NIH-funded adjuvant for COVAXIN COVID-19 vaccine aids India’s pandemic response

The U.S. National Institutes of Health (NIH) reported this week that a COVAXIN adjuvant they funded, Alhydroxiquim-II, is actively aiding the COVID-19 response efforts in India, boosting the COVAXIN vaccine’s efficacy among the millions who have taken it.

Alhydroxiquim-II was originally discovered and tested by biotech company ViroVax LLC, based in Lawrence, Kansas. It was exclusively supported by the National Institute of Allergy and Infectious Diseases (NIAID) Adjuvant Development Program. Comprising a small molecule attached to the substance Alhydrogel, it travels to lymph nodes to activate cellular receptors and bolster immune response to viruses, boosting immune responses and vaccine efficacy.

“Ending a global pandemic requires a global response,” Dr. Anthony Fauci, NIAID director, said. “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.”

Also important for discovery is that Alhydroxiquim-II is the first adjuvant in an authorized vaccine to activate the receptors TLR7 and TLR8 successfully. It also stimulates the immune system to actively search for invading pathogens. In return, it offers only mild side effects.

COVAXIN, which has benefited from the adjuvant, is a COVID-19 vaccine developed and manufactured in India and has been distributed to roughly 25 million people so far. In recent months, the nation has become one of those hardest hit by the ongoing pandemic. The vaccine has demonstrated a 78 percent efficacy against symptomatic disease and full efficacy against severe cases, along with 70 percent efficacy against asymptomatic infection. It also appeared to be effective against the Delta variant currently gaining traction worldwide.

Bharat Biotech International Ltd., which makes COVAXIN, has signed a licensing agreement to use Alhydroxiquim-II for its candidate vaccines. That license was expanded during the pandemic to include COVAXIN.