United States securities and exchange commission logo

                            January 4, 2021

       Steven D. Harr, M.D.
       President and Chief Executive Officer
       Sana Biotechnology, Inc.
       188 East Blaine Street, Suite 400
       Seattle, Washington 98102

                                                        Re: Sana Biotechnology,
                                                            Amendment No. 1 to
Draft Registration Statement on Form S-1
                                                            Submitted December
18, 2020
                                                            CIK No. 0001770121

       Dear Dr. Harr:

             We have reviewed your amended registration statement and have the
       comments. In some of our comments, we may ask you to provide us with
information so we
       may better understand your disclosure.

              Please respond to this letter by amending your registration
statement and providing the
       requested information. If you do not believe our comments apply to your
facts and
       circumstances or do not believe an amendment is appropriate, please tell
us why in your

              After reviewing any amendment to your registration statement and
the information you
       provide in response to these comments, we may have additional comments.
Unless we note
       otherwise, our references to prior comments are to comments in our
December 7, 2020 letter.

       Amendment No. 1 to Draft Registration Statement on Form S-1

       Our in vivo Cell Engineering Platform and Programs, page 4

   1.                                                   We note your revisions
in response to prior comment 5. Please revise your statement that
                                                        you believe success
with any initial therapy targeting a given cell type may meaningfully
                                                        accelerate lead
candidate selection for other indications to remove any implication
                                                        that you will be able
to accelerate the development of your product candidates.
       Use of Proceeds, page 92

   2.                                                   We note your revisions
in response to prior comment 11. Based on the next anticipated
                                                        milestone for each of
your product candidates as described in the S-1, please revise this
                                                        section to disclose
which of those milestones you intend to complete using the proceeds of
 Steven D. Harr, M.D.
Sana Biotechnology, Inc.
January 4, 2021
Page 2
      this offering.
Allogeneic T Cell Program (SC291, SC255), page 163

3.    We note your revisions in response to prior comment 14. Please revise
your statement
      that your two programs "should increase the likelihood of success" to
remove any
      predictions or expectations regarding your likelihood of success as such
statements are
       You may contact Tracie Mariner at (202) 551-3744 or Mary Mast at (202)
551-3613 if
you have questions regarding comments on the financial statements and related
matters. Please
contact Ada D. Sarmento at (202) 551-3798 or Mary Beth Breslin at (202)
551-3625 with any
other questions.

FirstName LastNameSteven D. Harr, M.D.
                                                           Division of
Corporation Finance
Comapany NameSana Biotechnology, Inc.
                                                           Office of Life
January 4, 2021 Page 2
cc:       Brian J. Cuneo, Esq.
FirstName LastName