Presentation of First-in-Human Trial Results for PAI-1 Inhibitor RS5441 at the 3rd BCN Hair Meeting

We are pleased to announce that Eirion Therapeutics, Inc. (Headquarters: Woburn, Massachusetts, U.S.A.; hereinafter “Eirion”), which is advancing the research and development of RS5441, a PAI-1 inhibitor created by the Company, for dermatological indications (androgenetic alopecia and age-related hair loss), will present the results of the First-in-Human trial of ET-02, its topical formulation of RS5441, at the 3rd BCN Hair Meeting, to be held in Sitges, Spain, from September 17 to 19, 2026.

Overview of the Presentation
Dr. Jon Edelson, CEO of Eirion, is scheduled to present the clinical trial results of topical 5% ET-02 during poster sessions on September 18 and 19, including a comparison with previously reported data for topical and oral minoxidil.

According to Eirion, the hair growth assessment results obtained after 28 days of ET-02 use were reported to show favorable results compared with previously reported data for topical minoxidil at the 4-month time point and oral minoxidil at the 6-month time point.

Eirion states that it plans to initiate a six-month Phase II clinical trial in 2027.

The Company’s Relationship with ET-02 (RS5441)
RS5441 is a PAI-1 inhibitor created by the Company. In October 2016, the Company granted Eirion an exclusive license for dermatological indications (androgenetic alopecia and age-related hair loss). The compound is being developed by Eirion as the topical formulation ET-02. The Company has previously disclosed the initiation of the Phase I clinical trial in a timely disclosure dated July 3, 2024, and the trial results in a timely disclosure dated January 9, 2025.

If ET-02 is commercialized by Eirion in the future, the Company expects to receive royalties from Eirion.

Outlook
If any developments regarding Eirion’s future development activities, including the initiation of a Phase II clinical trial, are expected to have a material impact on the Company’s financial results, the Company will make a separate announcement in accordance with applicable timely disclosure rules.