In an urgent situation like the Covid pandemic, the drug regulator has the authority to give approval for restricted use to a vaccine based on its safety and immunogenicity data from phase 1 and 2 studies while phase 3 clinical trial is under way, Indian Council of Medical Research (ICMR) chief Balram Bhargava said on Tuesday. In an urgent situation like the Covid pandemic, the drug regulator has the authority to give approval for restricted use to a vaccine based on its safety and immunogenicity data from phase 1 and 2 studies while phase 3 clinical trial is under way, Indian Council of Medical Research (ICMR) chief Balram Bhargava said on Tuesday.