It is the first potential treatment for patients with mild or moderate Covid-19. (The two other treatments that have proved helpful, the antiviral remdesivir and the steroid dexamethasone, are only for the seriously ill.)
Scientists used blood plasma from Covid-19 survivors, isolating and testing their antibodies to find the most powerful ones. They then manufactured vats of antibodies to make the drug. In a trial of more than 450 newly diagnosed Covid-19 patients, Eli Lilly said, only about 1.7 percent of those who received the drug ended up in the hospital, compared with 6 percent who were given a placebo — a 72 percent risk reduction. Those treated with the drug reportedly also had fewer symptoms, and the levels of virus in their bodies plummeted.
Other companies are also working on treatments with monoclonal antibodies, but they are difficult and expensive to make. A single dose could cost thousands of dollars. They offer only a temporary solution, with the antibodies lasting about a month.
But without a vaccine — the only way to elicit a lasting immune response — the treatment could give doctors another weapon in an arsenal with few options.
The study will eventually enroll 800 patients in the U.S. of all ages and risk categories, including people in nursing homes. Eli Lilly has already started manufacturing 10,000 doses in hopes that these interim results, which have not yet been peer reviewed, will bear out.
The company plans to discuss the state of the trial with the Food and Drug Administration, as well as the possibility of emergency use authorization to market the drug.