Covaxin, the indigenously developed Covid-19 vaccine, developed by the ICMR and Bharat Biotech International, has been found to be effective in non-human primates, according to Phase 1 of its cliical trials in India.

Adverse events were not seen in animals immunized with a two-dose vaccination regimen. (File photo: Reuters)

Covaxin has demonstrated protective efficacy and immunogenicity in non-human primates in Phase I clinical trials in India. Covaxin, the indigenously developed Covid-19 vaccine, developed by the ICMR and Bharat Biotech International, is being tested at 12 institutes across India. The results of the first phase of testing are encouraging

A two-dose vaccination regimen of inactivated coronavirus vaccine candidates was administered in 20 rhesus macaques (divided into four groups equally).

BBIL’s #Covaxin(BBV152) found protective in Macaques: A two-dose vaccination regimen using 3µg dose of the vaccine with adjuvant B induce a significant immune response and provide effective protection in macaques challenged with #SARSCoV2 https://t.co/FgSnD2eCmA pic.twitter.com/hQHh2klAnX

— Vipin M. Vashishtha (@vipintukur) September 11, 2020

One group was administered with placebo, while three groups were immunized with 3 different vaccine candidates at 0 and 14 days. All the macaques were exposed to viral challenge 14 days after the 2nd dose.

The results showed protective efficacy, increasing coronavirus specific IgG and neutralizing antibodies, reducing replication of the virus in the nasal cavity, throat, and lung tissues of monkey.

Remarkable immunogenicity and protective efficacy of BBV152, an inactivated SARS-CoV-2 vaccine in rhesus macaques https://t.co/b82dA6QlcW ICMR-NIV made very good effort to demonstrate potential immunogenicity in non-human Primate with BBV152. ! @ICMRDELHI @drharshvardhan

— Dinesh kumar (@Dineshk38263974) September 11, 2020

No evidence of pneumonia was observed by histopathological examination in vaccinated groups, unlike the placebo group.

Adverse events were not seen in animals immunized with a two-dose vaccination regimen.

"To summarize, the vaccine candidate was found to generate robust immune responses. Thus, preventing infection and disease in the primates upon high amounts of exposure to live coronavirus," said a researcher.

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