Remdesivir drug shows ‘clear-cut’ effect: Covid-19 patients who took the antiviral remdesivir recovered about 30 percent faster than those on a placebo, the results of a major clinical trial showed Wednesday, as the top US epidemiologist hailed the drug’s “clear-cut” benefit.

The finding represents the first time any medication has been shown to improve outcomes against the COVID-19 illness, which has claimed more than 220,000 lives globally and brought the world economy to a grinding halt.

Remdesivir cut the duration of symptoms from 15 days down to 11 in clinical trials at hospitals around the world. The full details have not been published, but experts said it would be a “fantastic result” if confirmed, but not a “magic bullet” for the disease.

Remdesivir was originally developed as an Ebola treatment. It is an antiviral and works by attacking an enzyme that a virus needs in order to replicate inside our cells.

The trial was run by the US National Institute of Allergy and Infectious Diseases (NIAID) and 1,063 people took part. Some patients were given the drug while others received a placebo (dummy) treatment.

Dr. Anthony Fauci who runs the NIAID said: “The data shows remdesivir has a clear-cut, significant, positive effect in diminishing the time to recovery.” “Although a 31 percent improvement doesn’t seem like a knockout 100 percent, 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 impact on deaths is not as clear cut. The mortality rate was 8% in people given remdesivir and 11.6% in those given a placebo, but this result was not statistically significant, meaning scientists cannot tell if the difference is real, but the results prove “a drug can block this virus” and were “opening the door to the fact that we now have the capability of treating” patients.

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.

Prof Mahesh Parmar, the director of the MRC Clinical Trials Unit at UCL, who has overseen the trial in the EU, said: “Before this drug can be made more widely available, a number of things need to happen: the data and results need to be reviewed by the regulators to assess whether the drug can be licensed and then they need assessment by the relevant health authorities in various countries.

The CEO 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.

Prof Peter Horby, from the University of Oxford, is running the world’s largest trial of Covid-19 drugs. He 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.

“However, it also shows that remdesivir is not a magic bullet in this context: the overall benefit in survival was 30%.”

Other drugs being investigated for Covid-19 include those for malaria and HIV which can attack the virus as well as compounds that can calm the immune system.

It is though the anti-virals may be more effective in the early stages, and the immune drugs later in the disease.