ACADIA Pharmaceuticals (ACAD) 10-Q 8 May 20 2020 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2020	Apr. 22, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Trading Symbol	ACAD
Entity Registrant Name	ACADIA PHARMACEUTICALS INC.
Entity Central Index Key	0001070494
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		155,724,104
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	000-50768
Entity Tax Identification Number	06-1376651
Entity Interactive Data Current	Yes
Document Quarterly Report	true
Document Transition Report	false
Entity Address, Address Line One	3611 Valley Centre Drive, Suite 300
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92130
City Area Code	858
Local Phone Number	558-2871
Entity Incorporation, State or Country Code	DE
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Security Exchange Name	NASDAQ

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Assets
Cash and cash equivalents	$ 173,059	$ 189,680
Investment securities, available-for-sale	478,347	507,749
Accounts receivable, net	41,636	35,781
Interest and other receivables	2,935	2,093
Inventory	6,318	6,341
Prepaid expenses	22,126	18,606
Total current assets	724,421	760,250
Property and equipment, net	5,089	3,180
Operating lease right-of-use assets	8,613	9,524
Intangible assets, net	2,215	2,585
Restricted cash	5,770	4,787
Other assets	1,342	2,857
Total assets	747,450	783,183
Liabilities and stockholders’ equity
Accounts payable	6,623	7,222
Accrued liabilities	93,118	67,604
Total current liabilities	99,741	74,826
Operating lease liabilities	6,090	6,361
Other long-term liabilities	3,237	2,861
Total liabilities	109,068	84,048
Commitments and contingencies (Note 9)
Stockholders’ equity:
Preferred stock, $0.0001 par value; 5,000,000 shares authorized at March 31, 2020 and December 31, 2019; no shares issued and outstanding at March 31, 2020 and December 31, 2019
Common stock, $0.0001 par value; 225,000,000 shares authorized at March 31, 2020 and December 31, 2019; 155,441,052 shares and 155,275,300 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively	15	15
Additional paid-in capital	2,428,987	2,402,945
Accumulated deficit	(1,792,145)	(1,704,122)
Accumulated other comprehensive income	1,525	297
Total stockholders’ equity	638,382	699,135
Total liabilities and stockholders’ equity	$ 747,450	$ 783,183

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 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	155,441,052	155,275,300
Common stock, shares outstanding	155,441,052	155,275,300

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenues
Type of Revenue [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember
Total revenues	$ 90,068	$ 62,959
Operating expenses
Type of Cost, Good or Service [Extensible List]	us-gaap:ProductMember	us-gaap:ProductMember
Cost of product sales	$ 2,799	$ 2,950
License fees and royalties	2,175	1,630
Research and development	72,636	52,923
Selling, general and administrative	101,973	93,090
Total operating expenses	179,583	150,593
Loss from operations	(89,515)	(87,634)
Interest income, net	2,989	2,934
Other expense	(1,497)	(229)
Loss before income taxes	(88,023)	(84,929)
Income tax expense		375
Net loss	$ (88,023)	$ (85,304)
Net loss per common share, basic and diluted	$ (0.57)	$ (0.59)
Weighted average common shares outstanding, basic and diluted	155,368	143,981

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (88,023)	$ (85,304)
Other comprehensive income:
Unrealized gain on investment securities	1,226	577
Foreign currency translation adjustments	2	2
Comprehensive loss	$ (86,795)	$ (84,725)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities
Net loss	$ (88,023)	$ (85,304)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	22,348	19,883
Amortization of premiums and accretion of discounts on investment securities	87	(1,006)
Amortization of intangible assets	370	370
Loss on strategic investment	1,497	229
Depreciation	294	415
Changes in operating assets and liabilities:
Accounts receivable, net	(5,855)	(3,868)
Interest and other receivables	(842)	(2,113)
Inventory	(37)	(557)
Prepaid expenses	(3,520)	(3,015)
Operating lease right-of-use assets	1,187	833
Other assets	18	105
Accounts payable	(599)	108
Accrued liabilities	24,057	11,035
Operating lease liabilities	(360)	(938)
Long-term liabilities	376	(352)
Net cash used in operating activities	(49,002)	(64,175)
Cash flows from investing activities
Purchases of investment securities	(100,773)	(73,945)
Maturities of investment securities	131,315	97,525
Purchases of property and equipment	(934)	(822)
Net cash provided by investing activities	29,608	22,758
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs	3,754	4,176
Net cash provided by financing activities	3,754	4,176
Effect of exchange rate changes on cash	2	1
Net decrease in cash, cash equivalents and restricted cash	(15,638)	(37,240)
Cash, cash equivalents and restricted cash
Beginning of period	194,467	139,584
End of period	178,829	102,344
Supplemental disclosure of noncash information:
Property and equipment purchases in accounts payable and accrued liabilities	$ 1,269	$ 21

