Two-year treatment outcome of chronic hepatitis B infection treated with besifovir vs. entecavir: Results from a multicentre study

Background & Aims We aimed to compare the viral suppression, safety and rate of drug resistance between besifovir (a new acyclic nucleotide analogue) and entecavir. Methods Treatment-naïve chronic hepatitis B patients receiving besifovir 90 mg (n = 31), 150 mg (n = 28) and entecavir 0.5 mg (n = 30) were monitored for liver biochemistry, viral serology, HBV DNA levels, development of drug resistance mutations, and adverse events throughout 96 weeks of treatment. Results The mean decline of HBV DNA levels from baseline to week 96 were 5.29, 5.15, and 5.67 logs IU/ml for patients receiving besifovir 90 mg, 150 mg and entecavir 0.5 mg, respectively (p >0.05). Undetectable HBV DNA (<20 IU/ml) were achieved in 80.7%, 78.6%, and 80%; ALT normalization in 90.3%, 78.6%, and 93.3%; and loss of HBeAg in 20%, 21.4%, and 22.2% of patients respectively (all p >0.05). One patient receiving besifovir 90 mg had a virological breakthrough due to drug non-compliance. No patient developed drug resistance mutations. Ten patients had serious adverse events, which were not related to the study medications. The most common side effect related to besifovir was carnitine depletion. Carnitine supplements were prescribed to 83.9% and 100% of patients, who had low carnitine level for any one time during follow-up, receiving besifovir 90 mg and 150 mg respectively. No patient had increased creatinine >0.5 mg/dl from baseline. Conclusions Besifovir had the same antiviral property as compared to entecavir over 96 weeks of treatment for chronic hepatitis B patients. Besifovir was well tolerated and also had a good clinical safety profile.