New Covid-19 variants are eluding antibody treatments and may render vaccines less effective. To keep up, physicians need a broader arsenal of therapies that the virus can't easily defeat. But the Food and Drug Administration has authorized precious few treatments for Covid-19, namely Gilead's antiviral remdesivir and monoclonal antibodies by Regeneron Pharmaceuticals and Eli Lilly. The National Institutes of Health has prioritized monoclonal antibodies—essentially manufactured copies of human antibodies—which have shown promise against other diseases, including cancer.
