Dr. Joseph Friedman to Present Data From ACADIA Pharmaceuticals’ First Phase III Trial With Pimavanserin for Parkinson’s Disease Psychosis at the 62nd American Academy of Neurology Annual Meeting

SAN DIEGO, Apr 14, 2010 (BUSINESS WIRE) –ACADIA Pharmaceuticals Inc. (Nasdaq: ACAD), a biopharmaceutical company utilizing innovative technology to fuel drug discovery and clinical development of novel treatments for central nervous system disorders, today announced that Joseph H. Friedman, MD, will present data from ACADIA’s previously reported Phase III trial (the -012 Study) with pimavanserin for Parkinson’s disease psychosis (PDP) at the 62nd American Academy of Neurology Annual Meeting on April 14, 2010 in Toronto, Canada. Dr. Friedman is Professor and Chief, Division of Movement Disorders, Department of Neurology, Warren Alpert Medical School Brown University, and the Director of the Neurohealth Parkinson’s Disease and Movement Disorders Center in Warwick, Rhode Island. He is an established expert in Parkinson’s disease and was one of the lead investigators in the -012 Study.

In an oral presentation entitled “A multi-center, placebo-controlled, double-blind trial to examine the safety and efficacy of pimavanserin in the treatment of psychosis in Parkinson’s disease,” Dr. Friedman will discuss data from the trial in which two doses of pimavanserin, 10 mg and 40 mg, were tested against placebo. The primary end point of the study was antipsychotic efficacy as measured using the Scale for the Assessment of Positive Symptoms, or SAPS. As previously reported, all study arms showed marked improvements in mean SAPS scores but neither of the active arms showed a statistically significant separation from placebo at the end of the six-week treatment period. Although statistical significance was not achieved for the primary endpoint, the 40 mg pimavanserin arm consistently demonstrated signals of efficacy across a number of measures including the SAPS, CGI-I, SCOPA nighttime sleep measure, and caregiver burden scale.

As previously reported, the study met its key secondary endpoint of motoric tolerability as measured using the Unified Parkinson’s Disease Rating Scale, or UPDRS, and Dr. Friedman will present additional data demonstrating that pimavanserin was safe and well tolerated with the frequency of adverse events generally similar in the pimavanserin and placebo arms.

“Having completed the analysis of the -012 Study, we have used the findings from that study to design a new, U.S.-focused Phase III study, ACP-103-020, which will test 40 mg of pimavanserin versus placebo and which is scheduled to start around mid-year” said Uli Hacksell, PhD, Chief Executive Officer of ACADIA. “The Phase III data from the -012 Study support the safety and tolerability of pimavanserin in patients suffering from PDP and we are optimistic that the design of the ACP-103-020 study will reduce the placebo response and help ensure that the primary endpoint of antipsychotic efficacy will be reached.”

About Pimavanserin

Pimavanserin is a 5-HT_2A receptor inverse agonist in Phase III development as a treatment for Parkinson’s disease psychosis. This new chemical entity, which was discovered by ACADIA, is a small molecule that can be taken orally as a tablet once-a-day. ACADIA and Biovail Laboratories International SRL (Biovail), a subsidiary of Biovail Corporation, have formed a collaboration to co-develop and commercialize pimavanserin for neurological and psychiatric indications, including schizophrenia, Parkinson’s disease psychosis and Alzheimer’s disease psychosis, in the United States and Canada. ACADIA retains rights to pimavanserin in the rest of the world.

About Parkinson’s Disease Psychosis

According to the National Parkinson Foundation, over 1.5 million people in the United States suffer from Parkinson’s disease. Up to 40 percent of patients with Parkinson’s disease may develop psychotic symptoms, commonly consisting of visual hallucinations and delusions. Currently there is no therapy in the United States approved to treat PDP. The development of psychosis in patients with Parkinson’s disease is associated with increased caregiver burden, nursing home placement, and increased mortality.

About ACADIA Pharmaceuticals

ACADIA is a biopharmaceutical company utilizing innovative technology to fuel drug discovery and clinical development of novel treatments for central nervous system disorders. ACADIA is currently developing a portfolio consisting of four product candidates including pimavanserin, which is being developed for three separate neurological and psychiatric indications in collaboration with Biovail. These indications are Parkinson’s disease psychosis, which is in Phase III development, adjunctive therapy for schizophrenia, which is in Phase III planning, and Alzheimer’s disease psychosis, for which ACADIA is planning to initiate a Phase II feasibility study. In addition to pimavanserin, ACADIA has a product candidate in Phase II for chronic pain and a product candidate in Phase I for glaucoma, both in collaboration with Allergan, as well as a product candidate for schizophrenia in IND-track development in collaboration with Meiji Seika Kaisha. All of the product candidates in ACADIA’s pipeline emanate from discoveries made using its proprietary drug discovery platform. ACADIA maintains a website at http://cts.businesswire.com/ct/CT?id=smartlink&url=http%3A%2F%2Fwww.acadia-pharm.com&esheet=6248420&lan=en_US&anchor=www.acadia-pharm.com&index=1&md5=bd17a553c4ed3fb0d4e7858798ed1e97 to which ACADIA regularly posts copies of its press releases as well as additional information and through which interested parties can subscribe to receive email alerts.

Forward-Looking Statements

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 drug discovery and development programs, including clinical trials and the results therefrom, and the potential of and the benefits to be derived from product candidates, in each case including pimavanserin. 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, commercialization and collaborations with others, and the fact that past results of clinical trials may not be indicative of further 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, 2009 as well as ACADIA’s subsequent filings with the Securities and Exchange Commission. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. This caution is made under the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. All forward-looking statements are qualified in their entirety by this cautionary statement and ACADIA undertakes no obligation to revise or update this press release to reflect events or circumstances after the date hereof, except as required by law.

SOURCE: ACADIA Pharmaceuticals Inc.