Pfizer to know next month if potential Covid-19 vaccine works

US drug giant Pfizer has said it should know by the end of October whether a Covid-19 vaccine it is developing is successful, and will submit it for approval immediately if that is the case.

Pfizer had enrolled 23,000 patients in vaccine tests as of Wednesday, its chief executive Albert Bourla said in an online briefing sponsored by drug industry group International Federation of Pharmaceuticals Manufacturers and Association.