Adefovir Salvage Effective for HBV Recurrence in Lamivudine-Treated Patients

NEW YORK (Reuters Health) Feb 10 - In liver transplant recipients with hepatitis B virus who develop lamivudine resistance, add-on therapy with adefovir is effective for salvage, according to a report in the February Journal of Medical Virology.

"In countries where hepatitis B immune globulin (HBIg) is too expensive, lamivudine monoprophylaxis and adefovir salvage for resistance can be considered for liver transplantation," Dr. Henry L. Y. Chan from The Chinese University of Hong Kong told Reuters Health. "For patients with detectable HBV DNA at the time of liver transplantation, the risk of lamivudine resistance is higher, and HBIg or a more potent antiviral agent should be considered."

In 24 patients who underwent liver transplantation for HBV, Dr. Chan and his colleagues studied the incidence and clinical course of lamivudine resistance and the response of lamivudine-resistant HBV to adefovir salvage.

Seven patients developed lamivudine resistant HBV mutants. Detectable HBV DNA and positive hepatitis B e antigen prior to transplant were associated with HBV recurrence, the researchers note.

All seven patients were treated with adefovir, 10 mg daily, for a mean of 150 weeks. Six patients had normal ALT within 6 months of starting the salvage treatment. At their most recent follow-up visit, two patients had undetectable HBV DNA, two had between 100-1000 copies/mL, and three had between 10,000 and 100,000 copies/ mL, according to the researchers. One patient had lost hepatitis B surface antigen.

In one patient, ALT levels persistently fluctuated and histologic studies continued to show mild viral hepatitis.

No genotypic resistance to adefovir was detected.

"Early treatment with adefovir dipivoxil when HBV DNA is still low is important to increase the chance of maintained virological suppression for lamivudine resistance," the authors write.

"In the future, monoprophylaxis with more potent antiviral agents (e.g., entecavir or tenofovir) without HBIg should be considered for liver transplantation," Dr. Chan said. "It may be associated with good viral control, low risk of resistance, and a lower cost than HBIg-containing regimes."

J Med Virol 2009;81:224-229.