Two doses of Covaxin are 50 percent effective against symptomatic Covid-19, according to the first real-world assessment of India's indigenous coronavirus vaccine published in The Lancet Infectious Diseases journal. The results of an interim study recently published in The Lancet showed that two doses of Covaxin, also known as BBV152, had 77.8 per cent efficacy against symptomatic disease and present no serious safety concerns. The latest study assessed 2,714 hospital workers at the All India Institute of Medical Sciences (AIIMS) in Delhi, from April 15¿May 15, who were symptomatic and underwent RT-PCR test for Covid-19 detection.

Researchers noted that the Delta variant was the dominant strain in India during the study period, accounting for approximately 80 per cent of all confirmed Covid-19 cases. Covaxin, developed by Hyderabad-based Bharat Biotech in collaboration with the National Institute of Virology, Indian Council of Medical Research (NIV-ICMR), Pune, is an inactivated whole virus vaccine administered in a two-dose regimen, 28 days apart. In January this year, Covaxin was approved for emergency use in India for people aged 18 and above. The World Health Organization (WHO) added the vaccine to its list of approved emergency use Covid-19 vaccines earlier this month.