Catalyst Pharmaceuticals (CPRX) 10-Q 8 May 24 2024 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2024	May 06, 2024
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Entity Registrant Name	CATALYST PHARMACEUTICALS, INC.
Entity Central Index Key	0001369568
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Filer Category	Large Accelerated Filer
Trading Symbol	CPRX
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Address, State or Province	FL
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, par value $0.001 per share
Security Exchange Name	NASDAQ
Entity Common Stock, Shares Outstanding		118,115,079
Entity Tax Identification Number	76-0837053
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	355 Alhambra Circle
Entity Address, Address Line Two	Suite 801
Entity Address, City or Town	Coral Gables
Entity Address, Postal Zip Code	33134
City Area Code	305
Local Phone Number	420-3200
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	001-33057

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current Assets:
Cash and cash equivalents	$ 310,411	$ 137,636
Accounts receivable, net	60,493	53,514
Inventory	19,953	15,644
Prepaid expenses and other current assets	13,745	12,535
Total current assets	404,602	219,329
Operating lease right-of-use asset	2,440	2,508
Property and equipment, net	1,308	1,195
License and acquired intangibles, net	184,705	194,049
Deferred tax assets, net	38,276	36,544
Investment in equity securities	15,345	16,489
Total assets	646,676	470,114
Current Liabilities:
Accounts payable	10,261	14,795
Accrued expenses and other liabilities	69,305	61,268
Total current liabilities	79,566	76,063
Operating lease liability, net of current portion	3,091	3,188
Other non-current liabilities	2,607	2,982
Total liabilities	85,264	82,233
Commitments and contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.001 par value, 5,000,000 shares authorized: none issued and outstanding at March 31, 2024 and December 31, 2023	0	0
Common stock, $0.001 par value, 200,000,000 shares authorized; 118,029,526 shares and 107,121,549 shares issued and outstanding at March 31, 2024 and December 31, 2023, respectively	118	107
Additional paid-in capital	416,747	266,488
Retained earnings	144,547	121,272
Accumulated other comprehensive income (Note 4)	0	14
Total stockholders' equity	561,412	387,881
Total liabilities and stockholders' equity	$ 646,676	$ 470,114

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Mar. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
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	$ 0.001	$ 0.001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	118,029,526	107,121,549
Common stock, shares outstanding	118,029,526	107,121,549

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Revenues:
Total revenues		$ 98,509	$ 85,366
Operating costs and expenses:
Cost of sales	[1]	12,520	9,946
Research and development		2,581	3,562
Selling, general and administrative	[1]	46,938	29,718
Amortization of intangible assets		9,344	6,531
Total operating costs and expenses		71,383	49,757
Operating income		27,126	35,609
Other income, net		1,963	1,704
Net income before income taxes		29,089	37,313
Income tax provision		5,814	7,745
Net income		$ 23,275	$ 29,568
Net income per share:
Basic		$ 0.2	$ 0.28
Diluted		$ 0.19	$ 0.26
Weighted average shares outstanding:
Basic		116,806,117	105,561,229
Diluted		123,403,626	113,986,129
Net income		$ 23,275	$ 29,568
Other comprehensive income (Note 4):
Unrealized gain (loss) on available-for-sale securities, net of tax of $4 and $5, respectively		(14)	(13)
Comprehensive income		23,261	29,555
Product revenue, net [Member]
Revenues:
Total revenues		98,441	85,304
License and other revenue [Member]
Revenues:
Total revenues		$ 68	$ 62
[1]exclusive of amortization of intangible assets

CONSOLIDATED STATEMENTS OF OP_2

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net of tax impact	$ 4	$ 5

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income [Member]
Beginning Balance at Dec. 31, 2022	$ 300,421	$ 105	$ 250,430	$ 49,862	$ 24
Beginning Balance (shares) at Dec. 31, 2022		105,263,000
Stock-based compensation	2,892		2,892
Exercise of stock options for common stock	1,270	$ 1	1,269
Exercise of stock options for common stock (shares)		548,000
Issuance of common stock upon vesting of restricted stock units, net	(477)		(477)
Issuance of common stock upon vesting of restricted stock units, net (Share)		127,000
Other comprehensive gain (loss)	(13)				(13)
Net income	29,568			29,568
Ending Balance at Mar. 31, 2023	333,661	$ 106	254,114	79,430	11
Ending Balance (shares) at Mar. 31, 2023		105,938,000
Beginning Balance at Dec. 31, 2023	387,881	$ 107	266,488	121,272	14
Beginning Balance (shares) at Dec. 31, 2023		107,122,000
Issuance of common stock, net	140,704	$ 10	140,694
Issuance of common stock, net (shares)		10,000,000
Stock-based compensation	8,248		8,248
Exercise of stock options for common stock	1,522	$ 1	1,521
Exercise of stock options for common stock (shares)		664,000
Issuance of common stock upon vesting of restricted stock units, net	(204)		(204)
Issuance of common stock upon vesting of restricted stock units, net (Share)		244,000
Other comprehensive gain (loss)	(14)				(14)
Net income	23,275			23,275
Ending Balance at Mar. 31, 2024	$ 561,412	$ 118	$ 416,747	$ 144,547	$ 0
Ending Balance (shares) at Mar. 31, 2024		118,030,000

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating Activities:
Net income	$ 23,275	$ 29,568
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation	86	69
Stock-based compensation	8,248	2,892
Amortization of intangible assets	9,344	6,531
Deferred taxes	(1,746)	(1,519)
Accretion of discount	153	0
Reduction in the carrying amount of right-of-use asset	68	64
Acquired inventory samples expensed from asset acquisition	0	130
Change in fair value of equity securities	1,144	0
(Increase) decrease in:
Accounts receivable, net	(6,979)	(22,963)
Inventory	(4,309)	577
Prepaid expenses and other current assets	(1,210)	(191)
Increase (decrease) in:
Accounts payable	(4,534)	(584)
Accrued expenses and other liabilities	8,474	(2,422)
Operating lease liability	(89)	(82)
Net cash provided by (used in) operating activities	31,925	12,070
Investing Activities:
Purchases of property and equipment	(199)	(74)
Payment in connection with asset acquisitions	0	(162,293)
Net cash provided by (used in) investing activities	(199)	(162,367)
Financing Activities:
Payment of employee withholding tax related to stock-based compensation	(204)	(477)
Proceeds from exercise of stock options	1,522	1,270
Payment of liabilities arising from asset acquisition	(973)	(644)
Proceeds from issuance of common stock	141,000	0
Payment of fees in connection with issuance of common stock	(296)	0
Net cash provided by (used in) financing activities	141,049	149
Net increase (decrease) in cash and cash equivalents	172,775	(150,148)
Cash and cash equivalents – beginning of period	137,636	298,395
Cash and cash equivalents – end of period	310,411	148,247
Supplemental disclosures of cash flow information:
Cash paid for interest	65
Non-cash investing and financing activities:
Liabilities arising from asset acquisition	$ 0	$ 1,915

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ 23,275	$ 29,568

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Mar. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Organization and Description of

Organization and Description of Business	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	1. Organization and Description of Business. Catalyst Pharmaceuticals, Inc. and subsidiary (collectively, the Company) is a commercial-stage, patient-centric biopharmaceutical company focused on in-licensing, ® ® ® best-in-class The Company’s New Drug Application (NDA) for FIRDAPSE ® ® ® ® ® On December 17, 2022, the Company entered into an asset purchase agreement with Eisai Co., Ltd. (Eisai) for the acquisition of the U.S. rights to FYCOMPA ® ® ® In July 2023, the Company completed its acquisition from Santhera Pharmaceuticals Holdings (Santhera) of an exclusive license for North America for AGAMREE ® ® ® ® ® Since inception, the Company has devoted substantially all its efforts to business planning, research and development, recruiting management and technical staff, acquiring operating assets, raising capital, and selling its products. The Company has been able to fund its cash needs to date through offerings of its securities and from revenues from sales of its products. See Note 15 (Stockholders’ Equity). Capital Resources Based on forecasts of available cash, the Company believes that it has sufficient resources to support the currently anticipated operations for at least the next 12 months from the date of this report. The Company may raise funds in the future through public or private equity offerings, debt financings, corporate collaborations, governmental research grants or other means. The Company may also seek to raise new capital to fund additional business development activities, even if it has sufficient funds for its planned operations. Any sale by the Company of additional equity or convertible debt securities could result in dilution to the Company’s current stockholders. There can be no assurance that any required additional funding will be available to the Company at all or available on terms acceptable to the Company. Further, to the extent that the Company raises additional funds through collaborative arrangements, it may be necessary to relinquish some rights to the Company’s drug candidates or grant sublicenses on terms that are not favorable to the Company. If the Company is not able to secure additional funding when needed, the Company may have to delay, reduce the scope of, or eliminate one or more research and development programs, which could have an adverse effect on the Company’s business. On January 9, 2024, the Company completed a public offering of 10 million shares of its common stock, raising net proceeds of approximately $140.7 million. The proceeds of the offering will be used to potentially acquire new products and for general corporate purposes. Risks and Uncertainties The Company is subject to risks and uncertainties that could affect its business in unforeseen ways.

