Hyderabad: Indigenously developed Covaxin has an overall efficacy of 77.8% against symptomatic Covid-19 and is 65.2% effective against the Delta (B.1.617.2) variant that was first detected in India, its developer Bharat Biotech said on Saturday.
Also, Covaxin is 93.4% effective against severe symptomatic Covid-19 infection and offers 63.6% protection to asymptomatic patients, Bharat Biotech said revealing the final analysis of the phase III trials conducted on 25,800 participants aged between 18 and 98 years pan-India.
The vaccine also showed a higher efficacy of 79.4% in those below 60 years as compared with 67.8% in those aged 60 and above. The results were published in preprint server MedRxiv. The company said the overall efficacy of 77.8% was arrived at after 130 confirmed Covid cases were reported among trial participants, which included 24 participants who got both doses of Covaxin and 106 volunteers who received placebo shots.
Pointing out that no cases of anaphylaxis or vaccine-related deaths were reported, it said, “Overall rate of adverse events observed in Covaxin was lower than that seen in other Covid-19 vaccines… adverse events reported were similar to placebo, with 12% of subjects experiencing commonly known side-effects and less than 0.5% feeling serious adverse events.”
Bharat Biotech said Covaxin was the first to report promising efficacy against asymptomatic infections, which will reduce disease transmission. “No licensed SARS-CoV-2 vaccine has reported efficacy against asym-ptomatic infection in a randomised controlled trial based on qPCR testing,” it said.
Bharat Biotech chairman Dr Krishna Ella said, “The successful safety and efficacy readouts of Covaxin establish the ability of India and developing countries to focus on innovation and novel product development. We are proud to state that innovation from India will now be available to protect global populations.”