United States securities and exchange commission logo October 4, 2023 Natalie Holles Chief Executive Officer Third Harmonic Bio, Inc. 1700 Montgomery Street, Suite 210 San Francisco, California 94111 Re: Third Harmonic Bio, Inc. Registration Statement on Form S-3 Filed October 2, 2023 File No. 333-274823 Dear Natalie Holles: This is to advise you that we have not reviewed and will not review your registration statement. Please refer to Rules 460 and 461 regarding requests for acceleration. We remind you that the company and its management are responsible for the accuracy and adequacy of their disclosures, notwithstanding any review, comments, action or absence of action by the staff. Please contact Tamika Sheppard at 202-551-8346 with any questions. Sincerely, Division of Corporation Finance Office of Life Sciences cc: Ryan Mitteness