Clinical

Tenofovir an option in HIV/HBV coinfection

Last Updated: 2005-02-25 15:41:12 -0400 (Reuters Health)

By Deborah Mitchell

BOSTON (Reuters Health) - In a head-to-head clinical trial comparing the efficacy of tenofovir with adefovir, researchers found that tenofovir safely and effectively lowers hepatitis B virus levels in patients who are also infected with HIV.

"This is the first randomized, controlled study to show that tenofovir is an option in the treatment of patients co-infected with HIV and HBV," lead investigator Dr. Marion Peters said. "Twenty percent of HIV-infected subjects have hepatitis B," she explained, "so coinfection is a major issue, both in this country and worldwide," she told participants of the 12th Annual Retroviral Conference on Thursday.

Dr. Peters of San Francisco and other investigators in AIDS Clinical Trial Group A5127 enrolled 52 co-infected patients who were on stable combination antiretroviral therapy. At baseline 75% of the subjects had HIV RNA below 50 copies/mL and 98% had compensated liver disease.

The subjects were randomized to tenofovir 300 mg plus placebo or adefovir 10 mg plus placebo daily for up to 96 weeks, and underwent laboratory evaluations weekly. Eighty percent of the subjects were lamivudine-experienced.

Tenofovir has shown "activity against both wild-type and lamivudine-resistant HBV," Dr. Peters explained. Tenofovir is approved for treating HIV infection, but not HBV infection. Adefovir is currently licensed for HBV infection.

"The study was stopped after 52 of 60 subjects had accrued because we met our primary endpoint, showing that tenofovir was not inferior to adefovir and in fact decreased HBV DNA more than adefovir," she said.

At 48 weeks, the mean log10 time-weighted average change in HBV DNA from baseline was -4.4 in the tenofovir group and -3.21 in the adefovir group.

Laboratory abnormalities were seen in 18 patients in both arms, but there were no adverse events. Although there were two deaths in each group, they were not related to the drugs, she said. No renal toxicities were detected.

"In summary, tenofovir is an option for the treatment of co-infected subjects. Although there are uncontrolled data published, this is the first randomized, controlled study showing this effect. So we have now added an option for these patients," she concluded.