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	2. Basis of Presentation and Significant Accounting Policies. a. INTERIM FINANCIAL STATEMENTS. 10-Q In the opinion of management, the accompanying unaudited interim consolidated financial statements of the Company contain all adjustments (consisting of only normal recurring adjustments) necessary to present fairly the financial position of the Company as of the dates and for the periods presented. Accordingly, these consolidated statements should be read in conjunction with the financial statements and notes thereto for the year ended December 31, 2023 included in the 2023 Annual Report on Form 10-K b. PRINCIPLES OF CONSOLIDATION. c. USE OF ESTIMATES. d. CASH AND CASH EQUIVALENTS. The Company primarily invests in high credit-quality instruments in order to obtain higher yields on its cash equivalents. The Company considers all highly liquid instruments, purchased with an original maturity of or less, to be cash equivalents. Cash equivalents consist mainly of money market funds and U.S. Treasuries. The Company has substantially all its cash and cash equivalents deposited in money market accounts with one financial institution. These amounts exceed federally insured limits. e. INVESTMENTS. There were no U.S. Treasuries held at March 31, 2024 and U.S. Treasuries held at December 31, 2023 were classified as available-for-sale non-current The Company records available-for-sale available-for-sale available-for-sale available-for-sale In July 2023, the Company made a strategic equity investment into Santhera by acquiring 1,414,688 of Santhera’s post reverse-split ordinary shares (representing approximately 11.26% of Santhera’s outstanding ordinary shares following the transaction). The investment is denominated in Swiss Francs. The Company has determined that it does not have significant influence over the operations of Santhera and accordingly the investment in Santhera’s ordinary shares is recorded under ASC 321, Equity Securities, with changes in fair value, inclusive of changes resulting from movements in foreign exchange rates, in other income, net in the consolidated statement of operations and comprehensive income. f. ACCOUNTS RECEIVABLE, NET. g. INVENTORY work-in-process first-in, Products that have been approved by the FDA or other regulatory authorities, such as FIRDAPSE ® ® ® ® ® ® The Company evaluates for potential excess inventory by analyzing current and future product demand relative to the remaining product shelf life. The Company builds demand forecasts by considering factors such as, but not limited to, overall market potential, market share, market acceptance, and patient usage. h. PREPAID EXPENSES AND OTHER CURRENT ASSETS. co-pay pre-clinical i. PROPERTY AND EQUIPMENT, NET. three five five j BUSINESS COMBINATIONS AND ASSET ACQUISITIONS 805-50, See Notes 12 (Commitments and Contingencies) and 13 (Agreements) for further discussion on the Company’s exclusive license agreement with Jacobus Pharmaceutical Company, Inc. (Jacobus), for the rights to develop and commercialize RUZURGI ® ASC 805-50. ® ® 805-50. k. INTANGIBLE ASSETS, NET. The Company reviews intangible assets with finite lives for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If indicators of impairment exist, an impairment test is performed to assess the recoverability of the affected assets by determining whether the carrying amount of such assets exceeds the undiscounted expected future cash flows. If the affected assets are deemed not recoverable, the Company would estimate the fair value of the assets and record an impairment loss. l. FAIR VALUE OF FINANCIAL INSTRUMENTS. financial m. FAIR VALUE MEASUREMENTS. Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2 inputs are inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs may include quoted prices for similar assets and liabilities in active markets, as well as inputs that are observable for the asset or liability (other than quoted prices), such as interest rates, foreign exchange rates, and yield curves that are observable at commonly quoted intervals. Level 3 inputs are unobservable inputs for the asset or liability, which are typically based on an entity’s own assumptions, as there is little, if any, related market activity. In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. Fair Value Measurements at Reporting Date Using (in thousands) Balances as of Quoted Prices in Significant Other Significant Cash and cash equivalents: Money market funds $ 280,802 $ 280,802 $ —  $ —  Investment in equity securities: Equity securities $ 15,345 $ 15,345 $ —  $ —  Fair Value Measurements at Reporting Date Using (in thousands) Balances as of Quoted Prices in Significant Other Significant Cash and cash equivalents: Money market funds $ 18,256 $ 18,256 $ —  $ —  U.S. Treasuries $ 94,523 $ 94,523 $ —  $ —  Investment in equity securities: Equity securities $ 16,489 $ 16,489 $ —  $ —  n. OPERATING LEASES. right-of-use non-lease o. SHARE REPURCHASES. The Company accounts for share repurchases by charging the excess of the repurchase price over the repurchased common stock’s par value entirely to retained earnings. All repurchased shares are retired and become authorized but unissued shares. The Company accrues for the shares purchased under the share repurchase plan based on the trade date. The Company may terminate or modify its share repurchase program at any time. p. REVENUE RECOGNITION. Product Revenues: To determine revenue recognition for arrangements that are within the scope of Accounting Standards Codification (ASC) Topic 606 – Revenue from Contracts with Customers (Topic 606), the Company performs the following five steps: (i) identify the contract(s) with a customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract, and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company assesses the goods or services promised within each contract and determines those that are performance obligations by assessing whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. For a complete discussion of accounting for product revenue, see Product Revenue, Net below. The Company also may generate revenues from payments received under collaborative and license agreements. Collaborative and license agreement payments may include nonrefundable fees at the inception of the agreements, contingent payments for specific achievements designated in the agreements, and/or net profit-sharing payments on sales of products resulting from the collaborative and license arrangements. For a complete discussion of accounting for collaborative and licensing arrangements, see Revenues from Collaboration and Licensing Arrangements below. The Company recognizes revenue when its customers obtain title of the promised goods, in an amount that reflects the consideration to which the Company expects to be entitled in exchange for these goods. For FIRDAPSE ® ® ® ® ® ® ® ® During 2023, the Company sold FYCOMPA ® ® Product Revenue, Net: Shipping and handling costs for product shipments occur prior to the customer obtaining control of the goods and are recorded in cost of sales. If taxes should be collected from the Customer relating to product sales and remitted to governmental authorities, they will be excluded from revenue. The Company expenses incremental costs of obtaining a contract when incurred if the expected amortization period of the asset that the Company would have recognized is one year or less. However, no such costs were incurred during the three months ended March 31, 2024 and 2023. During the three months ended March 31, 2024 and 2023, substantially all of the Company’s product revenues were from sales to customers in the U.S. The following table summarizes the Company’s net product revenue disaggregated by product (in thousands): For the Three Months Ended 2024 2023 FIRDAPSE ® $ 66,842 $ 57,526 FYCOMPA ® 30,425 27,778 AGAMREE ® 1,174 —  Total product revenue, net $ 98,441 $ 85,304 Reserves for Variable Consideration: These estimates take into consideration a range of possible outcomes which are probability-weighted in accordance with the expected value method in Topic 606 for relevant factors such as current contractual and statutory requirements, specific known market events and trends, industry data, and forecasted customer buying and payment patterns. Overall, these reserves reflect the Company’s best estimates of the amount of consideration to which it is entitled based on the terms of the respective underlying contracts. The amount of variable consideration which 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 under the contract will not occur in a future period. The Company’s analyses also contemplates application of the constraint in accordance with the guidance, under which it determined a material reversal of revenue would not occur in a future period for the estimates detailed below as of March 31, 2024 and, therefore, the transaction price was not reduced further during the three months ended March 31, 2024 and 2023. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company will adjust these estimates, which would affect net product revenue and earnings in the period such variances become known. Trade Discounts, Allowances and Wholesaler Fees: Prompt Payment Discounts: Funded Co-pay co-pay co-pay Product Returns: Provider Chargebacks and Discounts: ® ® ® These reserves are established in the same period that the related revenue is recognized, resulting in a reduction of product revenue, net and accounts receivable, net. Chargeback amounts are generally determined at the time of resale to the qualified healthcare provider by the customer or at the time of a resale to a FYCOMPA ® Government Rebates: The Company’s liability for these rebates consists of invoices received for claims from prior quarters that have not been paid or for which an invoice has not yet been received, estimates of claims for the current quarter, and estimated future claims that will be made for product that has been recognized as revenue, but which remains in the distribution channel inventories at the end of each reporting period. Payor Rebates: Bridge and Patient Assistance Programs: ® ® pre-established ® ® ® ® ® ® ® ® The Company provides FYCOMPA ® pre-established ® ® The Company does not recognize any revenue related to these free products and the associated costs are classified in selling, general and administrative expenses in the Company’s consolidated statements of operations and comprehensive income. Revenues from Collaboration and Licensing Arrangements: The Company analyzes license and collaboration arrangements pursuant to FASB ASC Topic 808, Collaborative Arrangement Guidance and Consideration (Topic 808), to assess whether such arrangements, or transactions between arrangement participants, involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities or are more akin to a vendor-customer relationship. In making this evaluation, the Company considers whether the activities of the collaboration are considered to be distinct and deemed to be within the scope of the collaborative arrangement guidance or if they are more reflective of a vendor-customer relationship and, therefore, within the scope of Topic 606. This assessment is performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. For elements of collaboration arrangements that are not accounted for pursuant to guidance in Topic 606, an appropriate recognition method is determined and applied consistently, generally by analogy to the revenue from contracts with customers guidance. The Company evaluates the performance obligations promised in the contract that are based on goods and services that will be transferred to the customer and determines whether those obligations are both (i) capable of being distinct and (ii) distinct in the context of the contract. Goods or services that meet these criteria are considered distinct performance obligations. The Company estimates the transaction price based on the amount expected to be received for transferring the promised goods or services in the contract. The consideration may include fixed consideration or variable consideration. The agreements provide for milestone payments upon achievement of development and regulatory events. The Company accounts for milestone payments as variable consideration in accordance with Topic 606. At the inception of each arrangement that includes variable consideration, the Company evaluates the amount of potential transaction price and the likelihood that the transaction price will be received. The Company utilizes either the most likely amount method or expected value method to estimate the amount expected to be received based on which method best predicts the amount expected to be received. The amount of variable consideration that is included in the transaction price may be constrained and is included in the transaction 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. Arrangements that include rights to additional goods or services that are exercisable at a customer’s discretion are generally considered options. The Company assesses if these options provide a material right to the customer and, if so, these options are considered performance obligations. After contract inception, the transaction price is reassessed at every period end and updated for changes such as resolution of uncertain events. Any change in the overall transaction price is allocated to the performance obligations based on the same methodology used at contract inception. The Company recognizes sales-based royalties or net profit-sharing when the latter of (a) the subsequent sale occurs, or (b) the performance obligation to which the sales-based royalty or net profit-sharing has been allocated has been satisfied. Payments to and from the collaborator are presented in the statement of operations based on the nature of the Company’s business operations, the nature of the arrangement, including the contractual terms, and the nature of the payments. Refer to Note 11 (Collaborative and Licensing Arrangements), for further discussion on the Company’s collaborative and licensing arrangements. q. RESEARCH AND DEVELOPMENT. The Company records upfront and milestone payments made to third parties under licensing and collaboration arrangements that occur before a compound receives regulatory approval as acquired in-process research and development (IPR&D). IPR&D acquired as part of an asset acquisition with no alternative future use is expensed immediately to research and development. Milestone payments made after regulatory approval are capitalized as a developed asset and unless the asset is determined to have an indefinite life, the Company amortizes its definite-lived intangible assets using the straight-line method, which is considered the best estimate of economic benefit, over its estimated useful life. r. ADVERTISING EXPENSE. s. STOCK-BASED COMPENSATION. t. CONCENTRATION OF RISK. The Company sells its products, FIRDAPSE ® ® ® As of March 31, 2024, the Company had three FDA approved products, which makes it difficult to evaluate its current business, predict its future prospects, and forecast financial performance and growth. The Company had invested a significant portion of its efforts and financial resources in the development and commercialization of its lead product, FIRDAPSE ® ® ® ® The Company relies exclusively on third parties to formulate and manufacture its products and any future drug candidates. The commercialization of its products and any other drug candidates, if approved, could be stopped, delayed or made less profitable if those third parties fail to provide sufficient quantities of product or fail to do so at acceptable quality levels or prices. The Company does not intend to establish its own manufacturing facilities. The Company is using the same third-party contractors to manufacture, supply, store and distribute drug supplies for clinical trials and for the commercialization of FIRDAPSE ® ® The following table illustrates the approximate percentage of the Company’s total net product revenue attributed to the Company’s largest customers for the periods presented: For the Three Months Ended 2024 2023 Customer A 69.1 % 67.4 % Customer B* —  32.6 % Customer C 10.5 % —  Customer D 10.1 % —  Total 89.7 % 100.0 % *During 2023, the Company sold FYCOMPA ® ® u. ROYALTIES. ® ® disclosed Royalties incurred in connection with the Company’s license agreement for RUZURGI ® agreement v. INCOME TAXES. The Company recognizes the financial statement benefit of a tax position only after determining that the relevant tax authority would more likely than not sustain the position following an audit. For tax positions meeting the more-likely-than-not w. COMPREHENSIVE INCOME. available-for-sale x. NET INCOME PER COMMON SHARE. Diluted net income per common share is computed by dividing net income by the weighted average number of common shares outstanding, increased by the assumed conversion of other potentially dilutive securities during the period. The following table reconciles basic and diluted weighted average common shares: For the Three Months Ended 2024 2023 Basic weighted average common shares outstanding 116,806,117 105,561,229 Effect of dilutive securities 6,597,509 8,424,900 Diluted weighted average common shares outstanding 123,403,626 113,986,129 Outstanding common stock equivalents totaling approximately 5.2 million and 1.3 million, were excluded from the calculation of diluted net income per common share for the three months ended March 31, 2024 and 2023, respectively, as their effect would be anti-dilutive. y. SEGMENT INFORMATION. z. RECLASSIFICATIONS. aa. RECENTLY ISSUED ACCOUNTING STANDARDS. In November 2023, the FASB issued ASU No. 2023-07, Improvements to Reportable Segment Disclosures 2023-07) 2023-07 In December 2023, the FASB issued ASU No. 2023-09,

Investments

Investments	3 Months Ended
	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Investments	3. Investments. Available-for-sale Estimated Gross Gross Amortized At March 31, 2024: U.S. Treasuries—Cash equivalents $ —  $ —  $ —  $ —  Total $ —  $ —  $ —  $ —  At December 31, 2023: U.S. Treasuries—Cash equivalents $ 94,523 $ 18 $ —  $ 94,505 Total $ 94,523 $ 18 $ —  $ 94,505 There were no realized gains or losses from available-for-sale For the Three Months Ended 2024 2023 Equity securities: Net gains (losses) recognized during the period on equity securities $ (1,144 ) $ —  Unrealized net gains (losses) recognized during the period on equity securities still held at the reporting date $ (1,144 ) $ —  There were no sales of equity securities during the three months ended March 31, 2024 and 2023. Unrealized net gains (losses) recognized during the periods on equity securities are included in other income, net in the consolidated statements of operations.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income	3 Months Ended
	Mar. 31, 2024
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income	4. Accumulated Other Comprehensive Income. The following table summarizes the changes in accumulated other comprehensive income, net of tax from unrealized gains (losses) on available-for-sale There were no reclassifications out of accumulated other comprehensive income during the three months ended March 31, 2024 or 2023. Total Accumulated Balance at December 31, 2023 $ 14 Other comprehensive gain (loss) before reclassifications (14 ) Amount reclassified from accumulated other comprehensive income —  Net current period other comprehensive gain (loss) (14 ) Balance at March 31, 2024 $ —  Total Accumulated Balance at December 31, 2022 $ 24 Other comprehensive gain (loss) before reclassifications (13 ) Amount reclassified from accumulated other comprehensive income —  Net current period other comprehensive gain (loss) (13 ) Balance at March 31, 2023 $ 11

Inventory

Inventory	3 Months Ended
	Mar. 31, 2024
Inventory Disclosure [Abstract]
Inventory	5. Inventory. Inventory consists of the following (in thousands): March 31, 2024 December 31, 2023 Raw materials $ 5,926 $ 1,910 Work-in-process 3,963 4,573 Finished goods 10,064 9,161 Total inventory $ 19,953 $ 15,644

