On August 3, 2026, the Company entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Curium US Holdings LLC (the “Parent”) and Coco Merger Sub Inc. (the “Merger Sub”), pursuant to which the Parent will acquire the Company by means of a statutory merger of the Merger Sub with and into the Company, with the Company surviving as the Parent’s wholly-owned subsidiary (the “Merger”). See Note 19, “Subsequent Event,” for more information on the Merger.

On April 1, 2025 (the “ Evergreen Closing Date”), the Company acquired all the issued and outstanding shares of Evergreen by means of a statutory merger of a subsidiary of the Company with and into Evergreen, with Evergreen surviving as the Company’s wholly-owned subsidiary (the “Evergreen Acquisition”), pursuant to the terms of the Evergreen Merger Agreement. Evergreen is a clinical-stage radiopharmaceutical company engaged in contract development and manufacturing organization services as well as drug discovery and commercialization of proprietary products.

As consideration for the Evergreen Acquisition, the Company made an upfront payment of $276.4 million in cash. The upfront cash consideration included a $25.0 million milestone payment that was triggered prior to the Evergreen Closing Date, the cash settlement of the options and restricted stock units granted to certain Evergreen equity holders related to pre-acquisition services, which was recorded as a component of consideration transferred of $6.1 million, the settlement by the Company of the pre-existing Evergreen debt of $4.3 million, and the payment of transaction expenses paid by the Company on behalf of Evergreen of $11.6 million. In connection with the Evergreen Acquisition, certain equity awards that were outstanding and unvested prior to the acquisition became fully vested per terms of the merger agreement. The Company recognized $7.5 million of nonrecurring post-combination expense related to the acceleration and cash settlement of

unvested historical Evergreen employee stock awards, which was recorded to operating expenses in the Company’s consolidated statements of operations in 2025.

In the event of achievement of specified milestones, the Company would be required to pay up to an additional $727.5 million in cash pursuant to the Evergreen Merger Agreement. The potential remaining milestone payments are accounted for as contingent consideration, the fair value of which is determined using a Monte Carlo simulation for sales milestones and a probability-weighted DCF approach for development and commercialization milestones. The fair value of the total contingent consideration is included in long-term contingent consideration liabilities, net of current portion in the Company’s condensed consolidated balance sheets at June 30, 2026.

The Evergreen Acquisition was accounted for as an acquisition of a business under ASC 805, “Business Combinations (“ASC 805”),” which requires that assets acquired and liabilities assumed on the acquisition date be recognized at their fair values as of the acquisition date. While the Company uses its best estimates and assumptions as part of the purchase price allocation process to value the assets acquired and liabilities assumed, its estimates and assumptions are subject to change during the measurement period, which is up to one year from the acquisition date. Fair value estimates are based on a complex series of judgments about future events and uncertainties and relies on estimates and assumptions. The judgments used to determine the estimated fair value assigned to each class of assets acquired and liabilities assumed, as well as asset lives, can materially impact the Company’s condensed consolidated statements of operations.

The purchase accounting for the Evergreen Acquisition has been finalized. The following table summarizes the final fair value of assets acquired and liabilities assumed as of the date of acquisition:


(in thousands)	Estimated Fair Value
Assets acquired:
Cash and cash equivalents	$	8,065
Accounts receivable, other(1)		2,758
Prepaid expenses and other current assets		459
Property, plant and equipment, net		16,711
Intangibles(2)		215,000
Deferred tax assets		18,112
Other long-term assets		1,424
Total identifiable assets acquired	$	262,529
Liabilities assumed:
Accounts payable	$	(1,964	)
Accrued expenses and other current liabilities		(754	)
Deferred tax liabilities		(55,718	)
Other long-term liabilities		(848	)
Total liabilities assumed		(59,284	)
Net assets acquired	$	203,245
Purchase consideration	$	319,466
Goodwill(3)	$	116,221

(1)

The value approximates the gross contractual amount of accounts receivables. The contractual amount not expected to be collected is immaterial.

(2)

Intangible assets acquired consisted of in-process research and development (“IPR&D”). The estimated fair values of the IPR&D assets were determined based on the present values of the expected cash flows to be generated by the respective underlying assets. The

Acquisition-related costs are not included as a component of consideration transferred but are expensed in the periods in which costs are incurred. The Company did not incur any acquisition- and integration -related costs during the three months ended June 30, 2026. For the six months ended June 30, 2026, the Company incurred $1.9 million of acquisition- and integration-related costs, including legal, accounting, compensation arrangements and other related fees. The Company incurred $14.7 million and $17.2 million of acquisition- and integration-related costs in the three and six months ended June 30, 2025, respectively. These costs were recorded in operating expenses in the condensed consolidated statements of operations in the period in which they were incurred.

