A study coordinated by the World Health Organization has indicated that remdesivir, along with three other potential drug treatments for the coronavirus, has "little or no effect" on death rates among hospitalized patients.
The interim results from the WHO's Solidarity Therapeutics Trial, said to be the world's largest randomized control trial of coronavirus treatments, were published Thursday.
The results indicated that the remdesivir, hydroxychloroquine, lopinavir/ritonavir and interferon drug treatment regimens "appeared to have little or no effect on 28-day mortality or the in-hospital course of COVID-19 among hospitalized patients."
Remdesivir is one of the drugs given to U.S. President Donald Trump after he tested positive for the coronavirus two weeks ago.
The randomized study by the WHO was conducted in 405 hospitals across 30 countries on 11,266 patients, with 2750 given remdesivir.
"No study drug definitely reduced mortality (in unventilated patients or any other subgroup of entry characteristics), initiation of ventilation or hospitalisation duration," the authors of the study wrote.
Randomized controlled trials are considered the "gold standard" of clinical studies because they more effectively eliminate bias. However, the WHO study has not yet been peer reviewed, which means it has not been independently evaluated by other experts.
The WHO's findings come a week after drugmaker Gilead Sciences published the final data on its own large-scale trial of remdesivir. Gilead originally developed remdesivir to treat the Ebola virus.
The Gilead study, of 1,060 patients hospitalized with Covid-19, found that remdesivir contributed to significantly-reduced mortality among those in the early stages of receiving oxygen support. However, it did not find a statistically significant reduction in death rates across the entirety of patients treated in the trial.
Gilead Sciences CEO Daniel O'Day told CNBC that the drug was also found to prevent people "getting sicker," and "from going onto more oxygen support." The study also used the randomized controlled method and was peer reviewed.
Gilead Sciences was not immediately available for comment on the WHO's study when contacted by CNBC.
Last week, it was reported that Europe was stocking up on supplies of redesivir amid a resurgence of coronavirus cases in the region. Gilead Sciences said it had agreed to sell up to 500,000 courses of the drug to 37 European countries.
However, despite a growing interest in treatments for the coronavirus, the timeline for a possible vaccine is still up in the air. Ngozi Okonjo-Iweala, board chair of the Vaccine Alliance, known as GAVI, said on Thursday that there was still hope for a vaccine to be ready between the first quarter and middle of next year.
"Of course, vaccines are not a magic bullet and we can't guarantee, but the work that is going on so far looks very promising," she said during a CNBC panel on the global economy on Thursday.