A packet of Nivaquine tablets containing chloroquine, a commonly used malaria drug. Gerard Julien/AFP/Getty Images

World Health Organization officials said that chloroquine, a drug typically used to treat malaria, will be one option included in a large, global clinical trial evaluating potential coronavirus treatment.

“There’s some indications that it could be useful but there are no clear-cut studies that have been rigorously done to either prove or disprove that chloroquine is effective,” WHO chief scientist Dr. Soumya Swaminathan said during a call with reporters on Monday.

This comes after the announcement President Trump made last week that the US Food and Drug Administration approved the “very powerful” drug chloroquine to treat coronavirus and that there were “very, very encouraging early results.”

The FDA later tempered the President's remarks regarding chloroquine as an approved treatment, noting larger studies are needed to draw conclusions.

Currently there are no treatments — including chloroquine —that have proven safe and effective against Covid-19, WHO Director-General Tedros Adhanom Ghebreyesus said in a separate press briefing on Monday.

“There is a desperate need for effective therapeutics. There is currently no treatment that has been proven to be effective against Covid-19,” Tedros said on Monday.

WHO announced last week that it had organized the SOLIDARITY trial to examine potential treatment options for Covid-19 — chloroquine being one of them.

“We understand that this situation is very complex. Everybody, including President Trump, is trying to identify treatments that could help their people. And I think everybody is interested in further exploring the potential of chloroquine, so we are,” said Dr. Ana Maria Henao-Restrepo, a medical officer at WHO's Department of Immunization Vaccines and Biologicals.

Even without clinical evidence, some patients with Covid-19 are already taking chloroquine, but there could be harm in that too, Swaminathan said. Over the weekend, three people in Nigeria overdosed on the drug, which can cause seizures, nausea, vomiting, deafness, vision changes and low blood pressure.

“We have no knowledge that it’s going to benefit anyone,” Swaminathan said. “It is a really important point to focus our efforts on generating the evidence which could then be used to treat people properly and effectively.”