Phase-3 trial of Covaxin began at Sola Civil Hospital in Gujarat's Ahmedabad.
Volunteers are coming at the hospital for the test.
"Volunteers who've been vaccinated have yet not complained of any health issues or symptoms. More volunteers will be vaccinated today," said Sola Civil Hospital Medical Superintendent Dr Parul Bhatt.
Meanwhile, preparation is underway at Serum Institute of India in Pune where Prime Minister Narendra Modi is scheduled to visit on November 28.
PM will review the vaccine production.