ACADIA Announces Results from Phase III Trial of Pimavanserin in Parkinson’s Disease Psychosis
News Sep 02, 2009
ACADIA Pharmaceuticals Inc. has announced top-line results from the first pivotal Phase III trial with pimavanserin in patients with Parkinson’s disease psychosis, or PDP. The study did not meet its primary endpoint of antipsychotic efficacy as measured using the Scale for the Assessment of Positive Symptoms, or SAPS.
Pimavanserin met the key secondary endpoint of motoric tolerability as measured using the Unified Parkinson’s Disease Rating Scale, or UPDRS. Pimavanserin was safe and well tolerated, with the frequency of adverse events generally similar in the pimavanserin and placebo arms.
The primary endpoint of the study was the mean change in SAPS scores at day 42 compared to baseline for each of the two pimavanserin treatment arms versus placebo. Patients showed marked improvements in the SAPS scores across all study arms.
Mean reductions in SAPS scores were 5.9 points in the placebo arm, 5.8 points in the 10 mg pimavanserin arm, and 6.7 points in the 40 mg pimavanserin arm. Statistical significance was not achieved in either pimavanserin arm primarily due to the larger than expected improvement in placebo-treated patients.
“While we obviously are disappointed with the results of this Phase III study, we continue to believe in the potential of pimavanserin based on our clinical experience to date,” said Uli Hacksell, Ph.D., Chief Executive Officer of ACADIA. “We will thoroughly analyze these data along with the data on other secondary and exploratory endpoints over the next month to better understand the outcome of this study. Meanwhile, we are continuing with the second Phase III PDP trial with pimavanserin.”