QNTM amends Form 6-K to fix Exhibit 99.1 description only

Rhea-AI Filing Summary

Quantum Biopharma Ltd. filed an amended Form 6-K to correct an administrative error in the exhibit index of a prior submission. The amendment updates the description of Exhibit 99.1 only and states it does not modify or update any other disclosures from the original report.

Exhibit 99.1 is identified as a press release dated January 29, 2024 regarding FSD Pharma board changes and corporate updates. The filing was executed on behalf of the company by Chief Financial Officer Donal Carroll.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K/A

Amendment No. 1

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

OF THE SECURITIES EXCHANGE ACT OF 1934

For the month of October 2025

Commission File Number: 001-39152

QUANTUM BIOPHARMA LTD.

(Registrant)

1 Adelaide Street East, Suite 801

Toronto, Ontario M5C 2V9

(Address of Principal Executive Offices)

Indicate by check mark whether the Registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F  ☒            Form 40-F  ☐

Indicate by check mark if the Registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):  ☐

Indicate by check mark if the Registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):  ☐

EXPLANATORY NOTE

On February 7, 2024, Quantum Biopharma Ltd. (the "Company") furnished a report on Form 6-K, Accession No. 0001654954-24-001448 (the "Original Report"). Due to an administrative error, an incorrect description of Exhibit 99.1 in the exhibit index was furnished with the Original Report. This Amendment No. 1 to the Original Report on Form 6-K (this "Amendment") is being furnished solely to furnish the correct the description of Exhibit 99.1 in the exhibit index. Except as specifically described in this explanatory note, this Amendment does not reflect events that may have occurred subsequent to the original submission date and does not modify or update in any way the disclosures made in the Original Report.

SIGNATURES

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

	QUANTUM BIOPHARMA LTD.
	(Registrant)
Date October 28, 2025	By	/s/ Donal Carroll
		Donal Carroll
		Chief Financial Officer

EXHIBIT INDEX

Exhibit		Description of Exhibit
99.1		Press Release dated January 29, 2024 - FSD Pharma Announces Dr. Sanjiv Chopra is elected to FSD Pharma Board of Directors and Corporate Updates

FAQ

What did Quantum Biopharma (QNTM) change in this Form 6-K/A?

It corrected an administrative error by updating the description of Exhibit 99.1 in the exhibit index.

Does this amendment change any prior disclosures for QNTM?

No. The amendment states it does not modify or update disclosures made in the original report.

What is Exhibit 99.1 in Quantum Biopharma’s filing?

Exhibit 99.1 is a Press Release dated January 29, 2024 titled “FSD Pharma Announces Dr. Sanjiv Chopra is elected to FSD Pharma Board of Directors and Corporate Updates.”

Why was the Form 6-K/A necessary for QNTM?

An administrative error led to an incorrect description of Exhibit 99.1 in the original Form 6-K, prompting this amendment.

Who signed the amended filing for Quantum Biopharma?

It was signed by Donal Carroll, Chief Financial Officer.