Patent trial on Catalyst (NASDAQ: CPRX) FIRDAPSE® patents delayed to May 18, 2026

Rhea-AI Filing Summary

Catalyst Pharmaceuticals, Inc. filed an amended current report to correct a scrivener’s error in the signature date of a previously submitted report. No other changes were made.

The company also notes that a federal court in New Jersey has delayed the start of a bench trial with Hetero USA, Inc. concerning the validity of its Orange Book-listed FIRDAPSE® patents, which expire in 2032, 2034, and 2037, moving the trial start from March 23, 2026 to May 18, 2026.

Insights

Biopharma litigation and IP analyst

Amended report is administrative, but trial timing on key FIRDAPSE patents has shifted.

The amendment itself is purely administrative, correcting only a signature date and leaving all prior disclosures unchanged. By contrast, the referenced court order alters the schedule for a bench trial over Orange Book-listed FIRDAPSE® patents expiring in 2032, 2034, and 2037.

This litigation concerns patent validity, which can be important for future market exclusivity, but the excerpt only shows a timing change: the bench trial is delayed from March 23, 2026 to May 18, 2026. The actual impact will depend on the eventual court outcome, which is not addressed here.

NASDAQ true 0001369568 0001369568 2026-03-18 2026-03-18

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K/A

(Amendment No. 1)

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of Earliest Event Reported): March 18, 2026

CATALYST PHARMACEUTICALS, INC.

(Exact Name Of Registrant As Specified In Its Charter)

Delaware		001-33057		76-0837053
(State or other jurisdiction of incorporation)		(Commission File Number)		(I.R.S. Employer Identification No.)
355 Alhambra Circle
Suite 801
Coral Gables, Florida				33134
(Address of principal executive offices)				(Zip Code)

Registrant’s telephone number, including area code: (305) 420-3200

Not Applicable

Former Name or Former address, if changed since last report

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of Each Class		Name of Exchange on Which Registered		Ticker Symbol
Common Stock, par value $0.001 per share		NASDAQ Capital Market		CPRX

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this Chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging Growth Company ☐

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 13(a) of the Exchange Act. ☐

EXPLANATORY NOTE

This Amendment No. 1 to Form 8-K is being filed to correct a scrivener’s error in the signature date of the Company’s Current Report on Form 8-K filed with the SEC on March 18, 2026. Other than that correction, no other changes are made to the previously filed Form 8-K.

Item 8.01 Other Events

On March 18, 2026, the District Court for the District of New Jersey filed an order delaying the start of the bench trial between the Company and Hetero USA, Inc. from March 23, 2026 until May 18, 2026. The bench trial relates to the validity of the Company’s Orange Book-listed patents related to FIRDAPSE^® that expire in 2032, 2034, and 2037.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Catalyst Pharmaceuticals, Inc.
By:		/s/ Michael W. Kalb
		Michael W. Kalb
		Executive Vice President and Chief Financial Officer

Dated: March 18, 2026

3

FAQ

What is Catalyst Pharmaceuticals (CPRX) changing with this 8-K/A amendment?

The amendment only corrects a scrivener’s error in the signature date of a previously filed report. All substantive disclosures remain the same, so there are no new financial, operational, or strategic updates in this amendment.

How does the court order affect Catalyst Pharmaceuticals’ FIRDAPSE patents?

The court order delays the start of a bench trial on FIRDAPSE® patent validity. These Orange Book-listed patents currently run until 2032, 2034, and 2037, so the case timing may influence how long those protections ultimately remain in force.

When will Catalyst Pharmaceuticals’ FIRDAPSE patent bench trial now begin?

The bench trial between Catalyst Pharmaceuticals and Hetero USA, Inc. has been rescheduled to begin on May 18, 2026. It was originally set to start on March 23, 2026, so the order pushes the schedule back by nearly two months.

What is the dispute between Catalyst Pharmaceuticals and Hetero USA, Inc. about?

The bench trial concerns the validity of Catalyst’s Orange Book-listed patents related to FIRDAPSE®. These patents, expiring in 2032, 2034, and 2037, help protect the product from certain competition, making the litigation outcome potentially important for long-term exclusivity.

Does this Catalyst Pharmaceuticals 8-K/A include new financial or earnings information?

No, the amendment is limited to correcting the signature date of a prior report and restating that the bench trial start date has been delayed. It does not provide new earnings, revenue, or other financial performance metrics for Catalyst Pharmaceuticals.

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