NEW DELHI — After Pfizer and Serum Institute, Hyderabad-based pharmaceutical firm Bharat Biotech applied to the central drug regulator, seeking emergency use authorization for its COVID-19 vaccine Covaxin, official sources said. Covaxin is being indigenously developed by Bharat Biotech in collaboration with the Indian Council of Medical Research (ICMR). The Hyderabad-based firm is conducting phase 3 clinical trials of its vaccine candidate at around 25 sites around the country, including in Delhi, Mumbai, Chennai, Patna and Lucknow. It began its trials in Chennai on Saturday. The SRM Medical College Hospital said the vaccine in the third phase will be tested on about 1,000-1,500 volunteers The firm, while applying for the phase-3 trial, had stated that the vaccine was well-tolerated in all dose groups and no serious adverse events have been reported. The most common adverse event was transient pain at the injection site, a source said. The Drugs Controller General of India (DCGI) had on Oct. 23 granted permission to the firm for conducting phase-3 clinical trial of Covaxin after assessing the safety and immunogenicity data of phase 1 and 2 trials. The Serum Institute of India became the first indigenous company to apply to the Drugs Controller General of India (DCGI) seeking emergency use authorization for the Oxford COVID-19 vaccine in the country citing unmet medical needs due to the pandemic and in the interest of the public at large. An expert committee of the Central Drugs Standard Control Organization (CDSCO) will meet to review applications of Pfizer, Serum Institute of India and Bharat Biotech seeking emergency use authorization for their COVID-19 vaccine candidates. At an all-party meeting on Dec. 4, Prime Minister Narendra Modi had expressed hope that a COVID-19 vaccine may be ready in a few weeks. That evening, the Indian arm of US pharmaceutical giant Pfizer had sought approval for its vaccine from the central drug regulator, after the firm secured such clearance in the UK and Bahrain. The Serum Institute sought the nod for the Oxford COVID-19 vaccine, Covishield, on Dec. 6. — Agencies