United States securities and exchange commission logo





                               July 16, 2020

       Douglas Love, Esq.
       President and Chief Executive Officer
       Annexon, Inc.
       180 Kimball Way, Suite 200
       South San Francisco, CA 94080

                                                        Re: Annexon, Inc.
                                                            Registration
Statement on Form S-1
                                                            Filed July 2, 2020
                                                            File No. 333-239647

       Dear Mr. Love:

              We have reviewed your registration statement and have the
following 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
       response.

              After reviewing any amendment to your registration statement and
the information you
       provide in response to these comments, we may have additional comments.

       Registration Statement on Form S-1 filed July 2, 2020

       Business, page 104

   1.                                                   We note your disclosure
on page 104 states that you "observed that early decline in NfL
                                                        significantly
correlated with improvement in the GBS-DS at the end of the study." We
                                                        also note that the
correlation coefficient included in the graph on pg. 104 is equal to 0.431.
                                                        Please revise your
description of the correlation coefficient to explain how the value
                                                        obtained places it in
the range of no correlation to perfect correlation and how you
                                                        determined the
variables were significantly correlated.
 Douglas Love, Esq.
FirstName  LastNameDouglas Love, Esq.
Annexon, Inc.
Comapany
July       NameAnnexon, Inc.
     16, 2020
July 16,
Page  2 2020 Page 2
FirstName LastName
Form S-1 filed July 2, 2020

Management's Discussion and Analysis
Critical Accounting Policies and Estimates
Stock Compensation, page 88

2.       You issued 71,719,859 shares of Series D redeemable convertible
preferred stock in June
         2020 at $1.4222 per share. In light of your valuation of your common
stock during June
         2020 and your anticipated IPO price, please tell us your consideration
of recording a
         beneficial conversion feature in the second quarter 2020 pursuant to
ASC 470-20, and if
         material, confirm you will disclose in the filing, prior to going
effective, the anticipated
         beneficial conversion feature that will be recorded. Please consider
discussing in your
         response any preferences related to the preferred shares that may
affect the determination
         of any beneficial conversion feature and how you considered those
preferences in your
         evaluation.
        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.

       Refer to Rules 460 and 461 regarding requests for acceleration. Please
allow adequate
time for us to review any amendment prior to the requested effective date of
the registration
statement.

        You may contact Mary Mast at (202) 551-3613 or Angela Connell,
Accounting Branch
Chief, at (202) 551-3426 if you have questions regarding comments on the
financial statements
and related matters. Please contact Deanna Virginio at (202) 551-4530 or Joseph
McCann at
(202) 551- 6262 with any other questions.



                                                               Sincerely,

                                                               Division of
Corporation Finance
                                                               Office of Life
Sciences
cc:      Brian J. Cuneo - Latham & Watkins LLP