Phase IIb open randomized clinical trial to evaluate the efficacy and safety of chloroquine chemoprophylaxis in healthcare professionals at high risk for SARS-CoV-2 infection

This study in Brazil is evaluating the efficacy of a weekly dose of chloroquine to prevent COVID-19 in health workers who provide direct care to confirmed or suspected COVID-19 patients, and its efficacy in reducing the severity in health care workers who do become infected.

Primary objective: To assess if Chloroquine results in a more rapid decline in viral load in throat/nose swabs in patients with COVID-19

Type of study: Phase IIb trial, therapeutics

Treatment tested: Chloroquine

Countries: Brazil

Number of sites: 4

Sample size: 1,000

Study participants: Hospitalized adults with laboratory confirmed SARS-CoV-2 infection

Study status: Recruiting

Principal investigators

More information


Last updated: July 2020


Note that study-related documents posted on the COVID-19 Clinical Research Coalition (COVID-19 CRC) website have been shared by coalition members for information. Some may have been approved by Ethics Review Boards and others may still be in draft form. Documents posted here may have been further amended before being used in the conduct of the respective trials they were designed for. It is recommended that users review these documents carefully and, if they plan to use them, adapt them appropriately for their intended use. The COVID-19 CRC and its members cannot accept any liability for any claim, loss or damages as a result of any reliance placed on, or use of, these documents.

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