The MTX dose was kept unchanged throughout the study.

No statistical difference in survival over 12 weeks was observed in patients with PAH/SSD treated with FLOLAN as compared with those receiving conventional therapy alone.

One such drug (epoprostenol) is effective only if given intravenously through a small plastic tube that must remain in the vein permanently.

AC-052-355 was a multi-centre, randomised, double-blind, parallel-group study of bosentan versus placebo in 33 patients with severe PAH who were receiving concomitant epoprostenol therapy.

If the clinical situation deteriorates, therapies that are recommended at the severe stage of the disease (eg, epoprostenol) should be considered (see section 4.2).

If the clinical situation deteriorates, therapies that are recommended at the severe stage of the disease (e.g. epoprostenol) should be considered (see section 4.2).

At the end of the treatment period, 4 of 56 (7%) patients receiving FLOLAN died, whereas 5 of 55 (9%) patients receiving conventional therapy alone died.