(CN) - The maker of a weight-loss drug that took off and went bust in the "fen-phen" craze must face claims that its warning labels were inadequate, the Pennsylvania Supreme Court ruled.
Patsy Lance, representing the estate of Catherine Ruth Lance, brought the product liability lawsuit in question against Delaware-based Wyeth, formerly known as American Home Products.
Wyeth manufactured Pondimin and Redux, which weight-loss clinics prescribed in the mid-1990s. Combined with phentermine, Pondimin (fenfluramine) gave rise to the nickname "fen-phen."
The Food and Drug Administration approved Redux with a warning that its use could lead to pulmonary hypertension, but Pondimin and Redux were taken off the market by 1997 as reports about the risk of heart problems grew.
Lance's lawsuit is one of thousands that accuse Wyeth of "unreasonable marketing of a dangerous drug and unreasonable failure to remove the drug from the market before January 2007."
A judge in Philadelphia dismissed Lance's case, however, after finding that a seller cannot be held liable without proof of an impurity or an inadequacy in labeling.
An appellate panel revived Lance's negligent design defect claim, leading both sides to seek relief from the Pennsylvania Supreme Court.
In a partial reversal last week, the state's high court said, 4-2, that Lance may also have a case for negligent marketing.
"A company which is responsible for tendering into the market a drug which it knows or should know is so dangerous that it should not be taken by anyone can be said to have violated its duty of care either in design or marketing," Justice Thomas Saylor wrote for the majority.
"In other words, in the negligence area at least, the substantive allegations are more important than the labels," he added.
Justice J. Michael Eakin wrote the dissent.
"Appellee did not raise 'negligent design defect' in her Rule 1925(b) statement," he said. "She did not include such a claim in her Superior Court of Statement of Questions Involved, which specifically concern 'negligent marketing' and 'failure to withdraw' claims, and nothing more."
Eakin added: "This court should wait for a full, developed record on a properly preserved claim, in order that we may consider advocacy on both sides expressing the various incentives and disincentives created by changing this area of products liability law."
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