VESNARINONE INDUCED GRANULOCYTOPENIA - INCIDENCE IN JAPAN AND RECOMMENDATIONS FOR SAFETY

Vesnarinone (OPC-8212) is a new positive inotropic agent that augments myocardial contractility. A recent multi-center randomized trial in t he United States demonstrated that 60 mg/day of vesnarinone significan tly reduced morbidity and mortality and improved quality of life in pa tients with symptomatic chronic heart failure. Vesnarinone, however, i s also known for its propensity to cause granulocytopenia. In search o f effective safety measures against this side effect, data have been c ollected in Japan as part of the post marketing surveillance of this d rug. This article reviews the results of this post-marketing surveilla nce and other works available to date, including an illustrative case report, and presents measures that should be token with regard to safe ty during treatment with vesnarinone. Vesnarinone-induced granulocytop enia has appeared in relatively early stages of vesnarinone therapy, a nd characteristically results in a rapid decrease in granulocyte count . Hematologic monitoring should be performed at least once a week duri ng the initial 16 weeks of vesnarinone therapy. Granulocyte colony-sti mulating factor may con tribute to recovery from severe granulocytopen ia, although it should be used carefully because of its potential to c ause adult respiratory distress syndrome.