STRICTLY CONFIDENTIAL Aeterna Zentaris Inc. Summerville, South Carolina USA 29486 Attn: Klaus Paulini, Chief Executive Officer Dear Mr. Paulini:

Exhibit 10.3

Execution Version

July 1, 2020

STRICTLY CONFIDENTIAL

Aeterna Zentaris Inc.

000 Xxxxx Xxxxx, Xxxxx 000X

Xxxxxxxxxxx, Xxxxx Xxxxxxxx

XXX 00000

Attn: Xxxxx Xxxxxxx, Chief Executive Officer

Dear Xx. Xxxxxxx:

Reference is made to the engagement letter (the “Engagement Letter”), dated as of June 10, 2020, by and between Aeterna Zentaris Inc. (the “Company”) and X.X. Xxxxxxxxxx & Co., LLC (“Xxxxxxxxxx”), pursuant to which Xxxxxxxxxx shall serve, among other things, as the exclusive agent in any Offering of Securities of the Company during the “Term” (as defined in the Engagement Letter). Defined terms used herein but not defined herein shall have the meanings given to such terms in the Engagement Letter.

	(1)	The Company and Xxxxxxxxxx hereby agree to reduce the cash fee of Xxxxxxxxxx included in Section A.1 of the Engagement Letter to 7.0%, solely in connection with the Company’s Offering of its equity securities pursuant to the Registration Statement on Form F-1, as amended (File No. 333-239264).
	(2)	The Company and Xxxxxxxxxx hereby agree to reduce the amount of its expenses in case of a public offering included in clauses (b) and (c) of Section A.3 of the Engagement Letter to $15,000 and $90,000, respectively, solely in connection with the Company’s Offering of its equity securities pursuant to the Registration Statement on Form F-1, as amended (File No. 333-239264).
	(3)	The Company and Xxxxxxxxxx hereby agree to add the following to the end of the first sentence of Section A.5 of the Engagement Letter:

“; provided however that this section A.5 shall not apply solely in connection with the Company’s Offering of its equity securities pursuant to the Registration Statement on Form F-1, as amended (File No. 333-239264).”

(4) The Company and Xxxxxxxxxx hereby agree to amend and restate the first sentence of Section B of the Engagement Letter, as follows:

000 Xxxx Xxxxxx x Xxx Xxxx, Xxx Xxxx 00000 | 212.356.0500 | xxx.xxxxx.xxx

Member: FINRA/SIPC

“B. Term and Termination of Engagement; Exclusivity. The term of Xxxxxxxxxx’x exclusive engagement will begin on the date hereof and end twelve (12) months following the the consumatin of the Company’s Offering of its equity securities pursuant to the Registration Statement on Form F-1, as amended (File No. 333-239264) (the “Term”).

Except as expressly set forth above, all of the terms and conditions of the Engagement Letter shall continue in full force and effect after the execution of this agreement and shall not be in any way changed, modified or superseded by the terms set forth herein.

This agreement may be executed in two or more counterparts and by facsimile or “.pdf” signature or otherwise, and each of such counterparts shall be deemed an original and all of such counterparts together shall constitute one and the same agreement.

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IN WITNESS WHEREOF, this agreement is executed as of the date first set forth above.

	Very truly yours,
	X.X. XXXXXXXXXX & CO., LLC
	By:	/s/ Xxxxxx X. Xxxxxxx
	Name:	Xxxxxx X. Xxxxxxx
	Title:	Chief Operating Officer

Accepted and Agreed:
Aeterna Zentaris Inc.
By:	/s/ Xxxxx Xxxxxxx
Name:	Xxxxx Xxxxxxx
Title:	President and Chief Executive Officer

[AEZS EA Amendment Signature Page]

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