Treatment of multiple sclerosis with interferon â: an appraisal of cost-eVectiveness and quality of life

Objective—To evaluate the cost-eVectiveness of interferon beta-1b (IFâ-1b) for relapsing-remitting multiple sclerosis (RRMS). Methods—Construction of a cost-eVectiveness model using published data on IFâ-1b eVectiveness and the natural history of RRMS, and new data on costs and quality of life (QoL) from a sample of 102 patients with RRMS and resident in northern England. Results—Poorer QoL was found for patients with multiple sclerosis compared with the general population; those who had had a relapse; those with worse states identified by a clinical measure (expanded disability status scale (EDSS)). Relapses have eVects over several months. Health state valuations were higher than in the general population. Costs were higher in relapse than remission and for worse EDSS states. IFâ-1b costs were larger than cost savings. The best costeVectiveness estimate was £28 700 per relapse avoided, which is £809 900 per QALY gained; or £328 300 per QALY gained allowing for eVects of progression over 5 years. Estimates were robust to changes in assumptions. Conclusions—The impact of multiple sclerosis on QoL is substantial. Future trials should base outcomes measurement on QoL and be better linked to natural history and cost data. IFâ-1b produces important occasional short term QoL gains, but small gains in QALYs overall and large additional costs. (J Neurol Neurosurg Psychiatry 2000;68:144–149)