Gilead Sciences' experimental coronavirus drug failed its first randomized clinical trial, the Financial Times has reported, but the drugmaker said the results from the study in China was inconclusive as it was terminated early.

Shares of Gilead fell nearly 6% to $76.56 after the FT story, which comes days after a recent report detailed rapid recovery in fever and respiratory symptoms in COVID-19 patients at the University of Chicago Medicine hospital.

The Chinese trial showed the antiviral remdesivir did not improve patients' condition or reduce the pathogen's presence in the bloodstream, the report said, citing draft documents published accidentally by the World Health Organization (WHO).

Gilead said in a statement the post included inappropriate characterizations of the study and that the study was terminated early due to low enrollment and, as a result, it was underpowered to enable statistically meaningful conclusions.

"The study results are inconclusive, though trends in the data suggest a potential benefit for remdesivir, particularly among patients treated early in disease," the company said.

The WHO said a draft document provided by the authors of the study was inadvertently posted on the website. It was taken down as soon as the mistake was noticed, the agency said adding the manuscript is undergoing peer review and a final version is awaited.

Gilead is testing the drug in multiple trials and highly anticipated trial results from a study involving 400 patients hospitalized with severe cases of the illness are expected later this month.

Researchers in China studied 237 patients, giving the drug to 158 and comparing their progress with the remaining 79.

The drug also showed significant side effects in some, which meant 18 patients were taken off it, according to the Financial Times.

Interest in Gilead's drug had been high as there are currently no approved treatments or preventive vaccines for COVID-19, and doctors are desperate for anything that might alter the course of the disease that attacks the lungs and can shut down other organs in extremely severe cases.

Last week, however, a trial in China testing the drug in those with mild symptoms of COVID-19 was suspended due to a lack of eligible patients, marking the second remdesivir trial in the country to be terminated.

The drug, which previously failed as a treatment for Ebola, is being tried against COVID-19 as it is designed to disable the mechanism by which certain viruses, including the new coronavirus, make copies of themselves and potentially overwhelm their host's immune system.