Judge won't let Pfizer rid itself of inherited fen-phen scourge

Pfizer just can't get rid of the specter of fen-phen. Fifteen years after the diet drug was removed from the market over serious health concerns, litigation lingers and the drugmaker's move to kill that off fell short yesterday.

Pfizer ($PFE) has reserved $21 billion for fen-phen litigation over the years but hoped to have remaining suits dismissed. But a judge in Philadelphia, where most of the suits are consolidated, wasn't buying it. He said plaintiffs can use studies from experts that indicate that fen-phen can instigate primary pulmonary hypertension, even more than a decade after consumers stopped taking the appetite suppressant. Pfizer tells Bloomberg that it is weighing its legal options.

Pfizer bought the problem when it acquired the drug's developer Wyeth in 2009, 12 years after fen-phen was banned in the U.S. More than 6 million prescriptions had been written when it was on the market, Bloomberg says, and at one time there were more than 175,000 claims that the combo diet drug had caused health problems, sometimes leading to early deaths.

Wyeth originally set up a $1.3 billion fund in 2004 to cover the potential losses, but over the years that escalated as litigation and potential liability grew. By the time Pfizer entered the picture, the fund was at $21.1 billion.

Of course, lingering litigation is common to many drugmakers. Pfizer in June, for example, reported in a financial filing that it had paid out nearly $900 million on about 6,000 injury cases related to the hormone replacement Prempro and had set aside another $330 million for the remaining 4,000 cases. Before that, it was settling litigation for its Celebrex pain drug. The pool of funds set aside for fen-phen cases, and the number of years the cases have been kicking around, place fen-phen in an entirely different class.

- here's the Bloomberg story