United States securities and exchange commission logo





                             March 2, 2021

       Feng Tian
       Chairman, President and Chief Executive Officer
       Ambrx Biopharma Inc.
       10975 North Torrey Pines Road
       La Jolla, California 92037

                                                        Re: Ambrx Biopharma
Inc.
                                                            Draft Registration
Statement on Form F-1
                                                            Submitted February
3, 2021
                                                            CIK No. 0001836056

       Dear Dr. Tian:

              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 better
       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
       comments.

       Draft Registration Statement on Form F-1, Submitted February 3, 2021

       Summary
       Overview, page 1

   1.                                                   Please balance your
discussion in the Summary of the ongoing clinical trials related to
                                                        your product candidates
in China by clarifying that the clinical data discussed may not be
                                                        accepted by the FDA or
comparable foreign regulatory authorities, as you have stated in
                                                        the risk factor on page
32.
   2.                                                   Given your disclosures
regarding AEs and SAEs on pages 148-150, please balance your
                                                        statements concerning
your product candidates being well-tolerated or potentially safer
                                                        than other products in
the Summary.
 Feng Tian
FirstName  LastNameFeng Tian
Ambrx Biopharma   Inc.
Comapany
March      NameAmbrx Biopharma Inc.
       2, 2021
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FirstName LastName
3.       Please explain what you mean by "potentially registrational" trials,
as referenced
         throughout the prospectus.
Our Product Pipeline, page 2

4.       We note much of the trial disclosure is for studies conducted by
NovoCodex. Please revise
         the Summary and the description of the License Agreement with
NovoCodex for ARX788
         on pages 112 and 167 to explain your ability and intent to use and
rely upon NovoCodex   s
         trial data. Please also revise the pipeline table to clarify which
arrows reflect trials
         conducted by NovoCodex and in a footnote state the nature of your
relationship and
         ability to use such data.
5.       With respect to your pipeline table, please make the table and
footnotes legible and
         remove the    marketed    column from your pipeline table as it
implies likelihood of
         regulatory approval. Please also removed the planned trials from your
table.
6.       Please revise page 4 to define DCR.
7.       We note your statement on page 6 that in preclinical models, ARX788
has demonstrated
         greater anti-tumor activity as a single agent compared to T-DM1, an
approved ADC, in
         HER2-positive cancers. If this comparison reflects a head-to-head
comparison please
         revise to state such. If not, please remove such comparison as
comparisons to available
         products and other product candidates are not appropriate unless you
have conducted
         head-to-head trials.
ARX788, page 3

8.       We note your statement on page 4 that you have "developed a clinical
development
         strategy to accelerate the development of ARX788" and your emphasis
throughout the
         prospectus on "accelerated development timelines". We contrast these
statements with
         your risk factor on page 31 which states that accelerated approval by
the FDA, even if
         granted, may not lead to faster development or regulatory review or
approval. Please
         revise to balance your discussion in the Summary to clarify these
points.


Use of Proceeds, page 97

9.       Please revise this section to provide more specific detail regarding
the use of the funds to
         be allocated to the development and commercialization of ARX517 and
your EPB product
         candidates, including reference to specific phases of preclinical
and/or clinical trials, as
         applicable.
Business
Overview, page 130

10.      We note your statement on page 130 that you observed a favorable
safety profile in your
 Feng Tian
FirstName  LastNameFeng Tian
Ambrx Biopharma   Inc.
Comapany
March      NameAmbrx Biopharma Inc.
       2, 2021
March3 2, 2021 Page 3
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FirstName LastName
         ongoing Phase 1 clinical trial of ARX788. Please revise this statement
and all similar
         statements throughout your prospectus to remove implication that your
product candidates
         are safe or effective, as these determinations are solely within the
authority of the FDA
         and comparable regulatory bodies.
Our Product Pipeline, page 142

11.      Please provide the SAE details mentioned on page 27, including the one
death, in your
         description of the applicable study for ARX788 in the Business
section.
Summary of ARX788 Clinical Results, page 144

