Data presented Monday by drugmaker Bristol-Myers Squibb at the 55th Annual Meeting of the American Association for the Study of Liver Diseases in Boston shows that the experimental drug entecavir is more effective in treating hepatitis B than the antiretroviral Epivir (3TC). Entecavir was shown in two studies to both improve liver function and lower blood-based hepatitis B virus levels, outperforming Epivir therapy. Patients studied had chronic HBV infection and included both those who were HBV treatment-naive and others who had been treated with and developed resistance to Epivir. After 48 weeks of entecavir therapy, 70% of treatment-naive patients showed liver function improvement, compared with 61% of patients who began Epivir treatment. Undetectable HBV levels were seen in 91% of the treatment-naive patients who began entecavir therapy after 48 weeks, compared with 73% of those taking Epivir. A study of treatment-experienced patients showed that those switched from Epivir to entecavir had significantly higher improvements after 48 weeks in liver clinical measurements and had better viral suppression than those who continued taking Epivir.
Entecavir is currently in Phase III clinical tests. Bristol-Myers Squibb recently submitted a new drug application for the medication to the U.S. Food and Drug Administration and a marketing authorization application to the European Medicines Evaluation Agency. More than 2 billion people worldwide have been infected with HBV; 350 million to 400 million are chronically infected and are at high risk of liver damage, liver cancer, and death. HBV can be transmitted sexually and is a common sexually transmitted disease among gay and bisexual men. The Gay and Lesbian Medical Association recommends that all sexually active gay and bisexual men be vaccinated against both hepatitis A and B. Fewer than half of sexually active U.S. gay men have been vaccinated, according to GLMA.