February 25, 2019

Leslie Auld
Chief Financial Officer
Aeterna Zentaris Inc.
315 Sigma Drive
Summerville, South Carolina 29486

       Re: Aeterna Zentaris Inc.
           Form 20-F for the Year Ended December 31, 2017
           Filed March 28, 2018
           Form 6-K for the Month of May 2018
           Filed May 7, 2018
           File No. 001-38064

Dear Ms. Auld:

        We have reviewed your January 18, 2019 response to our comment letter
and have the
following comment. In our comment, we may ask you to provide us with
information so we may
better understand your disclosure.

       Please respond to this comment within ten business days by providing the
requested
information or advise us as soon as possible when you will respond. If you do
not believe our
comment applies to your facts and circumstances, please tell us why in your
response.

       After reviewing your response to this comment, we may have additional
comments. Unless we note otherwise, our references to prior comments are to
comments in
our December 19, 2018 letter.

Form 6-K filed May 7, 2018

Exhibit 99.1
Notes to Condensed Interim Consolidated Financial Statements (unaudited)
4 Licensing Arrangements, page 10

1.    With regard to your response to comment one:
        as to the first bullet: you state it "makes sense" to allocate the $29
million, however,
         we continue to believe that the transaction price to be allocated on
day one is $24
         million as determined in accordance with paragraph 47 of IFRS 15.
Please advise
         with references to authoritative literature that supports your
conclusion.
        with regard to bullet two: tell us if another agreement will be
required for the license
 Leslie Auld
Aeterna Zentaris Inc.
February 25, 2019
Page 2
             of the Pediatric Indication and why or why not. We note that
Product is defined as
             "any pharmaceutical product containing the API including the
product developed by
             the Licensor for the Existing Indications" (plural). "Any
pharmaceutical product
             containing the API" seems quite broad. We further note that
Section 2.1(c) of the
             license agreement gives the Licensee the right and license to use
the Licensor IPR
             Package to Develop the Product for Commercialization. Develop is
defined as
             carrying out the PIP. The PIP is defined as the pediatric
investigation plan.
             Accordingly, it appears a license was granted for the Pediatric
Indication. Please
             direct us to the language in the license agreement that supports
your position. Explain
             why Section 2 of the license agreement does not use the term
"Adult Indication" is
             licensed as that term is defined in the agreement if that was the
only indication
             licensed.
             with regard to bullet four: you state "Strongbridge has no right
to access our Pediatric
             Indication IP". Please reconcile this to Section 2.1 of the
license agreement which
             states "grants to the Licensee the exclusive...right and license
to use the Licensor IPR
             Package".
             with regard to bullet five: our request for your basis in
determining the $400,000 was
             meant to elicit the authoritative literature which supports your
computation.
             in your financial statements for March 31, 2018 you indicated you
determined the
             license for Macrilen TM (macimorelin) for pediatric indication was
a "right to access"
             license. Please tell us why you changed your view on the type of
license entered into.


       You may contact SiSi Cheng at 202-551-5004 or Lisa Vanjoske at
202-551-3614 if you
have any questions.



FirstName LastNameLeslie Auld                                  Sincerely,
Comapany NameAeterna Zentaris Inc.
                                                               Division of
Corporation Finance
February 25, 2019 Page 2                                       Office of
Healthcare & Insurance
FirstName LastName