An evaluation of the cost effectiveness of adding lamivudine to zidovudine-containing regimens in HIV infection. Canadian perspective.

backgroundA prospective cost-effectiveness analysis undertaken as part of the CAESAR (Canada, Australia, Europe, South Africa) placebo-controlled clinical trial showed that the addition of lamivudine to zidovudine-containing regimens for 1 year reduced progression of HIV infection to AIDS or death, as well as significantly reducing the number of hospitalisations, outpatient visits and the requirement for medications for HIV-related illness and adverse events. Data from all 1840 patients included in the 'intent-to-treat' population of the CAESAR trial were used for the present analysis. A Canadian third-party payer perspective was adopted, and all costs were adjusted to 1997 prices.

resultsThe savings associated with reduced healthcare resource use in the CAESAR study were estimated to be 1123 Canadian dollars ($Can) per patient, over the year. These savings partly offset the cost of lamivudine. The analysis showed that the addition of lamivudine to zidovudine-containing regimens resulted in an incremental cost-effectiveness ratio of $Can 14,225 [95% confidence interval (CI): $Can4383 to $Can29,577] for progression to AIDS/death avoided and of $Can5631 (95%CI: $Can2010 to $Can12,929) for HIV-related illness avoided.

conclusionsOur findings indicate that treatments that slow the progression of HIV infection to AIDS or death have the potential to facilitate healthcare savings, which partly offset the drug acquisition costs. The results also demonstrate that it is possible to undertake economic evaluations in parallel with a major clinical end-point study.