September 6, 2018

David Chang, M.D., Ph.D.
President and Chief Executive Officer
Allogene Therapeutics, Inc.
210 East Grand Avenue
South San Francisco, CA 94080

       Re: Allogene Therapeutics, Inc.
           Draft Registration Statement on Form S-1
           Submitted August 10, 2018
           CIK No. 0001737287

Dear Mr. Chang, M.D., Ph.D.:

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

       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 comments apply 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 these comments
and your
amended draft registration statement or filed registration statement, we may
have additional

Draft Registration Statement on Form S-1

Prospectus Summary
Overview, page 1

1.     We note your statements regarding the "unprecedented efficacy data" of
autologous cell
       therapies; that your platform "builds on the success of autologous
therapy"; and that you
       have a "deep pipeline" of product candidates targeting "multiple
validated . . . antigens."
        As currently drafted, these statements could imply that the FDA has
approved, or will
       more easily approve, your product candidates. Please revise throughout
the prospectus to
       remove any implication that your product candidates are more likely than
others to receive
 David Chang, M.D., Ph.D.
FirstName LastNameDavid Chang, M.D., Ph.D.
Allogene Therapeutics, Inc.
Comapany 6, 2018
September NameAllogene Therapeutics, Inc.
September 6, 2018 Page 2
Page 2
FirstName LastName
         FDA approval or explain to us why these statements are appropriate
given the stage of
         your product candidates.
Our Pipeline, page 2

2.       Please quantify and describe the most common adverse events you
reference in the
         carryover bullet point at the top of page 3 or include a
cross-reference to the discussion on
         page 97.
3.       Please either identify the "multiple undisclosed" programs or remove
them from the the
         pipeline table here and on pages 82 and 93. The table is intended to
provide information
         about your product candidates in development that are reasonably
likely to result in an
         approved product in the foreseeable future. Unless an indication and a
compound have
         been identified, the product is too preliminary for inclusion in the
4.       Please clarify what you mean by the "complete response" and "minimum
residual disease
         negative" in the carryover paragraph at the top of page 3.
5.       Please include columns for Phase 2 and Phase 3 in your product
pipeline table here and on
         pages 82 and 93.
Implications of Being an Emerging Growth Company, page 6

6.       Please provide us with copies of all written communications, as
defined in Rule 405 under
         the Securities Act, that you, or anyone authorized to do so on your
behalf, present to
         potential investors in reliance on Section 5(d) of the Securities Act,
whether or not they
         retain copies of the communications.
Use of Proceeds, page 58

7.       We note your disclosure that you intend to use net proceeds to fund
portion of the costs
         for the ongoing UCART19 CALM and PALL clinical trials; the planned
         CALM II and PALL II clinical trials; the planned clinical trial of
ALLO-501; and the
         planned clinical trial of ALLO-715. Please specify how far in the
development of each of
         the listed clinical trials you expect to reach with the proceeds of
the offering. If any
         material amounts of other funds are necessary to accomplish the
specified purposes, state
         the amounts and sources of other funds needed for each specified
purpose and the
         sources. Refer to Instruction 3 to Item 504 of Regulation S-K.
Certain Relationships and Related Party Transactions
Investor Agreements, page 156

8.       To the extent any of the amended and restated investor rights
agreements, amended and
         restated voting agreement, and amended and restated right of first
refusal and co-sale
         agreement will remain in effect after the initial public offering,
please describe their
         material terms and file them as exhibits to your registration
 David Chang, M.D., Ph.D.
Allogene Therapeutics, Inc.
September 6, 2018
Page 3

       You may contact Paul Cline at (202) 551-3851 or Mark Brunhofer at (202)
551-3638 if
you have questions regarding comments on the financial statements and related
matters. Please
contact Tonya K. Aldave at (202) 551-3601 or J. Nolan McWilliams at (202)
551-3217 with any
other questions.

FirstName LastNameDavid Chang, M.D., Ph.D.
                                                          Division of
Corporation Finance
Comapany NameAllogene Therapeutics, Inc.
                                                          Office of Healthcare
& Insurance
September 6, 2018 Page 3
cc:       Charles J. Bair, Esq.
FirstName LastName