Cost effectiveness of cilostazol compared with naftidrofuryl and pentoxifylline in the treatment of intermittent claudication in the UK.

Objective: To estimate the cost effectiveness of cilostazol (Pletal) compared to naftidrofuryl and pentoxifylline (Trental) in the treatment of intermittent claudication in the UK.

Design And Setting: This was a modelling study on the management of patients with intermittent claudication who are 40 years of age or above and have at least six months history of symptomatic intermittent claudication, secondary to lower extremity arterial occlusive disease. The study was performed from the perspective of the UK's National Health Service (NHS).

Methods: Clinical outcomes attributable to managing intermittent claudication were obtained from the published literature and resource utilisation estimates were derived from a panel of vascular surgeons. Using decision analytical techniques, a decision model was constructed depicting the management of intermittent claudication with cilostazol, naftidrofuryl and pentoxifylline over 24 weeks in the UK. The model was used to estimate the cost effectiveness (at 2002/2003 prices) of cilostazol relative to the other treatments.

Main Outcome Measures And Results: Starting treatment with cilostazol instead of naftidrofuryl is expected to increase the percentage improvement in maximal walking distance by 32% (from 57% to 75%) for a 12% increase in NHS costs (from 801 pounds sterling to 895 pounds sterling). Treatment with cilostazol instead of pentoxifylline is expected to increase the percentage improvement in maximal walking distance by 67% (from 45% to 75%) and reduce NHS costs by 2% (from 917 pounds sterling to 895 pounds sterling). Treatment with naftidrofuryl instead of pentoxifylline is expected to increase the percentage improvement in maximal walking distance by 27% (from 45% to 57%) and decrease NHS costs by 14% (from 917 pounds sterling to 801 pounds sterling).

Conclusion: Within the limitations of our model, starting treatment with cilostazol is expected to be a clinically more effective strategy for improving maximal walking distance at 24 weeks than starting treatment with naftidrofuryl or pentoxifylline and potentially the most cost effective strategy. Moreover, the acquisition cost of a drug should not be used as an indication of the cost effectiveness of a given method of care.