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2018	$ 479,079	$ 14	$ 1,948,300	$ (1,468,863)	$ (372)
Issuance of common stock from exercise of stock options			4,176
Stock-based compensation			19,826
Net loss	(85,304)			(85,304)
Ending balance at Mar. 31, 2019	418,356	14	1,972,302	(1,554,167)	207
Other comprehensive (loss) income	579
Beginning balance at Dec. 31, 2019	699,135	15	2,402,945	(1,704,122)	297
Issuance of common stock from exercise of stock options			3,754
Stock-based compensation			22,288
Net loss	(88,023)			(88,023)
Ending balance at Mar. 31, 2020	638,382	$ 15	$ 2,428,987	$ (1,792,145)	$ 1,525
Other comprehensive (loss) income	$ 1,228

Organization and Business

Organization and Business	3 Months Ended
	Mar. 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 ®

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	2. Basis of Presentation and Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company should be read in conjunction with the audited financial statements and notes thereto as of and for the year ended December 31, 2019 included in the Company’s Annual Report on Form 10-K (“Annual Report”) filed with the Securities and Exchange Commission (the “SEC”). The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, since they are interim statements, the accompanying financial statements do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, the accompanying financial statements reflect all adjustments (consisting of normal recurring adjustments) that are necessary for a fair statement of the financial position, results of operations, cash flows, and stockholders’ equity for the interim periods presented. Interim results are not necessarily indicative of results for a full year. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and the accompanying notes. Actual results could differ from those estimates . Risk and The global pandemic resulting from the disease known as COVID-19, caused by a novel strain of coronavirus, SARS-CoV-2, has caused national and global economic and financial market disruptions and may adversely impact our business. Although the Company did not see a material impact on its net revenue in the first quarter of 2020 due to the COVID-19 pandemic, the Company cannot predict the duration or magnitude of the pandemic or the have on . During the three months ended March 31, 2020, there have been no changes to the Company’s significant accounting policies as described in its Annual Report on Form 10-K for the fiscal year ended December 31, 2019, except as described below and in Note 6, investments . Cash, Cash Equivalents and Restricted Cash The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the statement of cash flows that sum to the total of the same such amounts shown in the statement of cash flows (in thousands): March 31, 2020 March 31, 2019 Beginning of period End of period Beginning of period End of period Cash and cash equivalents $ 189,680 $ 173,059 $ 134,758 $ 97,557 Restricted cash 4,787 5,770 4,826 4,787 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 194,467 $ 178,829 $ 139,584 $ 102,344 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. As described further in Note 10, Recent Accounting Pronouncements, 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. 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 $0.4 million for each of the three months ended March 31, 2020 and 2019, respectively. As of March 31, 2020, estimated future amortization expense related to the Company’s intangible asset was $1.1 million for the remainder of 2020 and $1.1 million for 2021. Royalties incurred in connection with the Company’s license agreement with the Ipsen Group, as disclosed in Note 9, Commitments and Contingencies,

Net Loss Per Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2020
Earnings Per Share [Abstract]
Net Loss Per Share	3. 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 plan rights, restricted stock units, 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 anti-dilutive. The Company incurred net losses for all periods presented and there were no reconciling items for potentially dilutive securities .

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	4. Stock-Based Compensation The following table summarizes the total stock-based compensation expense included in the Company’s statements of operations for the periods presented (in thousands): Three Months Ended March 31, 2020 2019 Cost of product sales $ 849 $ 995 Research and development 8,457 7,880 Selling, general and administrative 13,042 11,008 $ 22,348 $ 19,883

Balance Sheet Details

Balance Sheet Details	3 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Balance Sheet Details	5. Balance Sheet Details Inventory consisted of the following (in thousands): March 31, 2020 December 31, 2019 Raw material $ 2,907 $ 3,175 Work in process 988 1,685 Finished goods 2,423 1,481 $ 6,318 $ 6,341 Accrued liabilities consisted of the following (in thousands): March 31, 2020 December 31, 2019 Accrued sales allowances $ 27,581 11,326 Accrued consulting and professional fees 21,711 13,691 Accrued research and development services 16,433 14,273 Accrued compensation and benefits 16,030 21,080 Accrued royalties 3,776 1,971 Current portion of lease liabilities 2,909 3,434 Other 4,678 1,829 $ 93,118 $ 67,604

