ) (205 ) Total deferred tax liabilities (12,522 ) (2,506 ) 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, 2020 2019 2018 Amounts computed at statutory federal rate $ (59,004 ) $ (49,365 ) $ (51,226 ) Stock-based compensation and other permanent differences 991 5,691 3,379 Write-off of IP R&D 9,565 — — R&D credits (17,909 ) (16,687 ) (7,941 ) Change in valuation allowance 5,925 99,846 34,333 State taxes (5,038 ) (2,138 ) (1,017 ) Contingencies 2,665 1,861 2,938 Foreign rate differential 4,208 20,413 20,896 Limitation on executive compensation 3,705 1,178 53 Deferred rate adjustment 2,130 — — Switzerland tax reform 53,045 (59,181 ) — Other 328 (742 ) (159 ) Income tax expense $ 611 $ 876 $ 1,256
Unrecognized Tax Benefits	The following table provides a reconciliation of changes in unrecognized tax benefits (in thousands): Years Ended December 31, 2020 2019 2018 Balance at beginning of period $ 6,945 $ 5,037 $ 1,933 Additions related to current period tax positions 2,722 1,908 3,104 Additions related to prior period tax positions 212 — — Reductions related to prior period tax positions (36 ) — — Balance at end of period $ 9,843 $ 6,945 $ 5,037

Leases (Tables)

Leases (Tables)	12 Months Ended
Leases (Tables)	Dec. 31, 2020
Leases [Abstract]
Summary of Operating Lease Costs	The operating Years Ended December 31, 2020 2019 2018 Operating lease cost $ 6,917 $ 5,155 $ 4,503
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): Years Ended December 31, 2020 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 4,480 $ 4,841 Right-of-use assets obtained in exchange for operating lease obligations: 42,039 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, 2020 December 31, 2019 Operating lease liabilities Current portion included in accrued liabilities $ 5,087 $ 3,434 Operating lease liabilities 44,460 6,361 Total operating lease liabilities $ 49,547 $ 9,795
Summary of Maturities of Lease Liabilities	Maturities of lease liabilities were as follows (in thousands): Operating Leases Years ending December 31, 2021 $ 5,284 2022 7,193 2023 6,635 2024 6,397 2025 5,922 Thereafter 29,762 Total lease payments 61,193 Less: Imputed interest (11,646 ) Total operating lease liabilities $ 49,547

Selected Quarterly Financial _2

Selected Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
Selected Quarterly Financial Data (Unaudited) (Tables)	Dec. 31, 2020
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data	Fiscal Year 2020 Quarters 1st 2nd 3rd 4th Total Revenues $ 90,068 $ 110,103 $ 120,577 $ 121,007 $ 441,755 Gross profit (1) $ 87,269 $ 107,204 $ 118,572 $ 118,499 $ 431,544 Net loss $ (88,023 ) $ (42,141 ) $ (84,660 ) $ (66,760 ) $ (281,584 ) Basic and diluted net loss per share (2) $ (0.57 ) $ (0.27 ) $ (0.05 ) $ (0.42 ) $ (1.79 ) 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 ) ( 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, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations [Abstract]
Cash and cash equivalents	$ 326,028	$ 189,680	$ 134,758
Restricted cash	5,770	4,787	4,826
Total cash, cash equivalents and restricted cash shown in the statements of cash flows	$ 331,798	$ 194,467	$ 139,584	$ 71,893

