Shenlian Biotech (688098.SH): Phase II clinical trial of UB-221 to treat chronic spontaneous urticaria reached the main end

Zhitong Finance App News, Shenlian Biology (688098.SH) issued an announcement to evaluate the efficacy, safety, pharmacokinetics and pharmacokinetics of UB-221 as an additive therapy for chronic spontaneous urticaria (CSU) with a Class 1 biopharmaceutical UB-221 injection developed independently by the company Sun Company, Yangzhou Shizhiyuan Biotechnology Co., Ltd. (hereinafter referred to as “Shizhiyuan”). “Science” has reached a major end , and achieved positive top-line results.

Ub-221 is a subcutaneous injectable humanized monoclonal antibody drug targeting IgE. It is a next-generation product developed by Professor Zhang Ziwen, the inventor of anti-IgE therapy and omalizumab, to treat allergic diseases mediated by IgE. On the one hand, Ub-221 binds to IgE, neutralizes free IgE molecules in the blood, blocks its binding to mast cells and basophil surface receptors, and inhibits the release of inflammatory mediators such as histamine. On the other hand, CD23 (also known as FcrII) is a low-affinity IgE receptor on the surface of B cells. The binding of IgE to CD23 participates in negative regulatory feedback generated by IgE. Ub-221 does not affect the binding of IgE to the CD23 receptor on the B cell surface. This characteristic can reduce IgE synthesis to a certain extent, so UB-221 has a potential differentiating mechanism of action. Previously, the results of the phase I clinical trial of UB-221 to treat chronic spontaneous urticaria were published in the authoritative international journal “The Journal of Clinical Investigation”.

This phase II clinical trial is a multicenter, randomized, double-blind, placebo-controlled parallel study to evaluate the efficacy, safety, pharmacokinetics, and pharmacodynamics of UB-221 subcutaneous injection as an additive therapy in patients with chronic spontaneous urticaria (CSU). The study included 145 subjects with moderate to severe chronic spontaneous urticaria. The patients were randomly assigned to one of the five treatment groups according to a 2:2:2:1:1 ratio and received 4 mg/KGUB-221, 2 mg/KGUB-221, 1 mg/KGUB-221, and 300 mg omalizumab or placebo, respectively.

Research results showed that UB-221 injection showed positive efficacy and safety in patients with chronic spontaneous urticaria. In terms of efficacy, HSS7 = 0 (complete elimination of wind clusters) at week 12 of the main efficacy endpoint showed a dose-response relationship. The response rates for UB-221 4 mg/kg, 2 mg/kg, and 1 mg/kg groups were 54%, 53%, and 43%, respectively, significantly higher than 11% of the placebo group (p<0.005, <0.005, and <0.05, respectively), while the omalizumab 300 mg group was 41%. The end point of the key secondary efficacy was UAS7 = 0 (complete relief of itching) at week 12. The response rates for each dose group were 46%, 39%, and 38%, respectively. Among them, the 4 mg/kg group was statistically significant (p<0.05) compared to the placebo group, while the omalizumab 300 mg group was 29%.

The efficacy of UB-221 was further improved after week 12. Among them, the HSS7=0 response rate in the 4mg/kg group reached 69% in the 22nd week (i.e. 6 weeks after discontinuation) and remained at 60% in the 28th week (i.e. 12 weeks after discontinuation), while the omalizumab group was 24%, with a difference of 36 percentage points between the two groups, indicating that UB-221 overall had better and more long-lasting clinical benefits, and supported its potential differential effects.

In terms of safety, UB-221 was generally well tolerated. Adverse events related to treatment occurred similarly in each treatment group. There were no serious treatment-related adverse events or hypersensitivity reactions including anaphylactic shock, and the incidence of reactions at the injection site was low and did not lead to discontinuation of the drug. Based on the results of the Phase II study, UB-221 showed a clear dose-response relationship and sustained efficacy in complete remission of the disease, supporting subsequent phase III clinical studies on chronic spontaneous urticaria.