BioCryst Pharmaceuticals, Inc. today announced that it has dosed the first patient in OPuS-2 (Oral ProphylaxiS-2), a blinded, randomized, placebo-controlled clinical trial of orally-administered BCX4161 in patients with HAE.
OPuS-2 is a 12-week, three-arm, parallel cohort design trial to evaluate the efficacy and safety of two doses of BCX4161, 300 mg and 500 mg, administered three-times daily compared with placebo. This trial, to be conducted in the U.S. and selected European countries, is expected to enroll approximately 100 HAE patients. The primary efficacy endpoint for the trial will be the mean angioedema attack rate for each BCX4161 dose group compared to placebo.
“The OPuS-2 trial will provide important information on the efficacy and safety of 12 weeks of oral BCX4161 for prevention of angioedema attacks in HAE patients. OPuS-2 builds on the positive efficacy, safety, tolerability, drug exposure and kallikrein inhibition results from the OPuS-1 4-week study,” said Dr. Marc Riedl, M.D., M.S., Associate Clinical Professor at the University of California-San Diego School of Medicine, Clinical Director of the U.S. HAEA Angioedema Center and OPuS-2 Principal Investigator.
“OPuS-2 has been designed as an adequate and well-controlled study and represents an important next step toward reaching our goal of improving HAE patients’ lives using oral kallikrein inhibitors,” added Dr. William P. Sheridan, Chief Medical Officer at BioCryst.
In May 2014, BioCryst announced positive results from the OPuS-1 (Oral ProphylaxiS-1) proof of concept Phase 2a clinical trial of orally-administered BCX4161 in patients with HAE. The trial met the primary efficacy endpoint, several secondary endpoints and all other objectives established for the trial. The primary efficacy endpoint for the trial was the by-subject difference in mean angioedema attack rate on BCX4161 compared to placebo. Treatment with BCX4161 demonstrated a statistically significant mean attack rate reduction of 0.45 attacks per week versus placebo, p<0.001. The mean attack rate per week was 0.82 on BCX4161 treatment, compared to 1.27 on placebo. Discovered by BioCryst, BCX4161 is a novel, selective inhibitor of plasma kallikrein in development for prevention of attacks in patients with HAE. By inhibiting plasma kallikrein, BCX4161 suppresses bradykinin production. Bradykinin is the mediator of acute swelling attacks in HAE patients.