ACADIA Pharmaceuticals Initiates Phase II Study of Pimavanserin in Alzheimer’s Disease Agitation

SAN DIEGO—(BUSINESS WIRE)—Oct. 31, 2016—ACADIA Pharmaceuticals Inc. (NASDAQ: ACAD), a biopharmaceutical companyfocused on innovative treatments that address unmet medical needs incentral nervous system disorders, today announced the initiation ofSERENE, a Phase II study with pimavanserin for the treatment ofagitation in patients with Alzheimer’s disease (AD Agitation). There iscurrently no drug approved by the FDA for the treatment of AD Agitation.Pimavanserin is a selective serotonin inverse agonist (SSIA)preferentially targeting 5-HT_2A receptors, with a distinctmechanism of action compared to other currently available medicines usedoff-label to treat AD Agitation.

“AD Agitation is a common condition and a major cause of distress forAlzheimer’s patients, their families and caregivers,” said SergeStankovic, M.D., M.S.P.H., ACADIA’s Executive Vice President, Head ofResearch and Development. “It also is associated with more rapid declineand earlier institutionalization of patients with AD Agitation. With noFDA-approved therapy for AD Agitation, there is a large, unmet need fora new treatment option for patients.”

About the SERENE Study

SERENE is a Phase II, randomized, double-blind, placebo-controlled,multi-center outpatient study designed to examine the efficacy andsafety of pimavanserin in approximately 430 patients with Alzheimer’sdisease who have agitation and/or aggression symptoms. Patients will berandomized to receive once daily oral doses of 34 mg pimavanserin, 20 mgpimavanserin or placebo for 12 weeks. The primary endpoint in the studyis a reduction in total score on the Cohen-Mansfield Agitation Inventory(CMAI). Following participation in SERENE, patients will be eligible toenroll in an open-label safety extension study.

About Alzheimer’s Disease Agitation (AD Agitation)

According to the Alzheimer’s Association, around 5.4 million people inthe United States are living with Alzheimer’s disease and approximatelyhalf are diagnosed with the disease. Studies suggest that 40 to 50percent of patients diagnosed with Alzheimer’s disease in the UnitedStates exhibit agitation. AD Agitation is characterized by verbalaggression, physical aggression, and excessive motor activities. Thesebehavioral symptoms have been associated with more rapid cognitivedecline, greater caregiver burden, and earlier institutionalization.

About Pimavanserin

Pimavanserin is a selective serotonin inverse agonist (SSIA)preferentially targeting 5-HT_2A receptors. These receptorsare thought to play an important role in AD Agitation. Pimavanserin isbeing evaluated in an extensive clinical development program by ACADIAacross multiple indications. Pimavanserin (34 mg) was approved for thetreatment of hallucinations and delusions associated with Parkinson’sdisease psychosis by the U.S. Food and Drug Administration in April 2016under the trade name NUPLAZID™. NUPLAZID is not approved for thetreatment of AD Agitation.

About ACADIA Pharmaceuticals

ACADIA is a biopharmaceutical company focused on the development andcommercialization of innovative medicines to address unmet medical needsin central nervous system disorders. ACADIA maintains a website at www.acadia-pharm.comto which we regularly post copies of our press releases as well asadditional information and through which interested parties cansubscribe to receive e-mail 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, the expected design and scopeof ACADIA’s clinical trials, and the benefits to be derived fromNUPLAZID™ (pimavanserin) and ACADIA’s product candidates, including thepotential effectiveness of pimavanserin in AD Agitation patients. Thesestatements are only predictions based on current information andexpectations and involve a number of risks and uncertainties. Actualevents or results may differ materially from those projected in any ofsuch statements due to various factors, including the risks anduncertainties inherent in drug discovery, development, approval andcommercialization, and in 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, 2015as 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.

Important Safety Information and Indication forNUPLAZID (pimavanserin) tablets

WARNING: INCREASED MORTALITY IN ELDERLY PATIENTS WITHDEMENTIA-RELATED PSYCHOSIS
Elderly patients withdementia-related psychosis treated with antipsychotic drugs are at anincreased risk of death. NUPLAZID is not approved for the treatment ofpatients with dementia-related psychosis unrelated to the hallucinationsand delusions associated with Parkinson’s disease psychosis.

NUPLAZID is an atypical antipsychotic indicated for the treatment ofhallucinations and delusions associated with Parkinson’s diseasepsychosis.

QT Interval Prolongation: NUPLAZID prolongs the QT interval. The use ofNUPLAZID should be avoided in patients with known QT prolongation or incombination with other drugs known to prolong QT interval includingClass 1A antiarrhythmics or Class 3 antiarrhythmics, certainantipsychotic medications, and certain antibiotics. NUPLAZID should alsobe avoided in patients with a history of cardiac arrhythmias, as well asother circumstances that may increase the risk of the occurrence oftorsade de pointes and/or sudden death, including symptomaticbradycardia, hypokalemia or hypomagnesemia, and presence of congenitalprolongation of the QT interval.

Adverse Reactions: The most common adverse reactions (≥2%for NUPLAZID and greater than placebo) were peripheral edema (7%vs 2%), nausea (7% vs 4%), confusional state (6% vs 3%), hallucination(5% vs 3%), constipation (4% vs 3%), and gait disturbance (2% vs <1%).

Drug Interactions: Strong CYP3A4 inhibitors (eg, ketoconazole)increase NUPLAZID concentrations. Reduce the NUPLAZID dose by one-half.Strong CYP3A4 inducers may reduce NUPLAZID exposure, monitor for reducedefficacy. Increase in NUPLAZID dosage may be needed.

Renal Impairment: No dosage adjustment for NUPLAZID is needed inpatients with mild to moderate renal impairment. Use of NUPLAZID is notrecommended in patients with severe renal impairment.

Hepatic Impairment: Use of NUPLAZID is not recommended in patients withhepatic impairment. NUPLAZID has not been evaluated in this patientpopulation.

Pregnancy: Use of NUPLAZID in pregnant women has not been evaluated andshould therefore be used in pregnancy only if the potential benefitjustifies the potential risk to the mother and fetus.

Pediatric Use: Safety and efficacy have not been established inpediatric patients.

Dosage and Administration: Recommended dose: 34 mg per day, taken orallyas two 17-mg tablets once daily, without titration.

For additional Important Safety Information, including boxed warning,please see the full Prescribing Information for NUPLAZID at https://www.nuplazid.com/pdf/NUPLAZID_Prescribing_Information.pdf.

Source: ACADIA Pharmaceuticals Inc.

Investor Contact:
ACADIA Pharmaceuticals Inc.
LisaBarthelemy
(858) 558-2871
ir@acadia-pharm.com
or
MediaContact:
Taft Communications
Ted Deutsch
(609)578-8765
ted@taftcommunications.com