Equillium, Inc.

NASDAQ false 0001746466 0001746466 2026-10-26 2026-10-26 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): October 26, 2026 Equillium, Inc. (Exact name of Registrant as Specified in Its Charter) Delaware 001-38692 82-1554746 (State or Other Jurisdiction of Incorporation) (Commission File Number) (IRS Employer Identification No.) 2223 Avenida de la Playa Suite 105 La Jolla , California 92037 (Address of Principal Executive Offices) (Zip Code) Registrant’s Telephone Number, Including Area Code: (858) 240-1200 (Former Name or Former Address, if Changed Since Last Report) Not Applicable 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 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: Title of each class Trading Symbol(s) Name of each exchange on which registered Common Stock, $0.0001 par value per share EQ The Nasdaq Capital Market 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 3.02 Unregistered Sales of Equity Securities. The disclosure regarding the securities sold and issued under the Securities Purchase Agreement by and among Equillium, Inc., a Delaware corporation (the “Company”) and certain institutional and accredited investors (the “Investors”), dated August 10, 2025 (the “Purchase Agreement”) set forth under Item 8.01 of this Current Report on Form 8-K is incorporated by reference under this Item 3.02. The Company expects to use the net proceeds from the Milestone Closing (as defined below) of the Private Placement (as defined below), together with the Company’s existing cash and cash equivalents, to fund the development of EQ504, as well as for working capital and other general corporate purposes. The securities described below under Item 8.01 have not been registered under the Securities Act of 1933, as amended (“Securities Act”), or any state securities laws. The Company is relying on the exemption from the registration requirements of the Securities Act by virtue of Section 4(a)(2) thereof. Each of the Investors provided representations appropriate for a private placement of securities. Restrictive legends will be affixed to the securities issued in the Private Placement. Neither this Current Report on Form 8-K nor any exhibit attached hereto is an offer to sell or the solicitation of an offer to buy shares of common stock or other securities of the Company. Item 7.01 Regulation FD Disclosure. On October 26, 2026, the Company issued a press release announcing the dosing of its first patient in its single ascending dose trial of EQ504 in Australia and the achievement of the Milestone Event (as defined below). The press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K and incorporated into this Item 7.01 by reference. The information in Item 7.01 of this Current Report on Form 8-K shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act or the Exchange Act, except as expressly set forth by specific reference in such a filing. Item 8.01 Other Events. As previously disclosed by the Company in the Current Report on Form 8-K filed with the U.S. Securities and Exchange Commission (the “SEC”) on August 11, 2025 (the “Private Placement 8-K”), on August 10, 2025, the Company entered into the Purchase Agreement with the Investors, pursuant to which the Company agreed to sell and issue shares (“Shares”) of the Company’s common stock, par value $0.0001 (“Common Stock”), and pre-funded warrants to purchase shares of Common Stock (“Warrant Shares”), in up to two closings in a private placement transaction (the “Private Placement”). Pursuant to the Purchase Agreement and subject to the occurrence of (i) the Milestone Event (as defined below) and (ii) either (x) the price of a share of the Company’s Common Stock maintaining a $2.50 weighted average price for 10 consecutive days during a 30 day measurement period (the “Price Threshold Requirement”) or (y) the Company’s receipt of a waiver of the Price Threshold Requirement from the Investors who held a majority of the securities sold at the initial closing in the Private Placement, the Investors agreed to purchase at a closing (the “Milestone Closing”) up to 35,087,717 Shares or pre-funded warrants in lieu thereof at a purchase price per Share of $0.57 (the “Share Price”) or per pre-funded warrant of $0.5669 (the “Warrant Price”), for gross proceeds to the Company of up to approximately $20.0 million. The Company announced that it had dosed the first patient in a single ascending dose trial of EQ504 in Australia (the “Milestone Event”) on October 26, 2026 (the “Milestone Event Date”). Also on October 26, 2026, the requisite Investors waived the Price Threshold Requirement and consented to causing the Milestone Closing to occur on the Milestone Event Date. At the Milestone Closing, the Company issued and sold 14,957,260 Shares at the Share Price and 20,130,457 pre-funded warrants at the Warrant Price. The Milestone Closing resulted in aggregate gross proceeds to the Company of $20.0 million, before deducting fees and other expenses. The pre-funded warrants have an exercise price of $0.0001 per Warrant Share, subject to customary adjustments, and will be exercisable at any time after original issuance and will not expire until exercised in full. The pre-funded warrants will also be exercisable on a net exercise “cashless” basis. The pre-funded warrants may not be exercised if the aggregate number of shares of Common Stock beneficially owned by the holder thereof immediately following such exercise would exceed a specified beneficial ownership limitation, not to exceed 19.99%. The securities issued in the Milestone Closing are subject to the Registration Rights Agreement, dated August 12, 2025, previously entered into in connection with the Purchase Agreement and disclosed by the Company in the Private Placement 8-K. The Company has agreed to prepare and file, within 30 days of the Milestone Closing, subject to certain allowable delays, one or more registration statements with the SEC to register for resale the Common Stock and, as applicable, the Warrant Shares, in each case that were issued under the Purchase Agreement, and generally to cause the applicable registration statements to promptly become effective. Certain cash penalties will apply to the Company in the event of registration failures, as described in the Registration Rights Agreement. The foregoing summary of the pre-funded warrants does not purport to be complete and is qualified in its entirety by reference to the complete text of the form of pre-funded warrant, which was previously filed as Exhibit 4.2 to the Private Placement 8-K. Forward-Looking Statements This Cur