Controversy around Bharat Biotech's Covaxin approval without efficacy data

On a day when Bharat Biotech's Covaxin, an indigenously developed Covid19 vaccine got a nod from the country's regulator, on the grounds that it may offer protection against the mutated strain of Sars-CoV-2 from the UK, experts did raise some doubts about the logic behind the approval. A controversy erupted around the approval with political leaders taking to social media to express their opinion. 

Bharat Biotech's Covaxin is based on a whole inactivated virus platform, an old technology which is used to make vaccines given to infants. Theoretically, such vaccines (based on a whole virus) can work against different variants