Pharmaceutical giant Eli Lilly and Company announced Wednesday that its antibody treatment reduced the incidence of hospitalizations in patients with mild to moderate symptoms of COVID-19 in clinical trials.

The drug, called LY-CoV555, was developed to help block the coronavirus from entering human cells. That resulted in a 72% reduction in the risk of patients requiring hospitalization, said the company.

According to the South China Morning Post, our bodies make antibodies to ward off foreign substances such as viruses. An antibody treatment is not a vaccine and does not provide permanent protection against SARS-CoV-2, the virus that causes COVID-19. Instead, a person who receives antibody protection gets passive immunization, according The History of Vaccines. The protection offered by the antibodies is short-lived but works right away.

The Eli Lilly drug works by neutralizing the spike protein on the SARS-CoV-2 virus. It was manufactured by using the blood from one of the first recovered patients in the U.S. No adverse side effects were reported in the clinical trial.

“These interim data suggest that LY-CoV555 has a direct antiviral effect and may reduce COVID-related hospitalizations,” said Dr. Daniel Skovronsky, M.D., the chief medical officer for Eli Lilly, according to the Post. “The results reinforce our conviction that neutralizing antibodies can help in the fight against COVID-19.”

The Post says that another company, Regeneron Pharmaceuticals, is also expected to reveal data on its late stage clinical trial of its antibody drug, REGN-COV2. According to CNN, it’s the first potential treatment that uses two antibodies instead of one to fight the virus.

LY-CoV555 is currently being tested in nursing homes across the country to see if it can reduce the spread of COVID-19 infections among staff and residents, according to the Post.