ITI-214 is a potent, CNS-active, orally bioavailable PDE1 inhibitor (Ki of 58 pM) with excellent selectivity against other PDE family members and against a panel of enzymes, receptors, transporters and ion channels. ITI-214 inhibits recombinant full-length human PDE1A, PDE1B and PDE1C with Kis of 33 pM, 380 pM and 35 pM, respectively. ITI-214 shows efficacy in various animal models of motor and cognitive functions.