Perspective Therapeutics, Inc.

Description of Business

Perspective Therapeutics, Inc. is a radiopharmaceutical development company that is pioneering advanced treatment applications for cancers throughout the body. The accompanying consolidated financial statements are those of Perspective Therapeutics, Inc., and its wholly owned subsidiaries, referred to herein as “Perspective Therapeutics” or the “Company.”

On April 12, 2024, the Company completed the sale of its Cesium-131 brachytherapy business and substantially all of the assets of Isoray Medical, Inc. (Isoray), a wholly owned subsidiary of Perspective Therapeutics, to GT Medical Technologies, Inc., a Delaware corporation (GT Medical) (such transaction being the GT Medical Closing). Pursuant to the GT Medical Closing, GT Medical issued to Isoray 279,516 shares of GT Medical’s common stock, par value $0.0001 per share, representing 0.5% of GT Medical’s issued and outstanding capital stock on a fully diluted basis as of the closing. Accordingly, the financial information and operating results of the Cesium-131 brachytherapy business have been presented as discontinued operations in the consolidated financial statements for all periods presented. Unless otherwise noted, discussion within these notes to the consolidated financial statements relates to continuing operations. For additional information, see Note 4, Discontinued Operations, in this Annual Report on Form 10-K (Form 10-K).

Reverse Stock Split

On June 14, 2024, the Company effected a 1-for-10 reverse stock split (Reverse Split) of the Company’s issued and outstanding shares of common stock, par value $0.001 per share (Common Stock), and the Common Stock began trading on a split-adjusted basis on June 17, 2024. The Reverse Split did not reduce the total number of authorized shares of Common Stock or the Company’s preferred stock, par value $0.001 per share (Preferred Stock), or change the par values of the Common Stock or Preferred Stock. The Reverse Split affected all stockholders uniformly and did not affect any stockholder’s ownership percentage of the shares of Common Stock (except to the extent that the Reverse Split resulted in some of the stockholders receiving cash in lieu of fractional shares). All outstanding options and warrants entitling their holders to purchase shares of Common Stock were adjusted as a result of the Reverse Split, in accordance with the terms of each such security. In addition, the number of shares reserved for future issuance pursuant to the Company’s equity incentive plans was also adjusted accordingly. As a result, all historical per share data, number of shares issued and outstanding, and outstanding options and warrants for the periods presented in the accompanying consolidated financial statements and notes thereto have been adjusted retroactively in this Form 10-K, where applicable, to reflect the Reverse Split.

Segment Information

A segment is defined as a component of an entity that has discrete financial information available for regular evaluation by the Chief Operating Decision Maker (CODM) and is used to make decisions on how to allocate resources and assess performance. The Company has one operating and reportable segment, which is its radiopharmaceutical development segment. The accounting policies of the radiopharmaceutical development segment are the same as those reported in Note 2, Summary of Significant Accounting Policies. The measurement of segment profit or loss is reported as “net loss” in the Consolidated Statements of Operation and Comprehensive Loss. The Company monitors its cash, cash equivalents and short-term investments, as reported in the Consolidated Balance Sheets, to determine funding for its research and development. To allocate resources, the Company’s CODM, who is its Chief Executive Officer, regularly reviews scientific data from clinical and preclinical studies and forecasted expenses for continued operations. The Company currently does not generate revenue from commercial products and incurs the majority of its expenses in the United States.

Liquidity

The Company assesses its liquidity in terms of its ability to generate cash to fund its operating, investing and financing activities. The Company has had a history of operating losses and an absence of significant recurring cash inflows from revenue. At December 31, 2025, the Company had cash, cash equivalents and short-term investments of$144.7 million and total accumulated deficit of$334.8 million. In February 2026, the Company announced the closing of an underwritten offering with gross proceeds of $175.0 million before deducting underwriting discounts and commissions and other offering-related expenses. The Company has historically financed its operations primarily through selling equity.

The Company believes that its$144.7 million of cash, cash equivalents and short-term investments as of December 31, 2025, together with the net proceeds from the February 2026 offering, will be sufficient to fund its current clinical milestones and operational investments into late 2027, though it may raise additional capital through a combination of equity offerings, debt financings, collaborations, strategic alliances and marketing, distribution or licensing arrangements and/or government funding and grants.

