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(Amendment No.   )

Filed by the Registrant x

Filed by a Party other than the Registrant ¨

Check the appropriate box:

¨ Preliminary Proxy Statement

¨ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

¨ Definitive Proxy Statement

x Definitive Additional Materials

¨ Soliciting Material under §240.14a-12

IMMUNOME, INC.

(Name of Registrant as Specified In Its Charter)

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

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

x No fee required

¨ Fee paid previously with preliminary materials

¨ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11

Your Vote Counts! IMMUNOME, INC. 2023 Annual Meeting Vote by June 6, 2023 11:59 PM ET You invested in IMMUNOME, INC. and it’s time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy materials for the stockholder meeting to be held at 1:00 PM Eastern Time on June 7, 2023 virtually at www.virtualshareholdermeeting.com/IMNM2023. Vote Virtually at the Meeting* June 7, 2023 1:00 p.m. Eastern Time Virtually at: www.virtualshareholdermeeting.com/IMNM2023 *Please check the meeting materials for any special requirements for meeting attendance. Smartphone users Point your camera here and vote without entering a control number For complete information and to vote, visit www.ProxyVote.com Control # V10806-P92715 Get informed before you vote View the Notice and Proxy Statement and Annual Report online OR you can receive a free paper or email copy of the material(s) by requesting prior to May 24, 2023. If you would like to request a copy of the material(s) for this and/or future stockholder meetings, you may (1) visit www.ProxyVote.com, (2) call 1-800-579-1639 or (3) send an email to sendmaterial@proxyvote.com. If sending an email, please include your control number (indicated below) in the subject line. Unless requested, you will not otherwise receive a paper or email copy. IMMUNOME, INC. 665 STOCKTON DRIVE SUITE 300 EXTON, PA 19341 V1.2

THIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming stockholder meeting. Please follow the instructions on the reverse side to vote these important matters. Vote at www.ProxyVote.com Prefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click “Delivery Settings”. Voting Items Board Recommends V10807-P92715 01) Richard A. Baron 02) Philip Wagenheim 1. Election of Two Class III Directors for a Three-Year Term Expiring in 2026 Nominees: 2. To approve a proposed amendment to the Company’s Amended and Restated Certificate of Incorporation to reflect new Delaware law provisions regarding officer exculpation. 3. To ratify the appointment of Ernst & Young LLP as the Company’s independent registered public accounting firm for the year ending December 31, 2023. NOTE: In their discretion, the proxies are authorized to vote upon such other matters which may properly come before the annual meeting or any adjournments or postponements thereof. For For For