Pfizer/BioNTech today (Monday 9 November) published positive efficacy results from Phase 3 studies of their potential Covid-19 vaccine, showing it to be more than 90% effective in preventing coronavirus in participants.A government spokesperson said: Read Pfizer’s full announcement. The results from Pfizer/BioNTech are very promising and we have procured 40 million doses of their vaccine. While we are optimistic of a breakthrough, we must remember that there are no guarantees. We will know whether the vaccine meets robust standards of safety and effectiveness once the safety data have been published, and only then can the medicines regulator consider whether it can be made available to the public. Once approved, the NHS stands ready to begin a vaccination programme for those most at risk, as currently recommended by the independent Joint Committee on Vaccination and Immunisation (JCVI), before being rolled out more widely.