LNTH

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EX-99.1

2 lnth-ex99_1.htm

EX-99.1

EX-99.1

Exhibit 99.1

Lantheus Reports First Quarter 2026 Financial Results and Provides Business Update

• Strong start to the year with worldwide revenue of $377.3 million in the first quarter 2026

• GAAP fully diluted earnings per share of $1.80, compared to $1.02 in the first quarter of 2025

• Adjusted fully diluted earnings per share of $1.46, compared to $1.53 in the first quarter of 2025

• FDA approves PYLARIFY TruVuTM (piflufolastat F18); phased geographic launch planned to begin in the fourth quarter of 2026

• FDA tentative approval for Lutetium Lu 177 Dotatate (PNT2003); expected to be the first radioequivalent for the treatment of gastroenteropancreatic neuroendocrine tumors

• Reaffirmed previously issued corporate guidance for full year 2026 revenue and adjusted fully diluted earnings per share

BEDFORD, Mass., May 7, 2026 (GLOBE NEWSWIRE) -- Lantheus Holdings, Inc. (Lantheus or the Company) (NASDAQ: LNTH), the leading radiopharmaceutical-focused company committed to enabling clinicians to Find, Fight and Follow disease to deliver better patient outcomes, today reported financial results for its first quarter ended March 31, 2026.

“Our first quarter results demonstrate disciplined execution across the business, with strong performance from PYLARIFY, Neuraceq, and DEFINITY, and continued progress against the priorities that underpin our long-term strategy,” said Mary Anne Heino, Chief Executive Officer of Lantheus. “During the quarter, we secured FDA approval for PYLARIFY TruVu and achieved tentative approval for PNT2003. For the remainder of 2026, we are focused on sustaining our leadership in PSMA PET as we prepare for the PYLARIFY TruVu conversion later this year, expanding our Alzheimer’s imaging portfolio, and advancing our prioritized pipeline. At the same time, we will remain disciplined in our capital deployment, prioritizing radiodiagnostics while evaluating the best path to maximize value from our radiotherapeutic assets – all as we lay the groundwork for growth acceleration beginning in 2027.”

Summary Financial Results

Three Months Ended March 31,

(in millions, except per share data - unaudited)

2026

2025

% Change

Worldwide revenue

$

377.3

$

372.8

1.2

%

GAAP net income

$

118.4

$

72.9

62.3

%

GAAP fully diluted earnings per share

$

1.80

$

1.02

76.5

%

Adjusted net income (non-GAAP)

$

95.8

$

109.5

(12.5

%)

Adjusted fully diluted earnings per share (non-GAAP)

$

1.46

$

1.53

(4.6

%)

First Quarter 2026

• Worldwide revenue increased 1.2% to $377.3 million compared to the same period in 2025.

• Sales of PYLARIFY were $240.9 million, a decrease of 6.5%.

• Sales of Neuraceq were $35.4 million.

• Sales of DEFINITY were $84.6 million, an increase of 6.8%.

• Operating income decreased 20.3% to $81.3 million. Adjusted operating income (non-GAAP) decreased 10.5% to $129.1 million.

Page 1 of 11

• Fully diluted earnings per share increased 76.5% to $1.80, compared to fully diluted earnings per share of $1.02 in the prior year period. Adjusted fully diluted earnings per share (non-GAAP) decreased 4.6% to $1.46, compared to $1.53 in the prior year period.

• Net cash provided by operating activities and free cash flow were $125.1 million and $121.9 million, respectively.

Balance Sheet

• At March 31, 2026, the Company's cash and cash equivalents were $498.6 million, including proceeds of $31.4 million from the sale of the Company’s single-photon emission computerized tomography (“SPECT”) business to SHINE Technologies, LLC (“SHINE”) on January 1, 2026, compared to $359.1 million at December 31, 2025.

• The Company currently has access to up to $750.0 million from a revolving line of credit.

Recent Business Highlights

• Received FDA approval for PYLARIFY TruVuTM (piflufolastat F18), a new formulation of PYLARIFY®, the Company’s market‑leading PSMA PET imaging agent, designed to enhance manufacturing efficiency and supply flexibility; a phased geographic commercial launch is planned to begin in the fourth quarter of 2026 to align with coding, coverage, payment, and customer and PMF readiness.

• Completed the divestiture of the legacy SPECT business to SHINE (effective January 1, 2026), a decisive action taken to focus on PET radiodiagnostics and simplify the Company’s operating model.

