Baseline CD4+T-Cell Counts Predict HBV Viral Kinetics to Adefovir Treatment in Lamivudine-Resistant HBV-Infected Patients with or without HIV Infection

Background: Coinfection with HIV and hepatitis B virus (HBV) substantially alters the course of HBV. Directly acting anti-HBV agents suppress HBV viral levels; however, the kinetics of HBV decline in mono- and coinfected persons have not been evaluated. We investigated the role of baseline CD4+ T-cell counts as a predictor of HBV response to adefovir (ADV) therapy in chronic HBV with and without HIV coinfection. Methods: We conducted a double-blind, randomized, placebo-controlled study of HIV-infected (n = 12) and uninfected (n = 5) chronic HBV patients treated with ADV. Five HIV uninfected patients received ADV; the HIV+ patients received ADV or placebo for a total of 48 weeks. At the end of 48 weeks, all patients received open-label ADV for an additional 48 weeks. HBV, HIV viral loads, CD4+ T-cell counts, and safety labs were performed on days 0, 1, 3, 5, 7, 10, 14, and 28 and then every 4 weeks. Results: Lower HBV slopes were observed among coinfected compared to monoinfected patients (P=.027 at 4 weeks, P=.019 at 24 weeks, and P=.045 at 48 weeks). Using a mixed model analysis, we found a significant difference between the slopes of the 2 groups at 48 weeks (P=.045). Baseline CD4+ T-cell count was the only independent predictor of HBV decline in all patients. Conclusion: HIV coinfection is associated with slower HBV response to ADV. Baseline CD4+ T-cell count and not IL28B genotype is an independent predictor of HBV decline in all patients, emphasizing the role of immune status on clearance of HBV.