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Covid-19: 146 researchers raise concerns over chloroquine study that halted WHO trial

BMJ 2020; 369 doi: (Published 02 June 2020) Cite this as: BMJ 2020;369:m2197

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  1. Elisabeth Mahase
  1. The BMJ

A group of international researchers has raised methodological and data integrity concerns about a recent study on hydroxychloroquine and chloroquine in covid-19 patients, which led to the World Health Organization halting part of its trial.

The observational study, published in the Lancet,1 reported that inpatients with covid-19 who were treated with chloroquine or hydroxychloroquine (with or without a macrolide) showed an increased risk of dying in hospital and of de novo ventricular arrhythmia than patients who did not receive the drugs.2

WHO has been testing potential covid-19 treatments through its Solidarity Trial, involving over 400 hospitals in 35 countries. After the publication of the Lancet paper, which included patients from six continents, WHO announced that the hydroxychloroquine arm of the trial had been halted while the Data Safety Monitoring Board reviewed the data.

In an open letter to the study’s authors and the journal’s editor, Richard Horton, however,3 146 clinicians, medical researchers, statisticians, and ethicists have now highlighted 10 main concerns about the research.

Further error checking

The concerns outlined in the open …

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