Lancet publishes results of Covaxin phase 2 clinical trials

Hyderabad: MEDICAL journal The Lancet has published Phase 2 clinical trial results of the vaccine candidate BBV152, a vaccine for Covid-19 named Covaxin, developed by city-based Bharat Biotech.

The results of the study titled 'Safety and immunogenicity of an inactivated SARS-CoV-2 vaccine, BBV152L' from a double-blind, randomised, multicentre, phase-2 trial and 3-month follow-up of a double-blind, randomised phase 1 trial' were published in the British journal on Tuesday.

"BBV152 led to enhanced immune responses and induced T-cell responses that were biased to Th1. Due to the difference in dosing regimens between phase 1 (two doses given 2 weeks apart) and phase 2 (two doses given 4 weeks apart) trials, neutralisationresponses were significantly higher in the phase 2 trial than in the phase 1 trial, according to the research paper published in Lancet. According to the Lancet article, the proportion of participants reporting adverse events in the phase 2 trial were lower than in the phase 1 trial.

The study also said that immunological differences between men and women and across age groups were not observed, with both the groups that were administered the vaccine (3 ug with Algel-IMDG and 6 ug with Algel-IMDG) having similar safety outcomes.

While the phase 1 study involved 375 volunteers in the 18-55 years age group at 11 sites, the phase 2 study was conducted on 380 participants in the 12-65 years age bracket at nine sites. However, the number of volunteers in the 12-18 years and 55-65 years group were smaller in number.

On the basis of superior cell-mediated responses in the phase 1 trial, the 6 μg with Algel-IMDG formulation was selected for the phase 3 efficacy trial, which involves 25,800 volunteers and is currently underway.