Analogs in the treatment of chronic hepatitis B: real life experience with tenofovir and entecavir

INTRODUCTION: Tenofovir and entecavir are potent antiviral agents. By suppressing viral replication, they induce histological improvement and finally delay the progression of chronic hepatitis B and the development of complications. They are rarely associated with serious side effects. Our data from a real life experience support data from the literature and suggest some minimal difference that may be useful in tailoring therapy. PATIENTS AND METHODS: We retrospectively analyzed 54 patients affected by chronic hepatitis B (31 and 23 treated by entecavir and tenofovir, respectively). Eight patients were cirrhotic. At baseline and 4-12 and 24 weeks after starting therapy, biochemical and virological analysis were performed in all patients. Renal function tests (serum creatinine, creatinine clearance and blood urea), serum (calcium and phosphate blood level) and urine electrolyte were also studied. RESULTS: All the patients reached virological control within 24 weeks. Only in the group treated by tenofovir we observed a complete viral suppression within 12 weeks. Some patients treated with tenofovir showed increased creatinine clearance without serum creatinine alteration. No significant side effects were reported with the exception of one case of persistent headache in the entecavir group for which the drug was suspended. CONCLUSIONS: Entecavir and tenofovir are effective in suppressing viral replication in patients with chronic hepatitis B. Tenofovir is more potent than entecavir and viral replication is blocked within 12 weeks of therapy. Tenofovir administration is associated with slight increase of creatinine clearance without alteration of serum creatinine levels. The choice of one or the other should be made according to target and specific patients characteristics. In patients with high serum viral load where the complete and quick control of viral replication is the main target, tenofovir may represent the best choice