The Pfizer/BioNTech Covid vaccine, which has an efficacy of almost 95%, has been authorised by the UK medicines regulator, making the UK the first western country to license a vaccine against the disease. The UK has 40m doses of this vaccine on order.
Remind me how this vaccine works …
The Pfizer/BioNTech Covid jab is an mRNA vaccine – a cutting-edge technology. The vaccine works by introducing into the body genetic material, called mRNA, that contains the instructions to make the so-called “spike” protein of the coronavirus.
In response to these proteins, the body’s immune pathways are activated – a response that offers protection should we encounter the virus itself.
Where is this vaccine manufactured?
The vaccine itself is manufactured at Pfizer plants in the US and Europe. Stocks for the UK will come from the company’s site in Puurs, Belgium, which has already begun churning out thousands of doses. This site will also act as a back up for the company’s site in Kalamazoo, Michigan to support supply in the US.
BioNTech also has production sites in Mainz and Idar-Oberstein, Germany, for commercial supply of the vaccine, with a third site in Germany set to start manufacturing in 2021.
How is it going to be stored and transported?
The Pfizer/BioNTech vaccine, while exciting, brings logistical challenges. Among them, the vaccine must be stored and transported at about -70C.
To keep the vaccine at the required ultra-low temperature, the doses will be packaged with solid carbon dioxide and placed in reusable containers that resemble pizza boxes for shipping. Pfizer said that, unopened, these boxes keep the vaccine at the correct temperature for 10 days.
Once in the UK, the vaccine will be transported to vaccination centres – there they can be stored in regular medical refrigerators at 2C-8C for up to five days, or the shipping boxes can be topped up with dry ice every five days allowing the vaccine to be stored for up to 30 days.
The temperature of the vaccine will be carefully monitored at each stage of transport to ensure the doses do not become unstable and ineffective. However Pfizer has said the vaccine will be shipped on a “just in time” basis, meaning frozen doses are rapidly delivered to vaccination centres as needed.
Who will get the vaccine first?
Matt Hancock, the health secretary, has said he expects 10m doses of the Pfizer/BioNTech vaccine to be available in 2020: the NHS has been told to prepare for the first doses to be given as early as next week.
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While the government’s Joint Committee on Vaccination and Immunisation (JCVI) put care home residents and care home workers at the front of the queue for a Covid vaccine, it is likely that NHS staff will be the first group to receive the Pfizer/BioNTech jab.
NHS officials say the decision is pragmatic and based upon the characteristics of the vaccine, with limits on the number of times it can be moved, and its shelf life making it unsuitable for use in out-of-hospital settings.
What about the other Covid vaccines?
Both the Moderna mRNA vaccine, and the Oxford University/AstraZeneca vaccine (which uses a harmless chimp cold virus to deliver genetic information from the coronavirus to human cells) have released phase 3 clinical trial results and are under review by the MHRA.
These jabs are also part of the UK government’s portfolio of potential Covid vaccine candidates, with 7m doses of the Moderna vaccine and 100m doses of the Oxford University/AstraZeneca vaccine already secured.
These vaccines have a key advantage over the Pfizer/BioNTech jab – they do not need to be kept at -70C. Indeed the Moderna vaccine can be stored at -20C and is stable for up to 30 days at temperatures between 2C and 8C, while the Oxford University/AstraZeneca vaccine can be stored between 2C and 8C for at least six months. That makes these vaccines easier to distribute to places such as care homes, prisons and patients’ homes.
How will these vaccines be distributed to the population?
There are several routes by which the vaccines will be distributed.
The first is via 1,560 community-based vaccination centres run by GPs, which will each dispense 200 to 500 jabs a day. In addition, some vaccines will be sent to hospitals to be administered to staff, while there are also plans for mobile inoculation units.
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Mass vaccination centres are also in the process of being set up, with the NHS planning to use large venues such as football stadiums and conference buildings for the purpose. In Bristol, the military have been working to turn the Ashton Gate stadium into a vaccination centre, while it is thought the Cheltenham racecourse could follow suit. Such centres are expected to vaccinated up to 5,000 people a day.
Which vaccine will be distributed at each centre is unclear, but given the cold chain requirements of the Pfizer/BioNTech jab, it is unlikely this will be used at the mass vaccination centres or by mobile inoculation units. Instead, the Oxford University/AstraZeneca vaccine, once approved, is likely to be the backbone of the UK’s mass vaccination programme.
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