In a defeat for drug maker Wyeth, the court let stand a lower ruling that a federal judge went too far when he issued an order restricting the evidence. The Philadelphia judge reasoned that the diet drug users had violated a $3.75 billion settlement agreement with the Madison, N.J.-based company.

In legal filings, Wyeth argued that former users of its Pondimin and Redux pills violated the agreement not to seek punitive damages when they chose to "opt out" of the federal class-action settlement to pursue their own lawsuits.

The judge properly barred the plaintiffs from using evidence in state court such as those suggesting Wyeth placed marketing ahead of health and safety concerns, because the evidence might encourage juries to award punitive damages, the company argued.

The 3rd U.S. Circuit Court of Appeals disagreed in ruling that the judge's order improperly limited evidence that could help plaintiffs prove their injury. The federal judge's action also didn't properly consider the rights of state courts since the lawsuits were being heard there, the 3rd Circuit said.

Wyeth pulled Pondimin and Redux, the fenfluramine half of fen-phen, from the market in September 1997 amid reports some users had heart valve damage and a few had a deadly lung condition. Fen-phen was never an FDA-approved combination, and the phentermine half is still sold.

The Supreme Court's action Monday means that plaintiffs will now be able to present evidence previously barred, but they still may not use those that are relevant only to a claim for punitive damages.