The accompanying consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and satisfaction of liabilities in the ordinary course of business. The operating plan may change as a result of many factors currently unknown to management, and there can be no assurance that the current operating plan will be achieved in the timeframe anticipated by management or at all, and the Company may need to seek additional funds sooner than anticipated. The consolidated financial statements do not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from potential unknown factors.

Reclassifications

The Company made certain reclassifications to prior period amounts in the consolidated financial statements and accompanying notes to conform to the current period presentation. The reclassification of these items had no impact on net loss, financial position or cash flows in the current or prior periods. Specifically, loss on divestiture was included in other noncash expense, net, as reported in the Consolidated Statements of Cash Flows.

Summary of Significant Accounting Policies

Basis of Presentation and Principles of Consolidation

The accompanying consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (GAAP). The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All significant intercompany transactions and balances have been eliminated in consolidation.

Cash Equivalents

The Company considers currency on hand, demand deposits, time deposits, and all highly liquid investments with an original maturity of three months or less at the date of purchase to be cash and cash equivalents. Cash and cash equivalents are held in various financial institutions in the United States.

Short-Term Investments

Available-for-Sale Securities

The Company has available-for-sale securities with original maturities of more than three months from the date of purchase that are specifically identified to fund operations. The available-for-sale securities are classified as current assets even though the stated maturity date may be one year or beyond the current balance sheet date as this reflects management’s intention to use the proceeds from the sale of these investments to fund the Company’s operations as necessary. The available-for-sale securities are carried at fair value with unrealized gains and non-credit-related losses recorded in other comprehensive income (loss) and included as a separate component of stockholders’ equity. The cost of available-for-sale securities is adjusted for amortization of premiums or accretion of discounts to maturity, and such amortization or accretion, as well as dividend and interest income, are included in interest income in the Consolidated Statements of Operations and Comprehensive Loss. Realized gains and losses from the sale of available-for-sale securities will be determined on a specific identification basis and included in interest income on the Company’s Consolidated Statements of Operations and Comprehensive Loss. Available-for-sale securities that are sold during the reporting period will not be remeasured prior to sale, resulting in a net presentation of changes in fair value.

Held-to-Maturity Investments

From time to time, the Company has invested in U.S. Treasury Bills in which it had the intent and ability to hold until the date of maturity. As such, these investments were carried at amortized cost and classified as held to maturity. At December 31, 2025 and December 31, 2024, the Company had no held-to-maturity investments.

Allowance for Credit Losses

For available-for-sale securities in an unrealized loss position, pursuant to Accounting Standards Update (ASU) 2016-13, Financial Instruments - Credit Losses: Measurement of Credit Losses on Financial Instruments, the Company first assesses whether it intends to sell, or if it is more likely than not that it will be required to sell, the security before recovery of its amortized cost basis. If either of the criteria regarding the intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through earnings. For securities that do not meet the aforementioned criteria, the Company evaluates whether the decline in fair value has resulted from the credit losses or other factors. In making this assessment, the Company considers the extent to which fair value is less than amortized cost, any changes in interest rates, market conditions, changes to the underlying credit ratings and forecasted recovery, among other factors. If this assessment indicates a credit loss exists, the present value of cash flows expected to be collected from the security is compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized costs basis, a credit loss exists and an allowance for credit losses is recorded, limited by the amount that the fair value is less than the amortized cost basis. The credit-related portion of unrealized losses and any subsequent improvements are recorded in interest income through an allowance account. Any impairment that has not been recorded through an allowance for credit losses is recognized in comprehensive loss in the Consolidated Statements of Operations and Comprehensive Loss, as applicable.

The Company elected the practical expedient to exclude the applicable accrued interest receivables from both the fair value and amortized cost basis of available-for-sale securities. Accrued interest receivable is recorded in prepaid expenses and other current assets in the Consolidated Balance Sheets. Uncollectible accrued interest receivables associated with an impaired security are reversed against interest income upon identification of the impairment.

Property and Equipment

Property and equipment is capitalized and carried at cost less accumulated depreciation. Depreciation expense is recorded to operating expenses. Normal maintenance and repairs are charged to expense as incurred. When any assets are sold or otherwise disposed of, the cost and accumulated depreciation are reversed with any resulting gain or loss being recognized in the Consolidated Statements of Operations and Comprehensive Loss.

Depreciation is computed using the straight-line method over the following estimated useful lives (in years):

Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the asset.

