Nursing home residents who still haven't received a coronavirus vaccination can rest a little easier. Positive clinical-trial results released by Eli Lilly (LLY 0.17%) on Thursday suggest its bamlanivimab can reduce the risk of COVID-19 by 80% for nursing home residents. 

Bamlanivimab is an antibody that gloms onto the spiky part of the coronavirus responsible for COVID-19. The Food and Drug Administration has authorized it as a treatment for COVID-positive patients who are at risk of a severe infection, but not affected severely enough to require hospitalization.

Smiling scientist

Image source: Getty Images.

Results of the BLAZE-2 trial show it was highly effective at preventing COVID-19 from spreading through nursing homes that already had confirmed cases in their midst. The study enrolled 666 staff members and 299 residents who tested negative despite working or residing in facilities where the virus had already started spreading.

Overall, trial participants who received bamlanivimab were 57% less likely to show symptoms of COVID-19. Among the nursing home residents themselves, those randomized to receive bamlanivimab were 80% less likely to contract COVID-19 compared to residents in the same facility who received a placebo. There were four deaths attributed to COVID-19 among the group of 299 nursing home residents in the BLAZE-2 trial, and all four occurred among volunteers randomized to receive a placebo.

Since it received Emergency Use Authorization to treat patients who have already tested positive for COVID-19, hospitals haven't been eager to administer large intravenous infusions of bamlanivimab to COVID-positive patients who are healthy enough to send home. Today's clinical trial results could give Eli Lilly's treatment another chance to make an impact.