Hyderabad-based pharmaceutical company Bharat Biotech said its COVID-19 vaccine, Covaxin, shows an overall interim clinical efficacy of 78% as part of its phase-three clinical trial. It also said that the vaccine demonstrated strong primary efficacy against severe COVID-19 disease, showing a 100% interim efficacy. This is the second interim result of the phase-three clinical trial, released by Bharat Biotech released on Wednesday. It must be noted that 78% efficacy means it reduces the number of cases or chances of contracting the disease by 78% among the vaccinated group of individuals.
In March 2020, Bharat Biotech released the first interim result of the phase-three clinical trial, which had shown an interim vaccine efficacy of 81%. Covaxin is an indigenously developed vaccine against COVID-19. It is one of the two COVID-19 vaccines (Serum Institute of India’s Covishield) that are currently administered in India. The phase-three clinical study has 25,800 participants between 18-98 years of age, including 10% over the age of 60, with analysis conducted 14 days after the second dose. The phase-3 clinical trial was co-funded by the Indian Council of Medical Research (ICMR).
The company said that its second interim analysis is based on more than 87 symptomatic COVID-19 cases. “Due to the recent surge in cases, 127 symptomatic cases were recorded, resulting in a point estimate of vaccine efficacy of 78% against mild, moderate, and severe COVID-19 disease,” read a statement from Bharat Biotech.
The efficacy against asymptomatic COVID-19 infection was 70%, suggesting decreased transmission among the persons who received Covaxin. The efficacy of the COVID-19 vaccine against severe COVID-19 disease was 100%, “with an impact on reduction in hospitalisations,” it said.
“Covaxin has demonstrated an excellent safety record in human clinical trials and in usage under emergency use. The efficacy data against severe COVID-19 and asymptomatic infections is highly significant, as this helps reduce hospitalisations and disease transmission, respectively,” said Dr Krishna Ella, Chairman and Managing Director, Bharat Biotech.
Bharat Biotech said it will release its safety and efficacy results from the final analysis in June, while the final report will be submitted to a peer-reviewed publication. “Based on the achievement of the success criteria, placebo recipients have now become eligible to receive two doses of Covaxin,” it added.
Covaxin or BBV152, an inactivated virus-based vaccine, was developed using the seed strains it received from the National Institute of Virology (NIV). It is stable at 2 to 8 degree Celsius (refrigerated). In January 2021, the Drugs Controller General of India (DCGI) granted Emergency Use Authorisation (EUA) approval for Covaxin.
In a newly-released study, the ICMR said that Covaxin neutralises the B.1.1.7 variant of the COVID-19 virus, which was first detected in the United Kingdom in September. ICMR said that its study showed that the sera from the vaccine recipients could neutralise the B.1.1.7 variant, “discounting the uncertainty around potential (immune) escape.” Immune escape or immune evasion happens when an individual’s immune system is unable to respond to the virus or pathogen. Although the study focuses only on the B.1.1.7 variant, ICMR and Bharat Biotech claimed that Covaxin is effective against all variants of the COVID-19 virus, including the double mutant variant detected in India.
“The company’s efforts to further develop Covaxin continues, with clinical trials planned in India and globally to evaluate its safety and immunogenicity in younger age groups, the impact of booster doses, and protection against SARS-CoV-2 variants,” the statement read.
“The capacity expansion has been implemented across multiple facilities in Hyderabad and Bengaluru to reach about 700 million doses per year, one of the largest production capacities for Inactivated viral vaccines worldwide,” it added.
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