COVID-19 : Pfizer-BioNTech’s vaccine found 90% effective in phase 3 trial

New Delhi:  An experimental vaccine jointly developed by Pfizer and BioNTech was found to be 90 per cent effective in preventing the disease in the ongoing phase 3 trials that have enrolled nearly 44,000 people in the US and five other countries, the companies said on Monday. It may be noted that the finding was the result of the first independent analysis of any coronavirus vaccine candidate currently in phase 3 trials. The companies plan to submit data from the full phase 3 trial for scientific peer-review publication.

Preliminary findings from the phase 3 trial showed that 94 participants who got the two-dose vaccine were protected against the virus, 28 days after their first shot.

“The first set of results from our phase 3 Covid-19 vaccine trial provides the initial evidence of our vaccine’s ability to prevent COVID-19,” Pfizer chairman and CEO Albert Bourla said in a statement, AFP reported.

According to the World Health Organization (WHO), no vaccine is 100 per cent effective. The US Food and Drug Administration’s criteria for approving a Covid-19 vaccine noted that a COVID-19 vaccine should show at least 50 per cent efficacy in phase 3 trials, the final stage before commercial licensing, for it to be widely deployed.

Recently, Bourla had said that the US drug giant could supply some 40 million doses in the United States in 2020, if clinical testing proceeds as expected and regulators approve a vaccine.

Pfizer said it is gathering two months of safety data following the final dose, which is a requirement of the FDA, to qualify for EUA, which it expects by the third week in November.

“We look forward to sharing additional efficacy and safety data generated from thousands of participants in the coming weeks,” Bourla added.

While the Pfizer-BioNTech’s vaccine results are yet to be peer-reviewed by experts, scientists reacted positively – if cautiously to the findings.

Michael Head, Senior Research Fellow in Global Health, University of Southampton, called it an “excellent result for a first generation vaccine”.

Peter Horby, Professor of Emerging Infectious Diseases and Global Health in the Nuffield Department of Medicine, University of Oxford, said Pfizer’s announcement ‘feels to me like a watershed moment’ in the pandemic.

However, others pointed out that there would likely be significant logistical problems in getting the vaccine to everyone, especially given it must be kept super-cooled and currently requires two doses to bestow immunity, the AFP report added.

“If a vaccine is to reduce severe disease and death, and thus enable the population at large to return to their normal day-to-day lives, it will need to be effective in older and elderly members of our society,” she said.

The shots made by Pfizer and BioNTech are among 10 possible vaccine candidates in late-stage trials being conducted around the world. Meanwhile, Moderna Inc, another US company has said it hopes to be able to file an application with the FDA later this month. The coronavirus pandemic has so far killed at least 1,255,803 people all over the world.