Expert series: The truth about COVID-19 variants
(BPT) - By Shankar Musunuri, PhD, MBA, Chairman, CEO and Co-Founder, Ocugen
After a summer of hope, the COVID-19 positivity rate has been spiking in the United States. Due in part to the highly transmissible and fast-spreading Delta variant, the number of cases of COVID-19 is up more than 107% vs. July 20, 2021, according to the August 25 weekly data tracker from the Centers for Disease Control and Prevention (CDC). While the vaccines were enormously helpful in slowing the spread of COVID-19 and reducing the death rate, it is now clear that these vaccines, all of which are based exclusively on the ‘spike’ protein portion of the virus, have waning efficacy against variants — specifically Delta. In fact, a recent CDC study found that mRNA vaccine effectiveness has declined from 91% before Delta was the predominant strain in the U.S. to 66% since this strain became predominant.
Why? In simple terms, viruses mutate to survive, and every variant of concern to date has mutations to their spike protein. With every successive variant and mutation to spike we may see vaccines based exclusively on the spike protein portion of the virus lose some of their effectiveness. As the head of the CDC recently pointed out, variants capable of evading today’s vaccines could be just a few mutations away.
Today the U.S. has a large supply of COVID-19 vaccines, both mRNA and adenovirus based. The concern is that this supply consists exclusively of spike protein-based vaccines — precisely the protein SARS–CoV–2 variants are mutating against. We are in the process of developing a vaccine that is based on the whole SARS–CoV–2 virus which has the potential to provide broader coverage and protection from variants.
Our investigational product is called CovaxinTM, an inactivated whole virus vaccine which we believe recently showed clinical efficacy against the Delta variant and severe disease in a large (25,800 person) trial in India, conducted at a time when the Delta variant was the primary strain in that country. A preprint of the study can be found on medRxiv and has been submitted to The Lancet for peer-reviewed publication. These types of vaccines are considered the traditional method used to help stop pandemic viruses. In 1954, Jonas Salk developed the first polio vaccine known as an inactivated poliovirus vaccine. The concept was simple and remarkably effective: take the whole polio virus, inactivate it, attach an adjuvant that creates a strong immune response and let the body’s immune system remember the entire virus so it can ward off future infection, including variants. Through the use of the whole virus inactivated vaccine for polio, which children routinely get to this day, this horrible disease has been eradicated.
Could such a vaccine do the same for COVID-19? We believe so, which is why we partnered with Bharat Biotech to develop CovaxinTM, an investigational vaccine that has been studied for its effect against serious disease as well as the Delta variant. CovaxinTM is not yet authorized or approved in the U.S. or Canada, but it is authorized or approved in 16 countries and more than 50 million doses have been administered to date.
But do Americans really want another COVID-19 vaccine? That’s one of the questions we asked in a recent survey, commissioned by Ocugen and conducted online by The Harris Poll among more than 2,000 Americans between July 26-28, 2021. The answers were pretty straightforward. Many unvaccinated Americans said they have not gotten the vaccine because they are worried about the short- and/or long-term effects of the current vaccine (59%) and would be more likely to get a COVID-19 vaccine (primary or booster) if there was an option with fewer side effects (58%). Interestingly these feelings were similar for both vaccinated and unvaccinated Americans when it comes to their children (49% of parents with children under 18 would be more likely to get their children vaccinated if there were an option with fewer short-/long-term side effects).
Here are a few highlights from the survey among Americans overall:
- 71% would like to see additional COVID-19 vaccines made available developed from a more traditional method such as those developed against diphtheria, mumps, chickenpox or polio
- 69% would be more likely to get a COVID-19 vaccine (primary or booster) if there was an option with fewer side effects
- 65% believe Americans should have more COVID-19 vaccine options to choose from
CovaxinTM is made the same way many childhood vaccines are made and we believe that both the data from clinical trials conducted in India by Bharat Biotech (published online and in peer-reviewed journals) as well as post approval surveillance in India and other countries outside the U.S. suggest CovaxinTM has a favorable safety profile. We are hopeful that CovaxinTM could become an important option in the fight to help end the pandemic and additional data specifically addressing the effectiveness and safety of CovaxinTM in children is coming soon. Our partner Bharat Biotech recently completed a clinical trial of CovaxinTM in more than 500 children and teens aged 2–17 in India with results expected in September 2021 — we plan to release data as soon as it is available. Additionally, Ocugen has submitted the vaccine candidate for expedited review in Canada and we are also planning to conduct several additional clinical trials in the U.S. to support the approval of CovaxinTM . We will continue to work with regulators and the administration to make CovaxinTM available in the U.S. as soon as possible.