Brii Biosciences today announced that its monoclonal antibody combination therapy, BRII-196 and BRII-198, met pre-specified safety and efficacy criteria, permitting continuation of Phase 3 of the ACTIV-2 trial as recommended by a DSMB composed of independent subject matter experts.
BRII-196 and BRII-198 are non-competing SARS-CoV-2 neutralizing antibodies derived from convalesced COVID-19 patients. They have been specifically engineered to reduce the risk of antibody-dependent enhancement and prolong the plasma half-lives for potentially more durable treatment effect. Their non-overlapping epitope binding regions provide a high degree of neutralization activity against SARS-CoV-2, with preliminary in vitro evidence suggesting continued antiviral activity against commonly circulating variants from U.K. and South Africa.
This recommendation is based on an analysis reviewed by the DSMB of approximately 220 patients enrolled in the Phase 2 portion of the study. Pre-defined safety and efficacy criteria, including assessments of antiviral activity and clinical efficacy, relative to placebo, were evaluated during this review in ambulatory patients with COVID-19 at high risk for progression to severe disease. Brii Biosciences, the study team and the Study Sponsor, the National Institute of Allergy and Infectious Diseases (NIAID), remain blinded to the data reviewed by the DSMB.
The Phase 3 portion of the study, which has been actively enrolling participants, is expanding into international trial sites, allowing for a broader assessment of the BRII-196 and BRII-198 combination in ambulatory COVID-19 patients, potentially including data against newly emerged SARS-CoV2 variants endemic to those countries.