Upstream Bio VALIANT Trial Shows Verekitug Significantly Reduces Asthma Exacerbation Rate

Upstream Bio announced positive top-line results from the Phase 2 VALIANT clinical trial evaluating the safety and efficacy of verekitug in adults with severe asthma. Verekitug is the only known clinical-stage antagonist targeting the receptor for thymic stromal lymphopoietin, or TSLP. VALIANT met the study's primary endpoint of a statistically significant and clinically meaningful reduction in the annualized asthma exacerbation rate, or AAER, with both every 12 week and every 24 week dosing, with verekitug demonstrating a reduction in AAER of 56% when dosed at 100 mg q12w and 39% when dosed at 400 mg q24w, as compared with placebo. Placebo-adjusted improvement in lung function, as measured by the forced expiratory volume in one second, or FEV1, was 122 mL at week 60 with verekitug 100 mg q12w, and 139 mL at week 60 with 400 mg q24w. At week 60, verekitug also suppressed exhaled nitric oxide, or FeNO, compared to placebo by 20.4 ppb when dosed at 100 mg q12w, and by 26.3 ppb when dosed at 400 mg q24w. These data represented a mean 43.5% reduction from baseline in the 100 mg q12w group and a mean 44.9% (p=0.03) reduction from baseline in the 400 mg q24w group. A third low-dose treatment group, 100 mg q24w, demonstrated a statistically significant effect on AAER, but did not provide consistent improvements in other endpoints. Additional pre-specified analyses of secondary outcomes at week 24 revealed statistically significant placebo-adjusted improvements compared to baseline in both FEV1 and FeNO with the 100 mg q12w and 400 mg q24w dose regimens. Verekitug was generally well tolerated across all active doses, demonstrating a favorable safety profile consistent with previous studies. VALIANT is a Phase 2 global, randomized, double-blind, placebo-controlled, dose-ranging, parallel group clinical trial that evaluated the safety and efficacy of verekitug for up to 60 weeks, with a minimum of 24 weeks of treatment, in 478 patients with severe asthma.