• Achieved FDA tentative approval for PNT2003, which upon full approval would be the first radioequivalent to Lutetium Lu 177 Dotatate for the treatment of gastroenteropancreatic neuroendocrine tumors (GEP‑NETs); launch timing will consider the following factors: the timing of FDA approval, the expiration of the 30‑month Hatch‑Waxman stay and disposition of the related legal proceedings, as well as manufacturing and commercial strategy to ensure launch success.

• The FDA extended the PDUFA date for LNTH‑2501(Ga 68 edotreotide), the Company’s PET diagnostic imaging kit for somatostatin receptor‑positive neuroendocrine tumors (NETs),

8-K

0001521036false00015210362026-02-262026-02-26

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): February 26, 2026

LANTHEUS HOLDINGS, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware

001-36569

35-2318913

(State or Other Jurisdiction of Incorporation)

(Commission File Number)

(IRS Employer Identification No.)

201 Burlington Road South Building

Bedford, Massachusetts

01730

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s Telephone Number, Including Area Code: (978) 671-8001

Not Applicable

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

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:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common stock, par value $0.01 per share

LNTH

The Nasdaq Global 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 February 26, 2026, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and twelve months ended December 31, 2025. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, except as shall be expressly set forth by specific reference in such filing. Item 9.01 Financial Statements and Exhibits. (d) Exhibits

Exhibit No.

Description

99.1*

Press release of Lantheus Holdings, Inc. dated February 26, 2026, entitled “Lantheus Reports Fourth Quarter and Full Year 2025 Financial Results and Provides Business Update”

104

Cover Page Interactive Data File (embedded within the Inline XBRL document)

* Exhibits 99.1 attached hereto are being furnished and shall not be deemed “filed” for purposes of Section 18 of the Exchange Act, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act or the Exchange Act, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By:

/s/ Daniel M. Niedzwiecki

Name:

Daniel M. Niedzwiecki

Title:

Chief Administrative Officer and General Counsel

Date: February 26, 2026

8-K

0001521036false00015210362025-10-312025-10-31

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 31, 2025

LANTHEUS HOLDINGS, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware

001-36569

35-2318913

(State or Other Jurisdiction of Incorporation)

(Commission File Number)

(IRS Employer Identification No.)

201 Burlington Road South Building

Bedford, Massachusetts

01730

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s Telephone Number, Including Area Code: (978) 671-8001

Not Applicable

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

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:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common stock, par value $0.01 per share

LNTH

The Nasdaq Global 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 November 6, 2025, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and nine months ended September 30, 2025. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, except as shall be expressly set forth by specific reference in such filing. Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers On November 6, 2025, the Company announced that Brian Markison, the Company’s Chief Executive Officer and a member of the Company’s board of directors (the “Board”), notified the Board on November 2, 2025, that he will retire from the Company effective December 31, 2025 (the “Effective Date”). In connection with his retirement and in accordance with the terms of his employment agreement with the Company, Mr. Markison will also resign from the Board on the Effective Date. Mr. Markison’s decision to retire from all positions held at the Company is not related to any disagreement with the Company on any matter relating to its operations, policies, or practices. Mr. Markison has agreed to serve as a strategic advisor to the Company through at least March 31, 2026. The Company has also announced that Mary Anne Heino, the Chair of the Board, has been appointed Executive Chair of the Company effective on November 7, 2025 (the “Appointment Date”) and will serve as the Company’s principal executive officer as of the Appointment Date. In addition, the Board appointed Ms. Heino as the Company’s Interim Chief Executive Officer effective on January 1, 2026. Ms. Heino, 65, has served as a member of the Board since August 2015, and became the Chair of the Board and a member of the Science and Technology Committee in March 2024. She previously served in the following roles at the Company: Chief Executive Officer from August 2015 until March 1, 2024; President from August 2015 until March 2023; Chief Operating Officer from March 2015 until August 2015; and Chief Commercial Officer from April 2013 (when she joined the Company) until March 2015. Ms. Heino was not selected as Executive Chair or Interim Chief Executive Officer pursuant to any arrangement or understanding between her and any other person. There are no related party transactions between the Company and Ms. Heino, except that she

8-K

0001521036false00015210362025-08-062025-08-06

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): August 06, 2025

LANTHEUS HOLDINGS, INC.

(Exact name of Registrant as Specified in Its Charter)

Delaware

001-36569

35-2318913

(State or Other Jurisdiction of Incorporation)

(Commission File Number)

(IRS Employer Identification No.)

