Pimavanserin – Major Depressive Disorder


Pimavanserin is a proprietary small molecule that we have advanced to Phase 2 development for major depressive disorder (MDD). Pimavanserin is a selective serotonin inverse agonist (SSIA) preferentially targeting 5-HT2A receptors. Its distinct mechanism of action targets serotonergic 5-HT2A receptors that may play a role in depression.

About Major Depressive Disorder

According to the National Institute of Mental Health, MDD affects approximately 16 million adults in the United States and is the leading cause of disability in people age 15 to 44. MDD is a condition characterized by depressive symptoms, such as a depressed mood or a loss of interest or pleasure in daily activities for more than two weeks, as well as impaired social, occupational or other important functioning. The majority of people who suffer from MDD do not respond to initial antidepressant therapy.


We are currently conducting a Phase 2, 10-week, randomized, double-blind, placebo-controlled, multi-center study, referred to as the CLARITY study. CLARITY is designed to examine the efficacy and safety of adjunctive use of pimavanserin in patients with major depressive disorder who have an inadequate response to standard antidepressant therapy with either a selective serotonin reuptake inhibitor (SSRI) or a serotonin norepinephrine reuptake inhibitor (SNRI).