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.     )

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Phathom Pharmaceuticals, Inc.

(Name of Registrant as Specified In Its Charter)

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

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Your Vote Counts!PHATHOM PHARMACEUTICALS, INC.100 CAMPUS DRIVE, SUITE 102FLORHAM PARK, NJ 07932PHATHOM PHARMACEUTICALS, INC.2021 Annual MeetingVote by May 20, 202111:59 PM ETYou invested in PHATHOM PHARMACEUTICALS, 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 material for the shareholder meeting to be held on May 21, 2021.Vote Virtually at the Meeting*May 21, 202110:45 AM EDTVirtually at:www.virtualshareholdermeeting.com/PHAT2021*Many shareholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting.      Please check the meeting materials for any special requirements for meeting attendance.

Smartphone usersPoint your camera here and vote without entering a control numberV1For complete information and to vote, visit www.ProxyVote.com Control #D36154-P48778Get informed before you voteView the Annual Report and Notice & Proxy Statement online OR you can receive a free paper or email copy of the material(s) by requesting prior to May 7, 2021. If you would like to request a copy of the material(s) for this and/or future shareholder 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.THIS IS NOT A VOTABLE BALLOTThis is an overview of the proposals being presented at the upcoming shareholder meeting. Please follow the instructions on the reverse side to vote these important matters.Vote at www.ProxyVote.comPrefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click “Sign up for E-delivery”.Voting ItemsBoard RecommendsD36155-P487781.   To elect two class II directors to hold office until the 2024 Annual Meeting of Shareholders.      Nominees:1a.  Michael F. Cola2.   To ratify the appointment of Ernst & Young LLP as Phathom’s independent registered public accounting firm for the fiscal year ending December 31, 2021.1b. Asit Parikh, M.D., Ph.D.NOTE: Such other business as may properly come before the meeting or any adjournment thereof.ForForFor