Warnings Increase for Antiretroviral Drug
Roxane Laboratories Inc. has revised the product labeling for nevirapine to strengthen warnings about the risk of hepatotoxicity from use of the antiretroviral agent.
In a letter (PDF) sent this month to health care professionals, the company, a subsidiary of Boehringer Ingelheim Corp., said it continues to receive reports of severe, sometimes fatal, cases of hepatotoxicity in association with nevirapine, or Viramune, use. Analysis of the reports led the company to declare the first 12 weeks of therapy as a "critical period during which intensive clinical and laboratory monitoring, including liver function tests, is essential to detect potentially life-threatening hepatotoxicity."
Fatigue, malaise, anorexia, and nausea, but not necessarily abnormal levels of serum transaminases, often signaled the onset of hepatotoxicity, the company stated. Although Roxane urges health care professionals to carefully monitor patients for signs and symptoms of hepatotoxicity during the first 12 weeks of therapy, the company also noted that about one third of the cases occurred after that critical period.
Serious skin rashes have also developed during nevirapine therapy. Part of the product's labeling have been revised to stress the importance of starting therapy in adults at 200 mg/day for 14 days and then, if a rash does not appear, increasing to the maintenance dosage of 200 mg twice daily. On the basis of results from a clinical trial, described in the revised product labeling, the company does not recommend the use of prednisone to prevent rashes during nevirapine therapy.