COVAXIN shows interim efficacy of 81% against coronavirus in Phase 3 clinical trials, says Bharat Biotech

Bharat Biotech said their indigenously developed coronavirus vaccine, COVAXIN, has demonstrated an interim vaccine efficacy of 81 percent in Phase 3 clinical trials. Bharat Biotech issued a press release on Wednesday announcing the first interim analysis which is based on 43 cases. Out of the 43, 36 cases of COVID-19 were observed in the placebo group versus seven cases observed in the BBV152 (Covaxin) group, resulting in a point estimate of vaccine efficacy of 80.6 percent. The interim analysis, the company added in the statement, 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 company also said that analysis from the National Institute of Virology indicates that “vaccine-induced antibodies can neutralise the UK variant strains and other heterologous strains”. This analysis has been been published in bioRxiv, a preprint repository for papers. Reports in bioRxiv are not peer-reviewed. The company had earlier published an interim analysis based on phase one data on The Lancet. The company also stated that it expects to share further details of the trial results as additional data become available. “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 pre-publication servers as well as submitted to a peer-reviewed journal for publication,” it added in a statement. According to information provided by Bharat Biotech with Firstpost, 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 phase three clinical trials were conducted in partnership with the Indian Council of Medical Research, the Hyderabad-based company said in the statement. Significant immunogenicity against emerging variants, says MD Krishna Ella Announcing the efficacy results Bharat Biotech chairman and managing director Krishna Ella said, “Today is an important milestone in vaccine discovery, for science and our fight against coronavirus. With today’s results from our Phase 3 clinical trials, we have now reported data on our COVID-19 vaccine from Phase 1, 2, and 3 trials involving around 27,000 participants.”

Covaxin demonstrates a high clinical efficacy trend against COVID-19 but also significant immunogenicity against the rapidly emerging variants , he added. ICMR said that the efficacy results have brought India one step closer to “winning the fight” against COVID-19.

A great win for Atmanirbhar Bharat! India’s indigenously developed #COVAXIN shows 81% interim efficacy in Phase 3 trial. We are now one step closer to winning the fight against COVID-19. #Unite2FightCOVID @MoHFW_India @PMOIndia @drharshvardhan @PIB_India @BharatBiotech pic.twitter.com/jVKYy0Tsm1

— ICMR (@ICMRDELHI) March 3, 2021

The vaccine, which has been indigenously developed by Bharat Biotech in collaboration with ICMR, is among the two vaccines that are being administered in the country. The Phase 3 trial results assume significance as the company had approached the Central Drugs Standard Control Organisation (CDSCO) for approval to conduct late-stage clinical trials of Covaxin in children aged 5-18, according to a report in The Indian Express. Covaxin was approved without the efficacy data for restricted use in an emergency situation by the Drug Controller General of India on 3 January as the company had not finished recruiting and vaccinating enough participants for Phase 3 trials. Experts had questioned the approval without phase three clinical trials data . The efficacy data based on an interim analysis of phase three clinical trials data is likely to allay some of those concerns. So far, healthcare and frontline workers have been inoculated with the Covaxin “in clinical trial mode” as part of the Centre’s mass vaccination drive against the coronavirus. The vaccine is also being distributed to several other countries across the world. The vaccine known as BBV152, contains a whole virion inactivated SARS-CoV-2 vaccine, which is produced in Vero cells. It uses Algel-IMDG as adjuvant. 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.