A World Health Organization panel advised doctors Thursday against using Gilead Sciences antiviral drug remdesivir as a treatment for patients hospitalized with the coronavrus disease, saying there is currently “no evidence” that it improves survival or shortens recovery time — standing in stark contrast to U.S. regulatory guidance on the drug.

The WHO Guideline Development Group, a panel of international experts who provide advice to the agency, said its recommendation is based on new data comparing the effects of several drug treatments, including data from four international randomized trials involving more than 7,000 patients hospitalized with the disease.

“After thoroughly reviewing this evidence, the WHO GDG expert panel, which includes experts from around the world including four patients who have had coronavirus, concluded that remdesivir has no meaningful effect on mortality or on other important outcomes for patients, such as the need for mechanical ventilation or time to clinical improvement,” the group wrote in a press release.

The recommendation was published in the British medical trade journal The BMJ on Friday in the U.K.

In an emailed statement, Gilead said remdesivir “is recognized as a standard of care for the treatment of hospitalized patients with coornavirus in guidelines from numerous credible national organizations, including the US National Institutes of Health and Infectious Diseases Society of America, Japan, UK and Germany.”

“We are disappointed the WHO guidelines appear to ignore this evidence at a time when cases are dramatically increasing around the world and doctors are relying on Veklury as the first and only approved antiviral treatment for patients with coronavirus in approximately 50 countries,” Gilead spokesman Chris Ridley said in a statement.

Remdesivir, under the brand name Veklury, is administered in a hospital setting via an IV. Gilead has said the medication should only be administered in a hospital or in a health-care setting that can provide acute care comparable with inpatient hospital care.

The majority of patients treated with remdesivir receive a five-day course using six vials of the drug. The company is also developing an inhaled version of the medication, which it will administer through a nebulizer, a delivery device that can turn liquid medicines into mist.

The drug received worldwide attention as a potentially effective treatment for the coronavirus earlier in the year after a study funded by the National Institutes of Health found that it modestly reduced the recovery time in some patients who were hospitalized with Covid-19. It was one of the drugs used to treat President Donald Trump, who tested positive for the virus last month.

On October. 22, the Food and Drug Administration formally approved the drug for adults and pediatric patients 12 years of age and older who require hospitalization for coronavirus. It is now the first and only drug approved in the U.S. to treat the coronavirus, which has infected roughly 56.4 million people worldwide and killed about1.4 million.

Gilead Sciences drug remdesivir used in 50 countries for virus rejected by WHO