More than 20,000 people are to take part in a first-of-its-kind clinical trial to investigate new oral coronavirus antiviral treatments that can be taken at home.
The study, which is recruiting now, will quickly assess the effectiveness of a range of purpose-designed Covid-19 antivirals.
The new drugs are intended for use in the early stages of infection by people with the virus who are at higher risk of complications from the disease.
The platform adaptive trial of novel antivirals for early treatment of Covid-19 In the community is run by the University of Oxford in collaboration with GP hubs.
It comes as the UK embarks on a huge booster vaccine programme after the emergence of Omicron.
The UK Antiviral Taskforce selected the treatments to be tested, and the first to be investigated will be molnupiravir, a Covid antiviral pill already licensed by the the Medicines and Healthcare products Regulatory Agency (MHRA).
People can join the study if they have tested positive for the virus, are within five days of the onset of symptoms – and are aged 50 and over.
Or if they are between 18 and 49 with underlying health conditions that make them clinically more vulnerable. All participants should have recorded a positive PCR test within the past seven days.
The study will enrol 10,600 volunteers for each arm of the study.
To enable the benefit of the treatment to be compared against standard care, half of them will be randomly allocated to receive the antiviral treatment plus standard care.
The other half will receive standard care alone.
Results from the national study will enable the NHS to better plan how to make Covid-19 antivirals available for those who would most benefit from them.
Eddie Gray, chairman of the taskforce, said: “We want to ensure that a wide number of people are conscious and aware that if they get symptoms and a positive test, they qualify and for them to move quickly into that system.
“I think if they can do that, then there’s an awful lot of benefit to be gained both for those individual patients and for the UK healthcare system.”
He said: “I think it gives us a real mechanism for managing patients in what is an extremely high pressure time for frontline staff in the National Health Service.
“But for us to do that, we need the active engagement of the potential patients.”
He said he expected Merck's molnupiravir and Pfizer's paxlovid treatments to be available throughout the winter period, which he defined as between now and the end of March. Britain has yet to approve paxlovid.