Thread by @DrMattMcCarthy

Hospitalized patients and research subjects often ask me about antibody treatments. They touch on a recurring theme: Many believe these treatments go unused because a) Doctors don't think to order them or b) We don't have the connections to acquire them. Here are key points: 1/

Monoclonal antibodies made by Regeneron and Eli Lilly are not authorized for patients who are hospitalized due to #COVID19. Trials have been stopped because antibodies don't help these patients. Nevertheless, many are distressed they're not being used. 2/
nytimes.com/2020/10/27/wor…

We've recognized the futility of giving antibodies to hospitalized patients for months, but only recently have we understood why: The timing of the antibody response is more important than the amount of antibody.
Early antibody response is crucial. 3/
medrxiv.org/content/10.110…

This is why monoclonal antibodies are targeted to high-risk outpatients. They can, in theory, get the treatment before the infection takes hold and before serious inflammation sets in. 4/
pubmed.ncbi.nlm.nih.gov/33207184/

Takeaway: To realize the potential of monoclonal antibodies, we need to greatly expand our testing capacity. Early diagnosis is crucial to catch people in the window when they can derive benefit from antibodies. By the time you're in the hospital, it's almost certainly too late.