Decoy Therapeutics Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

Decoy Therapeutics Inc.

(Name of Registrant as Specified in its Charter)

Not Applicable.

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

DECOY THERAPEUTICS INC.

2450 Holcombe Blvd.

Suite X

Houston, TX 77021

713-913-5608

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held July 14, 2026

To Our Stockholders:

NOTICE IS HEREBY GIVEN that Decoy Therapeutics Inc. will hold its 2026 Annual Meeting of Stockholders (the “Annual Meeting”) at 10:00 AM, CST, on Tuesday, July 14, 2026. This year’s Annual Meeting will be held solely by means of live audio webcast online athttps://web.viewproxy.com/dcoy/2026. For instructions on how to attend and vote your shares at the Annual Meeting, see the information in the accompanying Proxy Statement in the section titled “Information Concerning Voting and Solicitation - Questions and Answer About These Proxy Material and Voting.” The items of business for the meeting are to consider and vote on the following matters described in the accompanying proxy statement:

To elect three Class II directors to our Board of Directors (our “Board of Directors”), each to serve until our 2029 Annual Meeting of Stockholders or until their respective successors are duly elected and qualified (“Proposal 1”).

To approve, on a non-binding advisory basis, the compensation paid by us to our named executive officers as disclosed in the attached proxy statement (“Proposal 2”).

To ratify the appointment of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2026 (“Proposal 3”).

To transact such other business as may properly come before the Annual Meeting and any adjournments or postponements of the Annual Meeting.

The Board of Directors recommends that stockholders vote “FOR” each of the director nominees listed in Proposal 1 and “FOR” Proposals 2 and 3.

Only stockholders of record at the close of business on May 22, 2026 are entitled to notice of, and to vote while attending the Annual Meeting on the Internet.

We are using the “Notice and Access” method of providing proxy materials to you via the Internet. We are mailing to you a Notice of Internet Availability of Proxy Materials instead of paper copies of this Notice of 2026 Annual Meeting of Stockholders and Proxy Statement (this Notice and Proxy Statement) and our Annual Report on Form 10-K for the year ended December 31, 2025 (Annual Report), as amended. Notice and Access provides a convenient way for you to access our proxy materials. The Notice of Internet Availability of Proxy Materials includes instructions on how to access this Notice and Proxy Statement and our Annual Report and how to vote your shares. The Notice of Internet Availability of Proxy Materials also contains instructions on how to receive a paper copy of the proxy materials and our Annual Report, if you prefer.

The accompanying proxy statement includes further details with respect to the proposals to be considered at the Annual Meeting. This Notice and the accompanying proxy statement contain important information and should be read in their entirety. If you are in doubt as to how you should vote at the Annual Meeting, you should seek advice from your legal counsel, accountant or other professional adviser prior to voting.

By the Order of the Board of Directors

/s/ Frederick E. Pierce

Frederick E. Pierce

Chief Executive Officer and Director

Houston, Texas

June 4, 2026

Important Notice Regarding the Availability of Proxy Materials for the

Annual Meeting of Stockholders to be Held on July 14, 2026:

Copies of our Proxy Materials, consisting of the Notice of Annual Meeting of Stockholders, the Proxy Statement and Accompanying Form of Proxy Card, and our 2025 Annual Report on Form 10-K, as amended, are available at: https://web.viewproxy.com/dcoy/2026