Half of a study in Brazil exploring how COVID-19 patients reacted to different levels of chloroquine was stopped because of potential safety hazards, researchers said.
The double-blinded study was meant to assess the safety and effectiveness of two different chloroquine dosages in patients hospitalized with COVID-19 at Hospital e Pronto-Socorro Delphina Rinaldi Abdel Aziz in Manaus.
Patients in one group received 600 milligrams of the drug daily for 10 days while another group was getting 450 milligrams for five days, twice daily for the first day and once daily for the following days. All patients also received azithromycin, an antibiotic, along with chloroquine, which has traditionally been used against malaria, lupus, and several other illnesses.
Out of 440 patients identified, 81 hospitalized patients were enrolled. About half were given the high dosage and the others were given the lower dosage.
“High dosage of chloroquine in critically-ill patients with COVID-19 needs to be stopped now,” Marcus Lacerda, one of the researchers, who works at the Fundação de Medicina Tropical, told The Epoch Times in an email.
Researchers wrote in the study that preliminary findings suggest against high dosage of chloroquine “because of its potential safety hazards,” adding, “Such results forced us to prematurely halt patient recruitment to this arm.”
The lower-dosage arm of the study is still ongoing, Lacerda confirmed.
The article is preprint and has not been peer reviewed. It was submitted to JAMA on Monday.
Chloroquine and the closely related hydroxychloroquine have been widely touted as effective against COVID-19 across multiple countries but some recent research suggests the need for doctors to be cautious in what doses they give and which patients they choose to treat with the unproven treatments.