Keymed Biosciences Inc. announced that topline data from the registrational phase III clinical trial of its Class 1 new drug CM310 (generic name: Stapokibart) recombinant humanized monoclonal antibody injection for the treatment of moderate-to-severe atopic dermatitis (AD) (Protocol ID: CM310AD005) was released as a poster presentation at the European Academy of Dermatology and Venereology (EADV) Congress 2023. CM310AD005 is a multi-center, randomized, double-blind, placebo-controlled registrational phase III clinical trial, mainly used to evaluate the efficacy, safety, PK characteristics, PD effect, and immunogenicity of CM310 in subjects with moderate-to-severe atopic dermatitis. A total of 500 eligible patients were randomized 1:1 to receive CM310 (600mg ­ 300mg) or placebo every two weeks (Q2W).

The proportion of subjects achieving at least a 75% improvement of Eczema Area and Severity Index from baseline (EASI-75) and an Investigator's Global Assessment (IGA) score of 0/1 with a reduction of 2 points from baseline at week 16 are co-primary endpoints. In this clinical trial, the baseline EASI scores of the CM310 and the placebo groups were 24.84 and 24.05, respectively. The proportions of subjects with baseline IGA scores of 3 in the CM310 and the placebo groups were 52.2% and 52.6%, respectively.

The proportions of subjects with baseline IGA scores of 4 points in the CM310 and the placebo groups were 47.8% and 47.4%, respectively. Efficacy results showed co-primary endpoints were met at week 16 in this trial. At week 16, the proportion of subjects achieving EASI-75 was 66.9%, and the proportion of subjects achieving an IGA score of 0 or 1 point with a reduction of greater than or equal to 2 points from baseline (IGA 0/1, i.e. completely or substantially cleared skin lesions) was 44.2% in the CM310 group, outperforming placebo (25.8% and 16.1%, respectively), both of which were statistically significant differences (P<0.0001).

Significant improvements in both pruritus control and quality of life were observed from baseline to week 16. In the CM310 group, 35.9% of subjects achieved a 4 point improvement from baseline in the Peak Pruritus Numerical Rating Scale (PP-NRS) at week 16. In addition, the Dermatology Life Quality Index (DLQI) showed an improvement of 8.7 points from baseline at week 16.

Both the PP-NRS and DLQI in the CM310 group outperformed the placebo group (11.7% and 4.4 points, respectively) and were statistically significant (P<0.0001). In terms of safety, this trial demonstrated a favorable safety profile for CM310. The incidence of treatment-emergent adverse events (TEAEs) in the CM310 group was comparable to that in the placebo group, with most TEAEs being of mild to moderate in severity.