Assessment of costs and benefits of drug therapy for treatment-resistant schizophrenia in the United Kingdom.

An analysis was conducted on the basis of available data to assess the economic consequences of clozapine therapy for people with moderate to severe schizophrenia in long-stay institutions or staffed group homes, with a view to providing an estimate of the likely costs and benefits of the drug. Data from a cost-effectiveness study conducted in the US, supplemented by other literature sources, were used to construct a clinical decision tree for likely clinical outcomes for such patients. A panel of UK psychiatrists provided consensus on how these patients would have been managed in the UK. The costs associated with each patient outcome were estimated, and a sensitivity analysis performed to test the assumptions made. For the patients themselves, clozapine would lead to a net gain of 5.87 years of life with no disability or only mild disability. The base case analysis showed that the direct costs of using clozapine were 91 pounds less per annum (or 1333 pounds per lifetime) than for standard neuroleptic therapy, when the effect on all health-care resources was taken into account. In addition, the sensitivity analysis showed that clozapine would be cost-saving or cost-neutral under many different assumptions. A prospective health economic study with clozapine in the management of schizophrenia would be desirable to confirm these results.