Investments

Investments	3 Months Ended
	Mar. 31, 2020
Investments Debt And Equity Securities [Abstract]
Investments	6. Investments The carrying value and amortized cost of the Company’s investments, summarized by major security type, consisted of the following (in thousands): March 31, 2020 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value U.S. Treasury notes $ 238,541 $ 1,588 $ — $ 240,129 Government sponsored enterprise securities 71,030 292 — 71,322 Corporate debt securities 112,075 74 (491 ) 111,658 Commercial paper 55,204 40 (6 ) 55,238 $ 476,850 $ 1,994 $ (497 ) $ 478,347 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 March 31, 2020 and December 31, 2019, the Company held $3.0 million and $24.3 million, respectively, of available-for-sale investment securities with contractual maturity dates of more than one year and less than two years. The Company has classified all equity securities as other assets on its Consolidated Balance Sheets. At March 31, 2020 and December 31, 2019, the Company had 21 and 20 available-for-sale investment securities, respectively, in an unrealized loss position. The following table presents gross unrealized losses and fair value for those available-for-sale investment securities that were in an unrealized loss position as of March 31, 2020 and December 31, 2019, aggregated by investment category and length of time that the 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 March 31, 2020: Corporate debt securities $ 89,774 $ (491 ) $ — $ — $ 89,774 $ (491 ) Commercial paper 24,806 (6 ) — — 24,806 (6 ) Total $ 114,580 $ (497 ) $ — $ — $ 114,580 $ (497 ) Less Than 12 Months 12 Months or Greater Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses December 31, 2019: U.S. Treasury notes $ 148,397 $ (13 ) $ — $ — $ 148,397 $ (13 ) Government sponsored enterprise securities 61,103 (30 ) — — 61,103 (30 ) Corporate debt securities 11,334 (8 ) — — 11,334 (8 ) Total $ 220,834 $ (51 ) $ — $ — $ 220,834 $ (51 ) As described further in Note 10, Recent Accounting Pronouncements Financial Instruments – Credit Losses The Company does not intend to sell the investments in unrealized loss position and it is unlikely that the Company will be required to sell the investments before the recovery of their 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 March 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	3 Months Ended
	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	7. 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 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 March 31, 2020 and December 31, 2019. 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 March 31, 2020 and December 31, 2019 consisted of the following (in thousands): Fair Value Measurements at Reporting Date Using March 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 $ 139,886 $ 139,886 $ — $ — U.S. Treasury notes 251,128 251,128 — — Equity securities 810 810 — — Government sponsored enterprise securities 71,322 — 71,322 — Corporate debt securities 111,658 — 111,658 — Commercial paper 55,238 — 55,238 — $ 630,042 $ 391,824 $ 238,218 $ — 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 — — Equity securities 2,307 2,307 — — Government sponsored enterprise securities 103,878 — 103,878 — Corporate debt securities 88,039 — 88,039 — Commercial paper 102,212 — 102,212 — $ 623,123 $ 328,994 $ 294,129 $ —

