Therapy with entecavir and tenofovir was similarly as effective as entecavir alone in patients with chronic HBV, but improved response among hepatitis B e antigen-positive patients with higher baseline HBV DNA levels in a recent study.
In an open-label, multicenter superiority study, researchers randomly assigned 379 nucleos(t)ide-naive patients with chronic HBV either 0.5 mg entecavir (ETV) (n=182) or 0.5 mg ETV with 300 mg tenofovir disoproxil fumarate (TDF) (n=197) for 100 weeks. The cohort included 264 hepatitis B e antigen-positive (HBeAg-positive) and 115 HBeAg-negative patients. Primary endpoint was an HBV DNA level less than 50 IU/mL.
The proportion of patients reaching the primary endpoint was similar between groups after 96 weeks (83.2% receiving combination therapy vs. 76.4% receiving ETV alone; P=.088). Rate of response was similar among HBeAg-negative patients in the two groups (89.8% for HBeAg-negative patients receiving combination therapy, 91.1% for those receiving ETV alone; P=.82). ALT level normalization occurred more frequently in the monotherapy group at 96 weeks (81.9% of patients vs. 69.0%; P=.004).
A significantly larger number of HBeAg-positive patients receiving combination therapy (80.4%) achieved the endpoint than HBeAg-positive patients receiving ETV alone (69.8%) (P=.046 for difference), but the difference only occurred among patients with baseline DNA levels of 108 IU/mL or greater: In this subgroup, more patients receiving combination therapy achieved the endpoint (78.8% vs. 62.0%; P=.018), but rates were similar among patients with levels less than 108 IU/mL (83.0% for both treatment methods). The proportion of HBeAg-positive patients achieving seroconversion (P=.08) and loss (P=.16) were similar between groups.
The mean change to HBV DNA levels from baseline was similar at 96 weeks between groups (–5.96 log10 IU/mL for combination therapy vs. –5.7 log10 IU/mL for ETV monotherapy; P=.25), but HBeAg-positive patients in the combination therapy group experienced a larger change (–6.62 log10 IU/mL for combination vs. –6.30 log10 IU/mL for monotherapy; P=.04).
“Over 96 weeks of treatment, the antiviral efficacy of ETV monotherapy is similar to that of ETV plus TDF combination therapy in a mixed population of NA-naive patients with [chronic HBV],” the researchers concluded. “Evaluation of the combination of ETV plus TDF beyond 96 weeks is necessary to confirm its safety and efficacy during long-term use.”
Disclosure: See the study for a full list of relevant disclosures.