US biotechnology major Novavax on Wednesday said two large phase-3 trials of its Covid -19 vaccine being manufactured by Pune-based Serum Institute of India have shown that the jab provides high levels of protection against mild, moderate, and severe infection.

Speaking at SII, Dr Gregory Glenn, president of Research and Development at Novavax, claimed the vaccine will work against "yesterday's, today's, and most importantly, tomorrow's strains of coronavirus".

A USA delegation of Dr Glenn, USA Mission Charg d'Affaires Patricia Lacina, USA Consul General in Mumbai Mike Hankey, Novovax Inc CEO Stanley C. Erck, and others visited the SII headquarter to celebrate 75 years of the US-India bilateral partnership.

SII and Novavax are the key partners in the development and manufacturing of the Novavax vaccine, marketed by Novavax as Nuvaxovid and by SII as Covovax , from its facility in Pune.

Unfortunately, we believe Covid-19 is here to stay, and we are seeing the shift to a more endemic disease landscape that will persist, continue to evolve, and give us new variants that can escape immunity, said Dr Glenn while sharing some background on their COVID-19 vaccine, ongoing trials and the future plans.

He said Novavax's COVID-19 vaccine leverages a well-defined platform yet with major innovations, and thereby offers a differentiated vaccine option to meet this ongoing need within the USA, and globally.

The Novavax vaccine, now manufactured by Serum Institute, was shown in two large phase-3 trials to provide high levels of protection against mild, moderate, and severe COVID-19, and both results were published in the NEJM (New England Journal of Medicine)," he said.

Talking about the trials conducted in the US, and Mexico, he said the vaccine has been generally well tolerated with a reassuring safety profile across a large and diverse patient population.

Dr Glenn further said the study was conducted with a vaccine based on the original Wuhan spike protein sequence.

"Importantly, several variants emerged and circulated during the efficacy evaluation phase of the trial, allowing us to assess efficacy against variants. In fact, the majority of cases seen were attributed to variants of concern or variants of interest. This study demonstrated the overall efficacy of 90.4 per cent against symptomatic disease against this mosaic of variants and achieved 91 per cent efficacy in high-risk populations with medical comorbidities," he said.

All events of severe Covid disease and hospitalisations occurred in the placebo group, he said.

Dr Glenn added that as the pandemic has further evolved, their data shows that the prototype, the current strain vaccine induces broad recognition of new variants, especially with boosting.

"This has profound future implications, as we strongly believe that the vaccine we have in our hands today will work against yesterday's, today's, and most importantly, tomorrow's strains. As you know, the Wuhan was replaced by waves of alpha, beta, delta, omicron, its sub-variants, BA.2, and now BA.5, which appears to have plateaued. So the vaccine must be about the future," he said.

Speaking about the research on boosters, Dr Glenn claimed that studies showed that their prototype strain vaccine, provoke even more antibodies to the unchanging parts of the spike protein.

"Thus, the antibody responses after boosting recognise the new variants as well as they recognised the original spike in the Phase 3 trials. Because one certainty amid the changing pandemic is that the virus will change and people need to receive a booster shot," he said.

Based on the research data, the vaccine has been authorised for use as a booster in several countries, including Japan and Australia.

He also said that an application has been submitted to the US FDA for Emergency Use Authorisation for the Covid -19 vaccine as a booster in adults.

"We hope this application will be reviewed with urgency by the agency. And we hope the USA will be able to take advantage of the Novavax vaccine produced by Serum Institute as a booster this fall, should it be FDA-authorised," said Dr Glenn.

In addition to their Covid -19 vaccine, Novavax's pipeline includes a Covid -19 -influenza combination vaccine and vaccines for influenza and RSV.

"We stand ready to address newly emerging challenges. As you know, we have also partnered with Serum Institute on a malaria vaccine," he added.