Pfizer and its German partner BioNTech released a second batch of interim results on Wednesday, saying their coronavirus vaccine candidate is 95 per cent effective and also protects the most vulnerable people in older age groups from the risk of falling prey to the virus.

"Primary efficacy analysis demonstrates BNT162b2 to be 95 per cent effective against Covid-19 beginning 28 days after the first dose; 170 confirmed cases of Covid-19 were evaluated, with 162 observed in the placebo group versus 8 in the vaccine group," the company said.