Cost-effectiveness analysis of rizatriptan and sumatriptan versus Cafergot® in the acute treatment of migraine

Background: Both ergotamine and selective serotonin 5-HT1B/1D receptor agonists ('triptans') are currently used in the treatment of moderate to severe migraine. Ergotamine is a traditional therapy with a lower drug acquisition cost compared with triptans. It has been shown that triptans are more efficacious than ergotamine, but the higher acquisition costs and shorter duration of action are disadvantages of triptans compared with ergotamine. Objective: The purpose of this study was to provide a comparison of the cost-effectiveness of rizatriptan 10 mg and sumatriptan 50 mg tablets with that of a fixed-dose combination of ergotamine tartrate plus caffeine (Cafergot(R)) in the treatment of an acute migraine attack. The cost-effectiveness of rizatriptan in comparison with sumatriptan was also assessed. Methods: Three separate decision tree models were developed (model 1: rizatriptan vs Cafergot(R); model 2: sumatriptan vs Cafergot(R); model 3: rizatriptan vs sumatriptan). The time horizon was 1 year. Cost-effectiveness analysis was conducted from the societal perspective using cost and effectiveness estimates from the literature. All costs were converted to US dollars (2003). The cost-effectiveness ratio was expressed as incremental cost per quality-adjusted life-year (QALY) gained. Results: Base case evaluation showed that both rizatriptan and sumatriptan dominated Cafergot(R). The net annual saving associated with use of rizatriptan was $US622.98 per patient, with an incremental QALY of 0.001. Use of sumatriptan resulted in a saving of $US620.90 and an increase in QALY. The cost-effective ratios were not sensitive to changes in key variables such as efficacy, utility, drug costs, hospitalisation cost and patient preference over alternative therapies. The study further showed that rizatriptan is more cost effective than sumatriptan, as evidenced by its lower cost and greater effectiveness. Sensitivity analysis showed that the cost-effectiveness ratios were sensitive to moderate changes in drug efficacy. Conclusion: Rizatriptan and sumatriptan were less costly and more effective than Cafergot(R) in the treatment of an acute migraine attack. Rizatriptan was somewhat less costly and more effective than sumatriptan. Additional quality-of-life studies are needed to confirm the benefits of using triptans in the management of migraine.