Tanaproget is a novel nonsteroidal progesterone receptor agonist which can bind to the PR from various species with a higher relative affinity than reference steroidal progestins.
Ralinepag is a potent, orally bioavailable and non-prostanoid prostacyclin (IP) receptor agonist, with EC50s of 8.5 nM, 530 nM and 850 nM for human and rat IP receptor and human DP1 receptor, respectively.