New hope for anti-viral drug remdesivir to treat coronavirus infection

The largest and most rigorous trial of anti-viral drug remdesivir has provided the first glimmer of hope in finding an effective drug to treat the coronavirus infection, which has infected more than three million people worldwide. The trial was set up to test the effectiveness of Remdesivir in treating COVID-19, the disease caused by the novel coronavirus (SARS‑CoV‑2).

The drug works by blocking an enzyme that some viruses use to copy their RNA, which prevents the virus from replicating. However, conflicting studies have cast doubt upon the potential usefulness of the drug, with earlier trials showing conflicting results and some showing no effect against COVID-19.

The US-based trial, which began on 21 February and is sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), has been the most rigorously designed test of the drug so far, comparing remdesivir to placebo in 1063 patients at 68 sites in the US.

The preliminary findings announced on 29 April have increased hopes that the drug can shorten the recovery time from a coronavirus infection. The experimental drug, made by Gilead Sciences of Foster City, California, might soon become the standard of care in the US, according to Anthony Fauci, director of the NIAID.

Fauci said that those taking remdesivir recovered in 11 days on average versus 15 days for the placebo group. Fewer deaths were also reported among those who received the drug, but the difference was not significant (8 per cent versus 11.6 per cent in the group given the placebo).

Despite relatively modest benefits, the trial has proven that a drug can block this virus. Fauci explained: “Although a 31% improvement doesn’t seem like a knockout, 100% [success], it is a very important proof of concept”. Based on the positive data, remdesivir must now be offered to all study participants, and trials of other treatments now underway must start to offer the drug instead of a placebo, said Fauci.

The results of two smaller trials were also announced on the same day. One trial performed by the drugmaker showed that half of the 400 participants recovered within 2 weeks of receiving treatment, however, the trial lacked a placebo group. Another small trial in China showed no significant improvement after treatment. However, the trial was halted early owing to the decline in COVID-19 cases in the country.

Even before the announcement of the NIAID trial results, Gilead has been ramping up production of the remdesivir and is hoping to produce enough remdesivir to treat more than a million patients by the end of the year.

Remdesivir may not be a silver bullet. Indeed, the positive findings do not mean an end to the race to find a drug that works against the coronavirus. Much like early treatments of HIV in the 1980s, clinicians will likely rely on a cocktail of antiviral drugs to treat the coronavirus infection, which could eventually lead to highly effective therapies.

With no vaccine on the horizon as yet, effective therapies could, at the very least, reduce the number of deaths due to the coronavirus and limit the economic damage from the pandemic.