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2020
Equity [Abstract]
Stockholders' Equity	8. Stockholders’ Equity Public Offerings In September 2019, the Company raised net proceeds of approximately $271.5 million from the sale of 7,187,500 shares of its common stock in a follow-on public offering, including 937,500 shares sold pursuant to the exercise in full of the underwriters’ option to purchase additional shares. In November 2018, the Company raised net proceeds of approximately $298.5 million from the sale of 18,602,941 shares of its common stock in a follow-on public offering, including 2,426,470 shares sold pursuant to the exercise in full of the underwriters’ option to purchase additional shares. In August 2016, the Company raised net proceeds of approximately $215.9 million from the sale of 6,969,696 shares of its common stock in a follow-on public offering, including 909,090 shares sold pursuant to the exercise in full of the underwriters’ option to purchase additional shares. In January 2016, the Company raised net proceeds of approximately $281.6 million from the sale of 10,344,827 shares of its common stock in a follow-on public offering. In connection with the January 2016 offering, the Company entered into a registration rights agreement (the “Registration Rights Agreement”) with 667, L.P., Baker Brothers Life Sciences, L.P. and 14159, L.P. (the “Baker Entities”), all of which are existing stockholders of the Company and are affiliated with two of its directors, Julian C. Baker and Dr. Stephen R. Biggar. Under the Registration Rights Agreement, the Company agreed that, if the Baker Entities demand that the Company register their shares of its common stock for resale under the Securities Act of 1933, as amended (the “Securities Act”), the Company would be obligated to effect such registration. The Company’s registration obligations under the Registration Rights Agreement cover all shares of its common stock now held or later acquired by the Baker Entities (including approximately $75.0 million, $43.0 million, $200.0 million, and $62.5 million of shares that the Baker Entities purchased at the public offering price in the January 2016, August 2016, November 2018, and September 2019 offerings, respectively), will continue in effect for up to 10 years, and include the Company’s obligation to facilitate certain underwritten public offerings of its common stock by the Baker Entities in the future. The Company has agreed to bear all expenses incurred by it in effecting any registration pursuant to the Registration Rights Agreement as well as the legal expenses of the Baker Entities of up to $50,000 per underwritten public offering effected pursuant to the Registration Rights Agreement. pursuant to the Registration Rights Agreement, Private Equity Financings In December 2012, the Company raised net proceeds of $80.5 million through the sale of 19,000,000 shares of its common stock at a price of $4.43 per share and the sale of warrants to purchase 500,000 shares of its common stock at a price of $4.42 per warrant share in a private equity financing. The warrants have an exercise price of $0.01 per share. In accordance with authoritative accounting guidance, the warrants’ value of $2.2 million was determined on the date of grant using the Black-Scholes model and recorded as a component of stockholders’ equity within additional paid-in capital. Per their terms, the warrants to purchase 500,000 shares of common stock, of which 493,145 remained outstanding at March 31, 2020, may not be exercised if the holder’s ownership of the Company’s common stock would exceed 19.99 percent following such exercise.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 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 two percent of net sales of NUPLAZID. This obligation terminates in 2021. License Agreements In May 2018, the Company signed an Exclusivity Deed (the “Deed”) with Neuren Pharmaceuticals Limited (“Neuren”) that provided for exclusive negotiations for a period of three months from the date of the Deed. Under the terms of the Deed, the Company paid $3.1 million to purchase 1,330,000 shares of Neuren and paid $0.9 million for the exclusive right to negotiate a deal with Neuren, which was recorded in selling, general and administrative expenses in the second quarter of 2018. At March 31, 2020, the Company continues to hold the equity securities as a strategic investment in which the Company does not have a controlling interest or significant influence. Publicly held equity securities are measured using quoted prices in their respective active markets with changes recorded through other expense on the statements of operations. Net loss on strategic investments recognized in other expense in the Condensed Consolidated Statements of Operations was $1.5 million and $0.2 million for the three months ended March 31, 2020 and 2019, respectively. The aggregate carrying amount of the Company’s strategic equity investment was $0.8 million and $2.3 million included in other assets on its Condensed Consolidated Balance Sheets at March 31, 2020 and December 31, 2019, respectively. 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, the Company paid Neuren an upfront license fee of $10.0 million and it may be required to pay up to an additional $455.0 million in milestone payments based on the achievement of certain development and annual net sales milestones. In addition, the Company may be required to pay Neuren 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 expensed to research and development 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 $ million and may be required to pay up to $ 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 year s 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 20 20 as there is no future alternative use for the asset s . Corporate Credit Card Program In connection with the Company’s credit card program, the Company established a letter of credit 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 Between July 19 and August 3, 2018, following negative publicity about NUPLAZID, three purported company stockholders filed putative securities class action complaints (captioned Staublein v. ACADIA Pharmaceuticals, Inc., Case No. 18-cv-01647, Stone v. ACADIA Pharmaceuticals Inc., Case No. 18-cv-01672, and Barglow v. ACADIA Pharmaceuticals Inc., Case No. 18-cv-01812) in the U.S. District Court for the Southern District of California against the Company and certain of its current and former executive officers. Thereafter, several putative lead plaintiffs filed motions to consolidate the cases and to appoint a lead plaintiff. On January 3, 2019, the Court consolidated the cases under the caption In re ACADIA Pharmaceuticals Inc. Securities Litigation, Case No. 18-cv-01647, and took the lead plaintiff motions under submission. On February 26, 2019, the Court appointed a lead plaintiff and lead counsel. Lead plaintiff filed a consolidated complaint on April 15, 2019. The consolidated complaint generally alleges that defendants violated Sections 10(b) and 20(a) of the Securities Exchange Act of 1934 by making materially false and misleading statements regarding the Company’s business, operations, and prospects by failing to disclose that adverse events and safety concerns regarding NUPLAZID threatened initial and continuing FDA approval, and by failing to disclose that the Company engaged in business practices likely to attract regulatory scrutiny. The consolidated complaint seeks unspecified monetary damages and other relief. Defendants filed a motion to dismiss the consolidated complaint on June 7, 2019 and the lead plaintiff filed an opposition on July 23, 2019. Defendants filed a reply on August 22, 2019. On November 12, 2019, the Court determined that the motion to dismiss was suitable for resolution without oral argument and took the motion hearing off calendar On February 7, 2020, a purported company stockholder filed a derivative complaint (captioned Barney v. Davis et al., Case No. 20-cv-0238) in the U.S. District Court for the Southern District of California against the Company’s directors and certain of its current and former executive officers. The complaint asserts claims for breach of fiduciary duty, waste of corporate assets, and unjust enrichment arising from allegations similar to those in the federal securities class action described above. On February 19, 2020, the Court granted the parties’ stipulation to stay the derivative action pending a ruling on the motion to dismiss in the federal securities class action. Given the unpredictability inherent in litigation, 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 is cooperating with the DOJ’s request. Responding to the CID will require considerable resources and no assurance can be given as to the timing or outcome of the DOJ’s investigation.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	3 Months Ended
	Mar. 31, 2020
New Accounting Pronouncements And Changes In Accounting Principles [Abstract]
Recent Accounting Pronouncements	10. Recent Accounting Pronouncements In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“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 The Company adopted the above standards on January 1, 2020. The adoption of the new standards did not have a material impact 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

