Phosphodiesterase type 5 inhibitor plus endothelin receptor antagonist compared to either alone for group 1 pulmonary arterial hypertension

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To assess the benefits and harms of combination therapy involving a PDE5 inhibitor and an ERA in adults and adolescents with group 1 PAH (as defined by WHO) compared to either agent alone.

This is a protocol.