Table 1.

Reported Change in 6-Minute-Walk Distance in Patients Randomized to Active Therapy in the Pulmonary Arterial Hypertension Registration Trials

Drug	Change in 6-Minute-Walk Distance (m)
Epoprostenol (i.v.)	31
Bosentan	36
Ambrisentan	45
Macitentan	12
Sildenafil	45
Tadalafil	33
Riociguat	30
Iloprost (inhaled)	18
Treprostinil (s.c.)	10
Treprostinil (i.v.)	Not measured
Treprostinil (inhaled)	14
Treprostinil (oral)	13
Selexipag	4

Definition of abbreviations: i.v. = intravenous; s.c. = subcutaneous.

Comparisons between drugs should not be made from these results, as the trials varied with respect to the severity of the pulmonary arterial hypertension and the use of background therapies. The minimal improvement for a patient to acknowledge a real benefit has been reported to between 54 and 80 m (47). Exercise training in patients who are stable on optimal therapy can increase their 6-minute-walk distance by 96 m (48).