Sumatriptan. A pharmacoeconomic review of its use in migraine.

Migraine is a common illness characterised by severe, often throbbing and/or unilateral headache, which may be accompanied by sensitivity to light or noise. A minority of migraine attacks are preceded by transient visual or sensory disturbances. Migraine is associated with reductions in health-related quality of life both during and between attacks. Despite methodological limitations in cost-of-illness studies, it is clear that the cost of migraine to society is substantial. Indirect costs (primarily workplace productivity losses) make up 75 to 90% of total costs. Direct costs, such as the cost of drug treatment, physician consultation, hospitalisation and emergency room treatment, make up most of the remainder. Sumatriptan is an effective and well tolerated agent in the treatment of migraine. Its main advantage over other agents used in the acute management of migraine appears to be its rapid onset of action. Sumatriptan reduces headache severity within 2 hours of oral administration in 50 to 67% of patients and within 1 hour of subcutaneous administration in 70 to 80% of patients. Headache recurs in approximately 40% of patients who initially respond to oral or subcutaneous sumatriptan; however, a second dose of the drug is effective against the symptoms of recurrence in a majority of patients. Some patients experience relief of non-headache migraine symptoms, including nausea, vomiting, photophobia and phonophobia. Adverse events reported after sumatriptan are generally mild and transient. Data from studies of patients who used their usual therapies and sumatriptan in nonblinded, sequential phases indicate that both workplace and nonworkplace productivity losses were reduced during sumatriptan therapy. A cost-benefit analysis applied to some of these workplace productivity data indicated that, including direct costs and productivity savings, sumatriptan was associated with a net reduction in total cost of migraine. In retrospective cost analyses, sumatriptan was associated with increased prescription costs: the effect of the drug on other direct treatment costs was less clear. A retrospective pharmacoeconomic model suggested that the cost-effectiveness of subcutaneous sumatriptan versus subcutaneous dihydroergotamine depended on which outcome measure was of greatest interest. For measures of rapid relief of migraine, sumatriptan was superior, but the cost of achieving rapid relief was substantial. Sumatriptan improved global quality-of-life scores compared with patients' usual therapy in a randomised crossover trial and appeared to do the same when the drugs were administered in nonblinded, sequential phases in trials which used general and migraine-specific quality-of-life instruments. Thus, sumatriptan is associated with a fast onset of action and improvements in health-related quality of life in patients with migraine. However, the cost of achieving rapid relief of migraine symptoms may be substantial. Compared with patients' usual treatments, sumatriptan appeared to reduce workplace and non-workplace productivity losses. However, few economic data from well controlled prospective comparisons of sumatriptan with other available agents are available to quantify the effect of sumatriptan on the overall cost of migraine.