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Prepaid Expenses and Other Current Assets	6. Prepaid Expenses and Other Current Assets. Prepaid expenses and other current assets consist of the following (in thousands): March 31, 2024 December 31, 2023 Prepaid manufacturing costs $ 2,005 $ 2,005 Prepaid tax 307 1,238 Prepaid insurance 952 1,332 Prepaid subscriptions fees 1,937 1,299 Prepaid research fees 1,513 1,500 Prepaid commercialization expenses 2,951 3,038 Due from collaborative and licensing arrangements 143 138 Prepaid conference and travel expenses 844 771 Prepaid co-pay 1,561 863 Other 1,532 351 Total prepaid expenses and other current assets $ 13,745 $ 12,535

Operating Leases

Operating Leases	3 Months Ended
	Mar. 31, 2024
Operating Lease, Lease Income [Abstract]
Operating Leases	7. Operating Leases. The Company has an operating lease agreement for its corporate office. The lease includes an option to extend the lease for up to 5 years and options to terminate the lease within 6 The Company entered into an agreement in May 2020 that amended its lease for its office facilities. Under the amended lease, the Company’s leased space increased from approximately 7,800 square feet of space to approximately 10,700 square feet of space. The amended lease commenced in March 2021 when construction of the asset was completed and space became available for use. The components of lease expense were as follows (in thousands): For the Three Months Ended 2024 2023 Operating lease cost $ 108 $ 108 Supplemental cash flow information related to lease was as follows (in thousands): For the Three Months Ended 2024 2023 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows $ 129 $ 125 Right-of-use Operating lease $ 22 $ 22 Supplemental balance sheet information related to lease was as follows (in thousands): March 31, 2024 December 31, 2023 Operating lease right-of-use $ 2,440 $ 2,508 Other current liabilities $ 377 $ 369 Operating lease liabilities, net of current portion 3,091 3,188 Total operating lease liabilities $ 3,468 $ 3,557 As of March 31, 2024 and December 31, 2023, the weighted average remaining lease term was 7.1 years and 7.3 years, respectively. The weighted average discount rate used to determine the operating lease liabilities was 4.51% as of March 31, 2024 and December 31, 2023. Remaining payments of lease liabilities as of March 31, 2024 were as follows (in thousands): 2024 (remaining nine months) $ 394 2025 537 2026 553 2027 570 2028 587 Thereafter 1,440 Total lease payments 4,081 Less: imputed interest (613 ) Total $ 3,468 Rent expense was approximately $0.1 million for each of the three-month periods ended March 31, 2024 and 2023.

Property and Equipment, Net

Property and Equipment, Net	3 Months Ended
	Mar. 31, 2024
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	8. Property and Equipment, Net. Property and equipment, net consists of the following (in thousands): March 31, 2024 December 31, 2023 Furniture and equipment $ 692 $ 494 Leasehold improvements 991 991 Software 433 433 Less: Accumulated depreciation (808 ) (723 ) Total property and equipment, net $ 1,308 $ 1,195

License and Acquired Intangible

License and Acquired Intangibles, Net	3 Months Ended
	Mar. 31, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
License and Acquired Intangibles, Net	9. License and Acquired Intangibles, Net. The following table presents the Company’s intangible assets at March 31, 2024 (in thousands): Gross Accumulated Net Intangible assets: License and acquired intangibles for RUZURGI ® $ 33,569 $ 3,998 $ 29,571 License and acquired intangibles for FYCOMPA ® 158,143 37,580 120,563 License and acquired intangibles for AGAMREE ® 36,000 1,429 34,571 Total $ 227,712 $ 43,007 $ 184,705 The following table presents the Company’s intangible assets at December 31, 2023 (in thousands): Gross Accumulated Net Intangible assets: License and acquired intangibles for RUZURGI ® $ 33,569 $ 3,418 $ 30,151 License and acquired intangibles for FYCOMPA ® 158,143 29,673 128,470 License and acquired intangibles for AGAMREE ® 36,000 572 35,428 Total $ 227,712 $ 33,663 $ 194,049 The Company amortizes its definite-lived intangible assets using the straight-line method, which is considered the best estimate of economic benefit, over its estimated useful life. The estimated useful life used for this purpose for RUZURGI ® ® ® The Company recorded approximately $0.6 million in amortization expense related to the licensed and acquired intangibles for RUZURGI ® ® ® ® ® ® The following table presents future amortization expense the Company expects for its intangible assets (in thousands): 2024 (remaining nine months) $ 28,034 2025 37,378 2026 37,378 2027 37,378 2028 7,705 Thereafter 36,832 Total $ 184,705 At March 31, 2024 and December 31, 2023, the weighted average amortization period remaining for intangible assets was 6.2 years and 6.5 years, respectively. If all or a portion of the intangible assets are deemed not recoverable, the Company would estimate the fair value of the assets and record an impairment loss. There were no impairment charges recognized on definite-lived intangibles for the three months ended March 31, 2024 or 2023.

Accrued Expenses and Other Liab

Accrued Expenses and Other Liabilities	3 Months Ended
	Mar. 31, 2024
Payables and Accruals [Abstract]
Accrued Expenses and Other Liabilities	10. Accrued Expenses and Other Liabilities. Accrued expenses and other liabilities consist of the following (in thousands): March 31, 2024 December 31, 2023 Accrued preclinical and clinical trial expenses $ 527 $ 1,015 Accrued professional fees 5,856 4,730 Accrued compensation and benefits 4,852 8,883 Accrued license fees 8,934 24,437 Accrued purchases 694 192 Operating lease liability 377 369 Accrued gross-to-net revenue liabilities * 24,885 6,877 Accrued income tax 7,340 729 Due to licensor 12,205 12,540 Accrued interest payable 1,204 1,031 Accrued charitable contributions 1,800 —  Other 631 465 Current accrued expenses and other liabilities 69,305 61,268 Lease liability – non-current 3,091 3,188 Due to licensor – non-current 1,859 2,497 Other – non-current 748 485 Non-current 5,698 6,170 Total accrued expenses and other liabilities $ 75,003 $ 67,438 *During 2023, the Company sold FYCOMPA ® ®

Collaborative and Licensing Arr

Collaborative and Licensing Arrangements	3 Months Ended
	Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaborative and Licensing Arrangements	11. Collaborative Endo, Inc. In December 2018, the Company entered into a collaboration and license agreement (Collaboration) with Endo, Inc. (formerly, Endo International plc) (Endo), for the further development and commercialization of generic Sabril ® ® In October 2023, Endo informed the Company that it has discontinued work on the Collaboration for development and commercialization of vigabatrin and that it wished to terminate the arrangement. As the Company proceeds with the termination process, the Company does not expect the end of the collaboration to have a material impact on the Company’s consolidated financial statements. KYE Pharmaceuticals Inc. In August 2020, the Company entered into a collaboration and license agreement with KYE Pharmaceuticals Inc. (KYE), for the commercialization of FIRDAPSE ® Under the agreement, Catalyst granted KYE an exclusive license to commercialize and market FIRDAPSE ® ® Under the terms of the agreement, the Company will receive an up-front ® mid-double-digit ® This agreement is in form identified as a collaborative agreement and the Company has concluded for accounting purposes that it also represents a contract with a customer. This is because the Company grants to KYE a license and provides supply of FIRDAPSE ® The collaborative agreement included a nonrefundable upfront license fee that was recognized upon transfer of the license based on a determination that the right is provided as the intellectual property exists at the point in time in which the license is granted. Revenue from sales of FIRDAPSE ® Revenues from the arrangement with KYE for the three months ended March 31, 2024 and 2023 were not material. Revenue is included in license and other revenue in the accompanying consolidated statements of operations and comprehensive income. Expenses incurred, net have been included in selling, general and administrative expenses in the accompanying consolidated statements of operations and comprehensive income. DyDo Pharma, Inc. On June 28, 2021, the Company entered into a license agreement with DyDo Pharma, Inc. (DyDo), for the development and commercialization of FIRDAPSE ® Under the agreement, DyDo has joint rights to develop FIRDAPSE ® Under the terms of the agreement, the Company has earned an up-front ® The Company has concluded that this license agreement will be accounted for pursuant to Topic 606. The agreement included a nonrefundable upfront license fee that was recognized upon the effective date of the agreement as the intellectual property exists at the point in time in which the right to the license is granted. The Company determined the granting of the right to the license is distinct from the supply of FIRDAPSE ® The agreement includes milestones that are considered a sales-based royalty in which the license is deemed to be the predominant item to which these milestones relate. Revenue will be recognized when the latter of (a) the subsequent sale occurs, or (b) the performance obligation to which the sales-based royalty has been allocated has been satisfied. Additionally, the agreement includes regulatory milestone payments which represent variable consideration, and due to uncertainty are fully constrained and only recognized when the uncertainty is subsequently resolved. For clinical and commercial supply of the product, the Company will recognize revenue when the Customer obtains control of the Company’s product, which will occur at a point in time which is generally at time of shipment. There was $ million in revenue from the arrangement with DyDo for the three months ended March 31, 2024 and 2023, respectively, which is included in product revenue, net in the accompanying consolidated statements of operations and comprehensive income.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. Commitments and Contingencies. In May 2019, the FDA approved a NDA for RUZURGI ® (3,4-DAP), ® ® On July 30, 2020, the Magistrate Judge considering this lawsuit filed a Report and Recommendation in which the Magistrate Judge recommended to the District Judge handling the case that the District Judge grant the FDA’s and Jacobus’ motions for summary judgment and deny the Company’s motion for summary judgment. On September 29, 2020, the District Judge adopted the Report and Recommendation of the Magistrate Judge, granted the FDA’s and Jacobus’ motions for summary judgment, and dismissed the Company’s case. The Company appealed the District Court’s decision to the U.S. Court of Appeals for the 11 th On September 30, 2021, a three-judge panel of 11 th ® th th th th th ® 7-year ® On July 11, 2022, the Company settled certain of its disputes with Jacobus. In connection with the settlement, the Company licensed the rights to develop and commercialize RUZURGI ® ® ® ® know-how ® ® ® non-competition In connection with the settlement with Jacobus, the Company agreed to pay the following consideration to Jacobus: • $30 million of cash, of which $10 million was paid at the closing of the settlement on July 11, 2022, $10 million was paid on the first anniversary of closing, and the remaining $10 million will be paid on the second anniversary of closing; • An annual royalty on our net sales (as defined in the License and Asset Purchase Agreement between Catalyst and Jacobus) of amifampridine products in the U.S. equal to: (a) for calendar years 2022 through 2025, 1.5% (with a minimum annual royalty of $3.0 million per year), and (b) for calendar years 2026 through the expiration of the last to expire of the Company’s FIRDAPSE ® • If the Company were to receive a priority review voucher for FIRDAPSE ® ® The Company’s New Drug Submission filing for FIRDAPSE ® ® ® ® ® ® ® In January 2023, the Company received Paragraph IV Certification Notice Letters from three generic drug manufacturers advising that they had each submitted an Abbreviated New Drug Application (ANDA) to the FDA seeking authorization from the FDA to manufacture, use or sell a generic version of FIRDAPSE ® ® ® ® On February 20, 2023, the Company received a Paragraph IV Certification Notice Letter from a company that appears to have filed the first ANDA for the oral suspension formulation for FYCOMPA ® ® non-infringement, non-validity, ® ® ® ® 30-month Additionally, from time to time the Company may become involved in legal proceedings arising in the ordinary course of business. Except as set forth above, the Company believes that there is no other litigation pending at this time that could have, individually or in the aggregate, a material adverse effect on its results of operations, financial condition, or cash flows.

