ACADIA Pharmaceuticals Announces Publication in The Lancet of Pivotal Phase III Parkinson’s Disease Psychosis Trial with Pimavanserin

SAN DIEGO—(BUSINESS WIRE)—Oct. 31, 2013—ACADIA Pharmaceuticals Inc. (NASDAQ: ACAD), a biopharmaceutical companyfocused on innovative treatments that address unmet medical needs inneurological and related central nervous system disorders, todayannounced the publication of data from its pivotal Phase III -020 Studywith pimavanserin in patients with Parkinson’s disease psychosis (PDP)in the November 1, 2013 online issue of The Lancet. In the -020Study, pimavanserin demonstrated significant and clinically meaningfulbenefits and was safe and well tolerated in patients with PDP.Pimavanserin significantly reduced psychosis and maintained motorcontrol in patients with PDP. Significant benefits were also observed inexploratory measures of nighttime sleep, daytime wakefulness andcaregiver burden.

“Among Parkinson’s patients, psychosis causes great distress forpatients and caregivers and is the leading cause ofinstitutionalization,” said Jeffrey Cummings, M.D., Sc.D., Director ofCleveland Clinic Lou Ruvo Center for Brain Health, and lead author.“These data indicate that pimavanserin, a selective 5-HT_2A inverseagonist, confers a meaningful clinical benefit in patients with PDP andhas the potential to be an important new treatment option for thiscondition for which there is no approved therapy in the U.S.”

Pimavanserin met the primary endpoint in the -020 Study by demonstratinghighly significant improvement in psychosis compared to placebo on the9-item SAPS-PD scale (p=0.001), which was assessed by central,independent raters. The mean change in SAPS-PD score represented a 37%improvement for pimavanserin versus 14% for placebo (p<0.001).Pimavanserin also demonstrated significant improvement on the full20-item SAPS (hallucinations plus delusions) measure (p=0.001) and oneach of the separate hallucinations and delusions domains in supportiveanalyses.

Significant improvements were observed for pimavanserin over placebo onadditional investigator-assessed secondary measures of psychosisbenefit, including the Clinical Global Impression Severity, or CGI-S,scale (p<0.001), and the Clinical Global Impression Improvement, orCGI-I, scale (p=0.001). The proportion of CGI-I responders was alsohigher for pimavanserin versus placebo, (49% vs. 26%, p=0.002).Pimavanserin met the key secondary endpoint for motoric tolerability asmeasured using Parts II and III of the Unified Parkinson’s DiseaseRating Scale, or UPDRS. Caregivers in the pimavanserin group alsoreported significant reduction in caregiver burden (p=0.002), andparticipants reported significant improvements on nighttime sleep(p=0.045) and daytime wakefulness (p=0.012) for pimavanserin overplacebo in exploratory analyses.

Consistent with previous studies, pimavanserin was well tolerated in the-020 Study with no significant safety concerns or impairment in motorfunction. The most common treatment-emergent adverse events were urinarytract infection (13.5% PIM vs. 11.7% PBO) and falls (10.6% PIM vs. 8.5%PBO). Although adverse event discontinuations were higher in thepimavanserin group compared to placebo, overall drop-outs in the -020Study were low compared to other reported studies in PDP and similarneuropsychiatric conditions.

“The -020 Study results presented in The Lancet suggest thatpimavanserin has the potential to provide a safe, well-tolerated, andeffective alternative to existing antipsychotic drugs. Current atypicalantipsychotics are often used off-label to treat PDP despite increasingevidence that they are associated with serious safety issues and arepoorly tolerated in this fragile and elderly patient population,” saidClive Ballard, M.D., Professor of Age Related Diseases at King’s CollegeLondon.

Phase III -020 Study Design

The pivotal Phase III trial, referred to as the -020 Study, was amulti-center, double-blind, placebo-controlled study designed toevaluate the efficacy, tolerability and safety of pimavanserin as atreatment for patients with Parkinson’s disease psychosis. A total of199 patients were enrolled in the study and randomized on a one-to-onebasis to receive either 40 mg of pimavanserin or placebo once-daily forsix weeks, following a two-week screening period including briefpsycho-social therapy. Patients also received stable doses of theirexisting anti-Parkinson’s therapy throughout the study. The primaryendpoint of the -020 Study was antipsychotic efficacy as measured usingthe “SAPS–PD” scale, which consists of nine items from thehallucinations and delusions domains of the Scale for the Assessment ofPositive Symptoms (SAPS). Additional secondary and supportive measuresof efficacy were measured using the Clinical Global Impression Severity(CGI-S) scale, the Clinical Global Impression Improvement (CGI-I) scale,and the full 20-item SAPS. Exploratory measures of nighttime sleep,daytime wakefulness, and caregiver burden were measured using the Scalesfor Outcome in Parkinson’s Disease - Nighttime Sleep (SCOPA-NS), theScales for Outcome in Parkinson’s Disease - Daytime Sleep (SCOPA-DS),and the Caregiver Burden Scale (CBS), respectively. Motoric tolerabilitywas a key secondary endpoint in the study and was measured using PartsII and III of the Unified Parkinson’s Disease Rating Scale (UPDRS).

