Drug Action Network questions data on safety, efficacy of vaccines

Chennai

Members of AIDAN claimed that as Covaxin remains in the clinical stage with recruitment for the third phase still under way, there is a need to know the efficacy estimates for the dosing regimen and schedule that will be followed in India if it is administered. “As Covaxin remains in the clinical stage, the efficacy data for the vaccine candidate submitted available through publication pre-prints, are for safety and immunogenicity from Phase 1 and Phase 2 trials, across a total of 755 participants. Thus, there is a lack of human data on Phase 3 trials which is a concern,” a representative from AIDAN stated.

He added that it was also not clear if there was any scientific basis to claim that Covaxin will be effective in dealing with the mutant strains when its efficacy has not been established and is currently unknown against any strain of the virus.

Dr Sathyajit Mohapatra, who is leading the Covaxin trials at SRM Medical College and Research Centre said that the vaccine has been recommended only for restricted emergency use as it has been found safe in Phase 1 and Phase 2. “Emergency use implies that if we have more than expected cases in a time of a medical emergency and there isn’t adequate stock of Covidshield, Covaxin can be used as an alternative. Meanwhile, research continues and no major side effects have been reported yet,” he told DT Next. Senior AIIMS scientist Dr Vivek Dixit said that safety has to be prioritised over efficacy and in an emergency, the use of the vaccine can be considered. “We need to work on preparatory measures in view of the new strains or any medical emergency. In such a scenario, we can recommend the vaccine found to be 97% safe in Phases 1 and 2. If there is no emergency, the approval can be completed once there is more academic research data,” he added.