A Local, Multi-centre, Open Label Access Study, To Provide Sildenafil Therapy To Eligible Adult Patients With Pulmonary Arterial Hypertension Completing A1481244 Study In India Or Ongoing In A1481269 Study Who Continue To Receive Benefit From Sildenafil Therapy.

In an earlier study, sildenafil citrate administered to patients of PAH led to improvement in pulmonary arterial pressure, cardiac output, quality of life, and other parameters as compared to placebo. This protocol provides mechanism for patients who have clinical deterioration on other PAH approved therapies to have access to sildenafil prior to marketing authorization in India.