Chloroquine Study Involving High Dosage Partially Halted Over Risk of Complications

Hydroxychloroquine and chloroquine tablets are shown in at the IHU Mediterranee Infection Institute in Marseille, France, on Feb. 26, 2020. Gerard Julien/AFP via Getty Images

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.