UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): June 12, 2025

Equillium, Inc.

(Exact name of Registrant as Specified in Its Charter)

Registrant’s Telephone Number, Including Area Code: (858) 240-1200

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 (see General Instruction A.2. below):

☐ 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 CFR 240.14d-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:

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. ☐

Item 3.01 Notice of Delisting or Failure to Satisfy a Continued Listing Rule or Standard; Transfer of Listing.

As previously disclosed, on December 13, 2024, Equillium, Inc. (the “Company”) received a notice from The Nasdaq Stock Market LLC (“Nasdaq”) that the Company was not in compliance with Nasdaq Listing Rule 5550(a)(2) because the minimum bid price of the Company’s common stock had been below $1.00 per share for the previous 30 consecutive business days (the “Minimum Bid Price Requirement”). The Company was given 180 days, or until June 11, 2025, to regain compliance with the Minimum Bid Price Requirement.

On June 12, 2025, the Company received a notice from Nasdaq that the Company was granted an additional 180 calendar days, until December 8, 2025, to regain compliance with the Minimum Bid Price Requirement. The notice from Nasdaq states that if compliance with the Minimum Bid Price Requirement cannot be demonstrated by December 8, 2025, Nasdaq staff will provide written notification that the Company’s common stock will be delisted. At that time, the Company may appeal Nasdaq staff’s determination to a Nasdaq hearings panel.

The Company intends to actively monitor the bid price of its common stock and will consider available options to regain compliance with the Minimum Bid Price Requirement, including such actions as a reverse stock split. The notification of noncompliance has no immediate effect on the listing or trading of the Company’s common stock on the Nasdaq Capital Market and the Company’s common stock continues to trade on the Nasdaq Capital Market under the symbol “EQ.”

Forward-Looking Statements

This report contains forward-looking statements within the meaning of the U.S. Private Securities Litigation Reform Act of 1995. Any statements in this report that are not historical facts may be considered “forward-looking statements”. Forward-looking statements are typically, but not always, identified by the use of words such as “may,” “would,” “believe,” “intend,” “plan,” “anticipate,” “estimate,” “expect,” and other similar terminology. Forward-looking statements are based on current expectations of management and upon what management believes to be reasonable assumptions based on information currently available to it, and are subject to risks and uncertainties. Such risks and uncertainties may cause actual results to differ materially from the expectations set forth in the forward-looking statements. Such risks and uncertainties include, but are not limited to, risks related to preliminary financial results, including the risks that the preliminary financial results reported herein reflect information available to the Company only at this time and may differ from actual results, including in connection with the Company’s completion of financial closing procedures, risks and uncertainties associated with the Company’s business and finances in general, as well as other risks detailed in the Company’s recent filings on Forms 10-K and 10-Q with SEC. The Company undertakes no obligation to update any forward-looking statements to reflect new information, events or circumstances, or to reflect the occurrence of unanticipated events.

SIGNATURE

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 hereunto duly authorized.