Leases

Leases	3 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Leases	11. Leases The Company leases facilities and certain equipment under noncancelable operating leases with remaining lease terms of 0.1 year to 5.8 years, one of which includes an option to extend the lease for one five-year The operating lease costs were as follows (in thousands): Three Months Ended March 31, 2020 2019 Operating lease cost $ 1,487 $ 1,275 Supplemental cash flow information related to the Company’s leases were as follows (in thousands): Three Months Ended March 31, 2020 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 1,291 $ 1,102 Right-of-use assets obtained in exchange for operating lease obligations: 276 11,751 The balance sheet classification of the Company’s lease liabilities was as follows (in thousands): March 31, 2020 December 31, 2019 Operating lease liabilities Current portion included in accrued liabilities $ 2,909 $ 3,434 Operating lease liabilities 6,090 6,361 Total operating lease liabilities $ 8,999 $ 9,795 Maturities of lease liabilities were as follows (in thousands): Operating Leases Remainder of 2020 $ 2,338 Years ending December 31, 2021 2,720 2022 2,179 2023 1,317 2024 1,090 Thereafter 1,011 Total lease payments 10,655 Less: Imputed interest (1,656 ) Total operating lease liabilities $ 8,999 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 March 31, 2020, the weighted average remaining lease term is 4.9 years and the weighted average discount rate used to determine the operating lease liability was 8.0%. In the fourth quarter of 2018, the Company entered into an agreement to lease approximately 67,020 square feet of corporate office space in San Diego, California with total minimum lease payments of $50.4 million over an initial term of 10 years and 9 months. In February 2020, the Company entered into the first amendment to this lease agreement to lease approximately 30,608 square feet of additional corporate office space in San Diego, with total minimum lease payments of $25.3 million over an initial term of approximately 10 years and 7 months. In March 2020, the Company entered into the second amendment to the lease agreement which increased the total minimum lease payments of the original 67,020 square feet of corporate office space to $51.4 million. As

Basis of Presentation and Sig_2

Basis of Presentation and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company should be read in conjunction with the audited financial statements and notes thereto as of and for the year ended December 31, 2019 included in the Company’s Annual Report on Form 10-K (“Annual Report”) filed with the Securities and Exchange Commission (the “SEC”). The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) for interim financial information and in accordance with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, since they are interim statements, the accompanying financial statements do not include all of the information and notes required by GAAP for complete financial statements. In the opinion of management, the accompanying financial statements reflect all adjustments (consisting of normal recurring adjustments) that are necessary for a fair statement of the financial position, results of operations, cash flows, and stockholders’ equity for the interim periods presented. Interim results are not necessarily indicative of results for a full year. The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and the accompanying notes. Actual results could differ from those estimates .
Risk and Uncertainties	Risk and The global pandemic resulting from the disease known as COVID-19, caused by a novel strain of coronavirus, SARS-CoV-2, has caused national and global economic and financial market disruptions and may adversely impact our business. Although the Company did not see a material impact on its net revenue in the first quarter of 2020 due to the COVID-19 pandemic, the Company cannot predict the duration or magnitude of the pandemic or the have on .
Cash, Cash Equivalents and Restricted Cash	Cash, Cash Equivalents and Restricted Cash The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the statement of cash flows that sum to the total of the same such amounts shown in the statement of cash flows (in thousands): March 31, 2020 March 31, 2019 Beginning of period End of period Beginning of period End of period Cash and cash equivalents $ 189,680 $ 173,059 $ 134,758 $ 97,557 Restricted cash 4,787 5,770 4,826 4,787 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 194,467 $ 178,829 $ 139,584 $ 102,344
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. As described further in Note 10, Recent Accounting Pronouncements, 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.
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 $0.4 million for each of the three months ended March 31, 2020 and 2019, respectively. As of March 31, 2020, estimated future amortization expense related to the Company’s intangible asset was $1.1 million for the remainder of 2020 and $1.1 million for 2021. Royalties incurred in connection with the Company’s license agreement with the Ipsen Group, as disclosed in Note 9, Commitments and Contingencies,
Recent Accounting Pronouncements	In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“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 The Company adopted the above standards on January 1, 2020. The adoption of the new standards did not have a material impact 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

Basis of Presentation and Sig_3

Basis of Presentation and Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 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 within the statement of cash flows that sum to the total of the same such amounts shown in the statement of cash flows (in thousands): March 31, 2020 March 31, 2019 Beginning of period End of period Beginning of period End of period Cash and cash equivalents $ 189,680 $ 173,059 $ 134,758 $ 97,557 Restricted cash 4,787 5,770 4,826 4,787 Total cash, cash equivalents and restricted cash shown in the statement of cash flows $ 194,467 $ 178,829 $ 139,584 $ 102,344

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock-based Compensation Expense Included in Statements of Operations	The following table summarizes the total stock-based compensation expense included in the Company’s statements of operations for the periods presented (in thousands): Three Months Ended March 31, 2020 2019 Cost of product sales $ 849 $ 995 Research and development 8,457 7,880 Selling, general and administrative 13,042 11,008 $ 22,348 $ 19,883

Balance Sheet Details (Tables)