Property and equipment that is acquired but not yet placed in service is recorded in the Consolidated Balance Sheets at cost, and no depreciation expense or accumulated depreciation is recognized until the property and equipment is placed in service.

Management periodically reviews the net carrying value of all its long-lived assets on an asset-by-asset basis. An impairment loss is recognized if the carrying amount of a defined asset group is not recoverable and exceeds its fair value.

Although management has made its best estimate of the factors that affect the carrying value based on current conditions, it is reasonably possible that changes could occur which could adversely affect management’s estimate of net cash flows expected to be generated from its assets that could result in an impairment adjustment.

Prepaid Expenses and Other Assets

Prepaid expenses and other assets, which include website development costs, trademarks, patents and licenses, are stated at cost, less accumulated amortization. For website development, costs incurred in the planning stage are expensed as incurred whereas costs associated with the application and infrastructure development, graphics development, and content development are capitalized. Amortization of website development costs is computed using the straight-line method over the estimated economic useful lives of the asset. Trademarks and patents include costs, primarily legal, incurred in obtaining them. Amortization of trademarks and patents is computed using the straight-line method over the estimated economic useful lives of the assets. Licenses include costs related to licenses pertaining to the use of technology or operational licenses. These licenses are recorded at stated cost, less accumulated amortization. Amortization of licenses is computed using the straight-line method over the estimated economic useful lives of the assets. The Company periodically reviews the carrying values of other assets and evaluates the recorded basis for any impairment. Any impairment is recognized when the expected future operating cash flows to be derived from the licenses are less than their carrying value.

Fair Value Measurement

When required to measure assets or liabilities at fair value, the Company uses a fair value hierarchy based on the level of independent, objective evidence surrounding the inputs used. The Company determines the level within the fair value hierarchy in which the fair value measurements in their entirety fall. The categorization within the fair value hierarchy is based upon the lowest level of input that is significant to the fair value measurement. Level 1 uses quoted prices in active markets for identical assets or liabilities, Level 2 uses significant other observable inputs, and Level 3 uses significant unobservable inputs. The amount of the total gains or losses for the period is included in earnings that are attributable to the change in unrealized gains or losses relating to those assets and liabilities still held at the reporting date. The Company has no financial assets or liabilities that are adjusted to fair value on a recurring basis.

Certain assets and liabilities, including net assets acquired in business combinations, are measured at fair value on a nonrecurring basis; that is, the assets or liabilities are not measured at fair value on an ongoing basis but are subject to fair value adjustments only in certain circumstances (for example, when there is evidence of impairment or an acquisition of a business). The Company’s investments, which include cash equivalents and short-term investments, are measured and recorded at fair value on a recurring basis. The carrying amounts of financial instruments, which include short-term investments, prepaid expenses and other current assets, accounts payable and accrued expenses, note payable and equity method investment are considered to be representative of their respective fair value because of the short-term nature of most of the investments and because the instruments could be exchanged in a current transaction between willing parties.

Comprehensive Loss

Comprehensive loss is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources, including unrealized gains and losses on investments and foreign currency gains and losses.

Share-Based Compensation

The Company measures and recognizes expense for all share-based payments at fair value. The Company uses the Black-Scholes option valuation model to estimate fair value for all stock options and stock warrants on the date of grant. For stock options that vest over time, the Company recognizes compensation cost on a straight-line basis over the requisite service period for the entire award. The Company recognizes forfeitures as they occur.

Research and Development Costs

Research and development costs, including salaries, research materials, administrative expenses and contractor fees, are charged to operations as incurred. The cost of equipment used in research and development activities which has alternative uses is capitalized as part of fixed assets and not treated as an expense in the period acquired. Depreciation of capitalized equipment used to perform research and development is classified as research and development expense in the year recognized.

Income Taxes

Income taxes are accounted for under the liability method in accordance with Accounting Standards Codification (ASC) 740, Income Taxes. Under this method, the Company provides deferred income taxes for temporary differences that will result in taxable or deductible amounts in future years based on the reporting of certain costs in different periods for financial statement and income tax purposes. This method also requires the recognition of future tax benefits such as net operating loss carry-forwards, to the extent that realization of such benefits is not subject to an allowance. A valuation allowance is recognized on deferred tax assets when it is more likely than not that some or all of these deferred tax assets will not be realized. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operations in the period that includes the enactment of the change. In the event that the Company is assessed penalties and/or interest, penalties will be charged to other operating expense and interest will be charged to interest expense in the period that they are assessed. The Company recognizes liabilities for uncertain tax positions based on a two-step process, whereby (1) it is determined whether it is more likely than not that the tax positions will be sustained based on the technical merits of the position and (2) for those tax positions that meet the “more likely than not” recognition threshold, the largest amount of tax benefit that is greater than 50% likely of being realized upon ultimate settlement with the related tax authority would be recognized.

