[Budget impact of a set-dose combination of efavirenz-emtricitabine-tenofovir in the treatment of patients infected with HIV-1].

Objective: Estimate the budgetary impact of using a set-dose combination of efavirenz-emtricitabine-tenofovir for the Spanish health care system's treatment of patients infected with HIV-1, while evaluating repercussions for each autonomous community in 2008.

Methods: We developed a budgetary impact model with pharmacological costs for the different currently available treatment options, based on GeSida's recommended guidelines for treating HIV-positive patients. The model defines five possible scenarios in which various possibilities for substituting different drug cocktails with the efavirenz-emtricitabine-enofovir combination are contemplated.

Results: The investment per patient on a national level amounts to euro7,989 in the base scenario (without considering the availability of the efavirenz-emtricitabine-tenofovir combination) and to euro7,997, euro8,424, euro7,830, euro8,375 and euro8,527 for scenario 1 (substitution of recommended drugs with efavirenz, emtricitabine and tenofovir or efavirenz, lamivudine and tenofovir); scenario 2 (substitution of recommended drugs with efavirenz); scenario 3 (substitution of recommended drugs with tenofovir); scenario 4 (substitution of recommended drugs with tenoforvir or zidovudine) and scenario 5 (total substitution), respectively. Compared with the base scenario this means increments of 0.11 %, 5.45 %, -1.99 %, 4.83 % and 6.73 % for scenarios 1, 2, 3, 4 and 5.

Conclusion: Use of a set combination of efavirenz, emtricitabine and tenofovir to treat adult patients with the HIV-1 virus would lead to slight surpluses or even budgetary savings by decreasing the number of daily doses, which could increase patients' quality of life and help them stay on the treatment properly.