Mr. Peter Puccetti reports

COSCIENS BIOPHARMA INC. ANNOUNCES LEADERSHIP CHANGE

Peter H. Puccetti, CFA, chairman of Cosciens Biopharma Inc.'s board of directors, has been appointed as interim chief executive officer, effective immediately. Mr. Puccetti succeeds Anna Biehn, who has stepped down as CEO.

"As the company continues its efforts to reduce costs and streamline its organizational structure while aligning resources with key strategic priorities, the board has determined that now is the right time to transition leadership," said Robert Seager, chair of the human resources, nominating and governance committee. "Peter is already deeply involved in driving the strategic reorientation of the company and has a proven track record of creating value with similarly situated businesses. We are confident that the company will be well served by Peter's leadership at this critical juncture."

Mr. Puccetti said, "In my expanded role as chairman and interim CEO, I plan on continuing to strengthen operational performance, while working to create the conditions necessary for driving shareholder value." Mr. Puccetti continued: "On behalf of everyone at Cosciens, I want to thank Anna for her professionalism, leadership and contributions. We wish her all the best in her future endeavors."

About Cosciens Biopharma Inc.

Cosciens is a life science company with a diverse portfolio focused on the development of natural, plant-based active ingredients and engaged in the commercialization of pharmaceutical and diagnostic products. Cosciens's natural active ingredient business leverages the company's proprietary manufacturing and extraction technologies to develop avenanthramides and beta glucan active ingredients currently used in leading skincare brands worldwide. Cosciens's lead pharmaceutical product, macimorelin (Macrilen; Ghryvelin), is the first and only U.S. Food and Drug Administration- (FDA) and European Medicines Agency- (EMA) approved oral test indicated for the diagnosis of adult growth hormone deficiency (AGHD).

The company's common shares are listed on the Toronto Stock Exchange under the symbol CSCI. The company's common shares were assigned the trading symbol CSCIF by FINRA's Department of Market Operations for quoting and trading in the market for unlisted securities (the over-the-counter (OTC) market) in the United States as of Sept. 4, 2025.

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