Hyderabad-based pharmaceutical company Bharat Biotech on Friday said it had successfully conducted clinical trials of its potential coronavirus vaccine, or Covaxin, on animals. The company said no adverse effects were seen in animals who were immunised with a two-dose regimen of the vaccine.
In a statement released on Friday, the pharmaceutical firm said the data from the study on primates substantiate the immunogenicity of Covaxin. It added that the results demonstrated the protective efficacy of the vaccine in a live viral challenge model.
The company said a two-dose vaccination regimen of inactivated SARS-CoV-2 vaccine candidates was administered in rhesus macaques, a species of the Old World Monkey. Twenty macaques were divided into four groups of five animals each.
While one group was administered with the placebo, three groups were immunised with three different vaccine candidates at zero and 14 days. All the macaques were exposed to viral challenge 14 days after they were given the second dose.
“The results showed protective efficacy, increasing SARS-CoV-2 specific IgG and neutralizing antibodies, reducing replication of the virus in the nasal cavity, throat, and lung tissues of monkey,” the statement added. “No evidence of pneumonia was observed by histopathological examination in vaccinated groups, unlike the placebo group.”
“To summarize, the vaccine candidate was found to generate robust immune response,” Bharat Biotech added. “Thus, preventing infection and disease in the primates upon high amounts of exposure to live SARS-CoV-2 virus.”
The human clinical trials of Bharat Biotech’s experimental vaccine are also underway. It was the first indigenous vaccine candidate to get the Drug Controller General of India’s approval forPhase I and Phase II clinical trials on June 29. On July 3, the Indian Council for Medical Research wrote to 12 hospitals and medical institutions to speed up the trial process and launch Covaxin by August 15 for public use. The move was decried by health and medical experts who said the ICMR’s proposed timeline would compromise patient safety and ethics.
Covaxin was developed by Bharat Biotech in collaboration with the Indian Council of Medical Research and the National Institute of Virology. It is an inactivated vaccine created from a strain of the infectious SARS-CoV-2 virus. Inactivated vaccines use the killed version of the germ that causes a disease. It helps the immune system mount an antibody response towards virus.