Post-marketing surveillance for the safety and effectiveness of adefovir in patients with chronic hepatitis B

Abstract

Background: To investigate the safety and effectiveness of adefovir in Korean patients with chronic hepatitis B, an observational study was carried out. Methods: A total of 4,393 patients with chronic hepatitis B were enrolled from February 2004 to February 2010. For the safety assessment, investigators recorded the occurrence of observed and patient-reported adverse events (AEs) throughout the course of treatment. Antiviral effectiveness was assessed by measuring the degree of symptom improvement and the reduction of HBV DNA after 12 weeks of treatment. Results: Of the 4,393 patients, 4,158 patients were evaluated for safety and 3,867 patients for effectiveness assessment. A total of 118 AEs were reported in 4,158 patients (1.8 %). The most frequent AE was hepatic failure (0.2 %) followed by coughing (0.2 %), hepatic neoplasm (0.2 %), abdominal pain (0.1 %), dyspepsia (0.1 %), nausea (0.1 %), flatulence (0.1 %), hepatic cirrhosis (0.1 %), asthenia (0.1 %), increase in sputum production (0.1 %), and varicose vein (0.1 %). The incidence of unexpected AEs was 0.9 %. Forty-nine cases of serious AE were reported in 32 patients but all of those were thought to be unrelated to adefovir according to physician's evaluations. The rate of subjects with well effectiveness was 96.2 %. Conclusion: Adefovir was clinically well tolerated and effective in treatment of chronic hepatitis B patients.