FDA issues public health advisory for Pfizer's Trovan

Following post-marketing reports of hepatotoxic events leading to asmall number of liver transplants and deaths, the US Food and Drug Administration has issued an interim public health advisory to physicians outlining the risks associated with Pfizer's broad-spectrum fluoroquinolone antibiotic Trovan/Turvel (oral trovafloxacin/intravenous alatrofloxacin), prior to approval of revised labeling.

In the advisory, the FDA states that Trovan should be reserved for patients who meet certain defined criteria, which include specified infections deemed to be life- or limb-threatening. It adds that Trovan therapy should not be continued for longer than 14 days and should be discontinued if the patient experiences clinical signs of liver dysfunction. Meantime, Pfizer has agreed to limit distribution to hospitals and long-term nursing care facilities. In a statement, the company said it had a "difference of opinion with the agency over the interpretation of these data [see later] and the regulatory action being taken." It adds that the "risk assessment requires additional scientific evaluation and analysis in order to provide physicians with the proper clinical guidance."

Since its launch in February 1998, about 2.5 million prescriptions have been written for Trovan with 140 documented cases of serious adverse liver reactions reported. A statement from the European Medicines Evaluation Agency on May 26 noted five deaths and three liver transplants in patients taking Trovan (Marketletter May 31), however the FDA says that it is now aware of 14 cases of acute liver failure which "are strongly associated with the drug." The EMEA's next round of discussions was due to take place on June 10-11, after the Marketletter went to press, according to a company spokesman.