IMPROVING LIVES

ACADIA PHARMACEUTICALS INC. 2018 ANNUAL REPORT

ABOUT US We are a biopharmaceutical company focused on the development and commercialization of innovative medicines to address unmet medical needs in central nervous system disorders. We have developed and commercialized the first and only medicine approved for the treatment of hallucinations and delusions associated with Parkinson’s disease . We also have ongoing clinical development efforts in additional areas with significant unmet need, including dementia- related psychosis, inadequate response, schizophrenia-negative symptoms, major depressive disorder, and Rett syndrome.

To Our Stockholders occurs primarily in females following apparently normal development for the first six months of life. I want to thank you for your continued support of We plan to initiate a Phase 3 p������ evaluating our mission at ACADIA Pharmaceuticals. trofinetide as potential treatment for Rett syndrome in the fourth quarter of 2019. At ACADIA we are focused on three strategic pillars to achieve our mission. First is to grow NUPLAZID® Patients need truly innovative medicines that (pimavanserin) as the only approved treatment for improve their daily lives. We understand these patients with Parkinson’s disease psychosis (PDP). needs and are committed to developing medicines Second is to leverage the full potential of that make a meaningful difference. Our business development efforts are focused on licensing or pimavanserin by further examining its utility in acquiring novel therapeutic candidates or products several additional central nervous system (CNS) that address significant unmet needs for CNS disease states with high unmet needs. And third is to disorders. We have a talented and best-in class R&D expand our pipeline further through focused and commercial organization with extensive CNS business development in CNS disorders with high experience, making us an ideal partner for unmet needs. development and commercialization. In 2018 our team successfully executed on all three of our strategic pillars: We continue to keep patients and their caregivers at the forefront of our business decisions and look We Grew the Sales of NUPLAZID forward to an exciting year ahead. In 2018 we achieved net sales for the full year of $233.8 million, which represents a 79% increase over Thank you for your continuing interest in ACADIA the previous year. In 2018 the U.S. FDA approved a and the patients and caregivers we seek to serve. single 34-milligram capsule dose formulation of NUPLAZID. The introduction and adoption of the 34- milligram capsule has gone very well and we believe this will result in a more positive patient experience.

Given our continued growth in new patient starts, our continued expansion of our prescriber base, the introduction of the 34 milligram capsule, and NUPLAZID total bottle growth, we are confident in our ability to deliver upon the long-term commercial opportunity in PDP.

We Leveraged Pimavanserin in New Indications In 2018 we advanced our ongoing late-stage clinical trials designed to further evaluate the safety and of pimavanserin in patients with dementia- related psychosis, schizophrenia, and major depressive disorder. Notably, in October 2018 we reported robust positive results from our Phase 2 CLARITY study evaluating pimavanserin as an adjunctive therapy for patients with major Stephen R. Davis depressive disorder (MDD). Chief Executive Officer April 2019 We Expanded our Pipeline In 2018 we entered into a North American license agreement for trofinetide from Neuren Pharmaceuticals. Trofinetide is a novel synthetic analog of the amino-terminal tripeptide of IGF-1 designed to treat the core symptoms of Rett syndrome by reducing neuroinflammation and supporting synaptic function. Rett syndrome is a highly debilitating rare neurological disorder that

ACADIA PHARMACEUTICALS FORM 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 Form 10-K (Mark One) # ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2018 Or ! TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to Commission File Number: 000-50768 ACADIA PHARMACEUTICALS INC. (Exact Name of Registrant as Specified in Its Charter)

Delaware 06-1376651 (State or Other Jurisdiction of (I.R.S. Employer Incorporation or Organization) Identification Number) 3611 Valley Centre Drive, Suite 300 San Diego, California 92130 (Address of Principal Executive Offices) (Zip Code) Registrant’s telephone number, including area code: (858) 558-2871 Securities registered pursuant to Section 12(b) of the Act: Title of each class Name of each exchange on which registered Common Stock, par value $0.0001 per share The Nasdaq Global Select Market Securities registered pursuant to Section 12(g) of the Act: None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes # No ! Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. Yes ! No # Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes # No ! Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes # No ! Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of the registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ! Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See definitions of “large accelerated filer”, “accelerated filer”, “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Securities Exchange Act of 1934: Large accelerated filer # Accelerated filer ! Non-accelerated filer ! (Do not check if a smaller reporting company) Smaller reporting company ! Emerging growth company ! If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐ Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Securities Exchange Act of 1934). Yes ! No # As of June 29, 2018, the last business day of the registrant’s most recently completed second fiscal quarter, the aggregate market value of the registrant’s common stock held by non-affiliates of the registrant was approximately $1.2 billion, based on the closing price of the registrant’s common stock on the Nasdaq Global Select Market on June 29, 2018 of $15.27 per share. As of January 31, 2019, 143,882,381 shares of the registrant’s common stock, $0.0001 par value, were outstanding. DOCUMENTS INCORPORATED BY REFERENCE Portions of the registrant’s definitive Proxy Statement to be filed with the Securities and Exchange Commission by April 30, 2019 are incorporated by reference into Part III of this report. [THIS PAGE INTENTIONALLY LEFT BLANK] ACADIA PHARMACEUTICALS INC. TABLE OF CONTENTS FOR