Combination Drugs: Innovation in Pharmacotherapy

A lthough most pharmaceutical innovation is incremental, small improvements in therapy often add up to substantial progress over time.1 Incremental innovation in drug therapy can take various forms, including new agents, new indications for existing drugs, and new dosage forms with improved pharmacologic profiles.1 Combination therapy with two or more agents having complementary mechanisms of action represents a type of incremental innovation that has extended the range of therapeutic options in the treatment of almost every human disease. Combination products—also known as fixed-dose combinations—are combinations of two or more active drugs produced in a single tablet (see Table 1). They provide the advantages of combination therapy while reducing the number of prescriptions and the attendant administrative costs. Unfortunately, the real contribution of combination products to therapeutics has been blurred by perceptions of inherent disadvantages and, as a result, these products are often perceived only as second-line therapy. In this article, we describe the advantages of combination products and discuss the evidence in support of their role in pharmacotherapy.