ACADIA Pharmaceuticals Initiates Phase II Trial of Pimavanserin for Adjunctive Treatment in Patients With Negative Symptoms of Schizophrenia

SAN DIEGO—(BUSINESS WIRE)—Nov. 15, 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 ofADVANCE, a Phase II study to evaluate pimavanserin for adjunctivetreatment in patients with negative symptoms of schizophrenia. Studiesshow that about 40 to 50 percent of schizophrenia patients suffer fromprominent negative symptoms. There is currently no drug approved by theU.S. Food and Drug Administration for the treatment of these negativesymptoms. As a selective serotonin inverse agonist (SSIA), pimavanserinis a new class of antipsychotic medication with a distinct mechanism ofaction targeting serotonergic 5-HT_2A receptors while avoidingactivity at dopamine and other receptors commonly targeted by otherantipsychotics.

“Currently available treatments do not adequately address negativesymptoms of schizophrenia, which are highly prevalent and contributesignificantly to the long term disability and functional impairment ofpeople with this disease,” said Serge Stankovic, M.D., M.S.P.H.,ACADIA’s Executive Vice President, Head of Research and Development.“With its highly selective pharmacological profile, we believepimavanserin may address this unmet need and improve clinical outcomesfor these patients.”

About ADVANCE

ADVANCE is a Phase II, 26-week, randomized, double-blind,placebo-controlled, multi-center study designed to examine the efficacyand safety of adjunctive use of pimavanserin in patients withschizophrenia who have predominant negative symptoms. Approximately 380patients will be randomized to receive either pimavanserin or placebo,orally, once daily, in addition to their ongoing antipsychotic in aflexible dosing regimen. The starting daily dose of 20 mg ofpimavanserin at baseline may be adjusted to 34 mg or 10 mg during thefirst eight weeks of treatment. The primary endpoint of the study is thechange from baseline to week 26 on the Negative Symptom Assessment-16(NSA-16) total score. Following participation in ADVANCE, patients willbe eligible to enroll in a 52-week open-label extension study.

About Schizophrenia and Negative Symptoms

According to the National Institute of Mental Health, approximately onepercent of the U.S. population develops schizophrenia during theirlifetime. Schizophrenia is a chronic, debilitating mental illnesscharacterized by thought disorder, emotional and cognitive dysfunction,and behavioral disturbances. These disturbances may include positivesymptoms, such as hallucinations, delusions, and disorganized speech,and a range of negative symptoms, including flat affect, loss ofinterest, emotional withdrawal, and cognitive impairment. Studies showthat about 40 to 50 percent of schizophrenia patients suffer fromprominent negative symptoms. While currently available antipsychotictreatments for schizophrenia target positive symptoms, most patientsremain functionally impaired because of negative symptoms, cognitivedeficits and limited social function.

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 schizophrenia. 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 forthe adjunctive treatment of patients with negative symptoms ofschizophrenia.

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, includingwhether pimavanserin can treat the negative symptoms of schizophrenia orimprove clinical outcomes for patients experiencing such negativesymptoms. These statements are only predictions based on currentinformation 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,approval and commercialization, and in collaborations with others, andthe fact that past results of clinical trials may not be indicative offuture trial results. For a discussion of these and other factors,please refer to ACADIA’s annual report on Form 10-K for the year endedDecember 31, 2015 as well as ACADIA’s subsequent filings with theSecurities and Exchange Commission. You are cautioned not to place unduereliance on these forward-looking statements, which speak only as of thedate hereof. This caution is made under the safe harbor provisions ofthe Private Securities Litigation Reform Act of 1995. Allforward-looking statements are qualified in their entirety by thiscautionary statement and ACADIA undertakes no obligation to revise orupdate this press release to reflect events or circumstances after thedate hereof, except as required 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.

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