The United States National Institute of Health (NIH) has said India’s Covid-19 vaccine Covaxin effectively neutralises both Alpha and Delta variants of coronavirus.
The results of two studies of blood serum from the people, who had received Covaxin, suggest the vaccine generates antibodies that effectively neutralise the B.1.1.7 (Alpha) and B.1.617 (Delta) variants of SARS-CoV-2, first identified in the UK and India respectively, said the NIH.
The NIH, which has a strong scientific collaboration with India, said that an adjuvant developed with funding from it has contributed to the success of the highly efficacious Covaxin.
The NIH said Covaxin - developed by Hyderabad-based pharmaceutical company Bharat Biotech in collaboration with the Indian Council of Medical Research - comprises a disabled form of SARS-CoV-2 that cannot replicate but still stimulates the immune system to make antibodies against the virus.
Stating the published results from a phase 2 trial of the vaccine indicate it is safe and well-tolerated, the top U.S. health research institute added that safety data from a phase 3 trial of Covaxin will become available later this year.
Meanwhile, unpublished interim results from the phase 3 trial indicate that the vaccine has 78 percent efficacy against symptomatic disease, 100 percent efficacy against severe COVID-19, including hospitalisation, and 70 percent efficacy against asymptomatic infection with SARS-CoV-2, the virus that causes Covid-19, PTI reported the NIH as saying.
The NIH further said the results from two studies of blood serum from the people, who had received Covaxin, suggest that the vaccine generates antibodies that effectively neutralise the B.1.1.7 (Alpha) and B.1.617 (Delta) variants of SARS-CoV-2, first identified in the UK and India respectively.
Meanwhile, National Institute of Allergy and Infectious Diseases (NIAID) Director Anthony S. Fauci said ending a global pandemic requires a global response.
Fauci expressed his pleasure that a novel vaccine adjuvant developed in the US with NIAID - part of NIH - support is part of an efficacious Covid-19 vaccine available to the people in India.
Alhydroxiquim-II, the adjuvant used in Covaxin, was discovered and tested in a laboratory by biotech company ViroVax LLC of Lawrence, Kansas, with the NIAID Adjuvant Development Program’s support.
Alhydroxiquim-II is the first adjuvant in an authorised vaccine against infectious disease to activate receptors TLR7 and TLR8 that play a vital role in the immune response to viruses.
The alum in Alhydroxiquim-II stimulates the immune system to search for an invading pathogen.
The NIH said the molecules that activate TLR receptors stimulate the immune system powerfully, but the side effects of Alhydroxiquim-II are mild.
The NIAID Adjuvant Program has supported the research of the founder and chief executive officer of ViroVax, Dr Sunil David, M.D., Ph.D., since 2009, the NIH added.
The collaboration between Dr David and Bharat Biotech was initiated during a 2019 meeting in India coordinated by the NIAID Office of Global Research under the auspices of NIAID's Indo-US Vaccine Action Program.
Bharat Biotech signed a licensing agreement with Dr David to use Alhydroxiquim-II in their candidate vaccines.
This license was expanded during the Covid pandemic to include Covaxin, which has received Emergency Use Authorisation in India and several other nations.
Stating the company conducted extensive safety studies of Alhydroxiquim-II and undertook the complex process of scaling up production of the adjuvant under Good Manufacturing Practice standards, the NIH said Bharat Biotech expects to produce an estimated 700 million doses of Covaxin by this year-end.
(With PTI Inputs)