The World Health Organization on Wednesday said that it will resume clinical trials of anti-malarial drug hydroxychloroquine, a week after the global body decided to temporarily halt its use citing safety concerns.

The Data Safety Monitoring Board decided there was no reason to discontinue the international trial after reviewing available data on the drug, WHO Director-General Tedros Adhanom Ghebreyesus said during a press conference on Wednesday at the agency’s Geneva headquarters. “The executive group received this recommendation and endorsed the continuation of all arms of solidarity trial including hydroxychloroquine,” he said.

Use of hydroxychloroquine to prevent and treat Covid-19 has been a focus of public attention. India has been using the drug extensively and has also exported it to many foreign countries, including the United States. On May 22, the Ministry of Health and Family Welfare revised its advisory on the use of hydroxychloroquine as a prophylactic against the coronavirus. The ministry’s decision came after the National Task Force, constituted by the Indian Council of Medical Research, reviewed and recommended the use of the drug for coronavirus patients

United States President Donald Trump has also promoted the drug despite the absence of evidence to prove its effectiveness and last month said he was taking it himself in hopes of preventing the infection. In April, he lauded Indian Prime Minister Narendra Modi’s decision to supply the drug to the United States.

As of now, there’s no evidence that any drug effectively works to reduce the mortality among Covid-19 patients, WHO officials said on Wednesday.

Tedros said that the safety board will continue to closely monitor the safety of all therapeutics being tested in its trials, which include more than 3,500 patients across 35 countries. “WHO is committed to accelerating the development of effective therapeutics, vaccines and diagnostics as part of our commitment to serving the world with science, solutions and solidarity,” he said.

The decision to ban the anti-malarial drug was taken based on a study in medical journal The Lancet, published on May 22. The study had said that hydroxychloroquine could increase patient mortality rate in hospitals. The study also found that those administered the drug showed a higher frequency of arrhythmia, or irregular heartbeat. Ghebreyesus said the trial was being suspended “while the safety is reviewed”.

The chief of the Council of Scientific and Industrial Research, India’s largest chain of industrial laboratories, and two other scientists had criticised the study and said the decision to suspend trials of the drug was a “knee-jerk” reaction and opposed the move. A group of over 100 researchers also signed a letter pointing out inconsistencies in the study, and calling on the authors and The Lancet to reveal more details about their analysis