Results from Eli Lilly were published Wednesday in the New England Journal of Medicine. The company’s interim analysis showed its monoclonal antibody treatment seemed to lower the risk of hospitalization and ease some symptoms in a small number of patients with a mild to moderate case of Covid-19.

The Phase 2 trial involved 452 patients, some of whom received the treatment and some of whom received a placebo, which does nothing. Only 1.6% of patients who took the treatment had symptoms progress enough that they had to be hospitalized or seek care at the emergency room. For patients who got the placebo, it was 6.3%.

For patients in higher risk categories — those who were 65 years or older or obese — 4% who got the treatment were hospitalized. For those who got the placebo, it was 15%. Those who received the treatment also had slightly less severe symptoms than those who got the placebo.