Study objective: To investigate the adverse drug reactions (ADRs) from peginterferon alfa-2b plus ribavirin in patients infected with the hepatitis C virus (HCV).
Design: Prospective, observational, pharmacovigilance study.
Setting: Gastroenterology department of a French university hospital.
Patients: A cohort of consecutive outpatients who were treated with peginterferon alfa-2b plus ribavirin for viral hepatitis.
Intervention: During the 1-year period of HCV therapy visits, a medical staff member trained in pharmacovigilance interviewed the patients about all ADRs and their use of other drugs. The ADRs assessed as serious were confirmed from regular review of the medical records.
Measurements and main results: A total of 87 patients were treated for HCV. Among these, peginterferon alfa-2b plus ribavirin therapy was started in 51 patients; one patient was lost to follow-up after 1 month. The ADRs were assessed as serious in 10 patients (20%): suicide (one patient), hospitalization (three patients), and definitive discontinuation of peginterferon alfa-2b plus ribavirin (six patients). The ADRs contributed to or were the main reason for withdrawing HCV drugs in 8 patients (16%). Dosage reductions of ribavirin and/or peginterferon alfa-2b were required in 10 patients (20%) and seemed less frequent than that needed in clinical trials. Compared with results of clinical trials, a similar frequency of hair loss, higher frequency of injection-site reactions, lower frequency of depression or insomnia, and higher frequency of endocrine ADRs or blurred vision were detected.
Conclusion: Results suggest some differences in the frequencies of ADRs compared with data from clinical trials. A longer period of monitoring is warranted to improve knowledge about ADRs of pegylated interferon. A medical staff member trained in pharmacovigilance is useful to collect quantitative and qualitative data about ADRs.