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US ‘failures’ are holding back search for coronavirus drugs

<span>Photograph: John Cairns/AP</span>
Photograph: John Cairns/AP

The global effort to produce useful anti-Covid medicines is being hampered by the US because researchers are testing drugs in “an arbitrary, willy-nilly way”, the expert leading the UK’s programme has warned.

Britain’s Recovery Trial programme, which has involved 12,000 patients at several hundred British hospitals, has already pinpointed one promising new drug to tackle the disease and also highlighted two others – previously thought to be potential life-savers – as being useless.

But the failure of the US medical system to match this output has meant that other promising treatments that could have been cleared for widespread use have still to be evaluated. In particular, convalescent plasma (blood plasma that is taken from Covid-19 patients and which contains antibodies that could protect others against the disease) has still to be properly tested on a large-scale randomised trial.

“Tens of thousands of people have already been given convalescent plasma in the US but these treatments were not randomised,” said Professor Martin Landray, one of the founders of the Recovery programme. “They just give individuals convalescent plasma in the hope it will work. Vast quantities have been given and they still have no idea whether it helps or harms or has no impact,” added Landray, an expert in the setting up of large-scale drug trials.

The US is failing to do large, randomised trials and that ends up providing bad medicine

Professor Martin Landray

Randomised drug trials are the gold standard for pinpointing useful medicines. They remove unconscious biases that might cloud clinicians’ judgments. Thousands of people are given a drug and thousands of others are given a placebo. No one knows which they have been given. Then results are compared and the efficacy of the treatment revealed.

In this way, Recovery was able to demonstrate that the steroid dexamethasone reduced deaths by a third in Covid-19 patients on ventilators. It also showed that the much-hyped drug hydroxychloroquine – as well as the combined therapy of the drugs lopinavir and ritonavir – had no effect in saving patients’ lives.

Crucially these trials needed very large numbers of patients and no single hospital has enough for such research. Britain has had one key advantage – a centralised National Health Service. By contrast, the US health service is fragmented and its only success in pointing a possible treatment has been highlighting the usefulness of the highly expensive drug remdesivir for speeding recovery of some Covid-19 patients.

“There are lots and lots of small drugs trials involving a few dozen or a few hundred patients going on in the US but nothing of any substance,” added Landray. “They are failing to do large, randomised trials and that ends up providing bad medicine. It makes the practice of medicine poorer and the outcomes for patients poorer.”

Related: Coronavirus vaccine: Oxford team aim to start lab-controlled human trial soon

Landray said this failure was particularly exasperating when it came to the use of convalescent plasma, which many doctors believe could have a key role to play in treating seriously ill Covid-19 patients. “If you look at the US, huge quantities of this treatment have been used on an arbitrary willy-nilly basis. The UK excels beyond measure compared with what’s going on there,” he added.

Professor Peter Horby, an expert on infectious diseases and the other founder of the Recovery programme, said: “There have been reports of 20,000 patients getting convalescent plasma in a cohort but none of those patients were randomised. If they had put these patients into randomised trials, we would now have a clear answer about the effectiveness of convalescent plasma.”

Horby added that UK Recovery has now launched a randomised trial of convalescent plasma but does not expect results to be ready until later this year.