Opexa MS drug fails to meet endpoints

Texas, USA-based Opexa Therapeutics, a company dedicated to the development of patient-specific cellular therapies for the treatment of autoimmune diseases such as multiple sclerosis and diabetes, presented top-line data showing the firm's Phase IIb TERMS study of lead vaccine candidate Tovaxin failed to meet its endpoints, at the World Congress on Treatment and Research in Multiple Sclerosis in Montreal, Canada.

The study was a multicenter, randomized, double-blind, placebo-controlled trial in 150 patients with relapsing-remitting multiple sclerosis or high-risk, clinically-isolated syndrome. Patients were randomized 2:1 to receive Tovaxin or placebo in a total of five subcutaneous injections at weeks zero, four, eight, 12 and 24. The primary endpoint was the cumulative number of gadolinium-enhanced brain lesions using MRI scans in weeks 28, 36, 44 and 52. The secondary endpoints included annualized relapse rate and additional MRI measurements.

Top-line results from the study showed that Tovaxin-treated patients experienced an ARR of 0.214 as compared to 0.339 for subjects on placebo. Despite the low relapse rate in the placebo arm, this still represented a 37% decrease in ARR for Tovaxin compared to placebo in the general population. Additionally, in the group of patients who had an ARR>1 at study entry, Tovaxin demonstrated a 55% reduction in ARR compared to placebo.