The first results on experimental antiviral drug Remdesivir were encouraging, but it is still too early to draw definitive conclusions from the data, according to a recent study published in the New England Journal of Medicine.
Remdesivir, made by American pharmaceutical company Gilead Sciences, is not yet licensed or approved anywhere globally while multiple Phase 3 studies are ongoing to determine the safety and efficacy of the drug for the treatment of COVID-19.
According to the study published Friday, a total of 53 patients hospitalized with severe complications of COVID-19 were treated with the antiviral drug on an individual compassionate use basis, but not a double-blind, placebo-controlled trial.
Of all these patients, 25, nearly half in the cohort, were discharged from the hospital, the study said.
Among 30 patients on mechanical ventilation at baseline, 17 were extubated, while the result of four other patients on extracorporeal membrane oxygenation was unclear, it said.
After 28 days of follow-up, the cumulative incidence of clinical improvement, defined as discharge from the hospital and/or at least a two-point improvement from baseline on a predefined six-point scale, is 84 percent, it said.
"The majority of patients in this international cohort demonstrated clinical improvement and no new safety signals were identified with Remdesivir treatment," Gilead said in a statement.
The overall mortality rate was 13 percent, with six patients on invasive ventilation and one patient on noninvasive oxygen support, the study said.
Clinical improvement is less frequent among patients on invasive ventilation than non-invasive ventilation, it said, adding factors associated with an increased risk of mortality included age greater than 70 years and reduced kidney function.
"Currently there is no proven treatment for COVID-19. We cannot draw definitive conclusions from these data," said Jonathan D. Grein, director of Hospital Epidemiology of Cedars-Sinai Medical Center in Los Angeles and lead author of the study.
"We look forward to the results of controlled clinical trials to potentially validate these findings," he said.
"Compassionate use data have limitations due to the small size of the cohort, the relatively short duration of follow-up, potential missing data due to the nature of the program and lack of a randomized control group," said Gilead.
"While the outcomes observed in this compassionate use analysis are encouraging, the data are limited," said Merdad Parsey, the company's chief medical officer, confirming there are multiple clinical trials underway for Remdesivir with initial data expected in the coming weeks.