Balance Sheet Details (Tables)	3 Months Ended
	Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Schedule of Inventory	Inventory consisted of the following (in thousands): March 31, 2020 December 31, 2019 Raw material $ 2,907 $ 3,175 Work in process 988 1,685 Finished goods 2,423 1,481 $ 6,318 $ 6,341
Schedule of Accrued Liabilities	Accrued liabilities consisted of the following (in thousands): March 31, 2020 December 31, 2019 Accrued sales allowances $ 27,581 11,326 Accrued consulting and professional fees 21,711 13,691 Accrued research and development services 16,433 14,273 Accrued compensation and benefits 16,030 21,080 Accrued royalties 3,776 1,971 Current portion of lease liabilities 2,909 3,434 Other 4,678 1,829 $ 93,118 $ 67,604

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 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): March 31, 2020 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value U.S. Treasury notes $ 238,541 $ 1,588 $ — $ 240,129 Government sponsored enterprise securities 71,030 292 — 71,322 Corporate debt securities 112,075 74 (491 ) 111,658 Commercial paper 55,204 40 (6 ) 55,238 $ 476,850 $ 1,994 $ (497 ) $ 478,347 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 investment securities that were in an unrealized loss position as of March 31, 2020 and December 31, 2019, aggregated by investment category and length of time that the 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 March 31, 2020: Corporate debt securities $ 89,774 $ (491 ) $ — $ — $ 89,774 $ (491 ) Commercial paper 24,806 (6 ) — — 24,806 (6 ) Total $ 114,580 $ (497 ) $ — $ — $ 114,580 $ (497 ) Less Than 12 Months 12 Months or Greater Total Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses Estimated Fair Value Unrealized Losses December 31, 2019: U.S. Treasury notes $ 148,397 $ (13 ) $ — $ — $ 148,397 $ (13 ) Government sponsored enterprise securities 61,103 (30 ) — — 61,103 (30 ) Corporate debt securities 11,334 (8 ) — — 11,334 (8 ) Total $ 220,834 $ (51 ) $ — $ — $ 220,834 $ (51 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 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 March 31, 2020 and December 31, 2019 consisted of the following (in thousands): Fair Value Measurements at Reporting Date Using March 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 $ 139,886 $ 139,886 $ — $ — U.S. Treasury notes 251,128 251,128 — — Equity securities 810 810 — — Government sponsored enterprise securities 71,322 — 71,322 — Corporate debt securities 111,658 — 111,658 — Commercial paper 55,238 — 55,238 — $ 630,042 $ 391,824 $ 238,218 $ — 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 — — Equity securities 2,307 2,307 — — Government sponsored enterprise securities 103,878 — 103,878 — Corporate debt securities 88,039 — 88,039 — Commercial paper 102,212 — 102,212 — $ 623,123 $ 328,994 $ 294,129 $ —

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2020
Leases [Abstract]
Summary of Operating Lease Costs	The operating lease costs were as follows (in thousands): Three Months Ended March 31, 2020 2019 Operating lease cost $ 1,487 $ 1,275
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): Three Months Ended March 31, 2020 2019 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 1,291 $ 1,102 Right-of-use assets obtained in exchange for operating lease obligations: 276 11,751
Summary of Balance Sheet Classification of Lease Liabilities	The balance sheet classification of the Company’s lease liabilities was as follows (in thousands): March 31, 2020 December 31, 2019 Operating lease liabilities Current portion included in accrued liabilities $ 2,909 $ 3,434 Operating lease liabilities 6,090 6,361 Total operating lease liabilities $ 8,999 $ 9,795
Summary of Maturities of Lease Liabilities	Maturities of lease liabilities were as follows (in thousands): Operating Leases Remainder of 2020 $ 2,338 Years ending December 31, 2021 2,720 2022 2,179 2023 1,317 2024 1,090 Thereafter 1,011 Total lease payments 10,655 Less: Imputed interest (1,656 ) Total operating lease liabilities $ 8,999

Basis of Presentation and Sig_4

Basis of Presentation and Significant Accounting Policies - Schedule of Reconciliation of Cash, Cash Equivalents and Restricted Cash (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations [Abstract]
Cash and cash equivalents	$ 173,059	$ 189,680	$ 97,557	$ 134,758
Restricted cash	5,770	4,787	4,787	4,826
Total cash, cash equivalents and restricted cash shown in the statement of cash flows	$ 178,829	$ 194,467	$ 102,344	$ 139,584

Basis of Presentation and Sig_5

Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Apr. 30, 2016	Mar. 31, 2020	Mar. 31, 2019
Accounting Policies [Abstract]
One-time contingent regulatory milestone payment pursuant to agreement with Ipsen Group	$ 8,000
Finite-lived intangible assets, net	$ 8,000
Amortization of intangible assets		$ 370	$ 370
Estimated future amortization expense, remainder of 2020		1,100
Estimated future amortization expense, 2021		$ 1,100

Net Loss Per Share - Additional

Net Loss Per Share - Additional Information (Detail) - shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share [Abstract]
Antidilutive securities to purchase common stock	21,064,000	20,623,000

