Seizures during pegylated interferon and ribavirin therapy for chronic Hepatitis C: observations from the WIN-R trial.

BACKGROUND: Seizures are reported as an uncommon side effect of interferon therapy. AIM: To determine the frequency and presentation of seizures occurring during pegylated interferon-α (PEG-IFNα) and ribavirin therapy for chronic hepatitis C. METHODS: Patients were identified using data from the WIN-R trial database, a US multicenter study comparing fixed (800 mg) versus weight-based (800 to 1400 mg) daily dosing of ribavirin in combination with PEG-IFNα-2b (1.5 µg/kg/wk). RESULTS: Of the 4913 enrolled patients, 8 (0.16%) had a seizure. Three patients had a grand mal seizure and the seizure type was unknown in 5 patients. At the time of seizure, 6 patients were taking antidepressants (including 3 on bupropion), 1 was hyponatremic, and 1 had consumed a significant amount of alcohol. One patient had a history of seizures. Neuroimaging and electroencephalographic studies were negative. Antiepileptic medications were continued in the patient with a history of seizures and initiated in 1 patient. PEG-IFNα-2b plus ribavirin therapy was continued in 2 patients following seizure and neither experienced a recurrent seizure. CONCLUSIONS: Seizures occur infrequently in patients receiving PEG-IFNα-2b plus ribavirin, and appear to be associated with other risk factors including antidepressant use.

Impact of weight-based ribavirin with peginterferon alfa-2b in African Americans with hepatitis C virus genotype 1.

UNLABELLED: WIN-R (Weight-based dosing of pegINterferon alfa-2b and Ribavirin) was a multicenter, randomized, open-label, investigator-initiated trial involving 236 community and academic sites in the United States, comparing response to pegylated interferon (PEG-IFN) alfa-2b plus a flat or weight-based dose of ribavirin (RBV) in treatment-naive patients with chronic hepatitis C and compensated liver disease. Patients were randomized to receive PEG-IFN alfa-2b at 1.5 microg/kg/week plus flat-dose (800 mg/day) or weight-based-dose RBV (800 mg/day for weight <65 kg, 1000 mg/day for 65-85 kg, 1200 mg/day for >85-105 kg, or 1400 mg/day for >105-<125 kg). Sustained virologic response (SVR; undetectable [<125 IU/mL] hepatitis C virus [HCV] RNA at end of follow-up) in patients > or =65 kg was the primary end point. Low SVR rates have been reported among African American individuals, in whom there is a preponderance of HCV genotype 1. This subanalysis of WIN-R was conducted to evaluate the efficacy of weight-based dosing among African American individuals with genotype 1 infection enrolled in the trial. Of 362 African American patients in the primary efficacy analysis, 188 received RBV flat dosing and 174 received weight-based dosing. SVR rates were higher (21% versus 10%; P = 0.0006) and relapse rates were lower (22% versus 30%) in the weight-based-dose group than in the flat-dose group. Safety and rates of drug discontinuation were similar between the 2 groups. CONCLUSION: Weight-based dosing of RBV is more effective than flat dosing in combination with PEG-IFN alfa-2b in African American individuals with HCV genotype 1. Even with weight-based dosing, response rates in African American individuals are lower than reported in other ethnic groups.