The roadmap concept suggests the use of on-treatment HBV DNA to guide treatment strategy of chronic hepatitis B patients treated by telbivudine. Our aim was to validate the roadmap approach of entecavir switch therapy in patients with incomplete response to telbivudine.
Consecutive chronic hepatitis B patients on telbivudine monotherapy were studied. Incomplete virologic response was defined as detectable HBV DNA after 6-12 months of treatment. Maintained virologic response was defined as undetectable HBV DNA till last follow-up.
Among 79 patients on telbivudine, 39 (49%) had undetectable HBV DNA after 6-12 months of telbivudine treatment and 40 (51%) had incomplete virologic response. Thirty-three incomplete responders switched to entecavir at 11 (6-23) months and 26 (79%) achieved maintained virologic response after 25 (4-46) months. Low HBV DNA level before switch therapy was the independent factor associated with maintained virologic response to entecavir (p = 0.01). Twenty-four of 25 (96%) patients with HBV DNA <2000 IU/ml versus 2 of 8 (25%) patients with HBV DNA ≥2000 IU/ml had maintained virologic response after switching to entecavir. While rtM204I and/or rtL180M was detected in 3 of 7 patients with incomplete virologic response to entecavir, none of the patients with HBV DNA <2000 IU/ml during telbivudine treatment harbored these amino acid substitutions.
Roadmap approach using entecavir switch at month 6-12 among incomplete responders to telbivudine is recommended if the HBV DNA is <2000 IU/ml at the time of switching.