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Additional Information (Detail)	1 Months Ended	12 Months Ended
	Apr. 30, 2016USD ($)	Dec. 31, 2020USD ($)CustomerSegmentshares	Dec. 31, 2019USD ($)Customershares	Dec. 31, 2018USD ($)Customershares
Summary Of Significant Accounting Policy [Line Items]
Charge on finished goods inventory		$ 400,000	$ 1,100,000	$ 2,700,000
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	1,477,000	1,476,000
Estimated future amortization expense, 2021		1,100,000
Advertising costs		51,100,000	38,300,000	$ 39,800,000
Advertising costs capitalized as prepaid expenses		$ 0	$ 0
Number of large customers \| Customer		4	4	4
Antidilutive securities to purchase common stock \| shares		19,331,000	19,516,000	20,824,000
Number of business segments \| Segment		1
Customer Concentration Risk \| Revenue, Product and Service Benchmark \| Four Customers
Summary Of Significant Accounting Policy [Line Items]
Concentration risk, percentage		74.00%	77.00%	85.00%
Customer Concentration Risk \| Accounts Receivable \| Four Customers
Summary Of Significant Accounting Policy [Line Items]
Concentration risk, percentage		75.00%	75.00%	84.00%

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, 2020
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, 2020	Dec. 31, 2019	Dec. 31, 2018
Assumptions Used To Determine Fair Value Options [Line Items]
Expected volatility	63.00%	62.00%	71.00%
Risk-free interest rate	1.00%	2.00%	3.00%
Expected dividend yield	0.00%	0.00%	0.00%
Expected life of options in years	5 years 6 months	5 years 8 months 12 days	5 years 8 months 12 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, 2020	Dec. 31, 2019	Dec. 31, 2018
Employee Stock Purchase Plan [Line Items]
Expected volatility, minimum	50.00%	62.00%	59.00%
Expected volatility, maximum	76.00%	86.00%	79.00%
Risk-free interest rate, minimum	0.10%	1.50%	2.10%
Risk-free interest rate, maximum	0.20%	2.40%	2.80%
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, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 84,422	$ 82,265	$ 81,564
Cost of product sales
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	2,632	2,936	3,863
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	31,314	32,533	32,038
Sales, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 50,476	$ 46,796	$ 45,663

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, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Estimated Fair Value	$ 305,930	$ 507,749
Equity securities, Amortized Cost	305,899
Equity securities, Unrealized Gains	74
Equity securities, Unrealized Losses	(43)
Equity securities, Estimated Fair Value	305,930
Debt and equity securities, Amortized Cost	305,899	507,465
Debt and equity securities, Unrealized Gains	74	335
Debt and equity securities, Unrealized Losses	(43)	(51)
Debt and equity securities, Estimated Fair Value	305,930	507,749
US Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	205,111	228,609
Debt securities, Unrealized Gains	6	7
Debt securities, Unrealized Losses	(27)	(13)
Debt securities, Estimated Fair Value	205,090	228,603
Equity securities, Amortized Cost			$ 228,609
Equity securities, Unrealized Gains			7
Equity securities, Unrealized Losses			(13)
Equity securities, Estimated Fair Value			228,603
US Government Sponsored Enterprises Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	10,004	88,920
Debt securities, Unrealized Gains		5
Debt securities, Unrealized Losses	(5)	(30)
Debt securities, Estimated Fair Value	9,999	88,895
Equity securities, Amortized Cost			88,920
Equity securities, Unrealized Gains			5
Equity securities, Unrealized Losses			(30)
Equity securities, Estimated Fair Value			88,895
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	52,341	87,785
Debt securities, Unrealized Gains	47	262
Debt securities, Unrealized Losses		(8)
Debt securities, Estimated Fair Value	52,388	88,039
Equity securities, Amortized Cost			87,785
Equity securities, Unrealized Gains			262
Equity securities, Unrealized Losses			(8)
Equity securities, Estimated Fair Value			88,039
Commercial paper
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	38,443	102,151
Debt securities, Unrealized Gains	21	61
Debt securities, Unrealized Losses	(11)
Debt securities, Estimated Fair Value	$ 38,453	$ 102,212
Equity securities, Amortized Cost			102,151
Equity securities, Unrealized Gains			61
Equity securities, Estimated Fair Value			$ 102,212

Investments - Carrying Value _2

Investments - Carrying Value and Amortized Cost of Company's Investments Summarized by Major Security Type (Parenthetical) (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Corporate debt securities \| Maximum
Schedule of Available-for-sale Securities [Line Items]
Unrealized loss on securities	$ 500

