IVI epoprostenol is the only therapy for pulmonary arterial hypertension (PAH) with a randomized controlled trial demonstrating improved survival, when used as first-line monotherapy. In Australia it is used as salvage therapy for those failing treatment with other targeted therapies or presenting in World Health Organization functional class (FC) IV.
Salamonsen, M. R., Keating, D., Whitford, H., Bailey, M., Miller, T., Manterfield, C., & Williams, T. J. (2011). IVI epoprostenol as salvage therapy in pulmonary arterial hypertension: An Australian perspective. Internal Medicine Journal, 41(3), 245 - 251. https://doi.org/10.1111/j.1445-5994.2010.02333.x