Agreements

Agreements	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Agreements	13. Agreements. a. LICENSE AGREEMENT FOR FIRDAPSE ® ® ® ® On May 29, 2019, the Company and BioMarin entered into an amendment to the Company’s license agreement for FIRDAPSE ® ® ® On December 18, 2023, DyDo filed a Japan NDA with the PMDA, which was accepted for filing upon its submission. As a result, the Company’s territory automatically expanded on that date to include most of Asia, as well as Latin America. In January 2020, the Company was advised that BioMarin has transferred substantially all of its rights under the license agreement to SERB S.A., and SERB S.A. is now the Company’s licensor under the license agreement. b. LICENSE AGREEMENT FOR RUZURGI ® ® Pursuant to the terms of the license agreement, the Company paid Jacobus a $10 million up-front ® A minimum royalty payment exists annually for calendar years from the Effective Date through 2025 of $3 million, provided that such minimum annual royalty payment shall be prorated in the first calendar year of the agreement. As these minimum payments are both probable and estimable, they are included in the purchase price of the agreement and any royalties in excess of this amount will be charged to cost of sales as revenue from product sales is recognized. A minimum royalty payment exists annually for calendar years from 2026 through the expiration of the royalty term (which ends when there is no valid claim under the Company’s FIRDAPSE ® ® Assets acquired as part of the license agreement include among other intellectual property rights, Jacobus’ U.S. patents related to RUZURGI ® ® ® ® know-how ® Additionally, the Company also purchased from Jacobus approximately $4.1 million of RUZURGI ® Under business combination guidance, the screen test states that if substantially all of the fair value of the gross assets acquired is concentrated in a single identifiable asset or group of similar identifiable assets, the set is not considered a business and is accounted for as an asset acquisition. The Company has determined that the screen test was not met. However, the Company determined that the acquisition did not meet the definition of a business under ASC 805, Business Combination. The Company believes that the licensing agreement and other assets acquired from Jacobus are similar and considered them all to be intangible assets with the exception of the inventory acquired. As the screen test was not met, further determination was required to determine that the Company had not acquired inputs and processes that have the ability to create outputs, which would meet the requirements of a business, and therefore, determined that this was an asset acquisition. The Company accounted for the Jacobus license agreement as an asset acquisition under ASC 805-50, The total purchase price was allocated to the acquired assets based on their relative fair values, as follows (in thousands): License and acquired intangibles $ 33,569 Acquired research and development inventory expensed from asset acquisition 4,130 Total purchase price $ 37,699 The straight-line method is used to amortize the license and acquired intangibles, as disclosed in Note 9 (License and Acquired Intangibles, Net). c. ACQUISITION OF U.S. RIGHTS FOR FYCOMPA ® . ® Eisai was eligible to receive a contingent payment of $25 million if a certain regulatory milestone was met. As meeting the regulatory milestone was not probable, the Company did not recognize any amount related to the milestone payments in the purchase price. Additionally, after the loss of patent exclusivity for FYCOMPA ® ® Royalties commencing on loss of exclusivity for each calendar year during the royalty term equal to 12% on net sales greater than $10 million and less than $100 million, 17% on net sales of greater than $100 million and less than $125 million and 22% on net sales greater than $125 million prior to the date of generic entry. Royalties equal to 6% on net sales greater than $10 million and less than $100 million, 8.5% on net sales of greater than $100 million and less than $125 million and 11% on net sales greater than $125 million after the date of generic entry. The following table summarizes the aggregate amount paid for the assets acquired by the Company in connection with the acquisition of FYCOMPA ® Base cash payment $ 160,000 Cash paid for pro-rated 1,576 Reimbursement on base purchase price (i) (3,238 ) Transaction costs (ii) 5,870 Total purchase consideration $ 164,208 (i) Recorded in prepaid expenses and other current assets in the accompanying consolidated balance sheet as of the acquisition date and reimbursement was fully applied as of June 30, 2023. (ii) As of March 31, 2024, the full $5.9 million has been paid in cash. The acquisition of FYCOMPA ® 805-50. ® ® ® at-market 805-10-55-5A The total purchase price was allocated to the acquired assets based on their relative fair values, as follows (in thousands): Inventory $ 4,100 Prepaid expenses and other current assets (samples) 130 Prepaid commercialization expenses 1,576 Property and equipment, net 433 License and acquired intangibles for FYCOMPA ® 158,143 Accrued preclinical and clinical trial expenses (174 ) Total purchase consideration $ 164,208 The straight-line method is used to amortize the license and acquired intangibles, as disclosed in Note 9 (License and Acquired Intangibles, Net). d. LICENSE AGREEMENT FOR AGAMREE ® (VAMOROLONE). ® ® ® all-cash Under the license agreement, the Company pays: (i) royalties to the licensor until the later of expiration of product exclusivity or ten years from the first commercial sale of AGAMREE ® ® billion. Furthermore, the Company may pay Santhera sales-based milestones of up to $105 million as well as up to 11% percent royalties for all additional indications and milestones of up to $50 million for the first three additional indications. Simultaneously, the Company made a strategic equity investment into Santhera by acquiring 1,414,688 of Santhera’s post reverse-split ordinary shares (representing approximately 11.26% of Santhera’s outstanding ordinary shares following the transaction), which are traded on the SIX Swiss Exchange, at an investment price of CHF 9.477 per share (corresponding to a mutually agreed volume-weighted average price prior to signing), with the funds invested into Santhera to be used by Santhera for Phase IV studies in DMD and further development of additional indications for AGAMREE ® The following table summarizes the aggregate amount paid for the assets acquired by the Company in connection with the acquisition of AGAMREE ® Initial cash payment $ 75,000 Investment in Santhera 13,465 Transaction costs 6,513 Total purchase consideration $ 94,978 The transaction has been accounted for as an asset acquisition in accordance with ASC 805-50. ® ® 805-10-55-5A non-financial The total purchase price was allocated to the acquired assets based on their relative fair values, as follows (in thousands): License and acquired intangibles for AGAMREE ® $ 81,513 Investment in Santhera (i) 13,465 Total purchase consideration $ 94,978 (i) The fair value of the investment in Santhera was determined based on the closing market price (CHF 8.25) of Santhera shares and the exchange rate (1.1537) of CHF to USD on the date the shares were transferred, July 19, 2023. In accordance with FASB ASC 730-10-25, ® Following the approval of the NDA for AGAMREE ® The strategic equity investment in Santhera is accounted for as an investment in equity securities, and is recognized as a non-current e. AGREEMENTS FOR DRUG MANUFACTURING, DEVELOPMENT, PRECLINICAL AND CLINICAL STUDIES.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2024
Income Tax Disclosure [Abstract]
Income Taxes	14. Income Taxes. The Company’s effective income tax rate was 20.0% and 20.8% for the three months ended March 31, 2024 and 2023, respectively. Differences in the effective tax and the statutory federal income tax rate of 21% are driven by state income taxes and anticipated annual permanent differences offset by equity compensation deductions. The Company had no uncertain tax positions as of March 31, 2024 and December 31, 2023.

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2024
Equity [Abstract]
Stockholders' Equity	15. Stockholders’ Equity. Preferred Stock The Company has 5,000,000 shares of authorized preferred stock, $0.001 par value per share, at March 31, 2024 and December 31, 2023. No shares of preferred stock were outstanding at March 31, 2024 and December 31, 2023. Common Stock The Company has 200,000,000 shares of authorized common stock, par value $0.001 per share. At March 31, 2024 and December 31, 2023, 118,029,526 and 107,121,549 shares, respectively, of common stock were issued and outstanding. Each holder of common stock is entitled to one vote of each share of common stock held of record on all matters on which stockholders generally are entitled to vote. Share Repurchases In March 2021, the Company’s Board of Directors approved a share repurchase program that authorizes the repurchase of up to $40 million of the Company’s common stock, pursuant to a repurchase plan under Rule 10b-18 2020 Shelf Registration Statement On July 23, 2020, the Company filed a shelf registration statement with the SEC to sell up to $200 million of common stock, preferred stock, warrants to purchase common stock, debt securities and units consisting of one or more of such securities (the “2020 Shelf Registration Statement”). The 2020 Shelf Registration Statement (file no. 333-240052) 2023 Shelf Registration Statement On September 8, 2023, the Company filed a shelf registration statement with the SEC to sell up to $500 million of common stock, preferred stock, warrants to purchase common stock, debt securities and units consisting of one or more of such securities (the “2023 Shelf Registration Statement”). The 2023 Shelf Registration Statement (file no. 333-274427)

Stock Compensation

Stock Compensation	3 Months Ended
	Mar. 31, 2024
Share-based Payment Arrangement [Abstract]
Stock Compensation	16. Stock Compensation. For the three months ended March 31, 2024 and 2023, the Company recorded stock-based compensation expense as follows (in thousands): 2024 2023 Research and development $ 509 $ 339 Selling, general and administrative 7,739 2,553 Total stock-based compensation $ 8,248 $ 2,892 Stock Options As of March 31, 2024, there were outstanding stock options to purchase 14,241,187 shares of common stock, of which stock options to purchase 8,869,384 shares of common stock were exercisable as of March 31, 2024. During the three months ended March 31, 2024 and 2023, the Company granted seven-year term options to purchase an aggregate of 793,495 and 340,500 shares, respectively, of the Company’s common stock to employees. The Company recorded stock-based compensation related to stock options totaling $5.4 million and $2.2 million, respectively, during the three months ended March 31, 2024 and 2023. During the three months ended March 31, 2024 and 2023, options to purchase 664,432 shares and 547,957 shares, respectively, of the Company’s common stock were exercised, with proceeds of $1.5 million and $1.3 million respectively, to the Company. As of March 31, 2024, there was approximately $36.4 million of unrecognized compensation expense related to non-vested Restricted Stock Units The Company granted 35,693 restricted stock units and no restricted stock units during the three months ended March 31, 2024 and 2023, respectively. During the three months ended March 31, 2024 and 2023, the Company recorded non-cash As of March 31, 2024, there was approximately $7.8 million of unrecognized compensation expense related to non-vested

