Long-Term Treatment Efficacy and Safety of Clevudine Therapy in Naïve Patients with Chronic Hepatitis B

BACKGROUND/AIMS Clevudine (CLV) has potent antiviral activity against chronic hepatitis B (CHB) virus infection. The long-term efficacy and safety of CLV therapy in naïve patients with CHB were investigated. METHODS In this retrospective study, 152 naïve Korean patients with CHB who received 30 mg of CLV once daily for at least 12 months were investigated. RESULTS The cumulative rates at months 12, 24, and 36, respectively, were 65.8%, 74.7%, and 74.7% for undetectable serum hepatitis B virus (HBV) DNA (<12 IU/mL); 77.6%, 86.2%, and 86.2% for normalization of serum alanine aminotransferase (<40 IU/L); 17.6%, 23.5%, and 23.5% for hepatitis B e antigen (HBeAg) loss or seroconversion; and 6.6%, 22.5%, and 30.0% for viral breakthrough. HBeAg positivity (p=0.010), baseline serum HBV DNA level ≥6 log(10) IU/mL (p=0.032) and detectable serum HBV DNA (≥12 IU/mL) at week 24 (p=0.023) were independently associated with the development of viral breakthrough. During follow-up, CLV-induced myopathy developed in 5.9% of patients. CONCLUSIONS The results of long-term CLV therapy for the treatment of naïve patients with CHB showed a high frequency of antiviral resistance and substantial associated myopathy. Therefore, we advise that CLV should not be used as a first-line treatment for naïve patients given the availability of other more potent, safer antiviral agents.