Investments - Additional Inform

Investments - Additional Information (Detail) $ in Millions	12 Months Ended
Investments - Additional Information (Detail) $ in Millions	Dec. 31, 2020Security	Dec. 31, 2019USD ($)Security
Investments Debt And Equity Securities [Abstract]
Available-for-sale, investment securities held with maturity dates of more than one year and less than two years \| $		$ 24.3
Available-for-sale investment securities contractual maturity dates	less than one year
Number of available-for-sale investment securities in unrealized loss position \| Security	24	20

Investments - Summary of Gross

Investments - Summary of Gross Unrealized Losses and Fair Value of Available-For-Sale Investment Securities in Unrealized Loss Position (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	$ 169,353	$ 220,834
Less Than 12 Months, Unrealized Losses	(43)	(51)
Total, Estimated Fair Value	169,353	220,834
Total, Unrealized Losses	(43)	(51)
US Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	129,631	148,397
Less Than 12 Months, Unrealized Losses	(27)	(13)
Total, Estimated Fair Value	129,631	148,397
Total, Unrealized Losses	(27)	(13)
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	6,252	11,334
Less Than 12 Months, Unrealized Losses		(8)
Total, Estimated Fair Value	6,252	11,334
Total, Unrealized Losses		(8)
US Government Sponsored Enterprises Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	10,004	61,103
Less Than 12 Months, Unrealized Losses	(5)	(30)
Total, Estimated Fair Value	10,004	61,103
Total, Unrealized Losses	(5)	$ (30)
Commercial paper
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	23,466
Less Than 12 Months, Unrealized Losses	(11)
Total, Estimated Fair Value	23,466
Total, Unrealized Losses	$ (11)

Investments - Summary of Gros_2

Investments - Summary of Gross Unrealized Losses and Fair Value of Available-For-Sale Investment Securities in Unrealized Loss Position (Parenthetical) (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Corporate debt securities \| Maximum
Schedule of Available-for-sale Securities [Line Items]
Unrealized loss on securities	$ 500

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, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	$ 632,576	$ 623,123
Money market fund
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	300,339	98,084
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	531,736	328,994
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	300,339	98,084
Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	100,840	294,129
U.S. Treasury notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	230,088	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	230,088	228,603
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	1,309	2,307
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	1,309	2,307
US Government Sponsored Enterprises Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	9,999	103,878
US Government Sponsored Enterprises Debt Securities [Member] \| Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	9,999	103,878
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	52,388	88,039
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	52,388	88,039
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	38,453	102,212
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	$ 38,453	$ 102,212

Balance Sheet Details - Schedul

Balance Sheet Details - Schedule of Inventory (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Finished goods	$ 1,453	$ 3,175
Work in process	6,367	1,685
Raw material	1,862	1,481
Inventory	$ 9,682	$ 6,341

Balance Sheet Details - Propert

Balance Sheet Details - Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 13,109	$ 8,512
Accumulated depreciation	(3,948)	(5,332)
Property and equipment, net	9,161	3,180
Machinery and Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	113	113
Computers and Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,315	3,724
Leasehold Improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,033	2,560
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 3,648	$ 2,115

Balance Sheet Details - Additio

Balance Sheet Details - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Depreciation of property and equipment	$ 1,455	$ 1,289	$ 1,529
Removal of fully depreciated property, machinery and equipment	$ 3,100	$ 200	$ 1,600

Balance Sheet Details - Sched_2

Balance Sheet Details - Schedule of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Payables And Accruals [Abstract]
Accrued research and development services	$ 28,380	$ 14,273
Accrued compensation and benefits	25,811	21,080
Accrued consulting and professional fees	18,969	13,691
Accrued sales allowances	14,115	11,326
Current portion of lease liabilities	5,087	3,434
Accrued royalties	2,451	1,971
Other	2,661	1,829
Accrued liabilities	$ 97,474	$ 67,604

