Will the vaccine be ready by Christmas?
Those who are categorised as the highest priority may receive the Pfizer vaccine before Christmas, according to a deputy chief medical officer in Downing Street.
At the press conference on November 9th, Prof Van-Tam declared he was “hopeful we could see some vaccine by Christmas”. However, he encouraged the public not to “get too over-excited about where we are” before the Prime Minister also emphasised this breakthrough was still in its ‘very early stages’.
The NHS has been instructed to prepare for mass Covid-19 vaccination of the public from December 1, with plans to dispense 1,000 jabs a week at 1,500 GP practices and drive-through centres.
Medical and nursing students, and retired medics, are being drafted in to help. Chair of the Royal College of General Practitioners, Prof Martin Marshall, suggested dentists should join them to allow other treatments to continue.
Other vaccine trials are under way…
The latest data in the Oxford University trials shows that their vaccine produces a “strong” immune response among the elderly. Analysis of the Phase II stage of the trial process reportedly found similar responses across all age groups, in findings that have been hailed as a “milestone” in the fight against the pandemic.
As well as several Phase 3 trials taking place on vaccine candidates around the world, the UK is starting some “human challenge trials”, where volunteers are exposed to the virus as part of testing the vaccines.
The Imperial human challenge trial is being run by hVivo, a spin-off company from Queen Mary University of London. Already roughly 2,000 people have signed up to take part in challenge studies in Britain through the group 1Day Sooner.
Those testing the vaccine will be given the jab and will then wait a month for antibodies to build. The volunteers will then be exposed to the virus.
Currently, vaccines are tested at population level, so scientists look to see whether a smaller percentage of people are infected than would be expected in the vaccine arm of the trial compared to a control group.
However worldwide lockdowns have meant that virus in the community has been very low in recent months, and scientists have struggled to get enough data to know whether their vaccines are working.
Oxford University has been forced to move some of its vaccine testing to South America and South Africa, although it is expecting results back soon.
What’s the latest on Oxford?
Oxford’s vaccine trial was halted on September 8 after a participant in the UK had an adverse reaction.
The vaccine, developed with AstraZeneca, cleared phases one and two human trials and progressed to the third phase where it was being tested on a larger number of participants.
But the adverse reaction experienced by the participant in the vaccine trial may not have been caused by the experimental vaccine itself, it has since been claimed. One participant died during trials in Brazil, but trials have continued as the death is understood not to be linked to the trial.
Oxford announced on September 12 that clinical trials of its coronavirus vaccine will resume in the UK. And on October 23, it was announced that human trials of the Oxford and AstraZeneca coronavirus vaccine have also resumed in the US.
Before that, testing had been positive. The full results of the Oxford trials, published on July 20, showed that initial trials on 1,077 British adults found that the vaccine induced strong antibody and T-cell responses, which may improve further after a booster jab.
The discovery is promising because separate studies have suggested that antibodies may fade away within months while T-cells can stay in circulation for years.
The Oxford jab works like a traditional vaccine. The spike protein of the coronavirus, which helps it attach to human cells, is inserted into a common cold virus. The immune system detects the invaders and produces T-cells and antibodies to fight them, preparing the body for an attack by the real virus.
This method is cheaper than that of the Pfizer vaccine. The latter sends a piece of genetic code into human cells instructing them to make the spike protein themselves. No vaccine has ever been successfully created in this way before. Novelty is expensive, and so is the fact that, relying on a live piece of genetic code, the Pfizer vaccine must be kept at minus 70 degrees Celsius.