The Lancet's Hydroxychloroquine Study Is Retracted by Its Authors

The observational dataset on which it was based could not be properly audited.


The Lancet published a high profile study on May 22 purporting to show that treating hospitalized COVID-19 patients actually increased their risk of death. Three authors of the study are now retracting it.

The study was based an observational database assembled by medical data aggregation firm Surgisphere which claimed to have access to the medical records of nearly 100,000 COVID-19 patients treated in hundreds of hospitals across the globe. Outside researchers almost immediately began questioning the accuracy and plausibility of the Surgisphere data.

In response Surgisphere promised to pursue an immediate independent audit of its dataset. Yesterday, the editors of The Lancet issued an Expression of Concern about the article and noted that they were awaiting the results of the promised audit.

The retraction statement issued this afternoon by three of the article's authors declares:

We launched an independent third-party peer review of Surgisphere with the consent of Sapan Desai to evaluate the origination of the database elements, to confirm the completeness of the database, and to replicate the analyses presented in the paper.

Our independent peer reviewers informed us that Surgisphere would not transfer the full dataset, client contracts, and the full ISO audit report to their servers for analysis as such transfer would violate client agreements and confidentiality requirements. As such, our reviewers were not able to conduct an independent and private peer review and therefore notified us of their withdrawal from the peer-review process.

We always aspire to perform our research in accordance with the highest ethical and professional guidelines. We can never forget the responsibility we have as researchers to scrupulously ensure that we rely on data sources that adhere to our high standards. Based on this development, we can no longer vouch for the veracity of the primary data sources. Due to this unfortunate development, the authors request that the paper be retracted.

The Lancet noted that the article will be updated shortly to reflect the retraction.

This notable retraction will surely act as an accelerant to the ongoing politicized firestorm over the efficacy of the antimalarials hydroxychloroquine and chloroquine as treatments for COVID-19.

In other news, the New England Journal of Medicine has just published a randomized placebo-controlled study that found that hydroxychloroquine is not an effective preventive treatment for people exposed to the coronavirus that causes COVID-19. In that study, half of a cohort of 800 participants who had been exposed to COVID-19 were randomly given doses of hydroxychloroquine and half were supplied with a placebo. "After high-risk or moderate-risk exposure to Covid-19, hydroxychloroquine did not prevent illness compatible with Covid-19 or confirmed infection when used as postexposure prophylaxis within 4 days after exposure," concluded the researchers.

The results of further randomized controlled studies of the two antimalarials in combination with other drugs in the next couple of months should provide more definitive answers as to their efficacy with respect to treating COVID-19.