United States securities and exchange commission logo

                                 February 5, 2021

       Bronson Crouch
       Chief Executive Officer
       Instil Bio, Inc.
       3963 Maple Avenue, Suite 350
       Dallas, TX 75219

                                                        Re: Instil Bio, Inc.
                                                            Draft Registration
Statement on Form S-1
                                                            Submitted January
12, 2021
                                                            CIK 0001789769

       Dear Mr. Crouch:

              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

             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

       Our Pipeline, page 1

   1.                                                   Please revise your
pipeline chart to include separate columns for Phase 2 and Phase 3
                                                        trials or tell us the
basis for your belief that you will be able to conduct Phase 2/3 trials for
                                                        all your product
candidates. Please also shorten the ITIL-168 arrow for melanoma in the
                                                        pipeline chart to
reconcile with your disclosure elsewhere in the prospectus that you have
                                                        not yet submitted an
IND for this product candidate and revise the "Upcoming
                                                        Milestones" column of
your pipeline chart for ITIL-168 to reflect that your next milestone
                                                        will be the submission
of an IND, as discussed on page 5.
   2.                                                   We note your inclusion
of an undisclosed program at the bottom of your pipeline
                                                        chart. Given the status
of development and the limited disclosure on pages 5
 Bronson Crouch
FirstName    LastNameBronson Crouch
Instil Bio, Inc.
February      2021    Bio, Inc.
Page   2 5, 2021 Page 2
FirstName LastName
         and 120 regarding this program, it seems premature to highlight this
program prominently
         in your Summary pipeline table. Accordingly, please revise to remove
this program from
         the Summary table or advise.

Prospectus Summary
Overview, page 1

3.       We note your statement that you are a "clinical-stage"
biopharmaceutical company.
         However, your disclosure elsewhere indicates that you have not yet
submitted an IND or
         conducted a clinical trial. Please revise here and throughout your
document to remove
         your claim that you are "clinical-stage."
4.       Please revise your disclosure in the first paragraph here and in
Business to clarify, if true,
         that ITIL-168 was not administered in the compassionate use program.
5.       We note your disclosures in the Summary and throughout your document
claiming that
         you are "rapidly" advancing your product candidates and that you will
be able to
         "accelerate" the development and regulatory approval of ITL-168.
Please remove these
         statements or revise to provide appropriate context so that these
statements do not imply
         that you will be successful in developing and progressing your product
candidates in a
         rapid or accelerated manner.
6.       We note your use of the term    high unmet medical need    here and
elsewhere in the
         document. Such a term might imply that your products are eligible for
fast track
         designation or priority review granted by the FDA for products that
treat certain serious
         unmet medical needs. Please remove your use of this term throughout or
otherwise please
         explain why you believe use of this term is appropriate.
Our Strengths, page 2

7.       We note your discussion of the compassionate use program involving the
         of TIL products similar to ITIL-168 for the treatment of refractory
melanoma. Please
         revise your disclosure here and elsewhere in the document where the
results of the
         compassionate use program are described to clarify that the results
from this program do
         not provide a guarantee that ITIL-168 will be deemed to be safe or
effective for the
         treatment of melanoma or additional indications, and that extensive
clinical testing and
         regulatory approval will be required before ITIL-168 can be commonly
prescribed for the
         treatment of melanoma. In your revisions, please disclose how ORR, CR
and DCR were
         measured and the time periods used for the assessments. Please also
revise to disclose that
         10 of the 21 patients in the program died from complications arising
from disease
         progression, as indicated on page 114. In addition, please revise to
avoid characterizing
         the results of the program as "compelling" or "positive" as this may
create an inference
         that your product is more likely to be found safe and effective, which
is a determination
         solely in the authority of regulatory agencies such as the FDA.
 Bronson Crouch
FirstName    LastNameBronson Crouch
Instil Bio, Inc.
February      2021    Bio, Inc.
Page   3 5, 2021 Page 3
FirstName LastName
Our Product Candidates, page 4

8.       Please explain to us why you are using ITIL-168 for your planned Phase
2 clinical trial,
         rather than the TIL products that were administered in the
compassionate use program. In
         your explanation, please also tell us why it is appropriate to
summarize the results of the
         compassionate use program in your prospectus given that your
disclosure indicates that
         ITIL-168 was not administered pursuant to this program.
9.       We note your statement that you believe that your Phase 2 clinical
trial of ITIL-168 in
         melanoma could support a BLA submission. Please revise to briefly
discuss the basis for
         your belief that you will be able to submit a BLA for ITIL-168 without
conducting a
         Phase 3 clinical trial.
Implications of Being an Emerging Growth Company and a Smaller Reporting
Company, page 8

10.      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
Management   s Discussion and Analysis of Financial Condition and Results of
Common Stock Valuations, page 95

11.      Once you have an estimated offering price or range, please explain to
us how you
         determined the fair value of the common stock underlying your equity
issuances and the
         reasons for any differences between the recent valuations of your
common stock leading
         up to the initial public offering and the estimated offering price.
This information will
         help facilitate our review of your accounting for equity issuances
including stock
         compensation and beneficial conversion features. Please discuss with
the staff how to
         submit your response.
Our Pipeline, page 101

12.      We note your statement that CoStAR+ T cells demonstrated markedly
increased activity
         in preclinical studies. Please revise your disclosure to provide the
comparison basis for
         this statement.
Our TIL Manufacturing Process, page 108

13.      Please revise this subsection to discuss your reliance on sole source
vendors mentioned on
         page 38. To the extent you are substantially dependent on any
agreements with these
         parties, please identify them, describe the material terms of such
agreements and file the
         agreements as exhibit. If you believe you are not substantially
dependent on the
         agreements, please provide us with an analysis supporting your belief.
 Bronson Crouch
Instil Bio, Inc.
February 5, 2021
Page 4
14.    We note your statement that you are deploying a team to staff regional
processing hubs
       located near major treatment centers. Please revise to disclose how many
of these hubs are
       currently active and whether you own or lease these facilities.
Safety, page 114

15.    Please revise your description of the adverse events observed after TIL
infusion to
       disclose how many adverse events were linked to treatment and whether
there were any
       serious adverse events that were linked to treatment.
Intellectual Property, page 122

16.    Please revise to include the jurisdictions of your foreign patent
        You may contact Julie Sherman at 202-551-3640 or Vanessa Robertson at
3649 if you have questions regarding comments on the financial statements and
matters. Please contact Alan Campbell at 202-551-4224 or Celeste Murphy at
3257 with any other questions.

FirstName LastNameBronson Crouch
                                                              Division of
Corporation Finance
Comapany NameInstil Bio, Inc.
                                                              Office of Life
February 5, 2021 Page 4
cc:       Madison A. Jones
FirstName LastName