The coronavirus vaccine from Pfizer – which is due to arrive in the UK before the end of the year – is 95% effective and has passed its safety checks, according to further data from the firm.
The pharmaceutical giant and its partner BioNTech published interim results last week showing the jab could prevent more than 90% of people developing Covid-19.
That data were based on the first 94 volunteers to develop Covid-19, but further figures released on Wednesday are based on the first 170 cases of the virus in the clinical trial.
The vaccine has been tested on 43,500 people in six countries and no safety concerns have been raised.
The UK has secured 40m doses in total of the vaccine, with 10m due in the country by the end of the year if it is approved.
People will need two doses, meaning enough vaccine has only been secured for 20m Brits.
Another jab, from US firm Moderna, was shown this week in early data to be almost 95% effective.
The UK has ordered five million doses of that jab, enough for 2.5m people, and is keenly awaiting the results of the Oxford University and AstraZeneca vaccine study – which is due to report soon. The government has ordered 100m doses of that vaccine.
Changes to the Human Medicine Regulations announced in October will allow the Medicines and Healthcare Products Regulatory Agency (MHRA) to authorise temporary supply of vaccines, if one becomes available before 2021.
This means that if a vaccine is found to meet the safety, quality and effectiveness standards by the agency then vaccinations can begin without needing to wait for the European Medicines Agency as would normally need to happen.
Health secretary Matt Hancock has said the NHS will be ready by December 1 to roll out any jab.
The Pfizer vaccine has been shown to produce both an antibody and T-cell response in the body to fight coronavirus.
Pfizer and BioNTech expect to be able to produce up to 50m vaccine doses globally in 2020 and up to 1.3bn in 2021.
They will have to come to Britain from the company’s distribution centre in Belgium, and need to be stored at minus 70C.
The moment the vaccine leaves the factory, it can only be taken out of minus 70C four times before it is injected into a patient’s arm. But it can be stored at a warmer temperature in the two days prior to being used, implying that the vaccine will be able to be administered two days after deliveries without the need for new refrigeration systems.
Hancock said he has “confidence” the NHS can deliver an approved vaccine despite the logistics involved.
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