Studies indicate that 70% to 80% of HIV infected patients have or have had HBV infection and that 10% are HBV carriers. Lamivudine therapy for treatment of HBV in HIV infected patients has limited long-term efficacy due to the development of resistance mutations. Telbivudine is a thymidine analogue with excellent HBV inhibitory activity but no anti-HIV activity. The primary objective of this study is to evaluate the safety and anti-HBV activity of telbivudine alone and in combination with a lamivudine-based highly active antiretroviral therapy (HAART) regimen in patients coinfected with HBV and HIV.
Patients in this study will take telbivudine for 24 weeks. At Week 24, patients will add a HAART regimen containing lamivudine and efavirenz plus either didanosine or abacavir. Patients who are unable to add a HAART regimen at Week 24 due to lab abnormalities or other contraindications will be allowed to delay the initiation of HAART until Week 30. Patients may initiate HAART prior to Week 24 if deemed medically necessary by the primary HIV care provider. Patients will take both telbivudine and HAART for 24 weeks. At Week 48, patients will discontinue telbivudine and continue on the HAART regimen alone for an additional 12 weeks.