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock-based Compensation Expense Included in Statements of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 22,348	$ 19,883
Cost of product sales
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	849	995
Research and development
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	8,457	7,880
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 13,042	$ 11,008

Balance Sheet Details - Schedul

Balance Sheet Details - Schedule of Inventory (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw material	$ 2,907	$ 3,175
Work in process	988	1,685
Finished goods	2,423	1,481
Inventory	$ 6,318	$ 6,341

Balance Sheet Details - Sched_2

Balance Sheet Details - Schedule of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Payables And Accruals [Abstract]
Accrued sales allowances	$ 27,581	$ 11,326
Accrued consulting and professional fees	21,711	13,691
Accrued research and development services	16,433	14,273
Accrued compensation and benefits	16,030	21,080
Accrued royalties	3,776	1,971
Current portion of lease liabilities	2,909	3,434
Other	4,678	1,829
Accrued liabilities	$ 93,118	$ 67,604

Investments - Carrying Value an

Investments - Carrying Value and Amortized Cost of Company's Investments Summarized by Major Security Type (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Estimated Fair Value	$ 478,347	$ 507,749
Equity securities, Amortized Cost	476,850
Equity securities, Unrealized Gains	1,994
Equity securities, Unrealized Losses	(497)
Equity securities, Estimated Fair Value	478,347
Debt and equity securities, Amortized Cost	476,850	507,465
Debt and equity securities, Unrealized Gains	1,994	335
Debt and equity securities, Unrealized Losses	(497)	(51)
Debt and equity securities, Estimated Fair Value	478,347	507,749
US Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Debt securities, Amortized Cost	238,541	228,609
Debt securities, Unrealized Gains	1,588	7
Debt securities, Unrealized Losses		(13)
Debt securities, Estimated Fair Value	240,129	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	71,030	88,920
Debt securities, Unrealized Gains	292	5
Debt securities, Unrealized Losses		(30)
Debt securities, Estimated Fair Value	71,322	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	112,075	87,785
Debt securities, Unrealized Gains	74	262
Debt securities, Unrealized Losses	(491)	(8)
Debt securities, Estimated Fair Value	111,658	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	55,204	102,151
Debt securities, Unrealized Gains	40	61
Debt securities, Unrealized Losses	(6)
Debt securities, Estimated Fair Value	$ 55,238	102,212
Equity securities, Amortized Cost		102,151
Equity securities, Unrealized Gains		61
Equity securities, Estimated Fair Value		$ 102,212

Investments - Additional Inform

Investments - Additional Information (Detail) $ in Millions	Mar. 31, 2020USD ($)Security	Dec. 31, 2019USD ($)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 | $	$ 3	$ 24.3
Number of available-for-sale investment securities in unrealized loss position | Security	21	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	Mar. 31, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	$ 114,580	$ 220,834
Less Than 12 Months, Unrealized Losses	(497)	(51)
Total, Estimated Fair Value	114,580	220,834
Total, Unrealized Losses	(497)	(51)
Corporate debt securities
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	89,774	11,334
Less Than 12 Months, Unrealized Losses	(491)	(8)
Total, Estimated Fair Value	89,774	11,334
Total, Unrealized Losses	(491)	(8)
Commercial paper
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value	24,806
Less Than 12 Months, Unrealized Losses	(6)
Total, Estimated Fair Value	24,806
Total, Unrealized Losses	$ (6)
US Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value		148,397
Less Than 12 Months, Unrealized Losses		(13)
Total, Estimated Fair Value		148,397
Total, Unrealized Losses		(13)
US Government Sponsored Enterprises Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Less Than 12 Months, Estimated Fair Value		61,103
Less Than 12 Months, Unrealized Losses		(30)
Total, Estimated Fair Value		61,103
Total, Unrealized Losses		$ (30)

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	Mar. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	$ 630,042	$ 623,123
Money market fund
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	139,886	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	391,824	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	139,886	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	238,218	294,129
U.S. Treasury notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	251,128	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	251,128	228,603
Equity securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	810	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	810	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	71,322	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	71,322	103,878
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	111,658	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	111,658	88,039
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments, fair value disclosure	55,238	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	$ 55,238	$ 102,212

