An experimental antibody treatment designed to stop people developing Covid-19 after being exposed to the virus has failed clinical trials, dealing a blow to Britain's hopes that it could soon have a new weapon to fight coronavirus.
Anglo-Swedish drugmaker AstraZeneca gave an antibody drug to unvaccinated adults who had been exposed to Covid-19 within the past eight days.
Antibody treatments are meant to work by pumping patients with antibodies to boost their immune system and stop them from developing a virus after they have come into contact with it.
However AstraZeneca said its drug reduced the risk of developing symptomatic Covid-19 by around a third compared to a placebo, which was "not statistically significant".
The drug had been touted as offering a potential treatment for those who had already contracted Covid-19 or for those who could not be vaccinated. It was announced as a key pillar of the Government's fight against Covid-19 last summer, at which point it said it was striking a deal for one million doses of the AstraZeneca treatment.
Last July, the Government said those who could not be vaccinated included people suffering from cancer, although NHS advice is now that people living with cancer should get the vaccine. Some people with severe allergies are still advised against a Covid jab.
When the trial for the treatment kicked off in November, Business Secretary Alok Sharma said: "I am very proud that the UK is the first country in the world to begin this invaluable study, and that a fifth of trial volunteers will be from Britain – a testament to our fantastic life sciences sector and the willingness of our people to come forward to help others."
In recent weeks however reports had suggested the UK was considering pulling out of the AstraZeneca deal, which had been a non-binding agreement and had been dependent on the treatment working. Vaccinations have accelerated in recent weeks, and NHS boss Simon Stevens said he expected all adults in England to be offered a jab by the end of the week.
Meanwhile, Mr Stevens has said the NHS is hoping to be able to offer radical antibody cocktails to patients, being developed by other companies including Regeneron Pharmaceuticals. He has urged healthcare services to "gear up" for a rollout. The treatments could be given the green light by this summer.
AstraZeneca's candidate had also been seen as a leading option by the US government which struck a deal for up to 700,000 of the treatment. AstraZeneca said it was now in talks with officials regarding the next step on that deal.
Mene Pangalos, the executive vice president of AstraZeneca, said: "While this trial did not meet the primary endpoint against symptomatic illness, we are encouraged by the protection seen in the PCR negative participants following treatment with AZD7442."
A Department of Health and Social Care spokesman said: “To end this pandemic and send this virus into retreat, we have taken a broad approach, including the possible use of antibody treatments.
“The phenomenal pace of the UK’s vaccination programme has allowed us to refine our approach to possible antibody treatments and we are investigating several, including through a network of national platform trials. These trials have already made crucial breakthroughs including monoclonal antibodies tocilizumab and sarilumab, both of which have now been rolled out to NHS patients.
“The government will continue to work closely with manufacturers to ensure that UK patients have access to a range of Covid-19 therapeutics as evidence of efficacy continues to emerge.”