Clinical Course of Partial Virologic Response with Prolonged Tenofovir Therapy in Nuclos(t)ides-Naïve Patients with Chronic Hepatitis B

Background/Aims The clinical course of chronic hepatitis B (CHB) patients with partial virologic response (PVR) during tenofovir disoproxil fumarate (TDF) therapy remains unclear. Methods We retrospectively investigated the long-term clinical outcomes of TDF treatment in nucleos(t)ides-naïve CHB patients, particularly in those with PVR. Results A total of 391 patients treated with TDF therapy for more than 12 months were included. Virologic response (VR) was achieved in 341 patients (87.2%). PVR was evident in 127 (45.3%) of the 391 patients. Multivariate logistic regression analysis using selected baseline factors identified absolute HBV DNA levels at baseline (OR 0.496; 95% CI 1.369–1.969) and HBeAg positivity (OR 0.622; 95% CI 1.096–3.167) as factors significantly associated with PVR. During continuous prolonged TDF therapy, 127 (71.8%) of 177 patients with PVR achieved VR. The cumulative rates of VR in patients with PVR at 12, 24, and 36 months were 42.4, 79.7, and 90.2%, respectively. Serum HBV DNA level at week 24 was significantly associated with VR in patients with PVR. Conclusions The vast majority of CHB patients with PVR achieved VR through prolonged TDF therapy, although the time to achieve VR was delayed in those with PVR. This suggests that adjustment of TDF therapy in patients with PVR is unnecessary.