“The firm has to submit safety data, evaluated by the Data Safety Monitoring Board (DSMB), to the CDSCO before proceeding to phase 3 clinical trials,” a senior official said. “As per the study design, each subject will be administered two doses four weeks apart (first dose on day one and second dose on day 29) following which the safety and immunogenicity will be assessed at predefined intervals,” the official said.

Currently, phase 2 and 3 clinical trials of the Oxford vaccine candidate is going on in the United Kingdom, phase 3 clinical trial in Brazil and phase 1 and 2 clinical trials in South Africa. The officials said that the SII had submitted a revised proposal on Wednesday after the expert panel on Tuesday, following deliberation over its application, had asked it to revise its protocol for the phase 2 and 3 clinical trials besides seeking some additional information.

The panel has also recommended that the clinical trial sites which have been proposed for the study be distributed across India.

According to the revised proposal, 1,600 people aged above 18 years will participate in the trials across 17 selected sites, including AIIMS Delhi, BJ Medical College in Pune, Rajendra Memorial Research Institute of Medical Sciences (RMRIMS) in Patna, Post Graduate Institute of Medical Education and Research in Chandigarh, AIIMS-Jodhpur, Nehru Hospital in Gorakhpur, Andhra Medical College in Visakhapatnam and JSS Academy of Higher Education and Research in Mysore.

“According to the application, it would conduct an observer-blind, randomised controlled study to determine the safety and immunogenicity of ‘Covishield’ on healthy Indian adults,” the official said.

The SII, which has partnered with AstraZeneca, for manufacturing the Oxford vaccine candidate for COVID-19 had submitted its first application to the DCGI on July 25 seeking permission for conducting the phase 2 and 3 trials of the potential vaccine.