7 In a placebo-controlled study of Revatio as an adjunct to intravenous epoprostenol in pulmonary arterial hypertension, a total of 134 patients were treated with Revatio (in a fixed titration starting from 20 mg, to 40 mg and then 80 mg, three times a day) and epoprostenol, and 131 patients were treated with placebo and epoprostenol.