May 21, 2019 Jill C. Milne, Ph.D. President and Chief Executive Officer Catabasis Pharmaceuticals, Inc. One Kendall Square Bldg. 1400E, Suite B14202 Cambridge, MA 02139 Re: Catabasis Pharmaceuticals, Inc. Registration Statement on Form S-3 Filed May 14, 2019 File No. 333-231441 Dear Dr. Milne: 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 Christine Westbrook at 202-551-5019 with any questions. Sincerely, Division of Corporation Finance Office of Healthcare & Insurance cc: Rosemary G. Reilly, Esq.