India has approved Hyderabad-based drugmaker Biological E’s coronavirus vaccine as the first mix-and-match booster dose in the country, the company announced on Saturday.

The Drugs Controller General of India gave approval for the Corbevax vaccine to be administered as a booster shot to individuals aged 18 years and above, six months after they have already received two doses of either Serum Institute’s Covishield or Bharat Biotech’s Covaxin.

A statement said that Corbevax is the first such vaccine in India to be approved as a heterologous Covid-19 booster. A heterologous booster is when individuals are administered a dose of a different vaccine than what was used in the primary vaccination, according to the World Health Organization.

So far, in India the third dose had to be of the same vaccine used for the first and second shot.

Corbevax is made up of the coronavirus’ “spike protein”, which the virus uses to latch on and enter human cells. When injected, this is expected to trigger an immune response in the body.

“BE’s clinical trial data showed that the Corbevax booster dose provided significant enhancement in immune response and excellent safety profile required for an effective booster,” the company said on Saturday.

The approval came after Biological E conducted a clinical trial involving 416 volunteers between 18 and 80 years of age.

“The booster dose of Corbevax increased the neutralising antibody titers in the Covishield and Covaxin groups significantly when compared to placebo,” it said. A neutralising antibody offers protection from infection with the Sars-CoV-2 variants.

“The Corbevax heterologous booster vaccine was well tolerated and safe,” the company added. “There were no severe or adverse events of interest for three months of follow-up after the booster dose was administered.”

Corbevax is entirely developed and manufactured by Biological E Limited in association with Texas Children’s Hospital and Baylor College of Medicine as a recombinant protein sub-unit vaccine against Covid-19. The company has supplied 100 million doses of the Corbevax to the Indian government.

In February, the Drugs Controller General of India gave emergency use authorisation to Corbevax for those aged between 12-18 years. In April, the drug regulator gave the vaccine emergency use authorisation for the 5-12 age group.

India made precautionary doses of Covid-19 available for adults at private vaccination centres from April 10. The booster jabs were first administered to healthcare workers and frontline workers in January.

Corbevax will address the need for Covid-19 booster doses in India, said Mahima Datla, managing director, Biological E Limited.

On Saturday, India reported 3,962 new coronavirus cases. The country’s active caseload stood at 22,416, according to the health ministry.

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