# EDGAR Filing Document

**Accession Number:** 0001070494
**File Stem:** 0001193125-26-197957
**Filing Date:** 2026-5
**Character Count:** 14689
**Document Hash:** a04a75c3571b3401375a3ff6bf14ad84
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-197957.hdr.sgml**: 20260501

**ACCESSION NUMBER**: 0001193125-26-197957

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 10

**CONFORMED PERIOD OF REPORT**: 20260427

**ITEM INFORMATION**: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

**ITEM INFORMATION**: Regulation FD Disclosure

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20260501

**DATE AS OF CHANGE**: 20260430

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** ACADIA PHARMACEUTICALS INC
- **CENTRAL INDEX KEY:** 0001070494
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 061376651
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 000-50768
- **FILM NUMBER:** 26927526

**BUSINESS ADDRESS:**
- **STREET 1:** 12830 EL CAMINO REAL
- **STREET 2:** SUITE 400
- **CITY:** SAN DIEGO
- **STATE:** CA
- **ZIP:** 92130
- **BUSINESS PHONE:** 858-558-2871

**MAIL ADDRESS:**
- **STREET 1:** 12830 EL CAMINO REAL
- **STREET 2:** SUITE 400
- **CITY:** SAN DIEGO
- **STATE:** CA
- **ZIP:** 92130

?xml version='1.0' encoding='ASCII'? 8-K

**UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549**

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## FORM 8-K

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**CURRENT REPORT**

**Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934**

**Date of Report (Date of earliest event reported):** April 27, 2026<br>

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Acadia Pharmaceuticals Inc.

**(Exact name of Registrant as Specified in Its Charter)**

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| | | |
|:---|:---|:---|
| Delaware | 000-50768 | 06-1376651 |
| **(State or Other Jurisdiction<br>of Incorporation)** | **(Commission File Number)** | **(IRS Employer<br>Identification No.)** |
| 12830 El Camino Real, Suite 400 |  |  |
| San Diego**,** California |  | 92130 |
| **(Address of Principal Executive Offices)** |  | **(Zip Code)** |

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**Registrant's Telephone Number, Including Area Code: (**858**)** 558-2871<br>

N/A<br>

**(Former Name or Former Address, if Changed Since Last Report)**

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Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

**Securities registered pursuant to Section 12(b) of the Act:**

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| | |
|:---|:---|
| **<br>Title of each class** | **<br>Name of each exchange on which registered** |
| Common Stock, par value $0.0001 per share<br> ACAD | The Nasdaq Stock Market LLC |

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Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

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. ☐

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## Item 5.02 Departure Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

## On April 27, 2026, Elizabeth H.Z. Thompson, Ph.D., Head of Research and Development, informed Acadia Pharmaceuticals Inc. (the "Company") of her planned retirement. Dr. Thompson has decided to retire for personal reasons. She has committed to continuing in her role as Head of Research and Development for a transitional period until a successor is appointed, after which she intends to remain with the Company as a consultant through the end of 2026, including through the planned readout of the Company's Phase 2 clinical study of remlifanserin in Alzheimer's disease psychosis. The Company has initiated a search for Dr. Thompson's replacement.

## Item 7.01 Regulation FD Disclosure.

## On April 30, 2026, the Company issued a press release announcing the planned retirement of Dr. Thompson. A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K.
As provided in General Instruction B.2 of Form 8-K, the information in this Item 7.01, including Exhibit 99.1 hereto, shall not be deemed to be "filed" for purposes of, or otherwise subject to the liabilities under, Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), nor shall such information or Exhibit 99.1 be deemed to be incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, whether made before or after the date hereof, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific reference in such a filing.

## *Forward-Looking Statements* 

## This Current Report on Form 8-K (this "Current Report") contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as "will," "continue," "intends" and similar expressions (as well as other words or expressions referencing future events, conditions or circumstances) are intended to identify forward-looking statements. These forward-looking statements are based on the Company's expectations and assumptions as of the date of this Current Report. Each of these forward-looking statements involves risks and uncertainties. Actual results may differ materially from these forward-looking statements. Forward-looking statements contained in this Current Report include, but are not limited to, statements regarding Dr. Thompson's anticipated retirement from the Company, her continuing to serve in her current role during a transitional period and as a consultant once a successor is appointed, and the Company's search for a replacement Head of Research and Development. Many factors may cause differences between current expectations and actual results, including the potential for Dr. Thompson to continue serving at the Company. Other factors that may cause actual results to differ from those expressed or implied in the forward-looking statements in this Current Report are discussed in the Company's filings with the Securities and Exchange Commission, including its Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and Current Reports on Form 8-K. Except as required by law, the Company assumes no obligation to update any forward-looking statements contained herein to reflect any change in expectations, even as new information becomes available.

