Philadelphia’s mass tort litigation over recalled heartburn medication Zantac has surged to encompass over 600 cases as plaintiffs lawyers across the U.S. opt to file suits in state court rather than in the federal multidistrict litigation.

The Zantac program is now the largest of four mass torts to have been established in Philadelphia’s Complex Litigation Center in 2022. The litigation’s 640-case docket dwarfs the other three programs, which each have case lists hovering between 120 and 150, according to the court’s website.