What is the Recovery trial and why are its findings thought to be so important?
Recovery, based at Oxford University, is the biggest randomised controlled trial of drugs against Covid-19 in the world, thanks in no small part to the NHS. Almost all acute hospitals across the whole of the UK – 176 in all – have enrolled sick patients. There are more than 11,500 patients taking part so far.
The trial has been testing six different treatments against the normal standard of care – which in Covid-19 means mostly oxygen support. Patients are randomly allocated to receive one of the drugs. A data safety monitoring committee has access to the outcome data and regularly looks to see how things are going. If there were extremely poor or extremely good results for any drug, they would stop the trial. Otherwise it continues until enough people have been treated to be sure of the outcome. Randomised controlled trials such as this are considered the “gold standard”. Following the breakthrough with dexamethasone, the NHS made it clear that the drug would be made available to all patients who might be helped by it.
What has it found out so far?
The big news is that low doses of the steroid drug dexamethasone save lives. This was one of the first drugs to be included in the trial, because it has been used in the past against inflammatory conditions, including in the lungs, and it is cheap and readily available for use. Although trials during Sars came up with mixed results, in the Recovery trial, where very low doses were used, it cut deaths among the sickest people, on ventilators, by up to a third. One in eight people survived thanks to the drug. Among those who needed oxygen support but not a ventilator, it was one in five. It did not help those who could breathe unaided.
Any other results?
It may have settled the controversial question of the use of the antimalarial drug hydroxychloroquine in hospitalised Covid-19 patients. Basically, the drug did not work. That arm of the trial was stopped by the data safety committee because it was clear that hydroxychloroquine, favoured by Donald Trump, was no better than a placebo. But the drug may still have a use in preventing infection, which was the reason Trump said he took it – there are other trials investigating that.
What other drugs are being trialled in Recovery?
The HIV drug combination lopinavir/ritonavir, known by the brand name Kaletra, is also in the trial. So is Azithromycin, which is a commonly used antibiotic and has been given to some patients in France alongside hydroxychloroquine. The newest drug added to the trial is Tocilizumab, an anti-inflammatory treatment given by injection. The results of these arms will be announced as soon as the data is sufficient to prove unequivocally that they work or do not.
Any other treatments?
Convalescent plasma is also being tested. This is from blood donated by patients who have recovered from Covid-19 and will contain antibodies that their immune systems have generated against the virus.