Leases

The Company accounts for its leases under ASC 842, Leases. Under this guidance, arrangements meeting the definition of a lease are classified as operating or financing leases and are recorded in the Consolidated Balance Sheets as both a right-of-use asset and lease liability, calculated by discounting fixed lease payments over the lease term at the rate implicit in the lease or the Company’s incremental borrowing rate. Lease liabilities are increased by interest and reduced by payments each period, and the right-of-use asset is amortized over the lease term. For operating leases, interest on the lease liability and the amortization of the right-of-use asset result in straight-line rent expense over the lease term. Variable lease expenses are recorded when incurred.

In-Process Research and Development (IPR&D)

IPR&D assets represent the fair value of incomplete research and development (R&D) projects that had not reached technological feasibility as of the date of the acquisition. Initially, these assets are classified as IPR&D and are not subject to amortization. IPR&D assets that reach commercialization are amortized on a straight-line basis over their estimated useful life. Estimated useful lives are determined considering the period the assets are expected to contribute to future cash flows. Post-acquisition R&D expenses related to these projects are expensed as incurred.

The Company tests indefinite-lived intangibles for impairment at least annually in the fourth quarter by assessing qualitative factors to determine whether it is more likely than not that the fair value of the assets is below their carrying value. The Company will also test these assets more frequently whenever events or circumstances change that would more likely than not reduce the fair value below the carrying amount. Such events or changes in circumstance include significant deterioration in overall economic conditions, changes in the business climate or a decline in our market capitalization. To test indefinite-lived intangible assets for impairment, the Company may perform both a qualitative assessment and quantitative assessment. For the qualitative assessment, the Company considers operating results and scientific data from clinical and preclinical studies as well as circumstances impacting the operations or cash flows of the reporting unit or indefinite-lived intangible assets, including macroeconomic conditions and industry and market conditions. If a qualitative assessment indicates the fair value of the asset is more likely than not less than its carrying value, then a quantitative assessment is performed which is based on an income-based valuation approach for indefinite-lived intangible. If it is determined that an impairment exists, the Company recognizes an impairment loss for the amount by which the carrying amount of the reporting unit or indefinite-lived intangible asset exceeds its estimated fair value. Fair value estimates are based on assumptions believed to be reasonable at the time, but such assumptions are subject to inherent uncertainty, and actual results may differ materially from those estimates.

The Company performed its annual qualitative IPR&D impairment analyses as of October 31, 2025, and determined it will no longer pursue further development of a preclinical asset within its IPR&D portfolio. For additional information regarding the IPR&D annual qualitative analysis, see Note 9, Intangible Assets and Other Assets, Net.

Grant Revenue Recognition

The Company enters into contracts with governmental agencies for services. These contracts are analyzed in order to determine if they should be accounted for under a revenue recognition model pursuant to ASC 606, Revenue from Contracts with Customers, or a grant model pursuant to ASC 958, Not-for-Profit Entities. If accounted for pursuant to a grant model, the Company must determine if the grant is conditional or unconditional, and if any conditional barriers exist which must be overcome. If unconditional, the grant is recognized as revenue immediately, and if conditional, the grant is recognized as revenue as and when the barriers are overcome. The Company concluded that payments received under the current grants represent conditional, nonreciprocal contributions, as described in ASC 958, and that the grants are not within the scope of ASC 606, as the organizations providing the grants do not meet the definition of a customer. The significant barrier to the current conditional grants is that the expenses incurred must meet the qualifications as established by the respective governmental agencies, so that the grant revenue is recognized as the qualified expenses are incurred. Expenses for grants are tracked using a project code specific to the grant, and the employees also track hours worked by using the project code. Under ASC 958, grants related to income are presented as part of the consolidated statements of operations, either separately or under a general heading. Both methods are acceptable under ASC 958. The Company has elected to record grants related to income separately in the Consolidated Statements of Operations and Comprehensive Loss as “grant revenue.” The related expenses are recorded within R&D and general and administrative.

