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                          May 11, 2023

       Martin Mackay, Ph.D.
       Chief Executive Officer
       Rallybio Corp
       234 Church Street, Suite 1020
       New Haven, CT 06510

                                                        Re: Rallybio Corp
                                                            Registration 
Statement on Form S-3
                                                            Filed May 9, 2023
                                                            File No. 333-271748

       Dear Martin Mackay:

              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 Jason 
Drory at 202-551-8342 with any questions.



                                                                                
                          Sincerely,

                                                                                
                          Division of Corporation Finance
                                                                                
                          Office of Life Sciences
       cc:                                              Zach Blume