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended								12 Months Ended
	Aug. 31, 2020	Jun. 30, 2020	Sep. 30, 2019	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2010
Class of Stock [Line Items]
Issuance of common stock in connection with asset acquisition									$ 44,280
Net proceeds from sale of common stock			$ 271,500						$ 80,996	$ 371,847	$ 306,647
Issuance of common stock in public offering, net of issuance costs (in shares)			7,187,500
Options vesting period									4 years
Closing market price of Common stock									$ 53.46
Aggregate intrinsic value of stock options exercised									$ 55,500	$ 56,600	$ 11,200
Cash received from options exercised									$ 73,800
Weighted average per share fair value of options granted									$ 24.16	$ 15.97	$ 12.14
Unrecognized compensation costs									$ 99,100
Weighted average period cost expected to be recognized									2 years 6 months
Terms of award									PSUs for which the number of shares issuable at the end of performance period can reach up to 200% of the shares approved in the award based on the achievement of certain pre-defined Acadia-specific performance criteria and continued employment through the vesting period
Issuance of common stock pursuant to employee stock purchase plan									$ 7,162	$ 4,411	$ 3,682
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									28,426,504
Common stock available for grants									9,777,263
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 periods additional number of shares could be added to shares authorized for issuance									10 years
PSU
Class of Stock [Line Items]
Unrecognized compensation costs									$ 2,600
Weighted average period cost expected to be recognized									1 year 6 months
Granted									255,878	481,036
Aggregate Intrinsic Value, Outstanding									$ 37,400
Outstanding shares									700,156	448,632
Restricted Stock Units
Class of Stock [Line Items]
Unrecognized compensation costs									$ 41,700
Weighted average period cost expected to be recognized									2 years 8 months 12 days
Employee Stock Purchase Plan
Class of Stock [Line Items]
Number of common stock authorized for issuance									5,525,000
Common stock reserved for issuance under stock purchase plan		3,000,000		600,000			400,000
Common stock remained available for issuance pursuant to the Purchase Plan									3,106,995
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									377,963	269,037	233,720
Average per share price of stock issued under purchase plan									$ 18.94	$ 16.41	$ 15.75
Weighted average per share fair value of purchase rights granted									$ 22.47	$ 14.24	$ 8.25
Issuance of common stock pursuant to employee stock purchase plan									$ 7,200	$ 4,400	$ 3,700
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
Cersci Therapeutics
Class of Stock [Line Items]
Issuance of common stock in connection with asset acquisition, Shares	1,200,000
Issuance of common stock in connection with asset acquisition	$ 44,300

Summary of Company's Stock Opti

Summary of Company's Stock Option Activity (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)$ / sharesshares
Number of Shares
Options Outstanding, Beginning Balance \| shares	17,427,228
Granted \| shares	1,937,006
Exercised \| shares	(2,571,633)
Cancelled/forfeited \| shares	(350,607)
Options Outstanding, Ending Balance \| shares	16,441,994
Vested at December 31, 2020 \| shares	9,691,855
Unvested at December 31, 2020 \| shares	6,750,139
Exercisable \| shares	9,691,855
Weighted Average Exercise Prices
Weighted Average Exercise Prices, Beginning Balance \| $ / shares	$ 28.69
Weighted Average Exercise Prices, granted \| $ / shares	43.78
Weighted Average Exercise Prices, exercised \| $ / shares	28.71
Weighted Average Exercise Prices, Cancelled/forfeited \| $ / shares	31.75
Weighted Average Exercise Prices, Ending Balance \| $ / shares	30.40
Weighted Average Exercise Prices, Vested \| $ / shares	29.71
Weighted Average Exercise Prices, Unvested \| $ / shares	31.38
Weighted Average Exercise Prices, Exercisable \| $ / shares	$ 29.71
Weighted average remaining contractual term, Outstanding	6 years 9 months 18 days
Weighted average remaining contractual term, Vested	6 years
Weighted average remaining contractual term, Unvested	8 years
Weighted average remaining contractual term, Exercisable	6 years
Aggregate Intrinsic Value, Outstanding \| $	$ 379,233
Aggregate Intrinsic Value, Vested \| $	230,156
Aggregate Intrinsic Value, Unvested \| $	149,078
Aggregate Intrinsic Value, Exercisable \| $	$ 230,156

