Prominent Study Showing Severe Hydroxychloroquine Risk Is Retracted

Hydroxychloroquine has been used to treat COVID-19 patients. A new study suggests that’s a bad idea. Photo: Soumyabrata Roy/NurPhoto via Getty Images

UPDATE: After a sustained period of criticism, The Lancet took the unusual step of retracting a published study showing that the drugs hydroxychloroquine and chloroquine increased mortality among patients with coronavirus.

Three of the study’s authors had requested the retraction after outside observers raised questions about the study’s data. In an open letter sent to The Lancet last week, more than 100 doctors pointed to many possible flaws in the study’s methodology and inquired about the transparency of Sugisphere, the company that had collected the study’s data — supposedly from 96,000 coronavirus patients. The company refused to submit to an independent review of their collection methods, and in their letter on Thursday, the three researchers said that they “can no longer vouch for the veracity of the primary data sources.”

Another study relying on the same data, this one in the New England Journal of Medicine, was retracted shortly after The Lancet took action.

But a separate study published in that journal on Wednesday — the first to adhere to gold standards in clinical trials — found that taking the drug prophylactically, as President Trump has done, does not protect people contracting the coronavirus.

Intelligencer’s previously published article is below.

A new observational study conducted on the effect of hydroxychloroquine and chloroquine on COVID-19 patients found that the medications provide no benefit and are actually “associated with an increased risk of in-hospital mortality.” The study, which is the largest of its kind conducted on the drugs, was published in The Lancet Friday.

For the study, researchers reviewed the cases of just over 96,000 patients treated for COVID-19 in 671 hospitals across six continents. Close to 15,000 of them were treated with hydroxychloroquine or chloroquine, which have both been used to treat malaria and autoimmune disorders for years. Some patients received one of the drugs by itself. Some took an antibiotic, too.

The patients who received the drugs suffered worse fates that those who didn’t, CNN reports:

About 1 in 11 patients in the control group died in the hospital. About 1 in 6 patients treated with chloroquine or hydroxychloroquine alone died in the hospital. About 1 in 5 treated with chloroquine and an antibiotic died and almost 1 in 4 treated with hydroxychloroquine and an antibiotic died.

The treatments were also associated with a higher rate of dangerous heart arrhythmia.

The researchers write that because their study was observational, they cannot “exclude the possibility of unmeasured confounding factors.” Therefore, they write, “Randomised clinical trials will be required before any conclusion can be reached regarding benefit or harm of these agents in COVID-19 patients.”

Still, the researchers have seen enough to feel confident that the drugs are not an effective treatment for COVID-19. “Justification for repurposing these medicines in this way is based on a small number of anecdotal experiences that suggest they may have beneficial effects for people infected with the SARS-CoV-2 virus,” Frank Ruschitzka, a co-author of the study, said in a statement. “However, we now know from our study that the chance that these medications improve outcomes in COVID-19 is quite low.”

The physician Eric Topol, speaking to the Washington Post, provided an even more stark assessment: “It’s one thing not to have benefit, but this shows distinct harm. If there was ever was hope for this drug, this is the death of it.”

Prominent Study Showing Hydroxychloroquine Risk Is Retracted