(Nature) – Paper on hydroxychloroquine led by French researcher Didier Raoult is second-most-cited study ever to be withdrawn.

A study that stoked enthusiasm for the now-disproven idea that a cheap malaria drug can treat COVID-19 has been retracted — more than four-and-a-half years after it was published.

Researchers had critiqued the controversial paper many times, raising concerns about its data quality and an unclear ethics-approval process. Its eventual withdrawal, on the grounds of concerns over ethical approval and doubts about the conduct of the research, marks the 28th retraction for co-author Didier Raoult, a French microbiologist, formerly at Marseille’s Hospital-University Institute Mediterranean Infection (IHU), who shot to global prominence in the pandemic. French investigations found that he and the IHU had violated ethics-approval protocols in numerous studies, and Raoult has now retired. (Read More)