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Rapid response to:

Feature Covid-19

Covid-19: The inside story of the RECOVERY trial

BMJ 2020; 370 doi: (Published 08 July 2020) Cite this as: BMJ 2020;370:m2670

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Rapid Response:

Dose Related Toxicity of Hydroxychloroquine

Dear Editor
The story behind the dosage of Hydroxychloroquine used in the RECOVERY trial gets curiouser and curiouser. David Jayne drew attention to the potentially lethal dose of the drug used in the trial.

Martin Landray, has defended the dosage used. He told the BMJ, that the dose was arrived at using “detailed pharmacokinetic models” developed by Nick White and his team “to rapidly achieve drug levels that might be high enough to kill the virus but not so high as to trigger toxicity”. Landray went on to say the work is now published in a preprint on medRxiv.

The preprint article does not appear to be the basis on which the dosage used in the trial was decided. It merely states, in retrospect, that “the majority of chloroquine regimens trialled in COVID-19 should not cause serious cardiovascular toxicity”.

The real reason patients were given such high doses of Hydroxychloroquine remains the proverbial riddle, wrapped in a mystery, inside an enigma. The authors of the BMJ’s feature article note the criticisms from scientists about lack of transparency in the trial. If this is not addressed, it will erode trust in such trials.

Competing interests: No competing interests

12 July 2020
Jacob Puliyel
Holy Family Hospital, Delhi
Holy Family Hospital, Delhi