Seikagaku Announces an Application for Marketing Approval of SI-449, an Adhesion Barrier, as a Medical Device in Japan

August 20, 2025 SEIKAGAKU CORPORATION

(Securities Code: TSE 4548)

Seikagaku Corporation (Tokyo, Japan; "Seikagaku") announced that it has submitted in Japan an application for marketing approval as a medical device for SI-449 (hereafter “the Product”), which has been developed as a surgical adhesion barrier.

The application for approval is based on the results of clinical studies conducted in Japan.

Seikagaku engages in the research and development of new products, focusing on the field of glycoscience. With the Product, Seikagaku aims to reduce the risk of complications arising from post-operative adhesion formation1 and contribute to a healthy and fulfilling quality of life for patients.

There is no change in the forecast of consolidated financial results for the fiscal year ending March 31, 2026 in connection with this matter.

SI-449 is a powdered adhesion barrier whose main ingredient is cross-linked chondroitin sulfate developed using Seikagaku’s own glycosaminoglycan2 cross-linking technology. SI-449 consists of substances naturally present in the body, including the cross-linking agent, and is thought to be highly biocompatible. SI-449, which has the property of absorbing moisture and swelling, is expected to prevent or mitigate post-operative adhesion formation2 by forming a barrier between the surgical wound site and surrounding tissues after application. Since SI-449 is a powdered formulation, it adheres well to uneven tissue surfaces, and is also thought to offer excellent usability in laparoscopic surgery, a common surgical procedure.

*1 Post-operative adhesion formation is a phenomenon by which a surgical wound site and surrounding tissues that are normally separated adhere together in the healing process of sites where tissue loss or damage has occurred in surgery (open abdominal surgery, laparoscopic surgery, etc.). The incidence of post-operative adhesions is 50% to 90% when no treatment is performed, and adhesions are a major cause of postsurgical complications (intestinal blockage, chronic abdominal pain, infertility, etc.) in abdominal or gynecological surgery. Sheet or gel products are currently the main products used as adhesion barriers.

*2 Glycosaminoglycans (GAGs) are a major component of glycoconjugates. Chondroitin sulfate and hyaluronic acid are GAGs.

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Note: This document has been translated from the Japanese original for reference purposes only. In the event of any discrepancy between this translated document and the Japanese original, the original shall prevail.