Entecavir Alone Works as Well as Combo for First-time Hepatitis B Treatment


Treating chronic hepatitis B with entecavir (Baraclude) alone worked as well as dual therapy using entecavir plus tenofovir (Viread) for patients starting treatment for the first time, according to a study described in the September 2012 issue of Gastroenterology.

Several nucleoside/nucleotide analogs are active against hepatitis B virus (HBV), but the virus can develop resistance to these drugs -- especially when they are used alone -- which may compromise long-term treatment success. Resistance develops rapidly with lamivudine (3TC; Epivir), the old standard of care, but some newer drugs have a higher barrier to resistance.

Anna Lok from the University of Michigan Health System and fellow investigators with the international BE-LOW study (ETV-110) compared the safety and efficacy of entecavir monotherapy versus a combination of entecavir plus tenofovir for chronic hepatitis B.

This open-label multicenter study included 379 patients not previously treated with nucleoside/nucleotide analogs. About 70% were men and the average age was 40 years; approximately half were white and half Asian. About 70% were hepatitis B "e" antigen (HBeAg) positive, the rest HBeAg negative. At baseline the average HBV viral load was 7.5 log IU/mL.

Participants were randomly assigned to receive 0.5 mg once-daily entecavir either alone or in combination with 300 mg once-daily tenofovir for 100 weeks. The primary endpoint was the proportion of patients with undetectable HBV DNA (< 50 IU/mL) at week 96.


"The antiviral efficacy of entecavir monotherapy is comparable to that of entecavir plus tenofovir in a mixed population of [nucleoside/nucleotide]-naive patients with chronic hepatitis B," the study authors concluded. "The combination therapy could provide an incremental benefit to HBeAg-positive patients with baseline levels of HBV DNA > 108 IU/mL."



AS Lok, H Trinh, G Carosi, et al. Efficacyof Entecavir With or Without Tenofovir Disoproxil Fumarate for Nucleos(t)ide-Naive Patients With Chronic Hepatitis B. Gastroenterology 143(3):619-628.e1. September 2012.