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This is a phase III/IV, double-blinded study to compare two treatment strategies; first line combination therapy (ambrisentan and tadalafil) versus first-line monotherapy (ambrisentan or tadalafil) in subjects with PAH.  This will be assessed to the first clinical failure event.
IRB Protocol Number

All Other Trials

  • Lungs & Respiratory
Eligibility and Other Participant Information

Main Inclusion Criteria:

1) Age 18-75

2) WHO Group 1.1, 1.2, 1.3.1, 1.3.4, 1.3.5, (Idiopathic PAH, Heritable/Familial PAH, Drug- and toxin-induced PAH, PAH associated with collagen vascular disease, HIV infection) 1.3.2 repaired >1 year (PAH associated with congenital systemic-to-pulmonary shunts)

3) Functional class II or III

4) mPAP >/= 25mm Hg, PVR >/= 240 dynes, PCWP or LVEDP </= 15mm Hg

5) TLC >/= 60%, FEV1 >/= 55%

Main Exclusion Criteria:

1) Treatment with a PAH therapy within four weeks of screening (ERA, PDE5, prostanoid)

2) Subjects who previously discontinued an ERA or PDE5 treatment for safety or tolerability reasons


For more information, please contact the Pulmonary Hypertension Center at 720-848-6518.