Drug companies may face products liability claims in Pennsylvania for defectively designed drugs, the state Supreme Court has ruled on a 4-2 vote in a case stemming from the fatal use of a diet drug made by a Pfizer subsidiary that was later taken off the market.

The majority rejected the argument that manufacturing defects and inadequate warnings are the only viable products liability claims against pharmaceutical companies, and allowed claims to go forward alleging the drug company negligently designed and marketed the diet pill. The court issued its 47-page majority opinion in Lance v. Wyeth on Wednesday.