Introduction. Lamivudine was widely used to treat chronic hepatitis B due to its’ low price and availability in the past. Due to fast evolving of resistance, lamivudine is not recommended as first treatment choice anymore; however it was noticed that patients, who previously developed resistance to lamivudine, also develop resistance to entecavir.
Aim of the Study. To assess data of chronic hepatitis B patients’, treated with any kind of antiviral therapy. To assess efficacy of entecavir, rates of developing drug resistance between Lamivudine-naive and experienced patients.
Methods. A retrospective research included patients currently on treatment, who were followed-up in VUHSK Centre of Infectious diseases and treated with entecavir for at least 12 months. Patients were divided into two groups: 1 - lamivudine-naive, 2 - lamivudine-experienced. Anonymous patients’ data were evaluated performing descriptive statistical analysis. Literature was collected using PubMed, UpToDate and MEDLINE search systems.
Results. Of all 122 patients currently receiving antiviral treatment 35% (N=43) were female, mean age was 45.4±14.4 years. 69% (N=84) of the patients were treated with entecavir monotherapy. The final sample consisted of 59 patients: 21 lamivudine-naive and 38 lamivudine-experienced. In aforementioned group 87% (N=33) had previously developed resistance to lamivudine. Resistance to entecavir was observed only in lamivudine resistant patients after 38.4±25.2 months of therapy and reached 24% (N=9).
Conclusions. Lamivudine exposed patients had a greater risk in developing resistance to entecavir, therefore aforementioned patients should receive tenofovir therapy, for which cross-resistance is not characteristic.