False 0001520262 Alkermes plc. 0001520262 2025-10-28 2025-10-28

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT
PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of Report (Date of earliest event reported): October 28, 2025

ALKERMES PUBLIC LIMITED COMPANY

(Exact name of registrant as specified in its charter)

Ireland |  | 001-35299 |  | 98-1007018
(State or other jurisdiction |  | (Commission |  | (IRS Employer
of incorporation) |  | File Number) |  | Identification No.)
Connaught House, 1 Burlington Road
Dublin 4, Ireland D04 C5Y6
(Address of principal executive offices)

Registrant's telephone number, including area code: + 353-1-772-8000

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 (see General Instruction A.2. below):

☐ |  | 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:

Title of each class |  | Trading Symbol(s) |  | Name of each exchange on which registered
Ordinary shares, $0.01 par value |  | ALKS |  | Nasdaq Global Select Market

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. ☐

Item 2.02 Results of Operations and Financial Condition.

On October 28, 2025, Alkermes plc (the “Company”) announced financial results for the three and nine months ended September 30, 2025 and updated financial expectations for the year ending December 31, 2025. Copies of the related press release and the investor presentation to be displayed during the Company’s conference call on October 28, 2025 discussing such financial results and updated financial expectations are furnished herewith as Exhibit 99.1 and Exhibit 99.2, respectively. This information, including Exhibits 99.1 and 99.2, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

EXHIBIT INDEX

Exhibit No. |  | Description
99.1 |  | Press release issued by Alkermes plc on October 28, 2025 announcing financial results for the three and nine months ended September 30, 2025 and updating financial expectations for the year ending December 31, 2025.
99.2 |  | Investor presentation to be displayed by Alkermes plc on October 28, 2025.
104 |  | Cover page interactive data file (embedded within the Inline XBRL document).

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SIGNATURE

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.

| ALKERMES PLC
Date: October 28, 2025 | By: |  | /s/ Joshua Reed
|  |  | Joshua Reed
|  |  | Senior Vice President, Chief Financial Officer (Principal Financial Officer)

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