Low five-year resistance for Baraclude

US drug major Bristol-Myers Squibb says that new data on its drug Baraclude (entecavir) demonstrate a continued low incidence of resistance in nucleoside-naive patients through five years of treatment. In the chronic hepatitis B patients analyzed, no additional patient developed resistance in the fifth year, according to data presented at the the 18th Conference of the Asia-Pacific Association for the Study of the Liver, held in Seoul, Korea.

Through five years of treatment, the cumulative probability of developing mutations in the virus that confer resistance to Baraclude (also called genotypic resistance) was 1.2%. In lamivudine-refractory patients who received Baraclude after treatment with lamivudine failed, the cumulative probability of genotypic Baraclude resistance was 51% through the fifth year. This finding is consistent with prior observations that the pre-existence of lamivudine-resistant mutations results in a greater rate of Baraclude resistance, noted the firm. "Many chronic hepatitis B patients require long-term treatment. Unfortunately, the initial benefits of therapy can be lost after the development of resistance," said Ching-Lung Lai of the University of Hong Kong.