12.      Please revise page 146 and 148 to define EOT, SD and PR shown in the
graphics.
Our Collaborations, page 167

13.      Please revise page 169 to provide the royalty term of the License
Agreement with
         Agensys.
14.      On page 171 you state that the License Agreement with The Regents will
terminate upon
         the expiration of the last to expire patent or abandonment of the last
to be abandoned
         patent application licensed under the agreement. Please revise to
state when these patents
         are expected to expire, and also the royalty term.
15.      One page 172 you state that the License Agreement with Calibr
terminates upon the
         expiration of the last payment obligations under the agreement. Please
revise to state the
         payment obligations under the agreement, including any royalties or
milestone payments.
16.      With respect to the Elanco License Agreement, please revise page 172
to disclose the
         aggregate upfront and milestone payments received to date, the term
and termination
         provisions of the agreement, the aggregate potential milestone
payments to be received,
         and the royalty term. In addition, we note you have listed the Elanco
partnership in the
         collaboration pipeline table on page 140 but have not filed the
related License Agreement
         as an exhibit. Please either file the License Agreement pursuant to
Item 601(b)(10) of
         Regulation S-K, or provide an analysis as to why you do not believe
filing is required. If
         you do not consider the agreement material, please remove the
collaboration from the
         table.
Intellectual Property, page 176

17.      Please revise page 178 to state the material foreign jurisdictions
covered by your patents
         with respect to each of your EuCODE mammalian platform and the ReCODE
bacterial
         platform, respectively.
Description of American Depositary Shares
Governing Law, page 252

         We note on page 252 that your forum selection provision identifies
state and federal
 Feng Tian
FirstName  LastNameFeng Tian
Ambrx Biopharma   Inc.
Comapany
March      NameAmbrx Biopharma Inc.
       2, 2021
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FirstName LastName
18.      courts in New York, New York as the exclusive forum for certain
litigation. Please
         disclose whether this provision applies to actions arising under the
Securities Act or
         Exchange Act. If so, please also state that there is uncertainty as to
whether a court would
         enforce such provision. If the provision applies to Securities Act
claims, please also state
         that investors cannot waive compliance with the federal securities
laws and the rules and
         regulations thereunder. In that regard, we note that Section 22 of the
Securities Act creates
         concurrent jurisdiction for federal and state courts over all suits
brought to enforce any
         duty or liability created by the Securities Act or the rules and
regulations thereunder. If
         this provision does not apply to actions arising under the Securities
Act or Exchange Act,
         please also ensure that the exclusive forum provision in the governing
documents states
         this clearly, or tell us how you will inform investors in future
filings that the provision
         does not apply to any actions arising under the Securities Act or
Exchange Act.

         Please also revise your statement on page 82 where you refer to state
and federal courts in
         New York as having non-exclusive jurisdiction over matters arising
under the deposit
         agreement to clarify that such statement does not apply to suits by
investors, which must
         exclusively be filed in a state or federal court in New York, New
York.
Exhibits

19.      Please file the Shanghai Option Agreement as an exhibit pursuant to
Item
         601(b)(10)(i)(A) of Regulation S-K.

20.      On page 256 you state that the matters discussed in this section
related to US federal
         income tax law are the opinion of Cooley LLP, and the discussion of
Cayman Islands tax
         law are the opinion of Harney Westwood & Riegels; however, no tax
opinions have been
         filed as exhibits. Please file tax opinions in relation to the
opinions expressed on pages
         256-261, or advise. See Section III of Staff Legal Bulletin No. 19 for
guidance.
General

21.      Please supplementally 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.
       You may contact Michael Fay at 202-551-3812 or Brian Cascio at
202-551-3676 if you
have questions regarding comments on the financial statements and related
matters. Please
contact Margaret Schwartz at 202-551-7153 or Laura Crotty at 202-551-7614 with
any other
questions.



                                                               Sincerely,
 Feng Tian
Ambrx Biopharma Inc.
March 2, 2021
Page 5
FirstName LastNameFeng Tian
                                    Division of Corporation Finance
Comapany NameAmbrx Biopharma Inc.
                                    Office of Life Sciences
March 2, 2021 Page 5
cc:       Sean Clayton, Esq.
FirstName LastName