On July 21, 2025, Lantheus Radiopharm UK acquired the entire issued share capital of Lantheus Biosciences pursuant to the LMI Purchase Agreement with Life Medical, Life Healthcare Group Holdings Limited and Lantheus Medical as Lantheus Radiopharm UK’s guarantor (such acquisition, the “LMI Acquisition”). Lantheus Biosciences possesses an Alzheimer’s disease radiodiagnostic commercial infrastructure, R&D capabilities, and an established international footprint. The LMI Acquisition includes Neuraceq, an Alzheimer’s disease radiodiagnostic. Neuraceq is commercially approved in the United States, Canada, the European Union, the United Kingdom, Switzerland, China, Japan, South Korea, and Taiwan. As consideration for the LMI Acquisition, the Company remitted an upfront payment of $355.2 million in cash to Life Medical. In November 2025 and in accordance with the terms of the LMI Purchase Agreement, the Company finalized the net working capital accounts with Life Medical and received a $2.3 million payment from Life Medical. The Company received an additional $0.3 million working capital settlement from Life Medical in April 2026. The total $2.6 million payments were recorded as adjustments to purchase consideration since the date of acquisition.

In connection with the LMI Acquisition, the Company could be required to pay up to an additional $400.0 million in potential earn-out and milestone payments as a percentage of and upon achievement of specified net sales thresholds, respectively, of Neuraceq and other pipeline assets. Additionally, the Company assumed a contingent consideration liability owed to Piramal (see Note 4, “Fair Value of Financial Instruments”), which is excluded from purchase consideration.

The potential remaining earn-out and milestone payments are accounted for as contingent consideration, the fair value of which is determined using a Monte Carlo simulation in a risk-neutral framework. The fair value of the total contingent consideration is included in accrued expenses and other current liabilities, long-term contingent consideration liabilities, net of current portion and other long-term liabilities in the Company’s condensed consolidated balance sheets at June 30, 2026.

The acquisition date fair value of the provisional consideration transferred in the LMI Acquisition consisted of the following:


(in thousands)	Preliminary Estimate		Measurement Period Adjustment			Final
Cash consideration	$	355,204	$	(2,590	)	$	352,614
Fair value of contingent consideration		27,000		—			27,000
Total purchase consideration	$	382,204	$	(2,590	)	$	379,614

The LMI Acquisition was accounted for as an acquisition of a business under ASC 805, which requires that assets acquired and liabilities assumed be recognized at their fair values as of the acquisition date. While the Company uses its best estimates and assumptions as part of the purchase price allocation process to value the assets acquired and liabilities assumed, its estimates and assumptions are subject to change during the measurement period, which is up to one year from the date of acquisition. Fair value estimates are based on a complex series of judgments about future events and uncertainties and rely heavily on estimates and assumptions. The judgments used to determine the estimated fair value assigned to each class of assets acquired and liabilities assumed, as well as asset lives, can materially impact the Company’s condensed consolidated statements of operations.

As of June 30, 2026, the purchase accounting for the LMI Acquisition has not been finalized. As additional information becomes available, the Company may further revise its preliminary purchase price allocation during the remainder of the measurement period. Besides

tax implications of the purchase price allocation, the final allocation may result in additional changes to other assets and liabilities. The following table summarizes the fair values of assets acquired and liabilities assumed as of the date of acquisition:


(in thousands)	Estimated Fair Value
Assets acquired:
Cash and cash equivalents	$	46,193
Accounts receivable, other(1)		25,123
Inventory		1,125
Prepaid expenses and other current assets		1,974
Property, plant and equipment, net		4,979
Intangibles(2)		394,000
Deferred tax assets		15,993
Other long-term assets		11,506
Total identifiable assets acquired	$	500,893
Liabilities assumed:
Accounts payable	$	(5,715	)
Accrued expenses and other current liabilities		(25,964	)
Deferred tax liabilities		(72,570	)
Other long-term liabilities		(79,904	)
Total liabilities assumed		(184,153	)
Net assets acquired	$	316,740
Purchase consideration	$	379,614
Goodwill(3)	$	62,874

(1)

The value approximates the gross contractual amount of accounts receivables. The contractual amount not expected to be collected is immaterial.

(2)

Intangible assets acquired consisted of IPR&D and currently marketed products. The estimated fair values of the IPR&D and currently marketed product assets were determined based on the present values of the expected cash flows to be generated by the respective underlying assets. The Company used a discount rate of 23.5% and 23.0% for IPR&D and currently marketed products, respectively. IPR&D cash flows have been probability-adjusted to reflect the risks of technical and regulatory success of the products, which the Company believes are appropriate and representative of market participant assumptions. The Company estimates that the acquired currently marketed product asset has a useful life of 10.5 years.

(3)

The goodwill recognized is attributable to future technologies that are not separately identifiable that could potentially add to the currently developed and pipeline products and Lantheus Biosciences’s assembled workforce. Future technologies did not meet the criteria for recognition separately from goodwill because they are part of the future development and growth of the business. Goodwill of $62.9 million recognized in connection with the LMI Acquisition is not deductible for tax purposes.

Acquisition-related costs are not included as a component of consideration transferred but are expensed in the periods in which costs are incurred. The Company incurred $1.9 million and $3.8 million of acquisition and integration-related costs, including legal, accounting, compensation arrangements and other related fees in the three and six months ended June 30, 2026. The Company incurred $36.7 million of acquisition- and integration-related costs in 2025. These costs were recorded in operating expenses in the condensed consolidated statements of operations in the period in which they were incurred.

