Thoughts on the Prevent Senior study

A new study from Brazil is reporting significant positive effects of hydroxychloroquine (HCQ) + azithromycin (AZM) on early-stage suspected COVID19 cases. The study was posted as a preliminary manuscript draft on Dropbox a couple of days ago. I just tweeted my thoughts in a long thread, but here is a bit more polished version.

Update 20 April: It was announced today that the study described below has been suspended because of ethical violations. As pointed out by Natalia Pasternak and Carlos Orsi and Ricardo Parolin Schnekenberg (see Additional Reading links below), the study had already started before the ethical approval had been obtained. This could be figured out by looking at the disclosed study days in the preprint and the trial registration at the Clinical Trials website.

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An observational study without a control group

This blog post is based on a Twitter thread I did on March 27, 2020, after seeing Mathieu Rebeaud’s Tweet about a new white paper from the institute of Didier Raoult. That not-yet peer reviewed paper describes a group of 80 COVID-19 patients, all treated with a combination of hydroxychloroquine and azithromycin. This treatment had shown some promising results in a very small, not well-executed study by the same group. Unfortunately, this second study does not have a control group and the patients did not appear to be very sick. So here is my critical review.

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