201 Burlington Road South Building

Bedford, Massachusetts

01730

(Address of Principal Executive Offices)

(Zip Code)

Registrant’s Telephone Number, Including Area Code: (978) 671-8001

Not Applicable

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

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:

Title of each class

Trading Symbol(s)

Name of each exchange on which registered

Common stock, par value $0.01 per share

LNTH

The Nasdaq Global 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 August 6, 2025, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and six months ended June 30, 2025. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended (the “Securities Act”), or the Exchange Act, except as shall be expressly set forth by specific reference in such filing. Item 7.01 Regulation FD Disclosure. On August 6, 2025, the Company issued a press release announcing that the United States Food and Drug Administration has accepted a new drug application for a new formulation of its piflufolastat F-18 prostate-specific membrane antigen positron emission tomography imaging agent filed by its affiliate, Aphelion LLC. A copy of the press release is being furnished with this Current Report on Form 8-K as Exhibit 99.2 and is incorporated herein by reference. The information in this Item 7.01, including Exhibit 99.2, shall not be deemed “filed” for purposes of Section 18 of the Exchange Act or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act or the Exchange Act, except as shall be expressly set forth by specific reference in such filing. Item 8.01 Other Events. On August 6, 2025, the Company announced that its board of directors has authorized a program to repurchase up to $400.0 million of shares of its common stock through December 31, 2027 (the “2025 Program”). The 2025 Program replaces the Company’s existing repurchase program, which was announced in November 2024. Repurchases under the 2025 Program may be made from time to time through open market transactions at prevailing market prices, in privately negotiated transactions and/or through other legally permissible means, depending on market conditions and in accordance with applicable rules and regulations. The actual timing, number, and dollar amount of repurchase transactions will be determined by the Company’s management at its discretion and will depend on a number of factors including, but not limited to, the market price of the Company’s common stock. The Company may also establish 10b5-1 trading plans from time to time that will provide flexibility if and when it buys back its common stock. The announcement of the 2025 Program is included in the press release attached hereto as Exhibit 99.1.

Safe Harbor for Forward-Looking and Cautio

lnth-20250507FALSE000152103600015210362025-05-072025-05-07

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): May 7, 2025

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

201 Burlington Road, South Building, Bedford, MA 01730 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 May 7, 2025, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three months ended March 31, 2025. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated May 7, 2025, entitled "Lantheus Reports First Quarter 2025 Financial Results and Provides Business Update"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Exchange Act, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Chief Administrative Officer and General Counsel

Date: May 7, 2025

lnth-20250226FALSE000152103600015210362025-02-262025-02-26

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): February 26, 2025

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

201 Burlington Road, South Building, Bedford, MA 01730 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 February 26, 2025, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and twelve months ended December 31, 2024. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated February 26, 2025, entitled "Lantheus Reports Fourth Quarter and Full Year 2024 Financial Performance"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Exchange Act, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Chief Administrative Officer and General Counsel

Date: February 26, 2025

8-K

false 0001521036 0001521036 2025-01-27 2025-01-27

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): January 27, 2025

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware

001-36569

35-2318913

(State or other jurisdiction of incorporation)

(Commission File Number)

(IRS Employer Identification No.)

201 Burlington Road, South Building Bedford, Massachusetts 01730 (Address of principal executive offices) (Zip code) Registrant’s telephone number, including area code: (978) 671-8001 Not Applicable (Former name or former address, if changed since last report.)

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

Common stock, par value $0.01 per share

LNTH

The Nasdaq Global 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 1.01 Entry into a Material Definitive Agreement.

