Remdesivir shows promise against COVID-19, but more trials needed: Scientists

Researchers claim that COVID-19 patients in a clinical trial are responding quickly to Remdesivir, a finding which they said is "promising," while also emphasising the need for more trials to test the effectiveness of the antiviral drug.

According to the researchers from the Houston Methodist Hospital in Texas, US, the trial's criteria allows for the treatment of patients early in their clinical course, and in some cases when they may have otherwise been intubated.

"Early results are promising, and that is important right now. Much of what we are learning about COVID-19 management is centred around preventing quick deterioration," said Katherine K. Perez, an infectious diseases pharmacist from Houston Methodist Hospital in the US.

"Timing is everything. I can't say for certain they would have been intubated otherwise, but it's encouraging," Perez said.

Originally developed to treat Ebola more than a decade ago, Remdesivir is a broad-spectrum antiviral drug, according to a study, published in the journal Nature earlier this year.

The Chinese study showed that Remdesivir could successfully block the novel coronavirus, SARS-CoV-2, from replicating in human cells.

Another research, published in the New England Journal of Medicine, chronicled the case of a COVID-19 positive man, who received Remdesivir at the recommendation of the US Centers for Disease Control and Prevention, and reportedly started improving within 24 hours.

"One of the most challenging things with COVID-19 is the way this virus makes copies of itself once it finds its way into the body," the hospital said in a statement to the press.

"This is how COVID-19 can ultimately take over and send someone into respiratory distress and in need of intubation if not stopped early enough. Remdesivir has demonstrated a potent ability to inhibit this viral replication in human cells and is now being tried in clinical trials of patients with the SARS-CoV-2 virus," it noted.

The hospital was the fifth site in the US to join the clinical trials for the drug, and has been enrolling and treating patients since mid-March, the press statement said.

Initially, five patients received early access to Remdesivir on a compassionate use basis, and since being activated as a clinical trial site, the hospital said more than 35 patients have been enrolled.

The two human-stage clinical trials at Houston Methodist are randomised, multicenter studies where both the patients and the clinicians know which treatment is being prescribed.

In both the trials, the clinicians said they are treating patients with moderate to severe symptoms to evaluate the safety and efficacy of Remdesivir in adults diagnosed with COVID-19.

One study is for patients with moderate COVID-19 and tests either a 5-day or 10-day Remdesivir treatment, and the other is evaluating a 10-day course of Remdesivir for patients with severe COVID-19, including those on mechanical ventilation, the hospital noted.

Perez said the early results have been promising, with courses being well tolerated by patients.

"If given early enough, we're hoping that Remdesivir interferes with the virus and blocks its ability to replicate in patients' cells. The goal is that it staves off the deadly inflammatory cascade that leads to respiratory failure and the need to be intubated and put on a ventilator," said infectious diseases physician Kevin A. Grimes from Houston Methodist.

Perez added that a number of them who have undergone treatment with Remdesivir are showing signs of recovery and have been released from the hospital to go home.

However, she cautioned that it is too soon to tell whether the drug is an effective cure.

According to the clinicians, additional data from several ongoing randomised, controlled clinical trials, including the ones at Houston Methodist, will provide more definitive, evidence-based conclusions regarding the safety and efficacy of Remdesivir for treating COVID-19.