Summary of Company's RSU Activi

Summary of Company's RSU Activity (Detail) - Restricted Stock Units and Performance Stock Units $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)$ / sharesshares
Number of Shares
Outstanding, Begining Balance \| shares	1,445,163
Granted \| shares	1,079,727
Vested \| shares	(255,953)
Cancelled/forfeited \| shares	(61,690)
Outstanding, Ending Balance \| shares	2,207,247
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value , Begining Balance \| $ / shares	$ 24.50
Weighted Average Grant Date Fair Value, Granted \| $ / shares	44.03
Weighted Average Grant Date Fair Value, Vested \| $ / shares	23.83
Weighted Average Grant Date Fair Value, Cancelled/forfeited \| $ / shares	35.95
Weighted Average Grant Date Fair Value, Ending Balance \| $ / shares	$ 33.81
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Outstanding \| $	$ 117,999

401 (k) Plan - Additional Infor

401 (k) Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
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	$ 5.1	$ 4.3	$ 3.6

Income Taxes - Summary of Domes

Income Taxes - Summary of Domestic and Foreign Pre-tax Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest [Abstract]
Domestic pre-tax income (loss)	$ (238,885)	$ (123,411)	$ (78,112)
Foreign pre-tax income (loss)	(42,088)	(110,972)	(165,824)
Total pre-tax income (loss)	$ (280,973)	$ (234,383)	$ (243,936)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
Income Taxes - Additional Information (Detail) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax [Line Items]
State income tax provision	$ 400,000	$ 900,000	$ 1,300,000
Foreign Income Tax Expense (Benefit)	200,000
Charitable contribution carryforwards	28,470,000	18,303,000
Federal R&D credit carryforwards	55,500,000
Increase in valuation allowance of deferred tax assets	9,800,000
Limitation on the utilization of NOLs, percentage				80.00%
Deferred tax asset , Switzerland tax reform	52,800,000	57,000,000
Unrecognized tax reserves recorded during period	2,900,000	1,900,000	3,100,000
Interest and/or penalties accrued	0	0
Interest and/or penalties	0	$ 0	$ 0
Federal
Income Tax [Line Items]
Operating loss carryforwards	539,200,000
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	120,800
State
Income Tax [Line Items]
Operating loss carryforwards	$ 416,300,000
Remaining net operating loss carryforward, expiration year	2026
Research and development credit carryforwards with no expiration date	$ 16,500,000
State \| Expiring in 2024
Income Tax [Line Items]
Net operating loss carryforwards with no expiration date	2,600,000
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	120,800
Foreign
Income Tax [Line Items]
Operating loss carryforwards	$ 1,186,500,000
Remaining net operating loss carryforward, expiration year	2026
Net operating loss carryforwards with no expiration date	$ 3,700,000
Foreign \| Operating Loss Carryforwards Expiring 2022
Income Tax [Line Items]
Operating loss carryforwards	1,186,500,000
Expire in 2021
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, 2020	Dec. 31, 2019
Deferred tax assets
NOL carryforwards	$ 218,905	$ 182,948
R&D credit carryforwards	63,886	48,069
Stock-based compensation	47,547	45,440
Charitable contributions	28,470	18,303
Lease liabilities	11,675	2,366
Intangibles	7,109	59,783
Capitalized R&D	6,073	7,607
Other	9,390	8,773
Total deferred tax assets	393,055	373,289
Valuation allowance	(380,533)	(370,783)
Deferred tax liabilities
Right-of-use assets	(11,142)	(2,301)
Propery and equipment	(1,380)	(205)
Total deferred tax liabilities	$ (12,522)	$ (2,506)