On January 27, 2025, Lantheus Medical Imaging, Inc., a Delaware corporation (“Lantheus Medical”) and wholly-owned subsidiary of Lantheus Holdings, Inc., a Delaware corporation (“Lantheus” or the “Company”), and Project Hazel Merger Sub, Inc., a Delaware corporation and wholly-owned subsidiary of Lantheus Medical (“Merger Sub”), entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Evergreen Theragnostics, Inc., a Delaware corporation (“Evergreen”), Shareholder Representative Services LLC, a Colorado limited liability company, solely in its capacity as the representative, agent and attorney-in-fact of the Indemnitors (the “Securityholders’ Representative”) and Lantheus, solely for the purposes of Section 11.2 of the Merger Agreement, pursuant to which Lantheus Medical will acquire Evergreen by means of a statutory merger of Merger Sub with and into Evergreen, with Evergreen surviving as a wholly-owned subsidiary of Lantheus Medical (the “Merger”). Evergreen is a clinical-stage radiopharmaceutical company engaged in Contract Development and Manufacturing (CDMO) services as well as drug discovery and commercialization of proprietary products. Pursuant to the Merger Agreement, Lantheus Medical will pay (i) an upfront amount of $250 million, payable in cash at closing and subject to customary adjustments as set forth in the Merger Agreement and (ii) milestone payments in an aggregate additional cash amount of up to $752.5 million upon the occurrence of certain Milestone Trigger Events (as set forth in the Merger Agreement) (clauses (i) and (ii), the “Merger Consideration”). Under the terms of the Merger Agreement, all issued and outstanding Evergreen common stock (other than cancelled shares and dissenting shares), all outstanding and unexercised, whether vested or unvested, Evergreen options and all Evergreen restricted stock units, whether vested or unvested, that are outstanding and unsettled immediately prior to the closing of the Merger shall be canceled in exchange for the Merger Consideration as set forth in the Merger Agreement. For a specified period following the closing of the Merger, subject to certain specified exceptions, Lantheus Medical has agreed to use commercially reasonable efforts to (i) seek regulatory approval for and commercialize OCTEVYTM in the United States and (ii) develop and commercialize certain other product candidates of Evergreen that are the subject of the milestone obligations. The Merger Agreement contains customary representations, warranties, covenants and obligations of each of the parties to the Merger Agreement. The Merger Agreement also contains customary indemnification provisions whereby the Evergreen securityholders will indemnify Lantheus Medical for certain damages arising out of inaccuracies in, or breaches

lnth-20241106FALSE000152103600015210362024-11-062024-11-06

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): November 6, 2024

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

201 Burlington Road, South Building, Bedford, MA 01730 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 November 6, 2024, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and nine months ended September 30, 2024. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated November 6, 2024, entitled "Lantheus Reports Third Quarter 2024 Financial Results"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Exchange Act, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Chief Administrative Officer and General Counsel

Date: November 6, 2024

lnth-20240731FALSE000152103600015210362024-07-312024-07-31

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): July 31, 2024

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

201 Burlington Road, South Building, Bedford, MA 01730 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 July 31, 2024, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and six months ended June 30, 2024. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated July 31, 2024, entitled "Lantheus Reports Second Quarter 2024 Financial Results"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Exchange Act, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Chief Administrative Officer and General Counsel

Date: July 31, 2024

lnth-20240502FALSE000152103600015210362023-11-022023-11-02

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): May 2, 2024

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

201 Burlington Road, South Building, Bedford, MA 01730 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 May 2, 2024, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three months ended March 31, 2024. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated May 2, 2024, entitled "Lantheus Reports First Quarter 2024 Financial Results"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Exchange Act, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Chief Administrative Officer and General Counsel

Date: May 2, 2024

lnth-20240222FALSE000152103600015210362024-02-222024-02-22

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): February 22, 2024

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

201 Burlington Road, South Building, Bedford, MA 01730 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 February 22, 2024, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and twelve months ended December 31, 2023. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated February 22, 2024, entitled "Lantheus Reports Fourth Quarter and Full Year 2023 Financial Results"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Exchange Act, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Eric Green Name: Eric Green Title: Vice President and Deputy General Counsel

Date: February 22, 2024

lnth-20240109FALSE000152103600015210362023-02-232023-02-23

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): January 9, 2024

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

201 Burlington Road, South Building, Bedford, MA 01730 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 January 9, 2024, Lantheus Holdings, Inc. (the “Company”) announced via press release certain unaudited financial results for the twelve months ended December 31, 2023. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated January 9, 2024, entitled "Lantheus Reports Preliminary Fiscal Year 2023 Revenue"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto are being furnished and shall not be deemed “filed” for purposes of Section 18 of the Exchange Act, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Chief Administrative Officer and General Counsel

Date: January 9, 2024

lnth-20231102FALSE000152103600015210362023-11-022023-11-02

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): November 2, 2023

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

201 Burlington Road, South Building, Bedford, MA 01730 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 November 2, 2023, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and nine months ended September 30, 2023. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated November 2, 2023, entitled "Lantheus Reports Third Quarter 2023 Financial Results"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Exchange Act, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Chief Administrative Officer and General Counsel

