The experimental coronavirus vaccine of Gilead Sciences Inc. failed its first randomized clinical trial, announced on April 23, 2020, but the drugmaker said the findings of the test in China were inconclusive as it was completed early. Gilead's stock dropped almost 6% to $76.56, which comes days after a new study documenting the rapid recovery of fever and respiratory symptoms in COVID-19 patients at the University of Chicago Medicine Hospital.

The Chinese trial revealed that antiviral remdesivir has not improved the condition of patients or decreased the presence of the pathogen in the bloodstream, the study said, citing draft documents accidentally released by the World Health Organization (WHO).

Gilead said in a statement that the post contained improper characteristics of the study and that the research was terminated early due to low enrollment and was therefore underpowered to make statistically significant conclusions.

" The results of the study are inconclusive, while patterns in the data indicate a potential benefit for remdesivir, particularly among patients treated early in illness, "the company said. WHO said a draft document given by the authors of the study was inadvertently posted on the website. It was taken down as soon as the mistake was found, the agency said adding the manuscript is undergoing peer re-evaluation.

Gilead is testing the drug in several trials and widely awaited clinical results are due later this month from a study involving 400 patients infected with serious cases of the disease. Scientists in China have examined 237 patients, giving the treatment to 158 patients, and contrasting their success with the other 79. The drug also had major side effects in others, which indicated that it had been taken off by 18 patients.

The interest in Gilead's drug was strong, as there are currently no approved drugs or preventive vaccines for COVID-19, and doctors are desperate for something that could alter the course of the disease that affects the lungs and in extremely serious cases can shut down other organs.

However, in the week of 23 April 2020, a trial in China which tested the drug in those with mild COVID-19 symptoms was suspended due to a lack of qualified patients, marking the second trial of remdesivir in the country to be terminated.

The drug, which previously failed as an Ebola cure, is being tested against COVID-19 as it is intended to disable the mechanism by which certain viruses, like the current coronavirus, make copies of themselves and potentially overpower the immune system of their host.