Several authors of a large study that raised safety concerns about malaria drugs for coronavirus patients have retracted the report, saying independent reviewers were not able to verify information that's been widely questioned by other scientists.
Thursday's retraction in the journal Lancet involved a May 22 report on hydroxychloroquine and chloroquine, drugs long used for preventing or treating malaria but whose safety and effectiveness for COVID-19 are unknown.
The study leaders also retracted an earlier report that used the same company's database on blood pressure drugs published by the New England Journal of Medicine. That study suggested that widely used blood pressure medicines were safe for coronavirus patients, a conclusion some other studies and heart doctor groups also have reached.
Even though the Lancet report was not a rigorous test, the observational study had huge impact because of its size, reportedly involving more than 96,000 patients and 671 hospitals on six continents.
Its conclusion that the drugs were tied to a higher risk of death and heart problems in people hospitalized with COVID-19 led the World Health Organization to temporarily stop use of hydroxychloroquine in a study it is leading, and for French officials to stop allowing its use in hospitals there. Earlier this week, WHO said experts who reviewed safety information decided that its study could resume.
Source : VOA