Bharat Biotech's COVID-19 vaccine Covaxin (BBV152) is effective against Delta Plus (AY.1) variant of the coronavirus, according to a study by the Indian Council of Medical and Research.
"ICMR study shows #Covaxin is effective in Delta, Delta AY.1 and B.1.617.3 variants," the apex health research body said in a tweet.
"Here, we have evaluated the IgG antibody titer and neutralizing potential of sera of COVID-19 naive individuals full doses of BBV152 vaccine, COVID-19 recovered cases with full dose vaccines and breakthrough cases post-immunization BBV152 vaccines against Delta, Delta AY.1 and B.1.617.3.," the study said.
The recent emergence of the SARS-CoV-2 Variant B.1.617.2 (Delta) variant with its high transmissibility has led to the second wave in India.
Covaxin, a whole-virion inactivated SARS-CoV-2 vaccine used for mass immunization in the country, showed a 65.2 per cent protection against the Delta variant in a double-blind, randomized, multicentre, phase 3 clinical trial.
Subsequently, Delta has further mutated to Delta AY.1, AY.2, and AY.3.
Of these, AY.1 variant was first detected in India in April 2021 and subsequently reported from 20 other countries as well, the study said.
"The results of the study reveal covaxin neutralises the Delta, Delta AY.1 and B.1.617.3 variants effectively," the ICMR stated.
The study has been published on biorxiv, a pre-print server and has not been peer reviewed.
Covaxin demonstrated 77.8 per cent effectiveness against symptomatic COVID-19 and 65.2 per cent protection against the B.1.617.2 Delta variant, Bharat Biotech had said while concluding the final analysis of Covaxin efficacy from Phase-3 trials on July 3.