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, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Amounts computed at statutory federal rate	$ (59,004)	$ (49,365)	$ (51,226)
Stock-based compensation and other permanent differences	991	5,691	3,379
Write-off of IP R&D	9,565
R&D credits	(17,909)	(16,687)	(7,941)
Change in valuation allowance	5,925	99,846	34,333
State taxes	(5,038)	(2,138)	(1,017)
Contingencies	2,665	1,861	2,938
Foreign rate differential	4,208	20,413	20,896
Limitation on executive compensation	3,705	1,178	53
Deferred rate adjustment	2,130
Switzerland tax reform	53,045	(59,181)
Other	328	(742)	(159)
Income tax expense	$ 611	$ 876	$ 1,256

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Balance at beginning of period	$ 6,945	$ 5,037	$ 1,933
Additions related to current period tax positions	2,722	1,908	3,104
Additions related to prior period tax positions	212
Reductions related to prior period tax positions	(36)
Balance at end of period	$ 9,843	$ 6,945	$ 5,037

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended				3 Months Ended		12 Months Ended
	Aug. 31, 2020	Mar. 31, 2020	Aug. 31, 2018	May 31, 2018	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2016
Other Commitments [Line Items]
Gain (loss) on strategic investment							$ (997)	$ 997	$ (1,840)
Restricted cash							5,770	4,787	4,826
Corporate Credit Card Program \| Letter of Credit
Other Commitments [Line Items]
Restricted cash										$ 2,000
Fleet Program \| Letter of Credit
Other Commitments [Line Items]
Restricted cash							400
Other assets
Other Commitments [Line Items]
Aggregate carrying amount of strategic equity investment							1,300	2,300
Other expense
Other Commitments [Line Items]
Gain (loss) on strategic investment							(1,000)	1,000
Cersci Therapeutics
Other Commitments [Line Items]
Upfront consideration and transaction costs	$ 52,800
Upfront payment	$ 44,300
Upfront payment conditions	The Company incurred an aggregate of $52.8 million in upfront consideration and transaction costs, of which, $44.3 million was paid through the issuance of approximately 1.2 million shares of the Company’s common stock.
Common stock issuance	1,200,000
Cersci Therapeutics \| Research and development
Other Commitments [Line Items]
Assets acquisition and upfront payment					$ 45,700
License Agreements
Other Commitments [Line Items]
Upfront payment							$ 72,700	$ 1,400	10,000
License Agreements \| Neuren \| North America
Other Commitments [Line Items]
Upfront payment		$ 10,000
Upfront license fee			$ 10,000
License Agreements \| Neuren \| Research and development \| North America
Other Commitments [Line Items]
Upfront payment						$ 10,000			$ 10,000
Exclusivity Deed \| Neuren
Other Commitments [Line Items]
Aggregate carrying amount of strategic equity investment				$ 3,100
Shares subscribed				1,330,000
Exclusivity Deed \| Neuren \| Sales, general and administrative
Other Commitments [Line Items]
Payments for exclusive right				$ 900
Maximum
Other Commitments [Line Items]
Percentage of royalty payments obligation on net product sales							2.00%
Mile stone payments payable							$ 2,200,000
Maximum \| Cersci Therapeutics \| Development Commercialization and Sales Milestones
Other Commitments [Line Items]
Compensation expense related to mergers to former holders	$ 887,000
Maximum \| License Agreements \| Neuren \| North America
Other Commitments [Line Items]
Mile stone payments payable		$ 515,000	$ 455,000			$ 515,000

