Gilead Sciences Inc. shares gained Monday after a senior World Health Organization official said the company’s experimental drug may be the best bet to find a treatment for the new coronavirus that’s spreading around the globe.

Gilead’s compound, remdesivir, has been rushed into a clinical trial in China, where the illness has infected tens of thousands of people. WHO officials have said results could be available within weeks.

Remdesivir is the “one drug right now that we think may have efficacy,” Bruce Aylward, an assistant director-general at the World Health Organization, said at a briefing in Beijing. WHO officials and international scientists are in the country assessing the outbreak.

Gilead shares (GILD) advanced as much as 6.9% in New York on Monday. A Gilead spokesperson didn’t immediately respond to a request for comment before business hours in Foster City, California, where the company is based.

Outbreaks of new or rare infectious diseases can prompt a rush of efforts to find effective therapies, with trials often conducted in sometimes-chaotic field conditions. But not all work -- many of the drugs tested against Ebola during outbreaks over the past decade failed, despite initial hopes they could save some patients from that deadly virus.