Antiretroviral regimens including either Viread (tenofovir) or Epivir (lamivudine or 3TC)  lower the risk of infection with hepatitis B virus (HBV) among HIV-positive gay men who haven't been vaccinated against hep B, aidsmap reports. Publishing their findings in the online edition of Clinical Infectious Diseases, Japanese researchers examined stored blood samples from 1997 to 2009 of 354 un-vaccinated gay men with HIV who were not infected with hep B. They concluded that both Viread and Epivir could prevent hep B infection and that the drugs lowered the risk of incident risk by up to 90 percent.

Most recommended ARV regimens contain Viread, which is a component of Truvada, Atripla and Complera, or Epivir, which is found in Epzicom and Trizivir.

The men in the study were divided into three categories: those taking an ARV regimen containing Viread or Epivir, those taking different ARVs, and those not on therapy. Within the group, 43 people (12 percent) were newly infected with HBV during the follow-up period. Thirty of those infections were among those not taking ARVs; six were in those taking regimens without Viread or Epivir; and seven infections were among those taking Epivir, with a portion of this group also taking Viread.

The rate of hepatitis B infection was 0.669 per 100 person years for those on either Viread or Epivir, compared with a rate of 6.726 for those not on ARVs and 5.265 for men treated with different ARVs.

The investigators stated that their findings lend support to the argument for treating HIV earlier in the course of infection.

To read the aidsmap story, click here.

To read the study abstract, click here.