[Simplification to lamivudine, zidovudine, and abacavir therapy: impact on adherence, clinical outcome, and economic issues]

OBJECTIVES

To analyze the influence on adherence and clinical outcome of the replacement of a previous antiretroviral therapy to a simplified approach using zidovudine, lamivudine, and abacavir (Trizivir) and to assess its economic impact.

METHODS

A retrospective study of 75 pretreated, HIV-infected adult patients who received Trizivir from May 2001 to December 2002. Adherence was assessed by dispensation records or medication counting, CD4 lymphocyte counts, and viral load before and six months after medication change was analyzed; finally, the cost of each therapy was assessed in order to calculate the economic impact of medication change.

RESULTS

Mean adherence significantly increased a 2.5% after medication change; 16 more patients reached optimal adherence, with an NNT (number of patients requiring therapy change in order to obtain one more adherent) of 4.7. The number of patients with undetectable viral load remained almost similar, and mean CD4 cell counts stayed above 500 cells/mm3 in both periods of time. A great variability in incremental costs was seen, due to the varying costs of the previous treatments, and the influence of five intensification therapies using Trizivir. However, when only simplification regimens were analyzed such variability was reduced, and even became favorable in selected cases.

CONCLUSIONS

Changing to a simplification therapy using Trizivir resulted in improved adherence, similar clinical outcomes, and a varying economic impact depending on previous antiretroviral therapy costs.

Costs of medical services for patients with HIV/AIDS in Khon Kaen, Thailand

OBJECTIVE

To estimate the savings and cost of providing highly active antiretroviral therapy (HAART) to adult patients with AIDS under Universal Coverage (UC) in Khon Kaen Province, Thailand.

DESIGN

Micro-costing of outpatient and inpatient services of two referral hospitals, and cost modelling.

SETTING

Khon Kaen Regional Hospital and Northeast Regional Infectious Hospital.

PATIENTS

Adult patients who resided in Khon Kaen and made outpatient visits at and/or those who were discharged from those hospitals from 1 December 2001 to 28 February 2002.

MAIN OUTCOME MEASURE

The average cost per outpatient visit and per inpatient day. Based on these figures, the savings and cost of providing HAART to adult patients with AIDS under UC at outpatient settings in this province were estimated.

RESULTS

The average cost per outpatient visit with and without antiretroviral drugs (ARV) was US$294.2 and US$26.1, respectively. The average cost per inpatient day with and without ARV drugs was US$368.1 and US$43.8, respectively. The net annual cost of HAART was estimated to be US$5 674 629. This is equivalent to 20.0% of the annual UC budget for adults in this province in 2002. Sensitivity analysis and projection to the year 2006 were conducted.

CONCLUSION

A large increase in the budget would be required to provide HAART to all adult patients with AIDS under UC. However, the sensitivity analysis showed it would be an affordable policy option if low-cost antiretroviral drugs were successfully introduced. This type of analysis would be useful to assess the financial implications of providing HAART in public health systems worldwide.