Method for treating a pulmonary hypertension condition

1. A method for treating pulmonary arterial hypertension (PAH) in a human subject, comprising administering a therapeutically effective amount of ambrisentan to the subject in combination with a therapeutically effective amount of a phosphodiesterase-5 (PDE5) inhibitor selected from sildenafil, tadalafil and vardenafil, wherein an initiation of administration of ambrisentan and the PDE5inhibitor is not greater than about 2 years from first diagnosis of the PAH in the subject.

2. The method of claim 1 , wherein the PAH is of WHO Class II, III or IV.

3. The method of claim 1 , wherein the subject has idiopathic PAH.

4. The method of claim 1 , wherein the subject has non-idiopathic PAH.

5. The method of claim 4 , wherein the non-idiopathic PAH is secondary to scleroderma, systemic lupus erythematosus, anorexigen use or HIV infection.

6. The method of claim 1 , wherein the subject has at least one of

(a) mean PAP of at least about 25 mmHg at rest or at least about 30 mmHg while exercising,

(b) pulmonary vascular resistance (PVR) of at least about 3 mmHg/L/min, and/or

(c) pulmonary capillary wedge pressure (PCWP) or left ventricle end diastolic pressure (LVEDP) not greater than about 15 mmHg.

7. The method of claim 1 , wherein the PDE5 inhibitor comprises tadalafil.

8. The method of claim 1 , wherein the ambrisentan is administered in a daily dosage amount of about 1 mg to about 25 mg.

9. The method of claim 1 , wherein the ambrisentan is administered in a daily dosage amount of about 2.5 mg to about 10 mg.

10. The method of claim 1 , wherein the ambrisentan and the PDE5inhibitor are administered in one dosage form for administration at the same time.

11. The method of claim 1 , wherein the ambrisentan and the PDE5inhibitor are administered separately at different times.