- Pimavanserin as an adjunctive treatment for patients with MDD showed significant overall improvement in HAMD-17 total score compared to placebo
- Phase 3 CLARITY program initiated in April 2019
SAN DIEGO--(BUSINESS WIRE)-- ACADIA Pharmaceuticals Inc. (Nasdaq: ACAD), announced today that positive results from the Phase 2 CLARITY study evaluating pimavanserin as adjunctive treatment in patients with major depressive disorder (MDD) have been published online by The Journal of Clinical Psychiatry, the official journal of the American Society of Clinical Psychopharmacology (ASCP). In this 10-week, randomized, double-blind, placebo-controlled study (n=207), pimavanserin met the overall primary endpoint of the study by significantly reducing the 17-item Hamilton Depression Rating Scale (HAMD-17) total score compared to placebo (p=0.039). In the parallel design portion (Stage 1) of this two-stage sequential parallel comparison design (SPCD) study, adding pimavanserin to first-line SSRI or SNRI therapy also significantly reduced HAMD-17 scores compared to placebo (p=0.0003). On the key secondary endpoint, pimavanserin also demonstrated statistically significant reductions compared to placebo in the Sheehan Disability Scale (SDS) score (p=0.004).
The study published today, “A Phase 2, Randomized, Double-Blind, Placebo-Controlled Study of Adjunctive Pimavanserin in Patients with Major Depressive Disorder and an Inadequate Response to Therapy (CLARITY),” also included positive overall results observed for additional secondary study endpoints with nominal p-values including: Clinical Global Impression-Severity (p=0.0084), Clinical Global Impression-Improvement (p=0.0289), Karolinska Sleepiness Scale (p=0.0205), Massachusetts General Hospital Sexual Functioning Index (p=0.0003), and Barratt Impulsiveness Scale (p=0.0075). Pimavanserin was well-tolerated in the study and the most common adverse events reported in the pimavanserin group were dry mouth, nausea, and headache all with frequency of less than 10%.
“Today, the standard of care in MDD is to start patients on SSRI or SNRI therapies. However, a majority of patients do not adequately respond to these initial treatments and are prescribed an adjunctive therapy to manage their symptoms,” said Professor Maurizio Fava, M.D., Executive Vice Chair, Department of Psychiatry, Massachusetts General Hospital (MGH) and Associate Dean for Clinical & Translational Research, Harvard Medical School. “Results from this study suggest pimavanserin could be an important new adjunctive treatment for MDD patients who continue to experience significant depression with their initial therapy.”
“Based on these positive Phase 2 results, we initiated our Phase 3 CLARITY program earlier this year to further evaluate pimavanserin as an adjunctive treatment option for MDD. At least one additional positive trial out of the two ongoing Phase 3 studies, together with our Phase 2 study, will serve as the basis for an sNDA submission,” said Serge Stankovic, M.D., M.S.P.H., ACADIA's President.
About the Phase 2 CLARITY Study
The study was conducted in collaboration with the MGH Clinical Trials Network & Institute (CTNI) and randomized 207 adult patients with a confirmed inadequate response to existing first-line selective serotonin reuptake inhibitor (SSRI) or serotonin norepinephrine reuptake inhibitor (SNRI) therapy for MDD across 27 U.S. clinical research centers.
Consistent with the SPCD design, the study was conducted in two, five-week sequential stages. Eligible subjects continued receiving their SSRI or SNRI antidepressant at a stable dose for the duration of the study. Patients were randomly assigned (1:3) to pimavanserin 34 mg/day or placebo in Stage 1. Placebo non-responders in Stage 1 (defined as HAMD-17 total score >14 and a percent-reduction from baseline in HAMD-17 total score of