Pfizer Inc. said yesterday that it will shell out $55 million to bring to an end to litigation surrounding Protonix, an acid reflux drug that Wyeth, now owned by Pfizer, produced and marketed in the early 2000s.

The Department of Justice (DOJ) had accused Wyeth of marketing Protonix for unapproved uses and says the pharmaceutical company also made claims about the drug that had not been proved. The DOJ says the questionable marketing of Protonix occurred between February 2000 and June 2001. Pfizer purchased Wyeth for $68 billion in 2009.

The DOJ says Wyeth trained its sales team to promote Protonix to treat all forms of gastro-esophageal reflux disease (GERD), but the Food and Drug Administration had only approved the drug for GERD that is diagnosed via endoscopy. Promoting it for all forms of GERD, the DOJ contends, opened Protonix up to a vastly wider market.