Drug companies including Sanofi S.A. and Pfizer Inc. have brought in some of the nation’s top defense attorneys in more than two dozen lawsuits brought over last month’s recall of over-the-counter heartburn medication Zantac.

Anand Agneshwar, co-chairman of Arnold & Porter Kaye Scholer’s products liability litigation practice, made an appearance Wednesday before the U.S. Judicial Panel on Multidistrict Litigation on behalf of Sanofi, which voluntarily recalled Zantac on Oct. 18 after the U.S. Food and Drug Administration discovered it contained an ingredient linked to cancer. Mark Cheffo, co-chairman of the products liability and mass torts practice at Dechert, appeared for GlaxoSmithKline, which first received FDA approval to sell Zantac in 1983. GlaxoSmithKline has a U.S. unit based in Philadelphia.