Loss per Share

Basic and diluted loss per share is calculated by dividing net loss by the weighted average number of shares of Common Stock outstanding and does not include the impact of any potentially dilutive common stock equivalents. In January 2024 and May 2024, the Company issued pre-funded warrants in connection with the Public Offering (as defined below) and the Registered Offering (as defined below), respectively (see Note 3, Investments and Agreements, in this Form 10-K). As the pre-funded warrants’ exercise price is nominal and there are no conditions that must be satisfied prior to their exercise, the pre-funded warrants are included in the calculation of the basic and diluted earnings per share as of December 31, 2025. At each of December 31, 2025 and 2024, the calculation of diluted weighted average shares did not include common stock warrants or options that were potentially convertible into Common Stock as those would be antidilutive due to the Company’s net loss position.

Securities not considered in the calculation of diluted loss per share, but that could be dilutive in the future, are as follows:

Equity Method Investment

Investments in companies for which the Company has the ability to exercise significant influence, but do not control, are accounted for under the equity method. Under the equity method of accounting, the Company’s share of the net earnings or losses of the investee are included in other income (expense) in the Consolidated Statements of Operations and Comprehensive Loss. At the end of each reporting period, the Company considers whether impairment indicators exist to evaluate whether an equity method investment is impaired and, if so, record an impairment loss. Investments are accounted for on a one-quarter lag. As changes in ownership percentage of the Company’s investments occur, the Company assesses whether it can exercise significant influence and account for under the equity method. If its ownership percentage of the company in which it has investment changes, the Company recognizes a gain or loss on the investment in the period of change. Included in the consolidated financial statements for the year ended December 31, 2025 isthe Company’s proportional share of losses, which was de minimis.

Use of Estimates

The preparation of consolidated financial statements in accordance with GAAP requires management of the Company to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes of the Company including, but not limited to, the allowance for doubtful accounts receivable; the estimated useful lives used in calculating depreciation and amortization on the Company’s property and equipment, patents, trademarks and other assets; equity method investment; and inputs to the Black-Scholes calculation used in determining the expense related to share-based compensation including volatility and estimated lives of options granted. Accordingly, actual results could differ from those estimates and affect the amounts reported in the consolidated financial statements.

The Company categorizes the assets and liabilities of a business component as discontinued operations once management commits to a plan to sell, the business segment is available for immediate sale, management has initiated a plan to sell at a price that is reasonable in relation to its fair value, management anticipates the sale will occur within one year, and it is unlikely that significant changes will be made to the plan to sell. In addition, the business component must be comprised of operations and cash flows that are clearly distinguished from the rest of the entity. The results of discontinued operations are aggregated and presented separately in the Consolidated Balance Sheets and Consolidated Statements of Operations and Comprehensive Loss.

Recently Adopted and Recently Issued Accounting Pronouncements

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740), which expands income tax disclosure requirements, including additional information pertaining to rate reconciliation, income taxes paid and other disclosures. This update is effective for annual periods beginning after December 15, 2024. The Company adopted ASU 2023-09 for the year ended December 31, 2025, and applied the new disclosure requirements prospectively to the current annual period. Prior period disclosures have not been adjusted to reflect the new disclosure requirements. Adoption of this ASU did not have a material impact on the financial statements and resulted only in expanded income tax disclosures. For additional information, see Note 14, Income Taxes.

Accounting Standards Updates to Become Effective in Future Periods

In July 2025, the FASB issued ASU 2025-05, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses for Accounts Receivable and Contract Assets, which allows all entities a practical expedient to assume that current conditions as of the balance sheet date do not change for the remaining life of the assets. This update is effective for fiscal years beginning after December 15, 2025, with early adoption permitted. Entities that elect the practical expedient should apply the guidance prospectively. The Company adopted ASU 2025-05 on January 1, 2026, and the adoption had no material impact on its consolidated financial statements.

In November 2024, the FASB issued ASU 2024-03, Income Statement-Reporting Comprehensive Income-Expense Disaggregation Disclosures, which requires companies to disclose disaggregated information about any relevant expense caption presented on the face of the income statement within continuing operations in the following required expense categories, as applicable: (1) purchases of inventory, (2) employee compensation, (3) depreciation, (4) intangible asset amortization and (5) depreciation, depletion and amortization recognized as part of oil- and gas-producing activities or other depletion expenses. This update will be effective beginning after December 15, 2026. The Company is currently evaluating the impact that adoption of ASU 2024-03 will have on its consolidated financial statements.

