Lamivudine Enhances Zidovudine Efficacy

BioChem Pharma and Glaxo have announced results of two Phase II/III trials of the antiviral lamivudine (formerly 3TC) in combination with zidovudine (Wellcome's Retrovir), in the treatment of patients with HIV infection. The results are sufficiently encouraging that Glaxo, which licenses the drug, says it plans to file for approval of the compound as a treatment of HIV infection in the first half of 1995.

The two studies were presented at the 2nd International Conference on Drug Therapy in HIV Infection in Glasgow, Scotland, last week. A total of 352 patients were included in the trials, which were carried out over a 24-week period and included three measures of drug activity, increases in CD4 lymphocyte counts; decrease in levels of virus detectable in blood cells, and decreases in the levels of virus detectable in plasma/serum. Notably, no endpoints were included which looked at clinical outcome.

Christine Katlama from the Hopital Pitie Salpetriere in France presented the results of the first study, which included 129 HIV-positive patients who were given 300mg bid lamivudine plus zidovudine or zidovudine alone. All participants had CD4 counts of 100-400 cells/mm3 at entry. Prof Katlama said that those on combination therapy showed maximum average increases in CD4 counts of 85 cells/mm3, which was sustained at 80 cells/mm3 above baseline at week 24.