China’s Brii Biosciences (HKG: 2137) has announced the publication of interim results from a Phase II study for its small interfering RNA (siRNA) drug candidate BRII-835 (VIR-2218) combined with BRII-179 (VBI-2601), an immuno-therapeutic drug candidate co-developed by VBI Vaccines, in chronic hepatitis B virus (HBV). The combination therapy induced a stronger anti-hepatitis B surface antigen (HBsAg) antibody response and improved HBsAg-specific T cell response compared to single drug treatments.
Interim Results and Observations
At the 40th week of the study, it was observed that the level of HBsAg in two subjects in the combined treatment group decreased to at or below the lower limit of quantification. Additionally, a robust HBsAg-specific antibody response and T-cell response were observed. These results suggest that the combination therapy may offer significant benefits over monotherapy in the treatment of chronic HBV.
BRII-835: Investigational siRNA for HBV
BRII-835, an investigational subcutaneous siRNA originated by Vir Biotechnology (NASDAQ: VIR) to treat HBV, is the first of its kind in the clinics containing enhanced stable chemical potentiation (ESC+) technology. This technology is designed to improve stability and minimize off-target activity, which is expected to improve the treatment index. Brii Bio struck a licensing deal with Vir in 2020 to take exclusive development and commercialization rights to the drug in Greater China.
BRII-179: Immuno-Therapeutic Drug Candidate
BRII-179 is formulated to target both B-cell and T-cell immunity through multiple mechanisms of action. These include neutralizing the circulating hepatitis B virus, blocking hepatitis B infection of hepatocytes mediated through Pre-S1, and enabling immune-mediated clearance of HBV-infected hepatocytes. The antigenic components of BRII-179 (VBI-2601) are the same as the three antigenic components of the preventive hepatitis B recombinant vaccine PreHevbrio, developed by VBI Vaccines, which has been approved for marketing in the United States.
Functional Cure for HBV Infection
Brii Bio is also developing the combination therapy as a functional cure for HBV infection. Further data from the study is expected to be released later this year, providing more insights into the potential of this innovative treatment approach.-Fineline Info & Tech