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                          December 7, 2023

       Anirvan Ghosh, Ph.D.
       Chief Executive Officer
       Unity Biotechnology, Inc.
       285 East Grand Avenue
       South San Francisco, CA 94080

                                                        Re: Unity 
Biotechnology, Inc.
                                                            Registration 
Statement on Form S-3
                                                            Filed December 6, 
2023
                                                            File No. 333-275924

       Dear Anirvan Ghosh:

              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 Joshua 
Gorsky at 202-551-7836 with any questions.



                                                                                
                          Sincerely,

                                                                                
                          Division of Corporation Finance
                                                                                
                          Office of Life Sciences
       cc:                                              Rick A. Werner, Esq.