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                              March 30, 2022

       Keith Gottesdiener, M.D.
       President and Chief Executive Officer
       Prime Medicine, Inc.
       21 Erie Street
       Cambridge, MA 02139

                                                        Re: Prime Medicine,
Inc.
                                                            Amendment No. 4 to
Draft Registration Statement on Form S-1
                                                            Submitted March 25,
2022
                                                            CIK No. 0001894562

       Dear Dr. Gottesdiener:

            We have reviewed your amended draft registration statement and have
the following
       comment.

              Please respond to this letter by providing the requested
information and either submitting
       an amended draft registration statement or publicly filing your
registration statement on
       EDGAR. If you do not believe our comment applies to your facts and
circumstances or do not
       believe an amendment is appropriate, please tell us why in your
response.

             After reviewing the information you provide in response to this
comment and your
       amended draft registration statement or filed registration statement, we
may have additional
       comments.

       Amendment No. 4 to Draft Registration Statement on Form S-1

       Our Prime Editing Platform, page 1

   1.                                                   We note your response
to prior comment 1 and your position in your response that the
                                                        license agreement does
"not impose material limitations on the Company   s future use of
                                                        Prime Editing
technology." So that investors can better understand your business model
                                                        and intellectual
property rights arrangements, and can better evaluate the materiality of
                                                        this information,
please expand the disclosure in your summary section to indicate, if true,
                                                        that:
                                                            your license
agreement is with the Broad Institute (and provide a summary of the
                                                             Prime Broad
Field);
                                                            your license
agreement is subject to Broad Institute   s inclusive innovation model,
                                                             pursuant to which
Broad Institute retains the right, in certain circumstances, to grant
 Keith Gottesdiener, M.D.
Prime Medicine, Inc.
March 30, 2022
Page 2
           to third parties (other than specified competitors of yours)
licenses under the licensed
           patent rights that would otherwise fall within the scope of the
exclusive license
           granted to your company; and
             all gene targets, which are any human genes to which a program is
directed, are
           subject to Broad Institute's march-in license, which means Broad
Institute has the
           right to terminate your license to gene targets under certain
conditions and could
           make one or more gene targets unavailable to your company, but that
once you
           initiate a program for a gene target, in accordance with the terms
of the Broad
           License Agreement, Broad Institute loses the right to use its
march-in license for such
           gene target, provided you continue to use commercially reasonable
efforts to continue
           to progress such development and that, as such, you believe that
Broad Institute
           cannot exercise its march-in license with respect to any of your
current programs for
           gene targets because such programs have been initiated in accordance
with the terms
           and requirements of the Broad License Agreement and you believe the
march-in
           license would only potentially impact a small number of individual
gene targets, and
           the march-in license would likely not have an impact on the company
 s ability to
           initiate a program for a gene target, if desired.

       You may contact Tracey Houser at 202-551-3736 or Angela Connell at
202-551-3426 if
you have questions regarding comments on the financial statements and related
matters. Please
contact Dillon Hagius at 202-551-7967 or Tim Buchmiller at 202-551-3635 with
any other
questions.



                                                             Sincerely,
FirstName LastNameKeith Gottesdiener, M.D.
                                                             Division of
Corporation Finance
Comapany NamePrime Medicine, Inc.
                                                             Office of Life
Sciences
March 30, 2022 Page 2
cc:       Marishka DeToy, Esq.
FirstName LastName