Coronavirus cure: Ebola drug has 'clear cut' benefit, says US's Dr Fauci

The drug appears to speed recovery time by 30 per cent but the impact on mortality was too small to claim a benefit

National Institute of Allergy and Infectious Diseases Director Dr Anthony Fauci attends a coronavirus response meeting between US President Donald Trump and Louisiana Governor John Bel Edwards in the Show more

The top US epidemiologist says antiviral medicine remdesivir has a "clear cut" benefit in the treatment of Covid-19, after a clinical trial showed patients given the drug recovered more than 30 per cent faster than those on a placebo.

It is the first time any medicine has been clinically shown to improve the condition of patients with Covid-19, which has led to the deaths of more than 220,000 people across the world.

The news was enough to propel a rebound on Wall Street even after data showed the pandemic had plunged the United States into its worst economic slump in a decade, and Germany predicted its biggest recession since the aftermath of the Second World War.

It came as the World Health Organisation's emergency committee was due to meet Thursday for the first time in three months to discuss the evolution of the Covid-19 pandemic that has claimed more than 226,000 lives worldwide.

But there are mixed reports with a World Health Organisation study in China showing no impact of the drug. Senior WHO official Michael Ryan declined to weigh in on the latest findings, saying he had not reviewed the complete study.

"We are all hoping -- fervently hoping -- that one or more of the treatments currently under observation and under trial will result in altering clinical outcomes" and reducing deaths, he said.

The US National Institute of Allergy and Infectious Diseases (NIAID), which oversaw the trial, said that patients on the drug made by Gilead Sciences had a 31 per cent faster time to recovery than those on a placebo.

"Specifically, the median time to recovery was 11 days for patients treated with remdesivir compared with 15 days for those who received placebo," it said.

For Dr Anthony Fauci, who leads the NIAID and has been one of the government's point man during the crisis, "the data shows that remdesivir has a clear-cut, significant, positive effect in diminishing the time to recovery."

"Although a 31 per cent improvement doesn't seem like a knockout 100 per cent, it is a very important proof of concept because what it has proven is that a drug can block this virus," he told reporters at the White House.

The results, however, didn’t give clear evidence that people who were on the drug were less likely to die, although there was a small difference it was statistically too small to claim a benefit. The mortality rate was 8.0 per cent for the group receiving remdesivir versus 11.6 per cent for the placebo group.

The trial began on February 21 and involved 1,063 people across 68 locations in the United States, Europe and Asia.

Neither the patients nor their physicians were aware of which group they belonged to, in order to eliminate unconscious bias.

US virus fatalities soared past 60,000 on Wednesday. The country has suffered the most deaths, with Britain's toll shooting up to the world's third worst at over 26,000.

Peter Horby, an epidemiologist at the University of Oxford who was not involved in the study, said: "We need to see the full results, but if confirmed this would be a fantastic result and great news for the fight against Covid-19."

President Donald Trump, who described the news as a "positive event," said he supported an emergency use authorization for the drug, which would allow doctors to prescribe it more widely.

The chief executive of Gilead Sciences, the US laboratory that manufactures remdesivir, Daniel O'Day, said the company plans to donate the 1.5 million doses they have in stock – enough to treat at least 140,000 patients.

The company would then sell the drug at an "affordable" price, he told the health news site Stat.

Remdesivir, which previously failed in trials against Ebola, belongs to a class of drugs that act on the virus directly – as opposed to controlling the abnormal and often lethal autoimmune response it causes.

It mimics one of the four building blocks of RNA and DNA and gets absorbed into the virus's genome, short-circuiting its replication process.

In his remarks to the press, Dr Fauci indicated that the approach could pave the way for better drugs adopting the same model.

While the findings were broadly welcomed by scientists, some cautioned that the benefits were relatively modest.

"This is the first evidence that remdesivir has genuine benefits, but they are certainly not dramatic," said Stephen Evans, a medical statistics expert at the London School of Hygiene and Tropical Medicine.

"These data are promising, and given that we have no proven treatments yet for Covid, it may well lead to fast-track approval of remdesivir," said Babak Javid, principal investigator at Tsinghua University School of Medicine in Beijing.

"However, it also shows that remdesivir is not a magic bullet."

There had been mixed news about the intravenous antiviral in recent weeks.

A summary of results posted on the website of the WHO last week showed it failed in a smaller Chinese trial. The Lancet on Wednesday published the formal paper describing that experiment.

In that study of 237 patients in Wuhan, doctors found no positive effects of administering the drug compared with a control group of adults, except for those patients who required ventilators.

But the Chinese test had to be halted early because it could not recruit enough people, and was considered by many experts to be too small to be reliable.

Dr Fauci said it was "not an adequate study."

Apart from remdesivir, the antimalarial drugs hydroxychloroquine and chloroquine are also being widely used against Covid-19 on a so-called "compassionate basis" pending results from large trials.

Other therapies that are being studied include collecting antibodies from Covid-19 survivors and injecting them in patients, or harvesting antibodies from genetically engineered mice that were deliberately infected.