Table 1: Drugs currently available (post-2010) or under clinical trials for PAH.

 

Drug Name

Type of Drug

Stage

Route of Delivery

Working Mechanism

Work on animal Models

Amlodipine

Calcium Channel Blocker

Currently Available

Oral

CCBs prevent Ca2+ entry into cells, Ca2+ will not serve as an intracellular messenger. CCBs will act as a smooth-muscle dilator.

Tested in rats [25].

Epoprostenol

Prostanoid

Currently Available

I.V.

Acts as a selective IP-prostacyclin receptor agonist. This will promote vasodilation and inhibition of vascular smooth muscle cells.

Tested in pigs [6,15].

Treprostinil

Prostanoid

Clinical Trial (phase 3)

I.V. or Inhaled

Acts as a selective IP-prostacyclin receptor agonist. This will promote vasodilation and inhibition of vascular smooth muscle cells.

Tested in male and female rat models [6].

Macitentan

Endothelian Receptor Antagonist

Clinical Trial (phase 2)

Oral

ERAs will either interact with ERA-A or ERB. When the antagonist interacts with either of these receptors, it will either promote vasoconstriction or vasodilation respectively.

Work in rat models [2,19].

Ambrisentan

Endothelian Receptor Antagonist

Currently Available

Oral

ERAs will either interact with ERA-A or ERB. When the antagonist interacts with either of these receptors, it will either promote vasoconstriction or vasodilation respectively.

Work in rat models [16].

Riociguat

Phosphodiesterase-5 (PDE5) Inhibitors

Currently Available

Oral

Prevents hydrolysis of cGMP. cGMP prevents vasoconstriction. Nitric oxide is release as a mediator which will promote vasodilation.

Work in rat models [2,16].

Sildenafil

Soluble Guanylyl Cyclase stimulants

Currently Available

Oral

sGC stimulator will promote NO binding on heme group. Allows for cGMP synthesis, which will interact with the Nitric oxide cycle and promote vasodilation.

Work on mouse models [2,7,11].