Connect Biopharma Holdings Limited (Nasdaq: CNTB) announced topline results from a global Phase 2 study evaluating rademikibart, a next-generation antibody targeting interleukin-4 receptor alpha (IL-4Rα). The study, named Seabreeze STAT Asthma (CBP-201-206), assessed the safety and efficacy of rademikibart as an add-on treatment for acute exacerbations in adult and adolescent participants with asthma and type 2 inflammation.
The study enrolled 160 patients who were randomized 1:1 to receive either a 600mg subcutaneous dose of rademikibart (n=79) or placebo (n=81). The primary endpoint was treatment failure, defined as death, hospital readmission, emergency department visits, or unscheduled medical visits for worsening symptoms within 28 days. The key secondary endpoint was the absolute change from baseline in post-bronchodilator forced expiratory volume in one second (FEV1) at Week 1.
Key topline results included a statistically significant improvement in lung function, with rademikibart showing an increase in post-bronchodilator FEV1 of 250 mL on Day 7 compared to 120 mL with placebo (130 mL greater improvement; p=0.023). The treatment also reduced the rate of treatment failure by approximately 66% over 28 days, though this endpoint did not reach statistical significance due to an overall lower treatment failure rate than projected. Additionally, the study observed a 50% reduction in emergency department visits or unscheduled medical visits for worsening asthma symptoms compared to placebo.
Safety data indicated that rademikibart was well tolerated with a low incidence of adverse events. The safety profile was comparable to placebo, with no individual adverse event occurring in more than two participants and no adverse events leading to study discontinuation in either arm. One serious adverse event was reported in the rademikibart arm compared to three in the placebo arm.
Connect Biopharma stated that it expects to report topline data from the ongoing Phase 2 Seabreeze STAT COPD study (CBP-201-207) later this month. Following the data release, the company plans to engage with the U.S. Food and Drug Administration (FDA) to gain alignment on a Phase 3 program.
