ACAD Acadia Pharmaceuticals Inc

On September 9, 2019, the Company announced that its Phase 3 HARMONY study, a double-blind, placebo-controlled relapse prevention study of pimavanserin for the treatment of hallucinations and delusions associated with dementia-related psychosis, met its primary endpoint, demonstrating a highly statistically significant longer time to relapse of psychosis with pimavanserin compared to placebo in a planned interim efficacy analysis. Upon the recommendation of the study’s independent data monitoring committee, which met to review the data from the planned interim efficacy analysis, the study will now be stopped early based on pre-specified stopping criteria requiring a one-sided p-value less than 0.0033 on the study’s primary endpoint.

The Company is planning to meet with the FDA regarding a supplemental NDA submission in 2020 and the results from the HARMONY study will be submitted for presentation at upcoming medical meetings.

The HARMONY study included a 12-week open-label stabilization period during which patients with dementia-related psychosis were treated with pimavanserin 34 mg once daily. Dose reduction to 20 mg once daily was allowed if clinically justified within the first four weeks. Following the 12-week stabilization period, patients who met pre-specified criteria for treatment response were then randomized into the double-blind period of the study to continue their pimavanserin dose (34 mg or 20 mg per day) or switched to placebo and followed for up to 26 weeks or until a relapse of psychosis occurred. The primary endpoint in the study was time to relapse in the double-blind period. Relapse (significant worsening of dementia-related psychosis after prior stabilization) was defined in the study by one or more of the following: hospitalization due to dementia-related psychosis, significant deterioration of dementia-related symptoms on clinical scales, withdrawal from the study due to lack of efficacy, or the use of an off-label antipsychotic medication for the treatment of dementia-related delusions and/or hallucinations. All potential relapses and discontinuations in the double-blind portion of the study were adjudicated by an independent adjudication committee to determine if protocol defined relapse criteria were met.

A copy of ACADIA’s press release issued September 9, 2019 is furnished herewith as Exhibit 99.1.

Forward-Looking Statements

Statements in this Current Report that are not strictly historical in nature are forward-looking statements. These statements include, but are not limited to, statements related to: intended activities with respect to the HARMONY study following the interim analysis, expected timelines with respect to full data from the HARMONY study and the Company’s planned engagement with the FDA. 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 development, approval and commercialization, 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 the Company’s annual report on Form 10-K for the year ended December 31, 2018 as well as its 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 the Company undertakes no obligation to revise or update this press release to reflect events or circumstances after the date hereof, except as required by law.