TDF Monotherapy Effective as TDF-Based Combo Therapy in HBV

SAN FRANSCICO, CATenofovir disoproxil fumarate (TDF) rescue monotherapy achieves complete virological response (CVR) rates at 48 and 96 weeks similar to those of tenofovir-based combination rescue therapy in patients with chronic hepatitis B virus (HBV) infection, even in patients with multi-drug resistance, investigators reported during The Liver Meeting® 2015.

“There is no significant difference of complete virological response between patients with TDF monotherapy and those with TDF-based combination therapy,” reported Kyu Sik Jung, MD, Department of Internal Medicine, Yonsei University College of Medicine, in Seoul, Korea, and colleagues. “This data suggested that TDF monotherapy is a useful rescue therapy in chronic hepatitis B with resistance to antiviral agents, including multidrug-resistant strains.” 

The presentation detailed interim results of multicenter cohort study in 847 consecutive patients with chronic HBV treated with tenofovir monotherapy (n=546) or tenofovir-based combination therapy (tenofovir plus entecavir, lamivudine, or telbivudine; n=301) as rescue therapy for resistance to antiviral agents, noted Dr. Jung. 

Complete virological response (CVR) was defined as undetectable serum HBV-DNA (detection limit 20 IU/mL) and biochemical response was defined as normalization of serum alanine aminotransferase (ALT) level. At the time of rescue therapy initiation, median serum HBV DNA level was 3.6 log IU/mL among monotherapy patients and 3.7 log IU/mL among TDF-based combination therapy patients. Baseline ALT levels were 50 and 52.2 IU/mL, respectively.

The cumulative incidence of CVR among patients in the monotherapy and combined-therapy groups were similar overall (95.8% and 94.5%, respectively) and among patients with multidrug-resistant infections (95.5% and 94.0%, respectively), the researchers reported. The cumulative HBeAg seroconversion rates at 48 and 96 weeks were comparable between patients in the monotherapy and combination therapy groups.

However, at both 48 and 96 weeks, mean HBV-DNA reduction was significantly higher in patients receiving tenofovir-based combination therapy than among those receiving tenofovir monotherapy (P<0.05), the researchers noted. 

“Further studies with a longer follow-up are required to validate these results,” Dr. Jung concluded.