Date: November 2, 2023

lnth-20230802FALSE000152103600015210362023-02-232023-02-23

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): August 2, 2023

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

201 Burlington Road, South Building, Bedford, MA 01730 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 August 3, 2023, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and six months ended June 30, 2023. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 7.01.     Regulation FD. On August 3, 2023, the Company issued a press release announcing the sale of its RELISTOR net sales royalties. A copy of the press release is being furnished with this Current Report on Form 8-K as Exhibit 99.2 and is incorporated herein by reference. The information in this Item 7.01 and Exhibit 99.1 attached hereto are intended to be furnished and shall not be deemed “filed” for any purpose, including for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, nor shall they be deemed incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such filing. Item 8.01.     Other Events. On August 2, 2023, the Company’s wholly owned subsidiary Progenics Pharmaceuticals, Inc., entered into a Royalty Interest Acquisition Agreement with HealthCare Royalty ("HCRx"). Under the terms of the agreement, the Company received an initial payment of approximately $98.0 million and has the right to receive an additional payment of $5.0 million from HCRx if worldwide net sales of RELISTOR in 2025 exceed a specified threshold. In exchange for the payment, HCRx received the rights to the tiered, sales-based royalties on worldwide net sales of RELISTOR related to the second quarter of 2023 and subsequent quarters. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated August 3, 2023, entitled "Lantheus Reports Second Quarter 2023 Financial Results"

99.2*Press release of Lantheus Holdings, Inc. dated August 3, 2023, entitled "Lantheus Announces Agreement to Sell RELISTOR® Royalties to HealthCare Royalty"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 and 99.2 attached hereto are being furnished and shall not be deemed “filed” for purposes of Section 18 of the Exchange Act, as amended, or otherwise subject to the liabilities of that section, nor shall such informat

lnth-20230504FALSE000152103600015210362023-02-232023-02-23

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): May 4, 2023

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

201 Burlington Road, South Building, Bedford, MA 01730 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 May 4, 2023, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three months ended March 31, 2023. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated May 4, 2023, entitled "Lantheus Reports First Quarter 2023 Financial Results"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Chief Administrative Officer and General Counsel

Date: May 4, 2023

lnth-20230223FALSE000152103600015210362023-02-232023-02-23

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): February 23, 2023

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

201 Burlington Road, South Building, Bedford, MA 01730 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 February 23, 2023, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and twelve months ended December 31, 2022. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated February 23, 2023, entitled "Lantheus Reports Fourth Quarter and Full Year 2022 Financial Results"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Senior Vice President and General Counsel

Date: February 23, 2023

lnth-20221103FALSE000152103600015210362022-04-292022-04-29

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): November 3, 2022

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

331 Treble Cove Road, North Billerica, MA 01862 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 November 3, 2022, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and nine months ended September 30, 2022. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated November 3, 2022, entitled "Lantheus Reports Third Quarter 2022 Financial Results"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Senior Vice President and General Counsel

Date: November 3, 2022

lnth-20220804FALSE000152103600015210362022-04-292022-04-29

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): August 4, 2022

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

331 Treble Cove Road, North Billerica, MA 01862 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 August 4, 2022, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three and six months ended June 30, 2022. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated August 4, 2022, entitled "Lantheus Reports Second Quarter 2022 Financial Results"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Senior Vice President and General Counsel

Date: August 4, 2022

lnth-20220429FALSE000152103600015210362022-04-292022-04-29

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): April 29, 2022

LANTHEUS HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3656935-2318913 (State or other jurisdiction of incorporation)(Commission File Number)(IRS Employer Identification No.)

331 Treble Cove Road, North Billerica, MA 01862 (Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (978) 671-8001

Not Applicable

(Former name or former address, if changed since last report.)

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 classTrading Symbol(s)Name of each exchange on which registered Common stock, par value $0.01 per shareLNTHThe Nasdaq Global 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 April 29, 2022, Lantheus Holdings, Inc. (the “Company”) announced via press release its financial results as of and for the three months ended March 31, 2022. A copy of that press release is being furnished as Exhibit 99.1 and is hereby incorporated by reference. The information furnished pursuant to this Item 2.02, including Exhibit 99.1, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities under that Section and shall not be deemed to be incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Exchange Act. Item 9.01.    Financial Statements and Exhibits. (d) Exhibits

Exhibit No.Description 99.1*Press release of Lantheus Holdings, Inc. dated April 29, 2022, entitled "Lantheus Holdings, Inc. Reports First Quarter 2022 Financial Results"

104Cover Page Interactive Data File (embedded within the Inline XBRL document)

*    Exhibit 99.1 attached hereto is being furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to the liabilities of that section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

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.

LANTHEUS HOLDINGS, INC.

By: /s/ Daniel M. Niedzwiecki Name: Daniel M. Niedzwiecki Title: Senior Vice President and General Counsel

Date: April 29, 2022