Keymed Biosciences Announces Long-term Efficacy and Safety Data from a Phase III Clinical Trial of Stapokibart for the Treatment of Moderate-to-severe Atopic Dermatitis

CHENGDU, China, June 3, 2024 /PRNewswire/ -- Keymed Biosciences Inc. (HKEX: 02162) today announced the long-term efficacy and safety data of a Phase III clinical trial of stapokibart injection in patients with moderate-to-severe atopic dermatitis (AD) has been released by way of oral presentation at the European Academy of Allergy and Clinical Immunology (EAACI) Congress 2024. The data of long-term treatment with stapokibart demonstrated sustained efficacy and favorable safety profile in adult patients with moderate-to-severe AD, and no new safety signals were observed.

This multicenter, randomized, double-blind, placebo-controlled phase III trial was designed to assess the efficacy, safety, pharmacokinetics, pharmacodynamics, and immunogenicity of stapokibart in patients with moderate-to-severe AD. A total of 476 patients entered the maintenance treatment period, with 238 in each group. At week 52, EASI-75 was achieved in 92.5% of patients continuing stapokibart and 88.7% of those switching from placebo to stapokibart, IGA score of 0/1 with a ≥2-point reduction was achieved in 67.3% and 64.2%, respectively; a ≥4-point reduction in weekly average of daily PP-NRS was achieved in 67.3% and 60.5%, respectively. Long-term treatment with stapokibart continuously improved AD symptoms and quality of life of patients with moderate-to-severe AD. Only 1 patient (0.9%) relapsed during the maintenance period. In terms of safety, stapokibart was well-tolerated, and its safety profile over 52 weeks was consistent with the initial 16-week double-blind period, with no new safety signals identified.

During the double-blind treatment period, a total of 500 adult patients with moderate-to-severe AD were randomized 1:1 to receive stapokibart 300 mg (loading dose: 600 mg) or placebo every 2 weeks for 16 weeks. In the subsequent 36- week maintenance treatment period, patients in the stapokibart group continued the same dose, and patients switching from placebo to stapokibart received stapokibart 300 mg (loading dose: 600 mg) every 2 weeks. Concomitant use of topical medications for AD treatment was permitted during the maintenance treatment period. The co-primary endpoints of this trial were the proportions of patients achieving ≥75% improvement from baseline in Eczema Area and Severity Index score (EASI-75) and an Investigator's Global Assessment (IGA) score of 0/1 with a ≥2 point reduction from baseline at week 16. Other efficacy indicators included EASI score, IGA score, and Peak Pruritus Numerical Rating Scale (PP-NRS), etc.

About Stapokibart

Stapokibart (CM310) is a highly efficient, humanized antibody targeting the interleukin-4 receptor alpha subunit (IL-4Rα), and is the first domestically manufactured IL-4Rα antibody drug receiving clinical trial approval from the NMPA. By targeting IL-4Rα, Stapokibart can block both interleukin-4 (IL-4) and interleukin-13 (IL-13) signaling. IL-4 and IL-13 are two key cytokines that trigger type 2 inflammation. Stapokibart has shown a good safety profile and encouraging efficacy in a number of previous clinical trials, and its new drug application for the treatment of moderate-to-severe atopic dermatitis in adults was accepted by the NMPA and granted priority review on December 7, 2023.

About Keymed Biosciences Inc.

Keymed Biosciences Inc. (HKEX: 02162) focuses on the urgent unmet clinical needs, and is committed to providing high-quality, affordable, innovative therapies for patients in China and overseas. To accelerate the efficiency of our research and discovery, the Company has established a fully-integrated platform encompassing all of the key functions in the biological drug development which include target validation, lead molecule discovery and optimization, preclinical evaluation, process development, translational research, clinical development and manufacturing. This integrated platform has enabled us to rapidly and cost-effectively identify, build, expand and advance our diversified pipeline of innovative and differentiated antibody-based therapies, including monoclonal antibodies, antibody drug conjugates (ADCs) and bispecific antibodies.

For more information, please visit www.keymedbio.com.