Similarities and Differences between the United States and Europe in the Development of Fixed Combination Products for the Treatment of Hypertension

In clinical trials, generally only about half of unselected patients with mild to moderate hypertension respond to treatment with antihypertensive monotherapy. In clinical practice, only about a quarter of hypertensive patients actually achieve the desired target blood pressure levels. Fixed-dose combination antihypertensive therapy is thus important in order both to increase the proportion of patients in whom blood pressure control is achievable and to simplify treatment regimens, thus contributing to improved patient compliance and hence improved blood pressure control in community practice.

Fixed-dose antihypertensive combination products have been available for many years, but even in the early 1980s they were not universally accepted in academia. Recognition of the importance of combination products for the treatment of hypertension has increased during the last two decades in both the United States and Europe. Such recognition is likely to increase further as clinical consensus guidelines establish increasingly ambitious targets for blood pressure control and as global efforts increase to implement such guidelines into general practice.

There are similarities and some differences between the United States and Europe both in clinical guidelines for the treatment of hypertension and in regulatory requirements for the development of fixed-dose antihypertensive combination products. The regulatory requirements of both regions require that the two (or more) components of a combination product must be shown to contribute to its effect. However, available information suggests that compliance with European Union (EU) guidelines requires more extensive clinical evaluation than compliance with United States Food and Drug Administration (FDA) recommendations.