Cost-effectiveness of an atypical conventional antipsychotic in South Africa: An economic evaluation of quetiapine versus haloperidol in the treatment of patients partially responsive to previous antipsychotics
Background. The introduction of a new generation of atypical antipsychotic agents has raised difficult economic and ethical questions, particularly in lower-income countries. The reported tolerability and efficacy advantages of the atypical antipsychotics over their conventional predecessors have to be weighed against their higher acquisition costs. Pharmaco-economic studies conducted in Western countries consistently report cost advantages or cost neutrality for these new agents. However, considerable differences in health care service provision make it difficult to generalise these findings to South Africa. Method. We compared the direct costs (private and public sector) of treating schizophrenia with an atypical antipsychotic quetiapine, and with a conventional antipsychotic haloperidol, by adapting a decision-analytic pharmaco-economic model for South African circumstances. The sample comprised patients partially responsive to antipsychotics, who had participated in a multinational randomised controlled trial comparing the efficacy and safety of quetiapine versus haloperidol. Results. The estimated total direct cost for the treatment with quetiapine in South Africa was slightly less than for haloperidol for various models in both the private and the public sectors. Conclusions. Significant differences in health care provision make pharmaco-economic studies conducted in other countries invalid for South African circumstances. Previously quetiapine treatment did not result in direct cost savings in South Africa. However, the recently introduced legislation to establish single exit prices for medications has resulted in the cost of quetiapine treatment declining by 36.7% and that of haloperidol by 13%. This has translated into an overall direct cost saving for quetiapine in both the private and public sector models. This, together with additional indirect advantages of the atypical antipsychotics such as improved quality of life and better social and vocational functioning, argues strongly from both an economic and ethical perspective for the use of atypical antipsychotics in treating schizophrenia in South Africa.