Basis of Presentation and Sig_2

Basis of Presentation and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
INTERIM FINANCIAL STATEMENTS	a. INTERIM FINANCIAL STATEMENTS. 10-Q In the opinion of management, the accompanying unaudited interim consolidated financial statements of the Company contain all adjustments (consisting of only normal recurring adjustments) necessary to present fairly the financial position of the Company as of the dates and for the periods presented. Accordingly, these consolidated statements should be read in conjunction with the financial statements and notes thereto for the year ended December 31, 2023 included in the 2023 Annual Report on Form 10-K
PRINCIPLES OF CONSOLIDATION	b. PRINCIPLES OF CONSOLIDATION.
USE OF ESTIMATES	c. USE OF ESTIMATES.
CASH AND CASH EQUIVALENTS	d. CASH AND CASH EQUIVALENTS. The Company primarily invests in high credit-quality instruments in order to obtain higher yields on its cash equivalents. The Company considers all highly liquid instruments, purchased with an original maturity of or less, to be cash equivalents. Cash equivalents consist mainly of money market funds and U.S. Treasuries. The Company has substantially all its cash and cash equivalents deposited in money market accounts with one financial institution. These amounts exceed federally insured limits.
INVESTMENTS	e. INVESTMENTS. There were no U.S. Treasuries held at March 31, 2024 and U.S. Treasuries held at December 31, 2023 were classified as available-for-sale non-current The Company records available-for-sale available-for-sale available-for-sale available-for-sale In July 2023, the Company made a strategic equity investment into Santhera by acquiring 1,414,688 of Santhera’s post reverse-split ordinary shares (representing approximately 11.26% of Santhera’s outstanding ordinary shares following the transaction). The investment is denominated in Swiss Francs. The Company has determined that it does not have significant influence over the operations of Santhera and accordingly the investment in Santhera’s ordinary shares is recorded under ASC 321, Equity Securities, with changes in fair value, inclusive of changes resulting from movements in foreign exchange rates, in other income, net in the consolidated statement of operations and comprehensive income.
ACCOUNTS RECEIVABLE, NET	f. ACCOUNTS RECEIVABLE, NET.
INVENTORY	g. INVENTORY work-in-process first-in, Products that have been approved by the FDA or other regulatory authorities, such as FIRDAPSE ® ® ® ® ® ® The Company evaluates for potential excess inventory by analyzing current and future product demand relative to the remaining product shelf life. The Company builds demand forecasts by considering factors such as, but not limited to, overall market potential, market share, market acceptance, and patient usage.
PREPAID EXPENSES AND OTHER CURRENT ASSETS	h. PREPAID EXPENSES AND OTHER CURRENT ASSETS. co-pay pre-clinical
PROPERTY AND EQUIPMENT, NET	i. PROPERTY AND EQUIPMENT, NET. three five five
BUSINESS COMBINATIONS AND ASSET ACQUISITIONS	j BUSINESS COMBINATIONS AND ASSET ACQUISITIONS 805-50, See Notes 12 (Commitments and Contingencies) and 13 (Agreements) for further discussion on the Company’s exclusive license agreement with Jacobus Pharmaceutical Company, Inc. (Jacobus), for the rights to develop and commercialize RUZURGI ® ASC 805-50. ® ® 805-50.
INTANGIBLE ASSETS, NET	k. INTANGIBLE ASSETS, NET. The Company reviews intangible assets with finite lives for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If indicators of impairment exist, an impairment test is performed to assess the recoverability of the affected assets by determining whether the carrying amount of such assets exceeds the undiscounted expected future cash flows. If the affected assets are deemed not recoverable, the Company would estimate the fair value of the assets and record an impairment loss.
FAIR VALUE OF FINANCIAL INSTRUMENTS	l. FAIR VALUE OF FINANCIAL INSTRUMENTS. financial
FAIR VALUE MEASUREMENTS	m. FAIR VALUE MEASUREMENTS. Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2 inputs are inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs may include quoted prices for similar assets and liabilities in active markets, as well as inputs that are observable for the asset or liability (other than quoted prices), such as interest rates, foreign exchange rates, and yield curves that are observable at commonly quoted intervals. Level 3 inputs are unobservable inputs for the asset or liability, which are typically based on an entity’s own assumptions, as there is little, if any, related market activity. In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment and considers factors specific to the asset or liability. Fair Value Measurements at Reporting Date Using (in thousands) Balances as of Quoted Prices in Significant Other Significant Cash and cash equivalents: Money market funds $ 280,802 $ 280,802 $ —  $ —  Investment in equity securities: Equity securities $ 15,345 $ 15,345 $ —  $ —  Fair Value Measurements at Reporting Date Using (in thousands) Balances as of Quoted Prices in Significant Other Significant Cash and cash equivalents: Money market funds $ 18,256 $ 18,256 $ —  $ —  U.S. Treasuries $ 94,523 $ 94,523 $ —  $ —  Investment in equity securities: Equity securities $ 16,489 $ 16,489 $ —  $ —
OPERATING LEASES	n. OPERATING LEASES. right-of-use non-lease
SHARE REPURCHASES	o. SHARE REPURCHASES. The Company accounts for share repurchases by charging the excess of the repurchase price over the repurchased common stock’s par value entirely to retained earnings. All repurchased shares are retired and become authorized but unissued shares. The Company accrues for the shares purchased under the share repurchase plan based on the trade date. The Company may terminate or modify its share repurchase program at any time.
REVENUE RECOGNITION	p. REVENUE RECOGNITION. Product Revenues: To determine revenue recognition for arrangements that are within the scope of Accounting Standards Codification (ASC) Topic 606 – Revenue from Contracts with Customers (Topic 606), the Company performs the following five steps: (i) identify the contract(s) with a customer, (ii) identify the performance obligations in the contract, (iii) determine the transaction price, (iv) allocate the transaction price to the performance obligations in the contract, and (v) recognize revenue when (or as) the entity satisfies a performance obligation. The Company assesses the goods or services promised within each contract and determines those that are performance obligations by assessing whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. For a complete discussion of accounting for product revenue, see Product Revenue, Net below. The Company also may generate revenues from payments received under collaborative and license agreements. Collaborative and license agreement payments may include nonrefundable fees at the inception of the agreements, contingent payments for specific achievements designated in the agreements, and/or net profit-sharing payments on sales of products resulting from the collaborative and license arrangements. For a complete discussion of accounting for collaborative and licensing arrangements, see Revenues from Collaboration and Licensing Arrangements below. The Company recognizes revenue when its customers obtain title of the promised goods, in an amount that reflects the consideration to which the Company expects to be entitled in exchange for these goods. For FIRDAPSE ® ® ® ® ® ® ® ® During 2023, the Company sold FYCOMPA ® ® Product Revenue, Net: Shipping and handling costs for product shipments occur prior to the customer obtaining control of the goods and are recorded in cost of sales. If taxes should be collected from the Customer relating to product sales and remitted to governmental authorities, they will be excluded from revenue. The Company expenses incremental costs of obtaining a contract when incurred if the expected amortization period of the asset that the Company would have recognized is one year or less. However, no such costs were incurred during the three months ended March 31, 2024 and 2023. During the three months ended March 31, 2024 and 2023, substantially all of the Company’s product revenues were from sales to customers in the U.S. The following table summarizes the Company’s net product revenue disaggregated by product (in thousands): For the Three Months Ended 2024 2023 FIRDAPSE ® $ 66,842 $ 57,526 FYCOMPA ® 30,425 27,778 AGAMREE ® 1,174 —  Total product revenue, net $ 98,441 $ 85,304 Reserves for Variable Consideration: These estimates take into consideration a range of possible outcomes which are probability-weighted in accordance with the expected value method in Topic 606 for relevant factors such as current contractual and statutory requirements, specific known market events and trends, industry data, and forecasted customer buying and payment patterns. Overall, these reserves reflect the Company’s best estimates of the amount of consideration to which it is entitled based on the terms of the respective underlying contracts. The amount of variable consideration which 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 under the contract will not occur in a future period. The Company’s analyses also contemplates application of the constraint in accordance with the guidance, under which it determined a material reversal of revenue would not occur in a future period for the estimates detailed below as of March 31, 2024 and, therefore, the transaction price was not reduced further during the three months ended March 31, 2024 and 2023. Actual amounts of consideration ultimately received may differ from the Company’s estimates. If actual results in the future vary from the Company’s estimates, the Company will adjust these estimates, which would affect net product revenue and earnings in the period such variances become known. Trade Discounts, Allowances and Wholesaler Fees: Prompt Payment Discounts: Funded Co-pay co-pay co-pay Product Returns: Provider Chargebacks and Discounts: ® ® ® These reserves are established in the same period that the related revenue is recognized, resulting in a reduction of product revenue, net and accounts receivable, net. Chargeback amounts are generally determined at the time of resale to the qualified healthcare provider by the customer or at the time of a resale to a FYCOMPA ® Government Rebates: The Company’s liability for these rebates consists of invoices received for claims from prior quarters that have not been paid or for which an invoice has not yet been received, estimates of claims for the current quarter, and estimated future claims that will be made for product that has been recognized as revenue, but which remains in the distribution channel inventories at the end of each reporting period. Payor Rebates: Bridge and Patient Assistance Programs: ® ® pre-established ® ® ® ® ® ® ® ® The Company provides FYCOMPA ® pre-established ® ® The Company does not recognize any revenue related to these free products and the associated costs are classified in selling, general and administrative expenses in the Company’s consolidated statements of operations and comprehensive income. Revenues from Collaboration and Licensing Arrangements: The Company analyzes license and collaboration arrangements pursuant to FASB ASC Topic 808, Collaborative Arrangement Guidance and Consideration (Topic 808), to assess whether such arrangements, or transactions between arrangement participants, involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities or are more akin to a vendor-customer relationship. In making this evaluation, the Company considers whether the activities of the collaboration are considered to be distinct and deemed to be within the scope of the collaborative arrangement guidance or if they are more reflective of a vendor-customer relationship and, therefore, within the scope of Topic 606. This assessment is performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. For elements of collaboration arrangements that are not accounted for pursuant to guidance in Topic 606, an appropriate recognition method is determined and applied consistently, generally by analogy to the revenue from contracts with customers guidance. The Company evaluates the performance obligations promised in the contract that are based on goods and services that will be transferred to the customer and determines whether those obligations are both (i) capable of being distinct and (ii) distinct in the context of the contract. Goods or services that meet these criteria are considered distinct performance obligations. The Company estimates the transaction price based on the amount expected to be received for transferring the promised goods or services in the contract. The consideration may include fixed consideration or variable consideration. The agreements provide for milestone payments upon achievement of development and regulatory events. The Company accounts for milestone payments as variable consideration in accordance with Topic 606. At the inception of each arrangement that includes variable consideration, the Company evaluates the amount of potential transaction price and the likelihood that the transaction price will be received. The Company utilizes either the most likely amount method or expected value method to estimate the amount expected to be received based on which method best predicts the amount expected to be received. The amount of variable consideration that is included in the transaction price may be constrained and is included in the transaction 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. Arrangements that include rights to additional goods or services that are exercisable at a customer’s discretion are generally considered options. The Company assesses if these options provide a material right to the customer and, if so, these options are considered performance obligations. After contract inception, the transaction price is reassessed at every period end and updated for changes such as resolution of uncertain events. Any change in the overall transaction price is allocated to the performance obligations based on the same methodology used at contract inception. The Company recognizes sales-based royalties or net profit-sharing when the latter of (a) the subsequent sale occurs, or (b) the performance obligation to which the sales-based royalty or net profit-sharing has been allocated has been satisfied. Payments to and from the collaborator are presented in the statement of operations based on the nature of the Company’s business operations, the nature of the arrangement, including the contractual terms, and the nature of the payments. Refer to Note 11 (Collaborative and Licensing Arrangements), for further discussion on the Company’s collaborative and licensing arrangements.
RESEARCH AND DEVELOPMENT	q. RESEARCH AND DEVELOPMENT. The Company records upfront and milestone payments made to third parties under licensing and collaboration arrangements that occur before a compound receives regulatory approval as acquired in-process research and development (IPR&D). IPR&D acquired as part of an asset acquisition with no alternative future use is expensed immediately to research and development. Milestone payments made after regulatory approval are capitalized as a developed asset and unless the asset is determined to have an indefinite life, the Company amortizes its definite-lived intangible assets using the straight-line method, which is considered the best estimate of economic benefit, over its estimated useful life.
ADVERTISING EXPENSE	r. ADVERTISING EXPENSE.
STOCK-BASED COMPENSATION	s. STOCK-BASED COMPENSATION.
CONCENTRATION OF RISK	t. CONCENTRATION OF RISK. The Company sells its products, FIRDAPSE ® ® ® As of March 31, 2024, the Company had three FDA approved products, which makes it difficult to evaluate its current business, predict its future prospects, and forecast financial performance and growth. The Company had invested a significant portion of its efforts and financial resources in the development and commercialization of its lead product, FIRDAPSE ® ® ® ® The Company relies exclusively on third parties to formulate and manufacture its products and any future drug candidates. The commercialization of its products and any other drug candidates, if approved, could be stopped, delayed or made less profitable if those third parties fail to provide sufficient quantities of product or fail to do so at acceptable quality levels or prices. The Company does not intend to establish its own manufacturing facilities. The Company is using the same third-party contractors to manufacture, supply, store and distribute drug supplies for clinical trials and for the commercialization of FIRDAPSE ® ® The following table illustrates the approximate percentage of the Company’s total net product revenue attributed to the Company’s largest customers for the periods presented: For the Three Months Ended 2024 2023 Customer A 69.1 % 67.4 % Customer B* —  32.6 % Customer C 10.5 % —  Customer D 10.1 % —  Total 89.7 % 100.0 % *During 2023, the Company sold FYCOMPA ® ®
ROYALTIES	u. ROYALTIES. ® ® disclosed Royalties incurred in connection with the Company’s license agreement for RUZURGI ® agreement
INCOME TAXES	v. INCOME TAXES. The Company recognizes the financial statement benefit of a tax position only after determining that the relevant tax authority would more likely than not sustain the position following an audit. For tax positions meeting the more-likely-than-not
COMPREHENSIVE INCOME	w. COMPREHENSIVE INCOME. available-for-sale
NET INCOME PER COMMON SHARE	x. NET INCOME PER COMMON SHARE. Diluted net income per common share is computed by dividing net income by the weighted average number of common shares outstanding, increased by the assumed conversion of other potentially dilutive securities during the period. The following table reconciles basic and diluted weighted average common shares: For the Three Months Ended 2024 2023 Basic weighted average common shares outstanding 116,806,117 105,561,229 Effect of dilutive securities 6,597,509 8,424,900 Diluted weighted average common shares outstanding 123,403,626 113,986,129 Outstanding common stock equivalents totaling approximately 5.2 million and 1.3 million, were excluded from the calculation of diluted net income per common share for the three months ended March 31, 2024 and 2023, respectively, as their effect would be anti-dilutive.
SEGMENT INFORMATION	y. SEGMENT INFORMATION.
RECLASSIFICATIONS	z. RECLASSIFICATIONS.
RECENTLY ISSUED ACCOUNTING STANDARDS	aa. RECENTLY ISSUED ACCOUNTING STANDARDS. In November 2023, the FASB issued ASU No. 2023-07, Improvements to Reportable Segment Disclosures 2023-07) 2023-07 In December 2023, the FASB issued ASU No. 2023-09,