## Item 9.01 Financial Statements and Exhibits.
**(d) Exhibits.** 

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| | |
|:---|:---|
| **Exhibit<br>Number** | **Description** |
| 99.1 | [<u>Press Release dated April 30, 2026.</u>](acad-ex99_1.htm) |
| 104 | Cover Page Interactive Data File (embedded within the Inline XBRL document). |

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**SIGNATURES**

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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| | | | |
|:---|:---|:---|:---|
|  |  |  | **Acadia Pharmaceuticals Inc.** |
| Date: | April 30, 2026 | By:  | /s/ Jennifer J. Rhodes |
|  |  |  | Jennifer J. Rhodes<br>Executive Vice President, Chief Legal Officer |

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## Exhibit 99.1

**Exhibit 99.1**

**<u>Acadia Pharmaceuticals Announces Planned Year-End Retirement of Elizabeth H.Z. Thompson, Ph.D., Head of Research and Development, Following a Distinguished Career</u>**

SAN DIEGO, Calif., April 30, 2026 — Acadia Pharmaceuticals Inc. (Nasdaq: ACAD) today announced the planned retirement of Elizabeth H.Z. Thompson, Ph.D., Head of Research and Development. Dr. Thompson has decided to retire for personal reasons and informed Acadia of her plans. She will continue in her role as Head of Research and Development until a successor is appointed. After her retirement, Acadia plans to retain Dr. Thompson as a consultant through at least the end of 2026 to ensure scientific and leadership continuity through the planned readout of the Phase 2 clinical study of remlifanserin in Alzheimer's disease psychosis (ADP) and into early Phase 3 clinical study execution.

Acadia has initiated a search for a new Head of Research and Development and is committed to identifying an experienced R&D leader who will build on the strong scientific foundation already in place. The Company continues to advance its clinical development programs as planned. All ongoing clinical trials, including the Phase 2 studies of remlifanserin in ADP and Lewy Body Dementia Psychosis (LBDP), continue to recruit and remain blinded, and the Company, including Dr. Thompson, does not yet know study outcomes.

"Liz's leadership has been instrumental in strengthening Acadia's research and development organization, both scientifically and operationally, and in advancing a clear, disciplined R&D strategy across our pipeline," said Catherine Owen Adams, Chief Executive Officer of Acadia. "She has been a strong advocate for the patients we serve and at every step has ensured thoughtful execution and prioritization of our programs in neurological and rare diseases. Just as importantly, Liz fostered a culture of clarity, accountability, and engagement across R&D. We are grateful for her continued commitment to Acadia during the transition period and for her willingness to remain engaged as a consultant, providing continuity of scientific leadership and institutional perspective in support of our mission and, most importantly, the patients we serve."

"Leading Acadia's research and development organization has been a defining chapter in my career and one in which I take a great deal of pride," said Dr. Thompson. "We started from a great foundation, and have been able to build and strengthen the Acadia R&D team as well as make good progress in shaping and advancing a curated pipeline. I am particularly pleased with how we've been able to strengthen the remlifanserin program, especially by expanding it into Lewy Body Dementia Psychosis. I remain excited by the potential for remlifanserin and confident in the disciplined development strategy the Acadia team is executing. Beyond remlifanserin, our pipeline contains multiple programs that could represent truly meaningful options for patients living with neurological and rare diseases. While I have decided to retire for personal reasons, I am committed to continuing to lead the organization until the appointment of a successor and to supporting Acadia through the transition and the remainder of the year."

Dr. Thompson joined Acadia in 2024 serving as Head of Research and Development. During her tenure, she helped strengthen the Company's scientific and clinical capabilities, advance multiple development programs, and foster a culture of collaboration across research, clinical development and regulatory teams.

About Acadia Pharmaceuticals

Acadia is committed to turning scientific promise into meaningful innovation that makes the difference for underserved neurological and rare disease communities around the world. Our commercial portfolio includes the first and only FDA-approved treatments for Parkinson's disease psychosis and Rett syndrome. We are developing the next wave of therapeutic advancements with a robust and diverse pipeline that includes mid- to late-stage programs in Alzheimer's disease psychosis and Lewy body dementia psychosis, along with earlier-stage programs that address other underserved patient needs. At Acadia, we're here to be their difference. For more information, visit us at acadia.com and follow us on LinkedIn and X.

Forward-Looking Statements

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This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Forward-looking statements include all statements other than statements of historical fact and can be identified by terms such as "may," "will," "should," "expects," "anticipates," "continues," "intends," "planned," and similar expressions (including the negative thereof) intended to identify forward-looking statements. Forward-looking statements contained in this press release, include, but are not limited to, statements about: (i) Dr. Thompson's planned retirement, and her continued service in her role through a transitional period and as a consultant with the Company, (ii) our ability to recruit and timely hire a new Head of Research and Development, and (iii) the advancement of the Company's clinical development programs, including the timely achievement of anticipated clinical milestones. Forward-looking statements are subject to known and unknown risks, uncertainties, assumptions and other factors that may cause our actual results, performance or achievements to differ materially and adversely from those anticipated or implied by our forward-looking statements. Such risks, uncertainties, assumptions and other factors include, but are not limited to Dr. Thompson's continued services to the Company, future executive recruitment and the advancement of clinical development programs. Given the risks and uncertainties, you should not place undue reliance on these forward-looking statements. For a discussion of these and other risks, uncertainties, assumptions and other factors that may cause our actual results, performance or achievements to differ, please refer to our annual report on Form 10-K for the year ended December 31, 2025 filed with the Securities and Exchange Commission on February 26, 2026, as well as our subsequent filings with the Securities and Exchange Commission from time to time. The forward-looking statements contained herein are made as of the date hereof, and we undertake no obligation to update them after this date, except as required by law.

Investor Contact:<br>Acadia Pharmaceuticals Inc.<br>Al Kildani<br>(858) 261-2872<br>ir@acadia-pharm.com

Acadia Pharmaceuticals Inc.<br>Jessica Tieszen<br>(858) 261-2950<br>ir@acadia-pharm.com

Media Contact:<br>Acadia Pharmaceuticals Inc.<br>Deb Kazenelson<br>(818) 395-3043<br>media@acadia-pharm.com

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