United States securities and exchange commission logo

                               August 18, 2020

       Marcio Souza
       Chief Executive Officer
       Praxis Precision Medicines, Inc.
       One Broadway, 16th Floor
       Cambridge, MA 02142

                                                        Re: Praxis Precision
Medicines, Inc.
                                                            Draft Registration
Statement on Form S-1
                                                            Submitted July 22,
                                                            CIK No. 0001689548

       Dear Mr. Souza:

              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 on Form S-1

       Prospectus Summary
       Company Overview, page 1

   1.                                                   We note your statements
indicating that your therapeutics are potentially "best-in-class" or
                                                        "first-in-class." These
terms suggest that your product candidates are effective, likely to be
                                                        approved and favorable,
as compared to competitive products and product candidates.
                                                        Given the status of
development, it is premature for you to make such statements or
                                                        implications at this
time. Accordingly, please delete all references in your registration
                                                        statement to your
product candidates being potentially "best-in-class" or "first-in-class." If
                                                        your use of these terms
was intended to convey your belief that the products are based on
                                                        a novel technology or
approach and/or is further along in the development process, you
 Marcio Souza
FirstName  LastNameMarcio    Souza
Praxis Precision Medicines, Inc.
August  18, NamePraxis
            2020       Precision Medicines, Inc.
Page 2 18, 2020 Page 2
FirstName LastName
         may discuss how your technology differs from technology used by
competitors and, if
         applicable, that you are not aware of competing products that are
further along in the
         development process. Statements such as these should be accompanied by
         language that the statements are not intended to give any indication
that the product
         candidates have been proven effective or that they will receive
regulatory approval.
2.       Please revise your statement that you own global commercialization
rights for all of your
         product candidates with reference to your financial obligations under
your license and
         collaboration agreements as discussed on pages 154-156.
3.       We note your disclosure that you intend to initiate the first of two
registrational trials,
         Phase 2/3, in the United States and Australia. Your characterization
of two trials as
         registrational is not appropriate given that you must complete
multiple trials prior to
         submitting the related New Drug Application (NDA). Please revise your
disclosure to
         remove this characterization here and throughout your prospectus.
PRAX-114, page 2

4.       We note your disclosure that you have an ongoing three-part Phase 2a
clinical trial
         ongoing in Australia, with Part A having demonstrated rapid and marked
improvements in
         depression scores in MDD patients. As efficacy determinations are
solely within the
         authority of the U.S. Food and Drug Administration (FDA) and
comparable regulatory
         bodies, it is inappropriate to state or imply that your product
candidates are effective.
         Please revise this statement and similar statements here and
throughout your prospectus,
         including, but not limited to, in your Business section. We will not
object to a discussion
         of objective data resulting from your trials without including
conclusions related to
         efficacy. As a non-exhaustive list of illustrative examples only, we
note the following
             To date, PRAX-562 has demonstrated efficacy in in vivo models...
             Based on clinical data showing a rapid, pronounced and durable
antidepressant effect
              in MDD patients...
             We plan to initiate a Phase 2 trial for Short-lasting Unilateral
Neuralgiform headache
              with Conjunctival injection and Tearing, or SUNCT, and
              Unilateral Neuralgiform headache attacks with Autonomic symptoms,
or SUNA, to
              demonstrate rapid clinical proof-of-concept and then subsequently
expand into severe
              pediatric epilepsies.
             Because the doses at which EEG changes observed in rats are
similar to those that
              demonstrated efficacy in a preclinical model of essential
             We have evaluated the safety and tolerability of PRAX-944 in over
100 healthy
              volunteers in four separate clinical trials and demonstrated
pharmacodynamic effects
              in humans using EEG.
 Marcio Souza
FirstName  LastNameMarcio    Souza
Praxis Precision Medicines, Inc.
August  18, NamePraxis
            2020       Precision Medicines, Inc.
Page 3 18, 2020 Page 3
FirstName LastName
Our Strategy, page 4

5.       We note that you state your strategy is to "efficiently advance" your
product candidates
         towards regulatory approval and commercialization. Please revise your
disclosure to
         remove any implication that you may be able to accelerate the FDA
review process.
Risks Associated with Our Business, page 5

6.       Please expand your disclosure in the fourth bulletpoint to highlight
the risk that your
         clinical trials to date have been conducted outside the U.S. and that
if the FDA or
         comparable regulators do not accept earlier preclinical and clinical
data you may need to
         conduct additional clinical trials, as referenced on pages 16 and 24.
Please also add a
         bullet point highlighting the risks related to concentration of
ownership of your common
         stock, as referenced on page 73.
Use of Proceeds, page 82

7.       It appears from your disclosure that the proceeds from the offering
will not be sufficient to
         fund development of your product candidates through regulatory
approval and
         commercialization. Please disclose the sources of other funds needed
to reach regulatory
         approval and commercialization for each product candidate. Refer to
Instruction 3 to Item
         504 of Regulation S-K.
Our Approach, page 116

8.       Please expand your disclosure to explain briefly what you mean by
"validated" target-
         specific EEG endpoints. Additionally, please define "CHO cells" used
on page 122.
Broad Psychiatry and Neurology Programs
Phase 2a trial in patients with depression
Part A results, page 127

9.       We note your comparison of the results of PRAX-114 observed in your
Phase 2a Part A
         trial to published reports on changes in HAM-D scale in clinical
trials of approved
         antidepressants. As these comparisons are not based on head-to-head
studies, please tell us
         why you believe it is appropriate to include them. Address in your
response whether you
         expect to be able to rely on such comparisons to support an
application for marketing
 Marcio Souza
Praxis Precision Medicines, Inc.
August 18, 2020
Page 4
License Agreement with RogCon, page 154

10.   We note your disclosure that the $3.0 million milestone payment will
become due to
      RogCon when the first profit share payment has become due and certain
      contingent payments become due to Ionis. Please expand your disclosure to
specify the
      triggers for these payments.
Ionis Collaboration Agreement, page 155

11.   Please expand your disclosure to include the financial terms related to
the option exercise
      provisions, including the royalty rate or range not to exceed ten
percentage points.
License Agreement with Purdue, page 155

12.   Please expand your disclosure to include the period of time relevant to
the royalty term.

13.   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 Gary Newberry at 202-551-3761 or Kate Tillan at
202-551-3604 if you
have questions regarding comments on the financial statements and related
matters. Please
contact Courtney Lindsay at 202-551-7237 or Christine Westbrook at 202-551-5019
with any
other questions.

FirstName LastNameMarcio Souza
                                                            Division of
Corporation Finance
Comapany NamePraxis Precision Medicines, Inc.
                                                            Office of Life
August 18, 2020 Page 4
cc:       William D. Collins, Esq.
FirstName LastName