HOECHST-ROUSSEL MERITAL (NOMIFENSINE) WORLDWIDE MARKET WITHDRAWAL FOLLOWS REPORTED INCREASE IN INCIDENCE OF SEVERE HEMOLYTIC ANEMIA ADVERSE REACTIONS

Hoechst-Roussel's Merital (nomifensine maleate) worldwide voluntary recall is being initiated because of reports of an increasing number of hemolytic anemia adverse reactions. In a Jan. 22 press release, the firm announced that the antidepressant is being withdrawn by the Hoechst Group worldwide "as a precautionary measure, based on recent reports about an increasing number of hypersensitivity reactions to nomifensine in Great Britain." Nomifensine, first approved for use in Europe in 1976, and most recently approved by FDA in December 1984, is currently used in 80 countries. Hoechst said that in 10 years of marketing experience, in which 14 mil. patients have been treated with the drug, the incidence of hemolytic anemia has remained relatively stable at about one in 300,000. The firm indicated that while the recent U.K. reports of the reaction do not greatly exceed the 10 year incidence rate, the parent company in Germany made the decision to halt distribution worldwide because a number of cases were reported in a short period of time. The exact number of hemolytic anemia reactions in Great Britain has not been disclosed. Hoechst said it made the decision to withdraw the product on Jan. 20, and stopped production and distribution on the same day. The firm notified FDA of its planned course of action Jan. 21, and proceeded to inform distributors by phone and telegram to discontinue sales of nomifensine Jan. 22. The firm also notified doctors and pharmacists of the market withdrawal by letter. The "Dear Doctor" letter states: "We have been informed of an increase in the number of reports of serious hypersensitivity reactions, notably hemolytic anemia, occurring in nomifensinetreated patients in the United Kingdom. Although our current package literature notes these side effects, as a precautionary measure Merital is immediately being withdrawn from sale in the U.S. and on a worldwide basis." The letter directs doctors to "please discontinue the administration of Merital immediately and transfer patients, if appropriate, to alternative therapy." Hoechst notes that "we deeply regret this development, however, our responsibility as an ethical pharmaceutical manufacturer requires that we voluntarily take this action." Merital labeling warns that "cases of severe hemolytic anemia resulting in fatalities have been reported. . . The sequalae of hemolytic anemia are potentially life threatening and can lead to renal complications (acute renal failure). Accordingly, before initiating or reinitiating Merital treatment, a blood count . . . should be obtained for a baseline and to exclude hemolytic anemia. Blood counts should be repeated periodically during treatment. If anemia develops at any point during treatment, Merital should be discontinued, the cause of anemia established, and appropriate treatment instituted." According to Hoechst, 15 patients have died from hemolytic anemia during nomifensine's marketing history. The 15 deaths, Hoechst reported, all occurred in cases where physicians did not test for the blood abnormality.