The first U.S. human trial of an antibody to combat COVID-19 is currently underway in several sites across the country. The treatment called REGN-COV2 was developed by Regeneron Pharmaceuticals in New Jersey, and the company said that if the trials are successful, the drug will be available by the fall.

It's the first potential treatment that uses two antibodies instead of one to fight the virus, CNN reports. An antibody is a protein that the body manufactures to ward off threats from pathogens. It's not a vaccine and does not provide permanent protection against viruses like SARS-CoV-2, the virus that causes COVID-19. Instead, a person who receives antibody protection gets passive immunization, according to The History of Vaccines. The protection offered by antibodies is short-lived, but it works right away.

Regeneron scientists have been working for years preparing for a pandemic like COVID-19, according to CNN, and even ran speed challenges to see how fast they could develop treatments for emerging threats.

"Most scientists have said for years there's potential for pandemics like this novel coronavirus to emerge," Regeneron scientist Kristin Pascal told CNN. "So we thought, let's be prepared."

The trials will involve four separate populations: those hospitalized with COVID-19; those who are ill and not hospitalized; healthy people at high-risk; and healthy people who have not come into contact with anyone who has been sick. The first trial will determine the safety of the drug.

"Our work inventing novel antibodies has shown that individual antibodies, no matter how good, are likely not enough against the devastating virus that causes COVID-19," said George D. Yancopoulos, M.D., president and chief scientific officer at Regeneron, according to a press release. "The concept that drug cocktails can prevent viral escape has been previously demonstrated for traditional antiviral drugs used to treat HIV and other viruses."

The company said it set a speed record in developing REGN-COV2 in a matter of months, CNN reported.