ACADIA Announces Presentation of Data from Its Pivotal Phase III Parkinson’s Disease Psychosis Study with Pimavanserin at the American Academy of Neurology Annual Meeting
Pimavanserin met the primary endpoint in the -020 Study by demonstrating highly significant antipsychotic efficacy on the 9-item SAPS-PD scale (p=0.001). Pimavanserin also met the key secondary endpoint for motoric tolerability as measured using Parts II and III of the Unified Parkinson’s Disease Rating Scale, or UPDRS. Dr. Cummings presented new data from the -020 Study showing highly significant improvements in all secondary efficacy measures, including the Clinical Global Impression Severity, or CGI-S, scale (p<0.001), the Clinical Global Impression Improvement, or CGI-I, scale (p=0.001), and a CGI-I responder analyses (p=0.002). The CGI-I responder results showed that approximately twice as many subjects in the pimavanserin treatment arm, as compared to placebo, were rated as very much improved or much improved at the conclusion of the study. In addition, pimavanserin demonstrated significant improvements using the full 20-item SAPS scale and each of the separate hallucinations and delusions domains in supportive analyses. Statistically significant benefits were also observed in exploratory measures of nighttime sleep, daytime wakefulness, and caregiver burden.
“The significant and consistent results observed across measures in the
Phase III -020 Study are impressive and potentially very encouraging for
Parkinson’s patients who suffer from the psychosis frequently associated
with this disease,” said Dr.
Safety and Tolerability Profile
Consistent with previous studies, pimavanserin was safe and well tolerated in the -020 Study. The most common adverse events were urinary tract infection (11.7% PBO vs. 13.5% PIM) and falls (8.5% PBO vs. 10.6% PIM). Adverse events were generally characterized as mild to moderate in nature. The only serious adverse events that occurred in more than one patient were urinary tract infection (1-PBO vs. 3-PIM) and psychotic disorder (0-PBO vs. 2-PIM). Over ninety percent of the patients who completed the clinical phase of this trial elected to roll over into the ongoing open-label safety extension study. Patients were only eligible to participate in the extension study if the treating investigator also deemed them to be likely to benefit from continued treatment with pimavanserin.
About the Trial Design
The pivotal Phase III trial, referred to as the -020 Study, was a multi-center, double-blind, placebo-controlled study designed to evaluate the efficacy, tolerability and safety of pimavanserin as a treatment for patients with Parkinson’s disease psychosis. A total of 199 patients were enrolled in the study and randomized on a one-to-one basis to receive either 40 mg of pimavanserin or placebo once-daily for six weeks, following a two-week screening period including brief psycho-social therapy. Patients also received stable doses of their existing anti-Parkinson’s therapy throughout the study. The primary endpoint of the -020 Study was antipsychotic efficacy as measured using the “SAPS–PD” scale, which consists of nine items from the hallucinations and delusions domains of the Scale for the Assessment of Positive Symptoms, or SAPS. These nine items have been shown to be particularly relevant to the expression of psychotic symptoms in patients with Parkinson’s disease and to have high inter-rater reliability for assessment of severity. Motoric tolerability was a key secondary endpoint in the study and was measured using Parts II and III of the Unified Parkinson’s Disease Rating Scale, or UPDRS.
Pimavanserin is ACADIA’s proprietary small molecule that acts selectively as an antagonist/inverse agonist on serotonin 5-HT2A receptors and is in Phase III development as a potential first-in-class treatment for Parkinson’s disease psychosis. Pimavanserin can be taken orally as a tablet once-a-day. ACADIA discovered pimavanserin and holds worldwide rights to this new chemical entity.
About Parkinson’s Disease Psychosis
According to the National Parkinson’s Foundation, about one million
ACADIA is a biopharmaceutical company focused on innovative treatments
that address unmet medical needs in neurological and related central
nervous system disorders. ACADIA has a pipeline of product candidates
led by pimavanserin, which is in Phase III development as a potential
first-in-class treatment for Parkinson's disease psychosis. ACADIA also
has clinical-stage programs for chronic pain and glaucoma in
Statements in this press release that are not strictly historical in
nature are forward-looking statements. These statements include but are
not limited to statements related to the progress and timing of ACADIA’s
drug discovery and development programs, either alone or with a partner,
including clinical trials, the benefits to be derived from ACADIA’s
product candidates, in each case including pimavanserin, the potential
benefit of pimavanserin to PDP sufferers, and the potential of a
selective, non-dopaminergic-based therapy to transform the standard of
care for PDP patients by providing an effective, safe and well-tolerated
treatment. These statements are only predictions based on current
information and expectations and involve a number of risks and
uncertainties. Actual events or results may differ materially from those
projected in any of such statements due to various factors, including
the risks and uncertainties inherent in drug discovery, development and
commercialization, and collaborations with others, and the fact that
past results of clinical trials may not be indicative of future trial
results. For a discussion of these and other factors, please refer to
ACADIA’s annual report on Form 10-K for the year ended December 31, 2012
as well as ACADIA’s subsequent filings with the
ACADIA Pharmaceuticals Inc.
Uli Hacksell, Ph.D., Chief Executive Officer