Ivermectin doesn't prevent COVID hospital cases, large study finds

A study of COVID-19 patients at clinics in 12 Brazilian cities found that treatment with ivermectin—an antiparasitic drug—didn't prevent hospital admission compared with those in the placebo group.Early in the pandemic, before treatments were available, some looked to repurpose existing drugs such as ivermectin as possible treatments.

Some of ivermectin's proponents pushed the drug, despite inconclusive evidence and a lack of high quality studies.As the drug became a politicized hot-button issue, some patients treated themselves with animal versions of ivermectin at toxic doses.Today, the large size of the randomized, placebo-controlled trial, known as a gold standard for evaluating treatments, tilts the weight of evidence away from ivermectin benefits for COVID-19, according to the study authors.

The team published its findings yesterday in the New England Journal of Medicine.No benefit for any clinical outcomeThe study was part of a larger double-blind trial that looked at various interventions, including ivermectin, across 12 sites in Brazil's Minas Gerais state.

For the ivermectin arm of the study, researchers enrolled 3,515 lab-confirmed symptomatic COVID-19 patients, of which 679 were randomly assigned to receive ivermectin, 679 were assigned to placebo, and 2,157 were assigned to another intervention.Those in the ivermectin group received it once a day for 3 days at 400 micrograms per body weight, which the authors said in the supplementary appendix was a relatively high dose, ensuring its safety compared with most earlier trials.When the researchers weighted the two groups, 100 (14.7%) patients who received ivermectin had a primary outcome that included hospitalization or lengthy evaluation in the emergency