Form 8-K

8-K — Tempest Therapeutics, Inc.

Accession: 0001213900-26-111026

Filed: 2026-10-20

Period: 2026-10-14

CIK: 0001544227

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Submission of Matters to a Vote of Security Holders

Item: Other Events

Documents

8-K — ea0309080-8k_tempest.htm (Primary)

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8-K — CURRENT REPORT

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UNITED

STATES

SECURITIES

AND EXCHANGE COMMISSION

WASHINGTON,

D.C. 20549

FORM

8-K

CURRENT

REPORT

Pursuant

to Section 13 or 15(d)

the Securities Exchange Act of 1934

Date

of Report (Date of earliest event reported): October 14, 2026

Tempest Therapeutics, Inc.

(Exact

name of Registrant as Specified in Its Charter)

Delaware

001-35890

45-1472564

(State or Other Jurisdiction

of Incorporation)

(Commission File Number)

(IRS Employer

Identification No.)

2000 Sierra Point Parkway, Suite 400

Brisbane, California

94005

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s Telephone Number, Including

Area Code: (415) 798-8589

(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 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, $0.001 par value

TPST

The Nasdaq Stock Market LLC

Series A Junior Participating Preferred Purchase Rights

N/A

The Nasdaq Stock Market LLC

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 5.07.

Submission of Matters to a Vote of Security Holders.

The information disclosed in Item 8.01 of this

Current Report on Form 8-K is incorporated herein by reference.

Item 8.01.

Other Events.

On October 14, 2026, Tempest Therapeutics,

Inc. (the “Company”) called to order its reconvened special meeting of stockholders (the “Special Meeting”) originally

convened and adjourned on July 27, 2026. The Special Meeting had previously been reconvened and adjourned on August 17, 2026, and September

15, 2026. The purpose of the Special Meeting is to approve a Certificate of Amendment to the Company’s Restated Certificate of Incorporation

to replace specified supermajority voting requirements and permit stockholder action by written consent in the form attached as Exhibit A to

the proxy statement previously distributed to the Company’s stockholders in connection with the Special Meeting (the “Proposal”).

At the Special Meeting, a total of 11,004,101 shares,

or 74.3% of the 14,806,997 shares of common stock outstanding as of May 28, 2026, the record date for the Special Meeting, were

present virtually or represented by proxy, constituting a quorum. However, because there were not sufficient votes to approve the Proposal

at the time of the Special Meeting, the Company decided to adjourn the Special Meeting to provide stockholders with additional time to

vote and to facilitate broader participation.

The Special Meeting will reconvene on November 12,

2026 at 2:00 p.m. Eastern Time via live webcast at the following virtual meeting link, www.virtualshareholdermeeting.com/TPST2026SM2.

Stockholders can use the same access code to attend the reconvened meeting on November 12, 2026 that was used for the originally scheduled

Special Meeting convened on July 27, 2026.

The Proposal requires the affirmative vote of

the holders of at least seventy-five percent (75%) of the votes that all the stockholders would be entitled to cast in any annual election

of directors or class of directors.

No changes have been made to the Proposal to be

voted on by the stockholders at the Special Meeting. The record date for determining stockholder eligibility to vote at the Special Meeting

remains the close of business on May 28, 2026. Proxies previously submitted will be voted at the reconvened Special Meeting unless

properly revoked, and stockholders who have already submitted a proxy or otherwise voted and do not wish to change their vote need not

take any action.

Important Additional Information and Where to Find It:

The Company has filed a definitive proxy statement

and other relevant documents with the U.S. Securities and Exchange Commission (“SEC”) in connection with the Special Meeting.

INVESTORS AND SECURITY HOLDERS ARE URGED TO READ THE DEFINITIVE PROXY STATEMENT AND OTHER RELEVANT DOCUMENTS FILED WITH THE SEC CAREFULLY

AND IN THEIR ENTIRETY because they contain important information about the matters to be voted on at the Special Meeting. Stockholders

may obtain copies of these documents free of charge at the SEC’s website at www.sec.gov or on the Company’s website at https://www.tempesttx.com.

Participants in the Solicitation:

The Company and its directors and executive officers

may be deemed to be participants in the solicitation of proxies from the Company’s stockholders in connection with the Special Meeting.

Information about the Company’s directors and executive officers is outlined in the Company’s Annual Report on Form 10-K for

the year ended December 31, 2025, filed with the SEC on March 30, 2026, as updated by the Company’s Current Report on Form 8-K filed

with the SEC on June 4, 2026, the Company’s Current Report on Form 8-K filed with the SEC on August 24, 2026, the Company’s

Current Report on Form 8-K filed with the SEC on September 28, 2026, the Company’s Current Report on Form 8-K filed with the SEC

on October 19, 2026, and information about their ownership of the Company’s common stock is outlined in the definitive proxy statement

for the Special Meeting filed with the SEC on July 17, 2026. The Company has also engaged Sodali & Co., a proxy solicitation firm,

to assist with obtaining adequate votes to achieve the required quorum of a majority of the outstanding shares of the Company’s

common stock entitled to vote at the Special Meeting.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934,

as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

TEMPEST THERAPEUTICS, INC.

Date: October 20, 2026

By:

/s/ Matthew Angel

Name:

Matthew Angel

Title:

President and Chief Executive Officer

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