Bharat Biotech, a global leader in vaccine innovation, developing vaccines for infectious diseases, announced the first interim analysis of its BBV152 (COVAXIN®). The whole virion inactivated COVID-19 vaccine candidate demonstrated an interim vaccine efficacy of 81% in its Phase 3 clinical trial. The trials involved 25,800 subjects, the largest ever conducted in India, in partnership with the Indian Council of Medical Research.
BBV152 contains a whole virion inactivated SARS-CoV-2 vaccine, which is produced in Vero cells. It is stable at 2 to 8°C (refrigerated) and is shipped in a ready-to-use liquid formulation that permits distribution using existing vaccine supply chain channels. BBV152 has a 28-day open vial policy as a unique product characteristic, thus reducing vaccine wastage by approximately 10-30%. BBV152 is based on an established manufacturing platform with a better safety profile when compared to other vaccine platforms. The inclusion of the Algel-IMDG adjuvant enhances T-cell immune responses to COVID-19, leading to long-term protection.
The Phase 3 study enrolled 25,800 participants between 18-98 years of age, including 2,433 over the age of 60 and 4,500 with comorbidities. The primary endpoint of Phase 3 clinical trial is based on the first occurrence of PCR-confirmed symptomatic (mild, moderate, or severe) COVID-19 with onset at least 14 days after the second study vaccination in serologically negative (to SARS-CoV-2) adult participants at baseline. The first interim analysis is based on 43 cases, of which 36 cases of COVID-19 were observed in the placebo group versus 7 cases observed in the BBV152 (COVAXIN®) group, resulting in a point estimate of vaccine efficacy of 80.6%.
The interim analysis included a preliminary review of the safety database, which showed that severe, serious, and medically attended adverse events occurred at low levels and were balanced between vaccine and placebo groups. The trial’s conduct and monitoring are as per Good Clinical Practice guidelines and have been outsourced to IQVIA. Analysis from the National Institute of Virology indicates that vaccine-induced antibodies can neutralize the UK variant strains and other heterologous strains, which has been published in bioRxiv. https://doi.org/10.1101/2021.01.26.426986
Bharat Biotech expects to share further details of the trial results as additional data become available. An additional interim analysis is planned for 87 cases, and the final analysis is planned for 130 cases. All data from the second interim and final analyses will be shared via prepublication servers as well as submitted to a peer-reviewed journal for publication.