Basis of Presentation and Sig_3

Basis of Presentation and Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2024
Accounting Policies [Abstract]
Fair Value Measurement Specific to Assets or Liability	Fair Value Measurements at Reporting Date Using (in thousands) Balances as of Quoted Prices in Significant Other Significant Cash and cash equivalents: Money market funds $ 280,802 $ 280,802 $ —  $ —  Investment in equity securities: Equity securities $ 15,345 $ 15,345 $ —  $ —  Fair Value Measurements at Reporting Date Using (in thousands) Balances as of Quoted Prices in Significant Other Significant Cash and cash equivalents: Money market funds $ 18,256 $ 18,256 $ —  $ —  U.S. Treasuries $ 94,523 $ 94,523 $ —  $ —  Investment in equity securities: Equity securities $ 16,489 $ 16,489 $ —  $ —
Summary of Disaggregated Product Revenue	The following table summarizes the Company’s net product revenue disaggregated by product (in thousands): For the Three Months Ended 2024 2023 FIRDAPSE ® $ 66,842 $ 57,526 FYCOMPA ® 30,425 27,778 AGAMREE ® 1,174 —  Total product revenue, net $ 98,441 $ 85,304
Summary of Percentage of the Company's Total Net Product Revenue	The following table illustrates the approximate percentage of the Company’s total net product revenue attributed to the Company’s largest customers for the periods presented: For the Three Months Ended 2024 2023 Customer A 69.1 % 67.4 % Customer B* —  32.6 % Customer C 10.5 % —  Customer D 10.1 % —  Total 89.7 % 100.0 % *During 2023, the Company sold FYCOMPA ® ®
Basic and Dilutive Weighted Average Common Shares	The following table reconciles basic and diluted weighted average common shares: For the Three Months Ended 2024 2023 Basic weighted average common shares outstanding 116,806,117 105,561,229 Effect of dilutive securities 6,597,509 8,424,900 Diluted weighted average common shares outstanding 123,403,626 113,986,129

Investments (Tables)

Investments (Tables)	3 Months Ended
	Mar. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Summary of Available-for-Sale Investments by Security type	Available-for-sale Estimated Gross Gross Amortized At March 31, 2024: U.S. Treasuries—Cash equivalents $ —  $ —  $ —  $ —  Total $ —  $ —  $ —  $ —  At December 31, 2023: U.S. Treasuries—Cash equivalents $ 94,523 $ 18 $ —  $ 94,505 Total $ 94,523 $ 18 $ —  $ 94,505
Summary Of Net Gains And Losses On Equity Securities	For the Three Months Ended 2024 2023 Equity securities: Net gains (losses) recognized during the period on equity securities $ (1,144 ) $ —  Unrealized net gains (losses) recognized during the period on equity securities still held at the reporting date $ (1,144 ) $ —

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2024
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Summary of Reclassifications out of Accumulated Other Comprehensive Income	The following table summarizes the changes in accumulated other comprehensive income, net of tax from unrealized gains (losses) on available-for-sale There were no reclassifications out of accumulated other comprehensive income during the three months ended March 31, 2024 or 2023. Total Accumulated Balance at December 31, 2023 $ 14 Other comprehensive gain (loss) before reclassifications (14 ) Amount reclassified from accumulated other comprehensive income —  Net current period other comprehensive gain (loss) (14 ) Balance at March 31, 2024 $ —  Total Accumulated Balance at December 31, 2022 $ 24 Other comprehensive gain (loss) before reclassifications (13 ) Amount reclassified from accumulated other comprehensive income —  Net current period other comprehensive gain (loss) (13 ) Balance at March 31, 2023 $ 11

Inventory (Tables)

Inventory (Tables)	3 Months Ended
	Mar. 31, 2024
Inventory Disclosure [Abstract]
Summary of current inventory	Inventory consists of the following (in thousands): March 31, 2024 December 31, 2023 Raw materials $ 5,926 $ 1,910 Work-in-process 3,963 4,573 Finished goods 10,064 9,161 Total inventory $ 19,953 $ 15,644

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	3 Months Ended
	Mar. 31, 2024
Text Block [Abstract]
Prepaid expenses and other current assets	Prepaid expenses and other current assets consist of the following (in thousands): March 31, 2024 December 31, 2023 Prepaid manufacturing costs $ 2,005 $ 2,005 Prepaid tax 307 1,238 Prepaid insurance 952 1,332 Prepaid subscriptions fees 1,937 1,299 Prepaid research fees 1,513 1,500 Prepaid commercialization expenses 2,951 3,038 Due from collaborative and licensing arrangements 143 138 Prepaid conference and travel expenses 844 771 Prepaid co-pay 1,561 863 Other 1,532 351 Total prepaid expenses and other current assets $ 13,745 $ 12,535

Operating Leases (Tables)

Operating Leases (Tables)	3 Months Ended
	Mar. 31, 2024
Disclosure of Operating Leases [Abstract]
Lease, Cost	The components of lease expense were as follows (in thousands): For the Three Months Ended 2024 2023 Operating lease cost $ 108 $ 108
Schedule of Supplemental Cash Flow Information Related To Lease	Supplemental cash flow information related to lease was as follows (in thousands): For the Three Months Ended 2024 2023 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows $ 129 $ 125 Right-of-use Operating lease $ 22 $ 22
Schedule of Supplemental Balance Sheet related To Lease	Supplemental balance sheet information related to lease was as follows (in thousands): March 31, 2024 December 31, 2023 Operating lease right-of-use $ 2,440 $ 2,508 Other current liabilities $ 377 $ 369 Operating lease liabilities, net of current portion 3,091 3,188 Total operating lease liabilities $ 3,468 $ 3,557
Lessee, Operating Lease, Liability, Maturity	Remaining payments of lease liabilities as of March 31, 2024 were as follows (in thousands): 2024 (remaining nine months) $ 394 2025 537 2026 553 2027 570 2028 587 Thereafter 1,440 Total lease payments 4,081 Less: imputed interest (613 ) Total $ 3,468 Rent expense was approximately $0.1 million for each of the three-month periods ended March 31, 2024 and 2023.

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	3 Months Ended
	Mar. 31, 2024
Property, Plant and Equipment [Abstract]
Property and Equipment, net	Property and equipment, net consists of the following (in thousands): March 31, 2024 December 31, 2023 Furniture and equipment $ 692 $ 494 Leasehold improvements 991 991 Software 433 433 Less: Accumulated depreciation (808 ) (723 ) Total property and equipment, net $ 1,308 $ 1,195

License and Acquired Intangib_2

License and Acquired Intangibles, Net (Tables)	3 Months Ended
	Mar. 31, 2024
Finite-Lived Intangible Assets, Net [Abstract]
Schedule of Finite-Lived Intangible Assets	The following table presents the Company’s intangible assets at March 31, 2024 (in thousands): Gross Accumulated Net Intangible assets: License and acquired intangibles for RUZURGI ® $ 33,569 $ 3,998 $ 29,571 License and acquired intangibles for FYCOMPA ® 158,143 37,580 120,563 License and acquired intangibles for AGAMREE ® 36,000 1,429 34,571 Total $ 227,712 $ 43,007 $ 184,705 The following table presents the Company’s intangible assets at December 31, 2023 (in thousands): Gross Accumulated Net Intangible assets: License and acquired intangibles for RUZURGI ® $ 33,569 $ 3,418 $ 30,151 License and acquired intangibles for FYCOMPA ® 158,143 29,673 128,470 License and acquired intangibles for AGAMREE ® 36,000 572 35,428 Total $ 227,712 $ 33,663 $ 194,049
Schedule of Finite-Lived, Future Amortization Expense	The following table presents future amortization expense the Company expects for its intangible assets (in thousands): 2024 (remaining nine months) $ 28,034 2025 37,378 2026 37,378 2027 37,378 2028 7,705 Thereafter 36,832 Total $ 184,705

Accrued Expenses and Other Li_2

Accrued Expenses and Other Liabilities (Tables)	3 Months Ended
	Mar. 31, 2024
Payables and Accruals [Abstract]
Schedule of Accrued Expenses and Other Liabilities	Accrued expenses and other liabilities consist of the following (in thousands): March 31, 2024 December 31, 2023 Accrued preclinical and clinical trial expenses $ 527 $ 1,015 Accrued professional fees 5,856 4,730 Accrued compensation and benefits 4,852 8,883 Accrued license fees 8,934 24,437 Accrued purchases 694 192 Operating lease liability 377 369 Accrued gross-to-net revenue liabilities * 24,885 6,877 Accrued income tax 7,340 729 Due to licensor 12,205 12,540 Accrued interest payable 1,204 1,031 Accrued charitable contributions 1,800 —  Other 631 465 Current accrued expenses and other liabilities 69,305 61,268 Lease liability – non-current 3,091 3,188 Due to licensor – non-current 1,859 2,497 Other – non-current 748 485 Non-current 5,698 6,170 Total accrued expenses and other liabilities $ 75,003 $ 67,438 *During 2023, the Company sold FYCOMPA ® ®

Agreements (Tables)

Agreements (Tables)	3 Months Ended
	Mar. 31, 2024
Asset Acquisition [Line Items]
Schedule Of Total Purchase Price Was Allocated To The Acquired Assets Based On Their Relative Fair Values	License and acquired intangibles $ 33,569 Acquired research and development inventory expensed from asset acquisition 4,130 Total purchase price $ 37,699
Summary of Aggregate Amount Paid for the Assets Acquired	The following table summarizes the aggregate amount paid for the assets acquired by the Company in connection with the acquisition of FYCOMPA ® Base cash payment $ 160,000 Cash paid for pro-rated 1,576 Reimbursement on base purchase price (i) (3,238 ) Transaction costs (ii) 5,870 Total purchase consideration $ 164,208 (i) Recorded in prepaid expenses and other current assets in the accompanying consolidated balance sheet as of the acquisition date and reimbursement was fully applied as of June 30, 2023. (ii) As of March 31, 2024, the full $5.9 million has been paid in cash.
Summary of Total Purchase Price Allocated to Acquired Assets	The total purchase price was allocated to the acquired assets based on their relative fair values, as follows (in thousands): Inventory $ 4,100 Prepaid expenses and other current assets (samples) 130 Prepaid commercialization expenses 1,576 Property and equipment, net 433 License and acquired intangibles for FYCOMPA ® 158,143 Accrued preclinical and clinical trial expenses (174 ) Total purchase consideration $ 164,208
Vamorolone [Member]
Asset Acquisition [Line Items]
Summary of Aggregate Amount Paid for the Assets Acquired	The following table summarizes the aggregate amount paid for the assets acquired by the Company in connection with the acquisition of AGAMREE ® Initial cash payment $ 75,000 Investment in Santhera 13,465 Transaction costs 6,513 Total purchase consideration $ 94,978
Summary of Total Purchase Price Allocated to Acquired Assets	The total purchase price was allocated to the acquired assets based on their relative fair values, as follows (in thousands): License and acquired intangibles for AGAMREE ® $ 81,513 Investment in Santhera (i) 13,465 Total purchase consideration $ 94,978 (i) The fair value of the investment in Santhera was determined based on the closing market price (CHF 8.25) of Santhera shares and the exchange rate (1.1537) of CHF to USD on the date the shares were transferred, July 19, 2023.

