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                              February 29, 2024

       Mark Lappe
       Chief Executive Officer
       Inhibrx Biosciences, Inc.
       11025 N. Torrey Pines Road, Suite 140
       La Jolla, CA 92037

                                                        Re: Inhibrx 
Biosciences, Inc.
                                                            Draft Registration 
Statement on Form 10
                                                            Submitted on 
January 29, 2024
                                                            CIK No. 0002007919

       Dear Mark Lappe:

                                                        We have reviewed your 
draft registration statement and have the following comments.

              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 a comment applies 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 this 
letter and your amended
       draft registration statement or filed registration statement, we may 
have additional comments.

       Draft Registration Statement on Form 10

       What conditions must be satisfied to complete the Spin-Off?, page xi

   1.                                                   Please clarify which 
conditions are waivable. For example, it appears that you would be
                                                        unable to waive the 
condition that there is    no legal restraint against the Separation,
                                                        Distribution, or the 
Merger.    If you believe you are able to waive this condition, please
                                                        explain how you proceed 
if there are legal restraints.
       Information Statement Summary
       Overview, page 1

   2.                                                   We note your disclosure 
that INBRX-109 is in a potentially registration-enabling trial in
                                                        Chondrosarcoma. Please 
define the term "registration-enabling" and explain why this
                                                        study is "potentially" 
registrational-enabling. Your discussion should clarify the factors
                                                        that will determine 
whether it is registrational and who will make such determination. In
                                                        addition, please 
provide balancing disclosure, as you do on page 14, that there can be no
 Mark Lappe
FirstName  LastNameMark
Inhibrx Biosciences, Inc. Lappe
Comapany29,
February   NameInhibrx
             2024        Biosciences, Inc.
February
Page 2 29, 2024 Page 2
FirstName LastName
         assurance that any of your clinical trials will ultimately be 
successful or support further
         clinical development, including development in registration-enabling 
trials of any of your
         therapeutic candidates.
3.       Please revise your information statement summary to briefly explain 
scientific or technical
         terms the first time they are used. By way of example only, we note 
the following terms:
             valent
             Agonist Function
4.       Please revise your graphics here, and elsewhere in the prospectus, to 
ensure that all text is
         legible.

5.       Please revise your pipeline table to more specifically describe the 
therapeutic indication(s)
         you are developing your candidates to treat.
Our Strategy, page 2

6.       With respect to your strategy to    rapidly advance and optimize the 
clinical development"
         of your lead programs." Please delete the the statement that you 
believe your programs
         have the potential to reach the marketplace as soon as 2026 with your 
first commercial
         therapeutic. Such a prediction is speculative and requires you to 
predict the outcome of
         your ongoing clincial trials, as well as the regulatory decisions and 
timing with respect to
         additional clincial trials and approval. Additionally, provide 
balancing disclosure
         indicating that that results of preclinical studies and early stage 
clinical trials of your
         therapeutic candidates may not be predictive of the results of later 
stage clinical trials,
         your initial intent to seek approval as a second or third-line 
therapy, your novel and
         unproven approach to protein engineering, and unforeseen 
circumstances, such as the
         partial clincial hold experienced in 2023, can lead to delays and 
additional expense.
Risk Factors
Risks Related to the Development, Clinical Testing and Commercialization of Our 
Therapeutic
Candidates, page 13

7.       Please include a separate, standalone risk factor disclosing that your 
approach to protein
         engineering is "novel and unproven, and as such, the cost, time needed 
to develop, and
         likelihood of success may be more uncertain" than if you employed more 
established drug
         development approaches.
Our therapeutic candidates may cause undesirable side effects that could delay 
or prevent their
marketing approval..., page 14

8.       We note your disclosure on page 15 that certain trial participants 
have in the past
         experienced serious adverse events that could be related to one of 
your therapeutic
         candidates. Please revise to describe all serious adverse events that 
occurred in your
         clinical trials and quantify the number of occurrences. With respect 
to the disclosures
 Mark Lappe
FirstName  LastNameMark
Inhibrx Biosciences, Inc. Lappe
Comapany29,
February   NameInhibrx
             2024        Biosciences, Inc.
February
Page 3 29, 2024 Page 3
FirstName LastName
         regarding the partial clinical hold and grade 5 hepatotoxicity event 
on pages 14 and 86,
         please define    grade 5    and confirm, if true, that this is a 
serious adverse event.
We are currently party to license agreements with Elpiscience and Transcenta 
for the
development..., page 18

9.       Please disclose, as you do on page 93, that the Transcenta Agreement 
includes
         development and, if approved, commercialization in China, Hong Kong, 
Macau and
         Taiwan for INBRX-109.
Business
Our Pipeline, page 81

10.      Please revise your disclosure on page 86 to clarify that the grade 5 
hepatotoxicity event
         was a seriouse adverse event. Additionally, with response to your 
disclosure that the
         adverse events related to Part 1 of your INBRX-106 trial being "mostly 
mild or moderate"
         and patients in the the Parts 3 and 4 of this trial having 
"predominently mild or moderate
         immune-related toxicities." Please clarify whether any of these 
adverse events were
         considered to be serious adverse events.


The 2020 2seventy Agreement, page 94

11.      With respect to the 2020 2seventy Agreement, please revise to clarify 
when the patent
         underlying the royalty term is expected to expire.
Unaudited Pro Forma Condensed Consolidated Financial Statements, page 129

12.      Please provide us an accounting analysis supporting your conclusion 
that carve out
         financial statements are not required for Inhibrx Biosciences Inc. 
that includes your
         valuation of the INBRX-101 Business, also referred to as RemainCo 
Business, compared
         to the SpinCo Business and consideration of the $2.2 billion 
transaction value for the sale
         of INBRX-101 to Sanofi as announced on January 23, 2024. In this 
regard, explain
         how the Chiesi Option Agreement is expected to impact your sale of the 
1INBRX-01
         Business to Sanofi. Refer us to the technical guidance upon which you 
relied. Also,
         provide the Exhibits and Schedules that appear to have been omitted 
from the Separation
         and Distribution Agreement in Form 8-K filed by Inhibrx Inc. on 
January 23, 2024.
Management's Discussion and Analysis of Financial Condition and Results of 
Operations, page
134

13.      You disclose on page 139 that you do not track your internal research 
and development
         expenses on a program-by-program basis as they primarily relate to 
personnel, early
         research and consumable costs, which are deployed across multiple 
projects under
         development. To the extent you track your external research and 
development expenses
 Mark Lappe
Inhibrx Biosciences, Inc.
February 29, 2024
Page 4
         on a program-by-program basis, revise to quantify the expenses on that 
basis. If you do
         not track your external costs, disclose that fact.
Notes to Consolidated Financial Statements
6. License and Grant Revenues, page F-21

14.      Please revise Note 6 or elsewhere in your footnotes as applicable to 
provide disclosure
         regarding your collaboration with Transcenta including to provide 
quantification ofthe
         terms governing the license agreement, the key assumptions and methods 
used to report
         activity under the agreements, and the associated impact on your 
financial statements.
         Refer us to the technical guidance upon which you relied.
       Please contact Franklin Wyman at 202-551-3660 or Kevin Vaughn at 
202-551-3494 if
you have questions regarding comments on the financial statements and related 
matters. Please
contact Jimmy (CF) McNamara at 202-551-7349 or Suzanne Hayes at 202-551-3675 
with any
other questions.



FirstName LastNameMark Lappe                                 Sincerely,
Comapany NameInhibrx Biosciences, Inc.
                                                             Division of 
Corporation Finance
February 29, 2024 Page 4                                     Office of Life 
Sciences
FirstName LastName