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	1 Months Ended					3 Months Ended
	Sep. 30, 2019	Nov. 30, 2018	Aug. 31, 2016	Jan. 31, 2016	Dec. 31, 2012	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Class of Stock [Line Items]
Net proceeds from sale of common stock	$ 271,500,000	$ 298,500,000	$ 215,900,000	$ 281,600,000		$ 3,754,000	$ 4,176,000
Share of common stock issued	7,187,500	18,602,941	6,969,696	10,344,827	19,000,000
Value of shares purchased by Baker Entities in public offerings						$ 15,000		$ 15,000
Proceed from sale of stock and warrants					$ 80,500,000
Common stock sale price per share					$ 4.43
Expire on December 17, 2019
Class of Stock [Line Items]
Warrants issued					500,000
Warrants issuance price per share					$ 4.42
Warrant exercise price					$ 0.01
Issuance of warrant value					$ 2,200,000
Warrants outstanding					500,000	493,145
Description of warrant						Per their terms, the warrants to purchase 500,000 shares of common stock, of which 493,145 remained outstanding at March 31, 2020, may not be exercised if the holder’s ownership of the Company’s common stock would exceed 19.99 percent following such exercise.
Registration Rights Agreement
Class of Stock [Line Items]
Expiration period				10 years
Maximum amount of expense agreed to bear under the agreement				$ 50,000
Registration Rights Agreement | Baker Brothers Life Sciences L.P.
Class of Stock [Line Items]
Value of shares purchased by Baker Entities in public offerings	$ 62,500,000	$ 200,000,000	$ 43,000,000	$ 75,000,000
Option To Purchase Additional Shares
Class of Stock [Line Items]
Share of common stock issued	937,500	2,426,470	909,090

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)	1 Months Ended			3 Months Ended
	Mar. 31, 2020	Aug. 31, 2018	May 31, 2018	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
Other Commitments [Line Items]
Obligation expiration year				2021
Loss on strategic investment				$ 1,497,000	$ 229,000
Restricted cash	$ 5,770,000			5,770,000	4,787,000		$ 4,787,000	$ 4,826,000
Letter of Credit | Corporate Credit Card Program
Other Commitments [Line Items]
Restricted cash	2,000,000			2,000,000
Letter of Credit | Fleet Program
Other Commitments [Line Items]
Restricted cash	400,000			400,000
Other assets
Other Commitments [Line Items]
Aggregate carrying amount of strategic equity investment	800,000			800,000			$ 2,300,000
Other expense
Other Commitments [Line Items]
Loss on strategic investment				1,500,000	$ 200,000
Exclusivity Deed | Neuren
Other Commitments [Line Items]
Aggregate carrying amount of strategic equity investment			$ 3,100,000
Shares subscribed			1,330,000
Exclusivity Deed | Neuren | Selling, general and administrative
Other Commitments [Line Items]
Payments for exclusive right			$ 900,000
License Agreements | Neuren | North America
Other Commitments [Line Items]
Upfront license fee	10,000,000	$ 10,000,000
License Agreements | Neuren | Research and development | North America
Other Commitments [Line Items]
Upfront payment				$ 10,000,000		$ 10,000,000
Maximum
Other Commitments [Line Items]
Percentage of royalty payments obligation on net product sales				2.00%
Maximum | License Agreements | Neuren | North America
Other Commitments [Line Items]
Additional milestone payments payable	$ 515,000,000	$ 455,000,000		$ 515,000,000

Leases - Additional Information

Leases - Additional Information (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2020USD ($)ft²	Feb. 29, 2020USD ($)ft²	Dec. 31, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)ft²
Lessee Lease Description [Line Items]
Operating lease, description	The Company leases facilities and certain equipment under noncancelable operating leases with remaining lease terms of 0.1 year to 5.8 years, one of which includes an option to extend the lease for one five-year term.
Operating lease, option to extend	true
Operating lease, options to extend	one of which includes an option to extend the lease for one five-year term.
Operating lease, renewal term	5 years
Weighted average remaining lease term	4 years 10 months 24 days
Weighted average discount rate	8.00%
Restricted cash	$ 5,770		$ 4,787	$ 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]
Office space leases in square feet | ft²	67,020	30,608			67,020
Minimum lease payment amount	$ 51,400	$ 25,300			$ 50,400
Lease commencement period	third quarter of 2020
Minimum [Member]
Lessee Lease Description [Line Items]
Operating lease remaining lease term	4 days
Maximum
Lessee Lease Description [Line Items]
Operating lease remaining lease term	5 years 29 days

Leases - Summary of Operating L

Leases - Summary of Operating Lease Costs (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Lease Cost [Abstract]
Operating lease cost	$ 1,487	$ 1,275

Leases - Supplemental Cash Flow

Leases - Supplemental Cash Flow Information Related to the Company's Leases (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Lease Cost [Abstract]
Operating cash flows from operating leases	$ 1,291	$ 1,102
Right-of-use assets obtained in exchange for operating lease obligations:	$ 276	$ 11,751

Leases - Summary of Balance She

Leases - Summary of Balance Sheet Classification of Lease Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Current portion of lease liabilities	$ 2,909	$ 3,434
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:AccruedLiabilitiesCurrent	us-gaap:AccruedLiabilitiesCurrent
Operating lease liabilities	$ 6,090	$ 6,361
Total operating lease liabilities	$ 8,999	$ 9,795

Leases - Summary of Maturities

Leases - Summary of Maturities of Lease Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Operating Lease Liabilities [Abstract]
Remainder of 2020	$ 2,338
2021	2,720
2022	2,179
2023	1,317
2024	1,090
Thereafter	1,011
Total lease payments	10,655
Less:
Imputed interest	(1,656)
Total operating lease liabilities	$ 8,999	$ 9,795