About Pimavanserin

Pimavanserin is ACADIA’s proprietary small molecule that actsselectively as an antagonist/inverse agonist on serotonin 5-HT_2A receptors.ACADIA has successfully completed a pivotal Phase III trial withpimavanserin for Parkinson’s disease psychosis (PDP), potentiallypositioning it to be the first drug approved in the United States forthe treatment of this disorder. Pimavanserin is also in Phase IIdevelopment for Alzheimer’s disease psychosis (ADP) and has completed aPhase II trial as a co-therapy in schizophrenia. Pimavanserin isformulated as a tablet and is administered orally once-a-day. ACADIAdiscovered pimavanserin and holds worldwide rights to this new chemicalentity.

About Parkinson’s Disease Psychosis

According to the National Parkinson’s Foundation, about one millionpeople in the United States and from four to six million peopleworldwide suffer from Parkinson’s disease. Parkinson’s diseasepsychosis, or PDP, is a debilitating disorder that develops in up to 60percent of patients with Parkinson’s disease. Currently, there is noFDA-approved therapy to treat PDP in the United States. PDP, commonlyconsisting of visual hallucinations and delusions, substantiallycontributes to the burden of Parkinson’s disease and deeply affects thequality of life of patients. PDP is associated with increased caregiverstress and burden, nursing home placement, and increased morbidity andmortality. There is a large unmet medical need for new therapies thatwill effectively treat PDP without compromising motor control inpatients with Parkinson’s disease.

About ACADIA Pharmaceuticals

ACADIA is a biopharmaceutical company focused on innovative treatmentsthat address unmet medical needs in neurological and related centralnervous system disorders. ACADIA has a pipeline of product candidatesled by pimavanserin, which is in Phase III development as a potentialfirst-in-class treatment for Parkinson's disease psychosis. ACADIA alsohas clinical-stage programs for chronic pain and glaucoma incollaboration with Allergan, Inc. and two advanced preclinical programsdirected at Parkinson’s disease and other neurological disorders. Allproduct candidates are small molecules that emanate from discoveriesmade at ACADIA. ACADIA maintains a website at www.acadia-pharm.comto which ACADIA regularly posts copies of its press releases as well asadditional information and through which interested parties cansubscribe to receive email alerts.

Forward-Looking Statements

Statements in this press release that are not strictly historical innature are forward-looking statements. These statements include but arenot limited to statements related to the progress and timing of ACADIA’sdrug discovery and development programs, either alone or with a partner,including clinical trials, the benefits to be derived from ACADIA’sproduct candidates, in each case including pimavanserin, the potentialfor pimavanserin to be approved for PDP or be an important new treatmentoption for PDP sufferers, and the potential of pimavanserin to provide asafe, well-tolerated, and effective alternative to existingantipsychotic drugs. These statements are only predictions based oncurrent information and expectations and involve a number of risks anduncertainties. Actual events or results may differ materially from thoseprojected in any of such statements due to various factors, includingthe risks and uncertainties inherent in drug discovery, development andcommercialization, and collaborations with others, and the fact thatpast results of clinical trials may not be indicative of future trialresults. For a discussion of these and other factors, please refer toACADIA’s annual report on Form 10-K for the year ended December 31, 2012as well as ACADIA’s subsequent filings with the Securities and ExchangeCommission. You are cautioned not to place undue reliance on theseforward-looking statements, which speak only as of the date hereof. Thiscaution is made under the safe harbor provisions of the PrivateSecurities Litigation Reform Act of 1995. All forward-looking statementsare qualified in their entirety by this cautionary statement and ACADIAundertakes no obligation to revise or update this press release toreflect events or circumstances after the date hereof, except asrequired by law.

Source: ACADIA Pharmaceuticals Inc.

ACADIA Pharmaceuticals Inc.
Uli Hacksell, Ph.D., Chief ExecutiveOfficer
Lisa Barthelemy, Director, Investor Relations
(858)558-2871