Stock Compensation (Tables)

Stock Compensation (Tables)	3 Months Ended
	Mar. 31, 2024
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation Expense	For the three months ended March 31, 2024 and 2023, the Company recorded stock-based compensation expense as follows (in thousands): 2024 2023 Research and development $ 509 $ 339 Selling, general and administrative 7,739 2,553 Total stock-based compensation $ 8,248 $ 2,892

Organization and Description _2

Organization and Description of Business - Additional Information (Detail) - USD ($) $ in Thousands, shares in Millions		3 Months Ended
	Jan. 09, 2024	Mar. 31, 2024	Mar. 31, 2023
Proceeds from issuance of common stock		$ 141,000	$ 0
Public Offering [Member]
Stock issued during the period shares new issues	10
Proceeds from issuance of common stock	$ 140,700

Basis of Presentation and Sig_4

Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) $ in Thousands				1 Months Ended	3 Months Ended
	Jul. 11, 2025 USD ($)	Jul. 11, 2024 USD ($)	Jul. 11, 2023 USD ($)	Jul. 31, 2023 shares	Mar. 31, 2024 USD ($) Segment shares	Mar. 31, 2023 USD ($) shares	Dec. 31, 2023 USD ($)	Mar. 31, 2021 USD ($)
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Maximum maturity period of cash and cash equivalent					three months
Maximum Amortization Period Of Compensation Cost On Straight Line Basis					3 years
Potential equivalent common stock excluded | shares					5,200,000	1,300,000
Number of operating segments | Segment					1
Asset acquisition equity interests issued or issuable number of shares issued | shares				1,414,688
Asset acquisition percentage of outstanding ordinary shares				11.26%
Debt securities, available-for-sale, current					$ 0		$ 0
Share Purchase Program [Member] | Common Stock [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Share repurchase program, authorised								$ 40,000
License Agreement For RUZURGI [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Minimum royalty	$ 3,000	$ 3,000	$ 3,000
Selling, General and Administrative Expenses [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Advertising Expense					$ 3,900	$ 1,700
Minimum [Member] | Furniture and Equipment [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Useful life of assets					5 years
Minimum [Member] | Computer Equipment [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Useful life of assets					3 years
Minimum [Member] | Leasehold Improvements [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Useful life of assets					5 years
Maximum [Member] | Furniture and Equipment [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Useful life of assets					7 years
Maximum [Member] | Computer Equipment [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Useful life of assets					5 years
Maximum [Member] | Leasehold Improvements [Member]
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items]
Useful life of assets					10 years

Basis of Presentation and Sig_5

Basis of Presentation and Significant Accounting Policies - Fair Value Measurement Specific to Assets or Liability (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	$ 15,345	$ 16,489
U.S. Treasuries [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		94,523
Money market funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	280,802	18,256
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity securities	15,345	16,489
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | U.S. Treasuries [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		94,523
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Money market funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 280,802	$ 18,256

Basis of Presentation and Sig_6

Basis of Presentation and Significant Accounting Policies - Summary of Disaggregated Product Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 98,509	$ 85,366
FIRDAPSE [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	66,842	57,526
FYCOMPA [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	30,425	27,778
AGAMREE [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,174
Product revenue, net [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 98,441	$ 85,304

Basis of Presentation and Sig_7

Basis of Presentation and Significant Accounting Policies - Summary of Percentage of the Company's Total Net Product Revenue (Detail) - Revenue Benchmark [Member] - Customer Concentration Risk [Member]		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Customer A [Member]
Concentration Risk [Line Items]
Concentration risk, percentage		69.10%	67.40%
Customer B [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	[1]	0%	32.60%
Customer C [Member]
Concentration Risk [Line Items]
Concentration risk, percentage		10.50%	0%
Customer D [Member]
Concentration Risk [Line Items]
Concentration risk, percentage		10.10%	0%
Customer [Member]
Concentration Risk [Line Items]
Concentration risk, percentage		89.70%	100%
[1]During 2023, the Company sold FYCOMPA® through a Transition Service Agreement with Eisai. Effective January 1, 2024, FYCOMPA® is being sold and distributed through a 3PL organization.

Basis of Presentation and Sig_8

Basis of Presentation and Significant Accounting Policies - Schedule Of Reconcile Basic And Dilutive Weighted Average Common Shares (Detail) - shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Basic weighted average common shares outstanding	116,806,117	105,561,229
Effect of dilutive securities	6,597,509	8,424,900
Diluted weighted average common shares outstanding	123,403,626	113,986,129

Investments - Additional Inform

Investments - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Realized gains losses from available for sale securities	$ 0	$ 0

Investments - Summary of Availa

Investments - Summary of Available-for-Sale Investments by Security type (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Net Investment Income [Line Items]
Estimated Fair Value	$ 0	$ 94,523
Gross Unrealized Gains	0	18
Gross Unrealized Losses	0	0
Amortized cost	0	94,505
U.S. Treasuries—Cash equivalents [Member]
Net Investment Income [Line Items]
Estimated Fair Value	0	94,523
Gross Unrealized Gains	0	18
Gross Unrealized Losses	0	0
Amortized cost	$ 0	$ 94,505

Investments - Summary Of Net Ga

Investments - Summary Of Net Gains And Losses On Equity Securities (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Investments, Debt and Equity Securities [Abstract]
Net gains (losses) recognized during the period on equity securities	$ (1,144)	$ 0
Unrealized net gains (losses) recognized during the period on equity securities still held at the reporting date	$ (1,144)	$ 0

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income - Summary of Reclassifications out of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Accumulated Other Comprehensive Incom [Line Items]
Beginning balance	$ 14	$ 24
Other comprehensive gain (loss) before reclassifications	(14)	(13)
Amount reclassified from accumulated other comprehensive income	0	0
Net current period other comprehensive gain (loss)	(14)	(13)
Ending balance	$ 0	$ 11

Inventory - Summary of current

Inventory - Summary of current inventory (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Inventory Disclosure [Abstract]
Raw materials	$ 5,926	$ 1,910
Work-in-process	3,963	4,573
Finished goods	10,064	9,161
Total inventory	$ 19,953	$ 15,644

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets - Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid manufacturing costs	$ 2,005	$ 2,005
Prepaid tax	307	1,238
Prepaid insurance	952	1,332
Prepaid subscriptions fees	1,937	1,299
Prepaid research fees	1,513	1,500
Prepaid commercialization expenses	2,951	3,038
Due from collaborative and licensing arrangements	143	138
Prepaid conference and travel expenses	844	771
Prepaid co-pay assistance program	1,561	863
Other	1,532	351
Total prepaid expenses and other current assets	$ 13,745	$ 12,535

Operating Leases - Operating Le

Operating Leases - Operating Leases (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Disclosure of Operating Leases [Abstract]
Operating lease cost	$ 108	$ 108

Operating Leases - Schedule of

Operating Leases - Schedule of Supplemental Cash Flow Information Related To Lease (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows	$ 129	$ 125
Right-of-use assets obtained in exchange for lease obligations:
Operating leases	$ 22	$ 22

Operating Leases - Schedule o_2

Operating Leases - Schedule of Supplemental Balance Sheet related To Lease (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Disclosure of Operating Leases [Line Items]
Operating lease right-of-use assets	$ 2,440	$ 2,508
Other current liabilities	$ 377	$ 369
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Liabilities, Current	Liabilities, Current
Operating lease liabilities, net of current portion	$ 3,091	$ 3,188
Total operating lease liabilities	$ 3,468	$ 3,557

Operating Leases - Lessee, Oper

Operating Leases - Lessee, Operating Lease, Liability, Maturity (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Disclosure of Operating Leases [Line Items]
2024 (remaining nine months)	$ 394
2025	537
2026	553
2027	570
2028	587
Thereafter	1,440
Total lease payments	4,081
Less: imputed interest	(613)
Total	$ 3,468	$ 3,557

Operating Leases - Additional

Operating Leases - Additional Information (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) ft²	Mar. 31, 2023 USD ($)	Dec. 31, 2023
Disclosure of Operating Leases [Line Items]
Finance Lease Obligations | $	$ 0
Lessee, Operating Lease, Option to Extend	5 years
Before agreement of company leased spaces | ft²	7,800
After agreement of company leased spaces | ft²	10,700
Weighted average remaining lease term	7 years 1 month 6 days		7 years 3 months 18 days
Weighted average discount rate	4.51%		4.51%
Rent expense | $	$ 108	$ 108
Maximum [Member]
Disclosure of Operating Leases [Line Items]
Lessee, Operating Lease, Option to Terminate	7.6 years
Minimum [Member]
Disclosure of Operating Leases [Line Items]
Lessee, Operating Lease, Option to Terminate	6 years

Property and Equipment, Net - P

Property and Equipment, Net - Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Less: Accumulated depreciation	$ (808)	$ (723)
Total property and equipment, net	1,308	1,195
Furniture and equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	692	494
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	991	991
Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 433	$ 433

License and Acquired Intangib_3

License and Acquired Intangibles, Net - Schedule of Finite Lived Intangible Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 227,712	$ 227,712
Accumulated Amortization	43,007	33,663
Net Carrying Value	184,705	194,049
License and Acquired Intangibles for RUZURGI [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	33,569	33,569
Accumulated Amortization	3,998	3,418
Net Carrying Value	29,571	30,151
License and Acquired Intangibles for FYCOMPA [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	158,143	158,143
Accumulated Amortization	37,580	29,673
Net Carrying Value	120,563	128,470
Licensed And Acquired Intangibles For AGAMREE [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	36,000	36,000
Accumulated Amortization	1,429	572
Net Carrying Value	$ 34,571	$ 35,428

License and Acquired Intangib_4

License and Acquired Intangibles, Net - Schedule of Finite-Lived, Future Amortization Expense (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
2024 (remaining nine months)	$ 28,034
2025	37,378
2026	37,378
2027	37,378
2028	7,705
Thereafter	36,832
Total	$ 184,705	$ 194,049

License and Acquired Intangib_5

License and Acquired Intangibles, Net - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 9,344	$ 6,531
Impairment charges recognized on definite-lived intangibles	$ 0	0
Finite-Lived Intangible Assets, Remaining Amortization Period	6 years 2 months 12 days		6 years 6 months
License and Acquired Intangibles for RUZURGI [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	14 years 6 months
Amortization of intangible assets	$ 600	600
License and Acquired Intangibles for FYCOMPA [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	5 years
Amortization of intangible assets	$ 7,900	6,000
Licensed And Acquired Intangibles For AGAMREE [Member]
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible asset, useful life	10 years 6 months
Amortization of intangible assets	$ 900	$ 0

Accrued Expenses and Other Li_3

Accrued Expenses and Other Liabilities - Schedule of Accrued Expenses and Other Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Payables and Accruals [Abstract]
Accrued preclinical and clinical trial expenses	$ 527	$ 1,015
Accrued professional fees	5,856	4,730
Accrued compensation and benefits	4,852	8,883
Accrued license fees	8,934	24,437
Accrued purchases	694	192
Operating lease liability	377	369
Accrued gross-to-net revenue liabilities	24,885	6,877
Accrued income tax	7,340	729
Due to licensor	12,205	12,540
Accrued interest payable	1,204	1,031
Accrued charitable contributions	1,800	0
Other	631	465
Current accrued expenses and other liabilities	69,305	61,268
Lease liability – non-current	3,091	3,188
Due to licensor – non-current	1,859	2,497
Other – non-current	748	485
Non-current accrued expenses and other liabilities	5,698	6,170
Total accrued expenses and other liabilities	$ 75,003	$ 67,438

Collaborative and Licensing A_2

Collaborative and Licensing Arrangements - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
KYE Pharmaceuticals [Member] | Selling, General and Administrative Expenses [Member]
Collaborative Arrangements [Line Items]
Expenses incurred in connection with collaboration agreement	$ 0	$ 0
Collaborative Arrangement [Member] | Dydo Pharma Inc [Member]
Collaborative Arrangements [Line Items]
Revenues	$ 0	$ 200,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions		1 Months Ended
	Jul. 11, 2022	Jan. 31, 2023	Jul. 11, 2024	Jul. 11, 2023
Commitments [Line Items]
Number of trading days from receipt of the notice letter		45 days
License and asset purchase agreement payment made in first year	$ 10			$ 10
Subsequent Event [Member]
Commitments [Line Items]
License and asset purchase agreement payment made in first year			$ 10
License and Asset Purchase Agreement [Member]
Commitments [Line Items]
Purchase price of an asset acquisition	$ 30
Percentage of the consideration paid by a third party to acquire that voucher	50%
License and Asset Purchase Agreement [Member] | Calendar Years 2022 Through 2025 [Member]
Commitments [Line Items]
Percentage of annual royalty on the Company's net sales	1.50%
Minimum royalty amount	$ 3
License and Asset Purchase Agreement [Member] | Calendar Year 2026 [Member]
Commitments [Line Items]
Percentage of annual royalty on the Company's net sales	2.50%
Minimum royalty amount	$ 5

