Covaxin shows 'positive' results in phase 2/3 studies in US: Ocugen

If approved, will become the first India-developed vax to be commercialised in the US

Moving a step closer to commercialising the first India-developed vaccine in the US, Hyderabad-based Bharat Biotech’s partner Ocugen Inc. has announced positive top line data for the Covid vaccine candidate Covaxin (BBV152) from The phase 2/3 immuno-bridging study.

Nasdaq-listed Ocugen is Bharat Biotech’s partner to commercialise Covaxin in the US, Canada, and Mexico. The two entered into a partnership in February 2021 for the US market, and have since expanded the partnership to include Canadian and Mexico markets as well.

If the studies are successful in meeting endpoints and the US drug regulator approves Covaxin, it would be the first-ever India-developed vaccine to be approved in the US.

Pune-based Serum Institute of India manufactured Novavax’s Covid vaccine in the US. That is, however, a contract manufacturing partnership.

The Phase 2/3 immuno-bridging and broadening study met both co-primary endpoints with robust immune responses, Ocugen claimed. This study enrolled 419 US adult participants that were randomised 1:1 to receive two doses of Covaxin or placebo, 28 days apart.

Bridging studies are designed to demonstrate equivalent immunogenicity, that is exclude a clinically significant difference in the immune response between the population to whom efficacy was shown and the population to whom those efficacy results are extrapolated.

Covaxin was found to be well-tolerated in vaccine-naïve individuals and individuals previously vaccinated with messenger ribonucleic acid (mRNA) vaccines in the US, with no vaccine-related serious adverse events, thrombotic events, or cases of myocarditis or pericarditis, observed Ocugen.

“These positive data represent an important step in the management of the ever-evolving Covid-19 pandemic,” said Eric Feigl-Ding, epidemiologist and health economist, chief of Covid task force at the New England Complex Systems Institute and the chief health economist for MicroClinic International.

“The need for different vaccine approaches to Covid-19 has become critically apparent with the continued emergence of variants to the SARS-CoV-2 virus.”

Covaxin is a whole virus Sars-CoV-2 which has added adjuvants (chemicals that enhance the efficacy of a vaccine). The vaccine candidate uses the same vero cell manufacturing platform that has been used in the production of polio vaccines for decades.

Bharat Biotech has continued its efforts to further evaluate Covaxin in the US and India, the company said. “These datasets provide valuable insights into the safety and immunogenicity of Covaxin globally,” it added.

Ocugen said that Covaxin has demonstrated in clinical trials to generate a broader immune response against the whole virus covering important antigens like S-protein (spike protein), receptor-binding domain, and N-protein, whereas currently approved vaccines in the US target only S-protein antigen. Additionally, Covaxin generates a long-term memory B-cell and T-cell immune response, added Ocugen.

“The successful completion of this study represents an important milestone to the ongoing management of Covid-19,” said Shankar Musunuri, chairman, chief executive officer, and co-founder of Ocugen.

“Given that a portion of the public remains hesitant to receive mRNA vaccines, this investigational Covid vaccine candidate, which relies on a well-established approach to vaccine development and manufacturing, may provide an important additional vaccine option,” he added.

Blinded safety results and preliminary unblinded immunogenicity results are available through Day 56, one month following the second vaccination.

“Immunogenicity results from Covaxin-vaccinated participants in the US were compared with results in Covaxin-vaccinated participants in the Bharat Biotech International Limited (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,” Ocugen said.

Both co-primary immunogenicity endpoints were met, the firm claimed.

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. 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 top line data from the immuno-bridging and broadening study will be critical to support Ocugen’s plans for the development of Covaxin in the US,” the firm said.

Ocugen Inc. stock rallied 16 per cent in pre-market trade on Monday after the biopharmaceutical company announced positive results in a trial of its Covid vaccine Covaxin.