The first batches of Covaxin, the Bharat Biotech's coronavirus vaccine, left Hyderabad early this morning for Delhi and 10 other cities, a day after Serum Institute of India rolled out its vaccine against COVID-19 ahead of the nationwide inoculation drive on Saturday which officials say will be the 'world's biggest'. The first consignment, which reportedly included three boxes weighing 80.5 kg, was flown to Delhi by Air India.