COVAXIN successfully completes phase 2/3 trials in U.S.

The Pennsylvania, U.S.-based NASDAQ-listed biotech company Ocugen Inc has announced positive results of the Phase 2/3 trials of Hyderabad-based vaccine major Bharat Biotech's COVID-19 vaccine candidate, COVAXIN, in the U.S. The top-line data from the study is believed to be critical to support Ocugen’s future plans for developing COVAXIN in the U.S.

Ocugen and Bharat Biotech had tied up to co-develop, supply, and commercialise COVAXIN in the United States market in February 2021. COVAXIN has been developed by Bharat Biotech with the Indian Council of Medical Research (ICMR) – National Institute of Virology (NIV). The vaccine is manufactured using a vero cell manufacturing platform and was among the first jabs to be approved for mass vaccinations in India.

Ocugen, which focuses on discovering, developing, and commercialising novel gene and cell therapies and vaccines, said COVAXIN (BBV152) uses the same vero cell manufacturing platform that has been used in the production of “polio vaccines” for decades. The clinical trials of the vaccine showed a broader immune response against the whole virus covering important antigens such as "S-protein, RBD, and N-protein; whereas currently approved vaccines in the U.S. target only S-protein antigen", a statement said.

“The successful completion of this study represents an important milestone to the ongoing management of COVID-19,” said Dr Shankar Musunuri, chairman, chief executive officer, and co-founder of Ocugen. He said the vaccine could be a great alternative for those in the U.S. who are hesitant to receive mRNA vaccines. “Given that a portion of the public remains hesitant to receive mRNA vaccines, this investigational COVID-19 vaccine candidate, which relies on a well-established approach to vaccine development and manufacturing, may provide an important additional vaccine option.”

The study enrolled 419 U.S. adult participants that were randomised 1:1 to receive two doses of COVAXIN or placebo, 28 days apart. "Blinded safety results and preliminary unblinded immunogenicity results are available through Day 56, one month following the second vaccination," Ocugen said.

Meanwhile, apart from India, COVAXIN has also been approved for emergency use in 25 countries, with over 350 million doses administered to adults outside the U.S. to date, the company said. It had also applied for authorisation in over 60 more countries.

Findings of phase 2/3 trials in U.S.

The results of the study in the U.S. were compared with the results of the COVAXIN-vaccinated participants in the Bharat Biotech-sponsored Phase 3 study in India. "Approximately 24% of tested participants in the U.S. were vaccine-naïve, while all participants in the Bharat Biotech Phase 3 study were vaccine-naïve."

Immune responses were adjusted for differences between the U.S. and Indian cohorts in baseline neutralising antibody, body mass index, gender, and age.

Ocugen said, "Blinded safety data are also available for one month following vaccination". "There were no deaths, related potential immune-mediated medical conditions, or related adverse events of special interest."

There were also no cases of myocarditis, pericarditis, thrombotic events, or Guillain-Barré syndrome, the findings showed. "Thirty medically attended adverse events in 18 subjects and two serious adverse events in one subject were reported, and all were considered unrelated to vaccination," the company said.

Dr Eric Feigl-Ding, epidemiologist and health economist, chief of the COVID Task Force at the New England Complex Systems Institute, and co-founder of the World Health Network, said the trial data represents an important step in the management of the ever-evolving COVID-19 pandemic. He added that the need for different vaccine approaches to COVID-19 has become critically apparent with the continued emergence of variants.