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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☐ Definitive Proxy Statement

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Metacrine, Inc.

(Name of Registrant as Specified In Its Charter)

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METACRINE P.O. BOX 8016, CARY, NC 27512-9903 Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting To Be Held on May 24, 2021 For Stockholders as of March 29, 2021 This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. This is not a ballot. You cannot use this notice to vote your shares. We encourage you to access and review all of the important information contained in the proxy materials before voting. To view the proxy materials go to: www.proxydocs.com/MTCR To vote your proxy while visiting this site, you will need the 12 digit control number in the box below. Under United States Securities and Exchange Commission rules, proxy materials do not have to be delivered in paper. Proxy materials can be distributed by making them available on the Internet. CONTROL NUMBER For a convenient way to view proxy materials and VOTE go to www.proxydocs.com/MTCR Have the 12 digit control number located in the shaded box above available when you access the website and follow the instructions. If you want to receive a paper or e-mail copy of the proxy material, you must request one. There is no charge to you for requesting a copy. In order to receive a paper package in time for this year’s stockholder meeting, you must make this request on or before May 12, 2021. To order paper materials, use one of the following methods. INTERNET www.investorelections.com/MTCR TELEPHONE (866) 648-8133 * E-MAIL paper@investorelections.com When requesting via the internet or telephone you will need the 12 digit control number located in the shaded box above. * If requesting material by e-mail, please send a blank e-mail with the 12 digit control number (located above) in the subject line. No other requests, instructions or other inquiries should be included with your e-mail requesting material. Metacrine, Inc. Meeting Information Meeting Materials: Notice of Meeting, Proxy Statement and Annual Report on Form 10-K Meeting Type: Annual Meeting of Stockholders Date: Monday, May 24, 2021 Time: 08:00 AM, Pacific Time Place: Annual Meeting to be held live via the Internet - please visit www.proxydocs.com/MTCR for more details. You must pre-register to attend the meeting online and/or participate at the email address indicated. SEE REVERSE FOR FULL AGENDA Copyright © 2021 Mediant Communications Inc. All Rights Reserved

Metacrine, Inc. Annual Meeting of Stockholders THE BOARD OF DIRECTORS RECOMMENDS A VOTE FOR PROPOSALS 1, 2 and 3. PROPOSAL 1. To elect the three nominees for director to serve as Class I directors for a three-year term to expire at the 2024 annual meeting of stockholders. 1.01 Preston Klassen, M.D. 1.02 Jeffrey Jonker 1.03 John McHutchison, M.D. 2. To ratify the appointment of Julia Owens, Ph.D. to our Board of Directors, on an advisory basis, to fill a vacancy in Class III, to hold office until the 2023 annual meeting of stockholders. 3. To ratify the selection by the Audit Committee of the Board of Directors of Ernst & Young LLP as our independent registered public accounting firm for our fiscal year ending December 31, 2021.