On January 8, 2024, the Company entered into an agreement with Perspective to participate in Perspective’s next qualified financing to purchase Perspective Shares. On January 22, 2024, the Company purchased 56,342,355 Perspective Shares, representing 11.39% of the outstanding Perspective Shares, at the fair market offering price of $0.37 per share. Included within the agreement is a covenant which allows for the Company to designate one observer to Perspective’s board of directors. The observer has the option to attend any or all board meetings in a nonvoting capacity and the right to receive any board materials, except under certain instances where attorney-client privilege is necessary, where the material relates to a business or contractual relationship with the Company, to avoid bona fide conflict of interest, exposure of trade secrets or relating to a change of control transaction. The Company purchased 60,431,039 Perspective Shares at a fair market purchase price of

$0.95 per share as an investor in a private placement transaction on March 6, 2024, which resulted in the Company holding a cumulative 19.90% of the outstanding Perspective Shares (or 17.35% on a fully diluted basis) after giving effect to the closing of the private placement transaction. The Company’s ownership has been further diluted since the original investment was made. The Company does not have the ability to exercise significant influence over operating and financial policies of Perspective based on its level of ownership of Perspective and because the Company’s board observer has no voting rights and there is otherwise no participation in policy-making processes, no interchange of managerial personnel, and no sharing of technology between the Company and Perspective. See Note 4, “Fair Value of Financial Instruments,” for more information on the Company’s investment in Perspective.

Also effective January 8, 2024, the Company obtained certain options and rights from Perspective for an aggregate upfront payment of $28.0 million in cash. The options and rights received from Perspective that remain open are as follows:

On June 15, 2024, the Company entered into an agreement with Radiopharm to acquire all of Radiopharm’s rights to two licensed preclinical assets for an upfront payment of $2.0 million. The Company acquired global exclusive rights to both a leucine-rich repeat-containing protein 15 (“LRRC15”)-targeted monoclonal antibody and to a Trophoblast cell surface antigen-2 (“TROP2”)-targeted radiodiagnostic. LRRC15, which is also known as LNTH-2403, is a potential first-in-class, highly specific monoclonal antibody radio-conjugate with both Orphan Drug and Rare Pediatric Disease designations from the U.S. Food and Drug Administration for the treatment of osteosarcoma. The agent is designed to target the surrounding tumor micro-environment cells expressing the protein potentially treating a broad range of cancers. The TROP2-targeted nanobody radio-conjugate, which is also known as LNTH-2404, is designed to target TROP2, an intracellular calcium signal transducer that is overexpressed in various types of adenocarcinomas with minimal expression in normal tissues and is associated with tumor aggressiveness, poor prognosis and drug resistance.

In connection with this acquisition, the Company assumed the underlying license agreements related to the two preclinical assets, together with their respective milestone and royalty payment obligations. The Company could pay up to an additional $20.0 million in milestone payments upon achievement of specified regulatory milestones. The Company could also pay up to an additional $6.5 million in sales milestone payments upon the achievement of specified annual commercial sales thresholds in the event the Company pursues commercialization, as well as royalty payments for commercial sales. Costs of IPR&D projects acquired as part of an asset acquisition that have no alternative future use are expensed when incurred.

During the third quarter of 2024, the Company purchased 149,625,180 Radiopharm Shares, for an aggregate purchase price of approximately $5.0 million. During 2025, the Company purchased an aggregate additional 388,333,333 Radiopharm Shares for an aggregate purchase price of approximately $10.0 million. The Company does not have the ability to exercise significant influence over operating and financial policies of Radiopharm based on its ownership and because there is no participation in policy-making processes, no interchange of managerial personnel, and no sharing of technology between the Company and Radiopharm. See Note 4, “Fair Value of Financial Instruments,” for more information on the Company’s investment in Radiopharm.

On July 3, 2024, the Company acquired from Lantheus Biosciences the global rights to RM2, a gastrin-releasing peptide receptor-targeting agent, including the associated novel, clinical-stage radiotherapeutic and radiodiagnostic pair, referred to as 177Lu-DOTA-RM2 and 68Ga-DOTA-RM2 (and which the Company now refers to as LNTH-2401 and LNTH-2402, respectively), for an upfront payment of $35.0 million plus a $1.0 million payment made prior to the acquisition (the “RM2 Asset Purchase”), pursuant to the Sublicense, Development and Collaboration Agreement, by and between the Company and Lantheus Biosciences, dated as of June 27, 2024 (the “RM2 Sublicense Agreement”). Pursuant to the RM2 Sublicense Agreement, the Company incurred €10.0 million in regulatory milestones in 2025, and agreed to pay up to an additional €127.5 million (reduced as discussed below) in regulatory and development milestone payments upon achievement of

clinical trial thresholds and approvals in different regions, up to €280.0 million in net sales milestones if products are commercialized and meet certain sales thresholds, and royalties on net sales of RM2.

Costs of IPR&D projects acquired as part of an asset acquisition that have no alternative future use are expensed when incurred, and therefore, charges of $11.2 million in 2025 and $36.0 million in 2024 were recognized in R&D expenses related to the RM2 Asset Purchase.