Bharat Biotech Covaxin efficacy data is substantive and comes from Phase 3 controlled clinical study: Experts

Bharat Biotech Covaxin efficacy data is substantive and comes from Phase 3 controlled clinical study: Experts

Bharat Biotech developed Covaxin in partnership with the National Institute of Virology (NIV), Pune and the Indian Council of Medical Research (ICMR).

By: Shardul Nautiyal
Updated: Nov 13, 2021 11:58 AM

Covaxin Phase 3 trial efficacy and safety study involved 25,800 volunteers across 25 sites in India.

Bharat Biotech Covaxin has an added advantage on its efficacy data which is substantive and comes from Phase 3 trial – controlled clinical study against delta variant. This is unlike other companies which have data against delta variant but more from real world settings, according to experts.

Bharat Biotech’s Covaxin (a whole virion – inactivated vaccine) data was published in one of the prestigious medical journal The Lancet on November 12, highlighting vaccine efficacy of 77.8% efficacy against symptomatic cases and 93.4% against severe symptomatic cases.


“The Lancet peer review confirms the efficacy analysis that demonstrates Covaxin to be effective against Covid-19. Covaxin is the only Covid-19 vaccine to have demonstrated efficacy data from Phase 3 clinical trials against the B.1.617.2 Delta variant at 65.2%,” said Bharat Biotech in a statement following The Lancet published study.


Covaxin Phase 3 trial efficacy and safety study involved 25,800 volunteers across 25 sites in India. Covaxin was well tolerated and the Data Safety Monitoring Board didn’t report any safety concerns related to the vaccine, according to Bharat Biotech.


Bharat Biotech developed Covaxin in partnership with the National Institute of Virology (NIV), Pune and the Indian Council of Medical Research (ICMR).


Substantiating the efficacy of Covaxin, Dr. Krishna Ella, Chairman & Managing Director, Bharat Biotech International Limited, Hyderabad had said in an exclusive interview with Financial Express Online, “In addition to the in-vitro studies of protection we finally got real efficacy data through the clinical trials. One is delta efficacy and the other is asymptomatic population which does not control the viral load. We captured both data points for better efficacy. Bharat Biotech is the only company in the world which has conducted efficacy trial for delta variant when the epidemic was there.”

Globally vaccination drive already took pace since past few months and vaccinated majority of their population at least with 1 dose of vaccine. But point to ponder is do we really know how effective these vaccines are in general against covid-19 and specifically the delta variant.

Covid-19 surge,” according to Mumbai based Independent Pharmaceutical Physician and Researcher Dr. Sujay S Patil.

Pfizer-Biontech vaccine efficacy against Covid-19 was under constant evaluation by different study groups. As per Centre for Controlled Disease (CDC), vaccine was 100% effective in preventing severe disease and 95.3% effective in preventing severe disease as per FDA. Few public health studies conducted for efficacy against severe disease and hospitalization by public Health England had cases of Delta variant but no clear number on delta variant is mentioned.


Moderna vaccine Spikevax efficacy figures similar to Pfizer-Biontech vaccine have changes over time. As per the company, vaccine shows 90% efficacy against symptomatic disease and >95% against severe symptomatic disease. Even though some researchers have highlighted vaccines effectiveness against different variants of Covid-19, but no clear numbers on same are still missing.


Johnson-Johnson vaccine efficacy against has found to be 72% against symptomatic (moderate) disease and 86% for severe symptomatic disease. A real-world study
conducted against delta variant found vaccine efficacy of 71% against hospitalization and up to 95% effective against death.


Oxford-AstraZeneca vaccine Covishield has demonstrated an efficacy of 76% against symptomatic disease and 100% against severe disease. For delta variant, few studies conducted although not peer reviewed have shown vaccine effectiveness of 60 % against symptomatic disease and 93% effective against hospitalization.


According to Phase 3 study data announced in June, Novavax vaccine Covovax had shown 90% efficacy against mild symptomatic disease and 100% efficacy against moderate to severe symptomatic disease as per the company’s statement.


“Novavax vaccine Covovax demonstrated 91.3% efficacy against Covid-19. But efficacy against Delta variant is 60% for symptomatic disease and 93% effective against
hospitalization,” Dr Ishwar Gilada, Consultant in HIV and infectious diseases and Secretary General, Organised Medicine Academic Guild (OMAG) informed.
Novavax is a protein adjuvant vaccination. It’s easier to prepare than some other vaccinations, and it ca n be kept in the fridge, making it easier to distribute. Novavax has successfully tested its vaccine in combination with the influenza vaccination. The vaccination was 91% effective in protecting those in high-risk groups such as those over 65, those with health issues that raise the chance of complications, and those who were pregnant.


“The vaccination is 93% effective against predominantly circulating variants of concern and variations of interest. However, it’s worth noting that the research was conducted in the United States and Mexico, when Alpha was the most common strain in the US, while other varieties were on the rise. To establish the efficiency of Novavax against the Delta strain, more data is needed,” Ahmedabad based Pharmaceutical Consultant Dr. Sanjay Agrawal concluded.