Agreements - Additional Informa

Agreements - Additional Information (Detail) $ in Thousands						1 Months Ended		3 Months Ended
	Jul. 11, 2025 USD ($)	Jul. 11, 2024 USD ($)	Jul. 19, 2023 SFr / shares	Jul. 11, 2023 USD ($)	Jul. 11, 2022 USD ($)	Jul. 31, 2023 USD ($) shares	Jul. 31, 2023 SFr / shares	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Mar. 31, 2023 USD ($)	Oct. 26, 2023 USD ($)
License Agreement [Line Items]
Percentage of royalty on net sales								3.50%
Research and development expenses								$ 2,581		$ 3,562
Asset acquisition equity interests issued or issuable number of shares issued | shares						1,414,688
Asset Acquisition Percentage Of Outstanding Ordinary Shares						11.26%
U.S. Rights for FYCOMPA [Member]
License Agreement [Line Items]
Date on which strategic collaboration is entered into								Jan. 24, 2023
Payments to acquire productive assets								$ 164,200
Contingent consideration liability								$ 25,000
U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								6%
U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								12%
U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred And Twenty Five Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								11%
Net sales royalty threshold								$ 125,000
U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred And Twenty Five Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								22%
Net sales royalty threshold								$ 125,000
U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								8.50%
U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								17%
Vamorolone [Member]
License Agreement [Line Items]
Payments to acquire productive assets						$ 75,000
Asset acquisition equity interests issued or issuable number of shares issued | shares						1,414,688
Asset Acquisition Percentage Of Outstanding Ordinary Shares						11.26%
Asset Acquisition Investment Share Price | SFr / shares							SFr 9.477
Closing Market Price | SFr / shares			SFr 8.25
Foreign Currency Exchange Rate, Translation			1.1537
Collaborative arrangement, milestone payment obligation											$ 36,000
Payment on milestone payment									$ 36,000
Capitalized amortized Cost									$ 36,000
Finite-lived intangible asset, useful life								10 years 6 months
AGAMREE [Member] | Royalty Less Than Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								5%
AGAMREE [Member] | Royalty More Than Hundred Million And Less Than Two Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								7%
AGAMREE [Member] | Royalty More Than Two Hundred Million And Less Than Three Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								9%
AGAMREE [Member] | Royalty More Than Three Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								11%
AGAMREE [Member] | Royalty Less Than Two Hundred Fifty Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								7%
AGAMREE [Member] | Royalty More Two Hundred And Fifty Million And Less Than Five Hundred Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								8.50%
AGAMREE [Member] | Royalty More Than Five Hundred Million And Less Than Seven Hundred Fifty Million [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								10%
AGAMREE [Member] | Royalty More Seven Hundred And Fifty Million And Less Than One Billion [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								12%
AGAMREE [Member] | Royalty More Than One Billion And Less Than Two Billion [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								13%
AGAMREE [Member] | Royalty More Than Two Billion [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								15%
AGAMREE [Member] | Royalty For Santhera Sales Based Milestones [Member]
License Agreement [Line Items]
Net sales based milestone to royalty threshold								$ 105,000
AGAMREE [Member] | Royalty For Additional Indications And Milestones Of Up To Fifty Million More [Member]
License Agreement [Line Items]
Percentage of royalty payable to sales based milestone								11%
AGAMREE [Member] | Royalty For Additional Indications And Milestones [Member]
License Agreement [Line Items]
Contingent consideration liability								$ 50,000
Minimum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								10,000
Minimum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Net sales royalty threshold								10,000
Minimum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								100,000
Minimum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Net sales royalty threshold								100,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than Hundred Million And Less Than Two Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								100,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than Two Hundred Million And Less Than Three Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								200,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than Three Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								300,000
Minimum [Member] | AGAMREE [Member] | Royalty Less Than Two Hundred Fifty Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								250,000
Minimum [Member] | AGAMREE [Member] | Royalty More Two Hundred And Fifty Million And Less Than Five Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								250,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than Five Hundred Million And Less Than Seven Hundred Fifty Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								500,000
Minimum [Member] | AGAMREE [Member] | Royalty More Seven Hundred And Fifty Million And Less Than One Billion [Member]
License Agreement [Line Items]
Net sales royalty threshold								750,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than One Billion And Less Than Two Billion [Member]
License Agreement [Line Items]
Net sales royalty threshold								1,000,000
Minimum [Member] | AGAMREE [Member] | Royalty More Than Two Billion [Member]
License Agreement [Line Items]
Net sales royalty threshold								2,000,000
Maximum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								100,000
Maximum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Ten Million And Less Than Hundred Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Net sales royalty threshold								100,000
Maximum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								125,000
Maximum [Member] | U.S. Rights for FYCOMPA [Member] | Royalty More Than Hundred Million And Less Than Hundred And Twenty Five Million [Member] | Royalty Agreement Terms [Member]
License Agreement [Line Items]
Net sales royalty threshold								125,000
Maximum [Member] | AGAMREE [Member] | Royalty Less Than Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								100,000
Maximum [Member] | AGAMREE [Member] | Royalty More Than Hundred Million And Less Than Two Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								200,000
Maximum [Member] | AGAMREE [Member] | Royalty More Than Two Hundred Million And Less Than Three Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								300,000
Maximum [Member] | AGAMREE [Member] | Royalty More Two Hundred And Fifty Million And Less Than Five Hundred Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								500,000
Maximum [Member] | AGAMREE [Member] | Royalty More Than Five Hundred Million And Less Than Seven Hundred Fifty Million [Member]
License Agreement [Line Items]
Net sales royalty threshold								750,000
Maximum [Member] | AGAMREE [Member] | Royalty More Seven Hundred And Fifty Million And Less Than One Billion [Member]
License Agreement [Line Items]
Net sales royalty threshold								1,000,000
Maximum [Member] | AGAMREE [Member] | Royalty More Than One Billion And Less Than Two Billion [Member]
License Agreement [Line Items]
Net sales royalty threshold								$ 2,000,000
License Agreement with BioMarin [Member]
License Agreement [Line Items]
Date on which strategic collaboration is entered into								Oct. 26, 2012
Royalty agreement period								7 years
Net sales royalty threshold								$ 100,000
License Agreement with BioMarin [Member] | Minimum [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								7%
License Agreement with BioMarin [Member] | Maximum [Member]
License Agreement [Line Items]
Percentage of royalty on net sales								10%
License Agreement For RUZURGI [Member]
License Agreement [Line Items]
Date on which strategic collaboration is entered into								Jul. 11, 2022
Minimum royalty	$ 3,000	$ 3,000		$ 3,000
Research and development expenses					$ 4,100
Up front payment					$ 10,000
Asset acquisition purchase price consideration		$ 10,000		$ 10,000
License Agreement For RUZURGI [Member] | Minimum [Member]
License Agreement [Line Items]
Percentage of minimum royalty payable to net sales								1.25%
License Agreement For RUZURGI [Member] | Maximum [Member]
License Agreement [Line Items]
Percentage of maximum royalty payable to net sales								2.50%

Agreements - Schedule Of Total

Agreements - Schedule Of Total Purchase Price Was Allocated To The Acquired Assets Based On Their Relative Fair Values (Detail) - License Agreement For RUZURGI [Member] $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($)
Schedule Of Total Purchase Price Was Allocated To The Acquired Assets Based On Their Relative Fair Values [Line Items]
License and acquired intangibles	$ 33,569
Acquired research and development inventory expensed from asset acquisition	4,130
Total purchase price	$ 37,699

Agreements - Summary of Aggrega

Agreements - Summary of Aggregate Amount Paid for the Assets Acquired (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($)
Asset Acquisition [Line Items]
Total purchase consideration	$ 94,978
U.S. Rights for FYCOMPA [Member]
Asset Acquisition [Line Items]
Base cash payment	160,000
Cash paid for pro-rated prepaid expenses	1,576
Reimbursement on base purchase price	(3,238)	[1]
Transaction costs	5,870	[2]
Total purchase consideration	$ 164,208
[1]Recorded in prepaid expenses and other current assets in the accompanying consolidated balance sheet as of the acquisition date and reimbursement was fully applied as of June 30, 2023.[2]As of March 31, 2024, the full $5.9 million has been paid in cash.

Agreements - Summary of Aggre_2

Agreements - Summary of Aggregate Amount Paid for the Assets Acquired (Parenthetical) (Detail) - U.S. Rights for FYCOMPA [Member] $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($)
Asset Acquisition [Line Items]
Transaction expenses	$ 5,870	[1]
Cash [Member]
Asset Acquisition [Line Items]
Transaction expenses	$ 5,900
[1]As of March 31, 2024, the full $5.9 million has been paid in cash.

Agreements - Summary of Total P

Agreements - Summary of Total Purchase Price Allocated to Acquired Assets (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($)
Asset Acquisition [Line Items]
Total purchase consideration	$ 94,978
U.S. Rights for FYCOMPA [Member]
Asset Acquisition [Line Items]
Inventory	4,100
Prepaid expenses and other current assets (samples)	130
Prepaid commercialization expenses	1,576
Property and equipment, net	433
License and acquired intangibles for FYCOMPA®	158,143
Accrued preclinical and clinical trial expenses	(174)
Total purchase consideration	$ 164,208

Agreements - Summary of aggre_3

Agreements - Summary of aggregate amount paid for the assets (Detail) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended
		Jul. 31, 2023	Mar. 31, 2024
Asset Acquisition [Line Items]
Investment in Santhera	[1]		$ 13,465
Total purchase consideration			$ 94,978
Vamorolone [Member]
Asset Acquisition [Line Items]
Initial cash payment		$ 75,000
Investment in Santhera		13,465
Transaction costs		6,513
Total purchase consideration		$ 94,978
[1]The fair value of the investment in Santhera was determined based on the closing market price (CHF 8.25) of Santhera shares and the exchange rate (1.1537) of CHF to USD on the date the shares were transferred, July 19, 2023.

Agreements - Summary of total_2

Agreements - Summary of total purchase price allocated (Detail) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended
		Jul. 31, 2023	Mar. 31, 2024
Asset Acquisition [Line Items]
Investment in Santhera	[1]		$ 13,465
Total purchase consideration			94,978
Vamorolone [Member]
Asset Acquisition [Line Items]
License and acquired intangibles for vamorolone (IPR&D)			$ 81,513
Investment in Santhera		$ 13,465
Total purchase consideration		$ 94,978
[1]The fair value of the investment in Santhera was determined based on the closing market price (CHF 8.25) of Santhera shares and the exchange rate (1.1537) of CHF to USD on the date the shares were transferred, July 19, 2023.

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Income Tax Disclosure [Line Items]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 0		$ 0
Effective Income Tax Rate Reconciliation, Percent	20%	20.80%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21%

Stockholders' Equity (Preferred

Stockholders' Equity (Preferred Stock and Common Stock) - Additional Information (Detail)	Mar. 31, 2024 Vote $ / shares shares	Dec. 31, 2023 $ / shares shares
Stockholders Equity [Line Items]
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, par value | $ / shares	$ 0.001	$ 0.001
Preferred stock, shares outstanding	0	0
Common stock, shares authorized	200,000,000	200,000,000
Common stock, par value | $ / shares	$ 0.001	$ 0.001
Common stock, shares issued	118,029,526	107,121,549
Common stock, shares outstanding	118,029,526	107,121,549
Number of votes entitled for each share of common stock | Vote	1

Stockholders' Equity ( Share Re

Stockholders' Equity ( Share Repurchases ) - Additional Information (Detail) - Common Stock [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2021
Stockholders Equity [Line Items]
Aggregate share repurchased	0	0
Share Purchase Program [Member]
Stockholders Equity [Line Items]
Share repurchase program, authorised			$ 40

Stockholders' Equity (2020 Shel

Stockholders' Equity (2020 Shelf Registration Statement) - Additional Information (Detail) $ in Millions	Jul. 23, 2020 USD ($)
2020 Shelf Registration Statement [Member]
Stockholders' Equity [Line Items]
Maximum dollar amount of common stock to be issued under shelf registration statement	$ 200

Stockholders' Equity (2023 Shel

Stockholders' Equity (2023 Shelf Registration Statement) - Additional Information (Detail) - USD ($)		3 Months Ended
	Jan. 09, 2024	Mar. 31, 2024	Mar. 31, 2023	Sep. 08, 2023
Stockholders' Equity [Line Items]
Gross proceeds from issuance of common stock		$ 141,000,000	$ 0
2023 Shelf Registration Statement [Member]
Stockholders' Equity [Line Items]
Maximum dollar amount of common stock to be issued under shelf registration statement				$ 500,000,000
Stock issued during the period shares new issues	10,000,000
Gross proceeds from issuance of common stock	$ 140,700,000

Stock Compensation - Stock-Base

Stock Compensation - Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 8,248	$ 2,892
Research and Development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	509	339
Selling, General and Administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 7,739	$ 2,553

Stock Compensation - Additional

Stock Compensation - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from exercise of stock options	$ 1,522	$ 1,270
Number of options, Outstanding	14,241,187
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to non-vested stock compensation awards granted under the Plan	$ 7,800
Expected remaining weighted average vesting period	3 years 1 month 6 days
Non-cash stock-based compensation expense	$ 2,900	$ 700
Common stock granted	35,693	0
Options to Purchase Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options exercised	664,432	547,957
Proceeds from exercise of stock options	$ 1,500	$ 1,300
Stock option granted, contractual term	7 years	7 years
Common stock unit granted	793,495	340,500
Unrecognized compensation expense related to non-vested stock compensation awards granted under the Plan	$ 36,400
Expected remaining weighted average vesting period	3 years 1 month 6 days
Non-cash stock-based compensation expense	$ 5,400	$ 2,200
Stock options to purchase shares of common stock	8,869,384