Brii Biosciences Monoclonal Antibodies, BRII-196 and BRII-198, Progress to Phase 3 in NIH ACTIV-2 Trial in Ambulatory COVID-19 Patients

- Independent data safety monitoring board (DSMB) formally recommends investigational combination therapy advance to Phase 3 following Phase 2 pre-specified analysis for safety and efficacy

- Currently enrolling Phase 3 study enables expansion into a broad range of international trial sites

DURHAM, N.C., United States and BEIJING, China – 29 April 2021 Brii Biosciences (“Brii Bio”), a multi-national company developing innovative therapies for diseases with significant unmet medical needs and large public health burden, 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.

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.

“This recommendation by the independent DSMB is encouraging and marks an important milestone for Brii Bio as we continue to gather a broad range of data and advance this important investigational combination therapy for COVID-19 patients around the world,” said Zhi Hong, Ph.D., CEO of Brii Bio. “As BRII-196 and BRII-198 are the first to progress to Phase 3 evaluation in the ACTIV-2 trial, we look forward to adding international trial sites to this study, which is especially critical for regions experiencing a surge in COVID-19 cases and new variants.”

About ACTIV-2

The ACTIV-2 trial (NCT04518410) is sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), one of the divisions of the National Institutes of Health (NIH), and is led by the NIAID-funded AIDS Clinical Trials Group (ACTG). ACTIV-2 is part of NIH’s Accelerating COVID-19 Therapeutic Interventions and Vaccines (ACTIV), a public-private partnership program to create a coordinated research strategy that prioritizes and speeds development of the most promising treatments and vaccines.

The ACTIV-2 master protocol evaluates the safety and efficacy of investigational agents for the treatment of symptomatic non-hospitalized adults with COVID-19 under a randomized, blinded, controlled adaptive platform. Participants identified as being at high risk for progression to more severe disease, are eligible for enrollment onto BRII 196/198 or placebo. Phase 3 evaluation is a continuation of the Phase 2 trial for agents that meet study-defined criteria for further evaluation. Phase 3 of the study is designed to determine if the investigational agent, combination BRII-196 and BRII-198, will prevent the composite endpoint of either hospitalization or death through study day 28.

About BRII-196 and BRII-198

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. Phase 1 studies in healthy human volunteers in China have completed dosing and follow-up, providing safety and human pharmacokinetic profiles for both individual antibodies.

The BRII-196 and BRII-198 antibody cocktail is in Phase 3 clinical investigation as part of the ongoing NIH ACTIV-2 trial (NCT04518410). Investigational New Drug applications have been submitted for the combination therapy to the U.S. Food and Drug Administration (FDA), the Department of Health in Hong Kong, and to the China National Medical Products Administration (NMPA).

About Brii Biosciences

Brii Biosciences (Brii Bio) is a multi-national company committed to serving patients' needs and improving public health by accelerating the development and delivery of breakthrough medicines through partnerships, best-in-class research and development, and the disruptive application of digital and data insight. With operations in the People's Republic of China and the United States, Brii Bio is poised to serve as a bridge to carry transformative medicines to patients, help create significant growth for our partners and establish an innovation engine to help improve the public health and wellbeing of patients around the world. Brii Bio is developing treatments for illnesses with significant public health burdens, including infectious diseases and CNS diseases. For more information, visit