Leases - Additional Information

Leases - Additional Information (Detail) $ in Thousands	3 Months Ended	12 Months Ended
Leases - Additional Information (Detail) $ in Thousands	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)Term	Sep. 30, 2020USD ($)	Feb. 29, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2015
Lessee Lease Description [Line Items]
Operating lease, expiration year		2031-02
Operating lease, description		The Company leases facilities and certain equipment under noncancelable operating leases with remaining lease terms of 1.0 year to 10.4 years, some of which include options to extend the lease for up to two five-year terms.
Operating lease, option to extend		true
Operating lease, options to extend		some of which include options to extend the lease for up to two five-year terms.
Weighted average remaining lease term		9 years 4 months 24 days
Weighted average discount rate		4.70%
Capitalization of right of use asset			$ 40,300
Capitalization of lease liability			$ 40,300
Restricted cash		$ 5,770			$ 4,787	$ 4,826
Corporate Office Space Lease Agreement
Lessee Lease Description [Line Items]
Operating leases arrangement term				10 years 7 months		10 years 9 months
Corporate Office Space Lease Agreement \| Letter of Credit
Lessee Lease Description [Line Items]
Restricted cash		$ 3,100
California \| Corporate Office Space Lease Agreement
Lessee Lease Description [Line Items]
Minimum lease payment amount	$ 51,400			$ 25,300		$ 50,400
Lease commencement period	first quarter of 2021
Minimum
Lessee Lease Description [Line Items]
Operating lease remaining lease term		1 year
Maximum
Lessee Lease Description [Line Items]
Operating lease remaining lease term		10 years 4 months 24 days
Operating lease, renewal term		5 years
Number of renewal option terms \| Term		2
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, 2020	Dec. 31, 2019	Dec. 31, 2018
Lease Cost [Abstract]
Operating lease cost	$ 6,917	$ 5,155	$ 4,503

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information Related to the Company's Leases (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 4,480	$ 4,841
Right-of-use assets obtained in exchange for operating lease obligations:	$ 42,039	$ 13,399

Leases - Summary of Balance She

Leases - Summary of Balance Sheet Classification of Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Operating lease liabilities
Current portion of lease liabilities	$ 5,087	$ 3,434
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesCurrent	us-gaap:AccruedLiabilitiesCurrent
Operating lease liabilities	$ 44,460	$ 6,361
Total operating lease liabilities	$ 49,547	$ 9,795

Leases - Summary of Maturities

Leases - Summary of Maturities of Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Operating Lease Liabilities [Abstract]
2021	$ 5,284
2022	7,193
2023	6,635
2024	6,397
2025	5,922
Thereafter	29,762
Total lease payments	61,193
Less:
Imputed interest	(11,646)
Total operating lease liabilities	$ 49,547	$ 9,795

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. 30, 2020		Sep. 30, 2020		Jun. 30, 2020		Mar. 31, 2020		Dec. 31, 2019		Sep. 30, 2019		Jun. 30, 2019		Mar. 31, 2019		Dec. 31, 2020		Dec. 31, 2019		Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Revenues		$ 121,007		$ 120,577		$ 110,103		$ 90,068		$ 98,326		$ 94,586		$ 83,205		$ 62,959		$ 441,755		$ 339,076
Gross profit	[1]	118,499		118,572		107,204		87,269		95,306		92,170		80,247		60,009		431,544		327,732
Net loss		$ (66,760)		$ (84,660)		$ (42,141)		$ (88,023)		$ (53,036)		$ (41,978)		$ (54,941)		$ (85,304)		$ (281,584)		$ (235,259)		$ (245,192)
Basic and diluted net loss per share		$ (0.42)	[2]	$ (0.05)	[2]	$ (0.27)	[2]	$ (0.57)	[2]	$ (0.34)	[2]	$ (0.29)	[2]	$ (0.38)	[2]	$ (0.59)	[2]	$ (1.79)	[2]	$ (1.60)	[2]	$ (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.

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, 2020	Dec. 31, 2019	Dec. 31, 2018
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period	$ 2,576	$ 1,840	$ 246
Additions, Provision Related to Current Period Sales	51,684	33,827	24,613
Deductions, Actual Distribution Fees, Discounts and Chargebacks Related to Current Period Sales	(47,463)	(31,251)	(22,773)
Deductions, Actual Distribution Fees, Discounts and Chargebacks Related to Prior Period Sales	(2,576)	(1,840)	(246)
Balance at End of Period	$ 4,221	$ 2,576	$ 1,840