Pfizer says Covid-19 vaccine 90% effective

Pfizer and BioNTech said their Covid-19 vaccine candidate prevented more than 90% of infections in a study of tens of thousands of volunteers, paving the way for emergency use.

Pfizer said the findings were based on analysis conducted after 94 participants given the two-dose vaccine were protected against the disease 28 days after the first dose. The trial will continue until 164 cases occur.

If the success rate holds up and safety results are positive the companies will apply to the US Food and Drug Administration for emergency use authorisation. Pfizer said no serious safety concerns had been observed in the study of 43,538 participants.

Albert Bourla, Pfizer's chairman and chief executive, said: "Today is a great day for science and humanity. The first set of results from our Phase 3 Covid-19 vaccine trial provides the initial evidence of our vaccine’s ability to prevent Covid-19."

Pfizer shares rose 11.6% to $40.64 in premarket trading. The FTSE 100 jumped 4.8% to 6,196 in response to the best news about Covid-19 since the pandemic was declared in March.

The results are well ahead of the FDA's standard for approving a Covid-19 vaccine and are the biggest step towards developing a vaccine from various projects around the world. No vaccine is foolproof and the FDA's requirement for a coronavirus vaccine is at least 50%.

Pfizer and Germany's BioNTech said they could manufacture up to 50m doses in 2020 and 1.3bn more in 2021. The US has snapped up 100m doses with an option for 500m more and the UK has an agreement for 30m with the EU in talks about securing 200m.

The news marks rapid progress by drug companies in response to the worst pandemic for 100 years, which has killed 1.2m people and forced governments to provide unprecedented support to prevent economic collapse. Infection rates are rising again after lockdowns in the spring partly suppressed the virus.

Nikesh Patel, head of investment strategy at Kempen Capital Management, said: "This is the first news that lets governments start planning ahead to when economies can properly start to reopen from lockdowns. This is great news as it allows governments to make that fiscal response without fears of endless support."

Bourla said: "We are a significant step closer to providing people around the world with a much-needed breakthrough to help bring an end to this global health crisis. We look forward to sharing additional efficacy and safety data generated from thousands of participants in the coming weeks.”