The sprint to find medical breakthroughs to contain Covid-19 stumbled this week, as a pair of pharmaceutical giants working to develop treatments and vaccines suffered setbacks in the clinic.
On Tuesday, Eli Lilly & Co. said that enrollment in a government-sponsored clinical trial of its antibody therapy had been paused out of safety concerns. That came less than 24 hours after Johnson & Johnson said research on its experimental vaccine was paused after a study volunteer fell ill.
The developments are likely to heighten worry that the pursuit of products to prevent and treat infections is moving too quickly. Regulators and drugmakers