As filed with the Securities and Exchange Commission on May 31, 2024

Registration No. 333-275963

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

POST-EFFECTIVE AMENDMENT NO. 1

TO

FORM S-8

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

CATALYST PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

2018 Stock Incentive Plan

(Full title of the plan)

Richard J. Daly

355 Alhambra Circle

Suite 801

Coral Gables, Florida 33134

(Name and address of agent for service)

(305) 420-3200

(Telephone number, including area code, of agent for service)

With a copy to:

Philip B. Schwartz, Esq.

Andrew E. Schwartz, Esq.

Akerman LLP

201 East Las Olas Boulevard

Suite 1800

Fort Lauderdale, Florida 33301

(954) 463-2700

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

EXPLANATORY NOTE

Catalyst Pharmaceuticals, Inc. (the “Company”) is filing this Post-Effective Amendment No. 1 to the Company’s Registration Statement on Form S-8 (File No. 333-275963) for the purpose of providing the auditor consent that was inadvertently omitted from the original filing, which consent is attached hereto as Exhibit 23.2. Other than the addition of the exhibit and the corresponding change to the exhibit index, the remainder of this Registration Statement remains unchanged.

This Post-Effective Amendment No. 1 does not reflect events occurring after the effective date of the Company’s Registration Statement or modify or update the disclosures therein in any way other than as required to reflect the amendment set forth below.

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PART II

INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

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provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) shall not apply if the information required to be included on a post-effective amendment by those paragraphs is contained in periodic reports filed by or furnished to the Commission by the Company pursuant to Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in this Registration Statement.

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, as amended, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this Post-Effective Amendment No. 1 to Registration Statement to be signed on behalf of the undersigned, thereunto authorized, in the City of Coral Gables, State of Florida, on the 31^st day of May, 2024.

Each person whose signature appears below hereby constitutes and appoints Richard J. Daly and Michael W. Kalb, and each of them, as their true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution for him and in his name, place, and stead, in any and all capacities, to sign any or all amendments or supplements to this registration statement, whether pre-effective or post-effective, including any subsequent registration statement for the same offering which may be filed under Rule 462(b) under the Securities Act of 1933, as amended, to file the same with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing necessary or appropriate to be done with respect to this registration statement or any amendments or supplements hereto in the premises, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming that all said attorneys-in-fact and agents, or any of them, or this or his substitute or substitutes, may lawfully do or cause to be done by virtue thereof.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons, in the capacities and on the dates indicated.

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Exhibit 23.2

CONSENT OF INDEPENDENT AUDITORS

We consent to the incorporation by reference in this Registration Statement No. 333-275963 on Form S-8 of our report dated April 10, 2023 relating to the abbreviated financial statements of FYCOMPA PRODUCT LINE OF EISAI CO., LTD. AND SUBSIDIARIES appearing in the Current Report on Form 8-K of Catalyst Pharmaceuticals, Inc filed on April 10, 2023.

/s/ Deloitte & Touche LLP

Morristown, NJ

May 31, 2024