Cost and cost-effectiveness of switching from d4T or AZT to a TDF-based first-line regimen in a resource-limited setting in rural Lesotho

Abstract

Background: Latest World Health Organization guidelines recommend shifting away from Stavudine (d4T)-based regimens due to severe side effects. However, widespread replacement of d4T by Tenofovir (TDF) or Zidovudine (AZT) is hampered by cost concerns.

Methods: We established the cost-effectiveness of alternative first-line regimens using primary utilization, cost, and outcome data from a program in a rural district in Lesotho. We calculated cost per patient-year, incremental costs, and incremental cost-effectiveness ratios per life year, and per Quality Adjusted Life Year gained. Uncertainty was assessed using multiway and probabilistic sensitivity analyses.

Results: Our study included 1260 patients representing 1635 patient-years on antiretroviral therapy (ART). Six hundred eight patients were on TDF, 290 were on AZT, and 362 were on d4T. Patients on d4T experienced more toxicities; toxicities with the biggest impact on quality of life were moderate neuropathy and severe lipodystrophy. The cost per patient-year ranged from US $266 on d4T to US $353 on TDF. Inpatient care and essential drug costs were higher for patients on d4T than on AZT or TDF. Incremental cost-effectiveness ratio results suggest that AZT-based ART is weakly dominated by a combination of d4T- and TDF-based ART.

Discussion: This is one of the first analyses to investigate the cost-effectiveness of TDF using primary data in a resource-poor setting. Although TDF-based first-line ART is more costly than d4T, it is also more effective. Political pressure should be exerted to encourage further price reductions and additional generic manufacturing for TDF and partner drugs such as Efavirenz. This should be met by a commitment from donors and implementers to ensure that supply is met by a clear demand.