ABSTRACT
Despite the remarkable advances in the development of targeted therapies for pulmonary arterial hypertension (PAH) over the past decade, a substantial number of patients either manifest an incomplete response to monotherapy or fail to respond altogether. This is not particularly surprising, given the likelihood that multiple pathogenic pathways are operative in PAH (1). As in other complex medical conditions in which multiple interfacing pathways play pathogenic roles, such as HIV infection, cancer, and congestive heart failure, a treatment strategy that targets several pathways has appeal in PAH; although only a handful of clinical trials using combination strategies have been completed to date and critical questions remain unanswered, combination therapy is widely used in clinical practice. In this chapter we will review current recommendations, explore the role of combination therapy and discuss future targets for drug development in PAH.
