Fauci’s institute backs Covaxin, funded its efficacy booster

Covaxin is one of the two most popular Covid-19 vaccines in India, alongside AstraZeneca’s Covishield. Though results of Phase 3 clinical trials are awaited, it has been given emergency use authorisation.

A top US infectious diseases institute on Tuesday said it funded research that led to the development of a chemical substance that boosts the efficacy of Bharat Biotech’s Covid-19 vaccine, Covaxin, which, studies have suggested, can effectively neutralise the Alpha and Delta variants of SARS-CoV-2.

The adjuvant used in Covaxin - Alhydroxiquim-II - has been developed by ViroVax of Lawrence, Kansas, a company founded and run by Indian-American Sunil David.

The US National Institute of Allergy and Infectious Diseases (NIAID) said the project was exclusively supported and funded by its adjuvant development programme. “Ending a global pandemic requires a global response,” said Anthony Fauci, the NIAID director, and added, throwing the institute’s weight behind the vaccine, “I am pleased that a novel vaccine adjuvant developed in the United States with NIAID support is part of an efficacious Covid-19 vaccine available to people in India.”

David had been working with the NIAID Adjuvant Program since 2009, since he founded the company after 20 years of research and teaching on the faculty of the University of Kansas and University of Minnesota. He has focused on “searching for novel molecules that activate innate immune receptors and developing them as vaccine adjuvants”.

David went to Christian Medical College in Vellore and came to the US after postdoctoral training stints at Borstel, Germany, and the Indian Institute of Science, Bangalore.

Covaxin is one of the two most popular Covid-19 vaccines in India, alongside AstraZeneca’s Covishield. Though results of Phase 3 clinical trials are awaited, it has been given emergency use authorisation in India.

NIAID gave the vaccine its backing - drugs are authorised and regulated by the US Food and Drug Administration - saying, “Unpublished interim results from the Phase 3 trial indicate that the vaccine has 78% efficacy against symptomatic disease, 100% efficacy against severe Covid-19, including hospitalisation, and 70% efficacy against asymptomatic infection with SARS-CoV-2, the virus that causes Covid-19.”

The institute also cited two studies that Covaxin generates antibodies that “effectively neutralise” both Alpha and Delta variants of SARS-CoV-2.

Here is how this adjuvant works, according to NIAID: “The adjuvant comprises a small molecule attached in a unique way to Alhydrogel, a substance frequently called alum that is the most commonly used adjuvant in vaccines for people. Alhydroxiquim-II travels to lymph nodes, where the small molecule detaches from alum and activates two cellular receptors. These receptors, TLR7 and TLR8, play a vital role in the immune response to viruses.”

Bharat Biotech signed a licensing agreement with ViroVax in 2019 for some of its candidate vaccines - also arranged by NIAID under the Indo-US Vaccine Action Program - and expanded the licence to include its use in the Covid-19 vaccine after the breakout of the epidemic.

By Yashwant Raj I Edited by Amit Chanda

UPDATED ON JUN 30, 2021 10:41 AM IST