October 8, 2019

Martin Babler
President and Chief Executive Officer
Principia Biopharma Inc.
220 East Grand Avenue
South San Francisco, California 94080

       Re: Principia Biopharma Inc.
           Registration Statement on Form S-3
           Filed October 1, 2019
           File No. 333-234038

Dear Mr. Babler:

        We have limited our review of your registration statement to the issue
we have addressed
in our comment.

       Please respond to this letter by amending your registration statement
and providing the
requested information. 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 any amendment to your registration statement and the
information you
provide in response to this comment, we may have additional comments.

Registration Statement on Form S-3 filed October 1, 2019

Description of Capital Stock
Choice of Forum, page 16

1.     We note that your forum selection provision identifies the Court of
Chancery of the State
       of Delaware as the exclusive forum for certain litigation, including any
"derivative
       action." Please disclose whether this provision applies to actions
arising under
       the Exchange Act. In that regard, we note that Section 27 of the
Exchange Act creates
       exclusive federal jurisdiction over all suits brought to enforce any
duty or liability created
       by the Exchange Act or the rules and regulations thereunder. If this
provision does not
       apply to actions arising under the Exchange Act, please tell us how you
will inform
       investors in future filings that the provision does not apply to any
actions arising under
       the Exchange Act.
 Martin Babler
Principia Biopharma Inc.
October 8, 2019
Page 2

        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.

       Please contact Irene Paik at 202-551-6553 or Christine Westbrook at
202-551-5019 with
any questions.



                                                           Sincerely,
FirstName LastNameMartin Babler
                                                           Division of
Corporation Finance
Comapany NamePrincipia Biopharma Inc.
                                                           Office of Life
Sciences
October 8, 2019 Page 2
cc:       Amanda Busch - Cooley LLP
FirstName LastName