In December 2025, the FASB issued ASU 2025-11, Interim Reporting (Topic 270): Narrow-Scope Improvements, which clarifies interim disclosure requirements and the applicability of Topic 270. This update will be effective beginning after December 15, 2027. The Company is currently evaluating the impact that adoption of ASU 2025-11 will have on its consolidated financial statements.

Also in December 2025, the FASB issued ASU 2025-10, Government Grants (Topic 832): Accounting for Government Grants Received by Business Entities, which establishes authoritative guidance on the recognition, measurement, presentation and disclosure of government grants received by business entities. This update will be effective beginning after December 15, 2028, and interim reporting periods within those annual reporting periods. The Company is currently evaluating the impact that adoption of ASU 2025-10 will have on its consolidated financial statements.

Significant Accounting Policies Related to Discontinued Operations

Accounts Receivable

Accounts receivable relate to the Company’s discontinued operations (see Note 4, Discontinued Operations) and are stated at the amount that management of the Company expects to collect from outstanding balances. Management provides for probable uncollectible amounts through an allowance for doubtful accounts. Additions to the allowance for doubtful accounts are based on management’s judgment, considering historical experience with write-offs, collections and current credit conditions. Balances which remain outstanding after management has used reasonable collection efforts are written off through a charge to the allowance for doubtful accounts and a credit to the applicable accounts receivable. Payments received subsequent to the time that an account is written off are treated as bad debt recoveries.

Revenue Recognition

The Company recognizes revenue based on the five-step model for revenue recognition as prescribed by ASU 2014-09, Revenue from Contracts with Customers (Topic 606), as follows: (1) identify the contract with the customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the prices to the performance obligations; and (5) recognize revenue. The Company has some agreements that contain general commercial terms and product prices but do not contain an obligation to provide goods to the customer. The Company’s performance obligation, which is established when the customer submits a purchase order and the Company accepts the order, is to deliver the product based on the purchase order received. The Company typically recognizes revenue at the time of shipment, at which time the title passes to the customer, and there are no further performance obligations.

Asset Retirement Obligation

The estimated fair value of the future retirement costs of the Company’s leased assets and the costs for the decontamination and reclamation of equipment located within the leased assets are recorded as a liability on a discounted basis when a contractual obligation exists; an equivalent amount is capitalized to property and equipment. The initial recorded obligation is discounted using the Company’s credit-adjusted risk-free rate and is reviewed periodically for changes in the estimated future costs underlying the obligation. The Company amortizes the initial amount capitalized to property and equipment and recognizes accretion expense in connection with the discounted liability over the estimated remaining useful life of the leased assets. Adjustments and changes to either the timing or amount of the original present value estimate underlying the obligation are made in the period incurred.

Investments and Agreements

On February 2, 2026, the Company entered into an underwriting agreement with Piper Sandler & Co. and UBS Securities LLC, as representatives of the underwriters named therein, in connection with its previously announced underwritten offering (2026 Offering) of 39,576,088 shares (2026 Offering Shares) of the Company’s Common Stock, and, in lieu of 2026 Offering Shares to certain investors, pre-funded warrants (2026 Pre-funded Warrants) to purchase 6,598,046 shares of Common Stock. The price to the investors for the 2026 Offering Shares was $3.79 per 2026 Offering Share, and the price to the investors for the 2026 Pre-funded Warrants was $3.789 per 2026 Pre-funded Warrant, which represents the per share price for the 2026 Offering Shares less the $0.001 per share exercise price for each such 2026 Pre-funded Warrant. The 2026 Offering closed on February 3, 2026.

The gross proceeds to the Company from the 2026 Offering were approximately $175.0 million, before underwriting discounts and commissions and other offering-related expenses.

The exercise price and the number of shares of Common Stock issuable upon exercise of each 2026 Pre-funded Warrant are subject to appropriate adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting the Common Stock as well as upon any distribution of assets, including cash, stock or other property, to the Company’s stockholders. The 2026 Pre-funded Warrants will not expire and are exercisable in cash or by means of a cashless exercise. A holder of the 2026 Pre-funded Warrants may not exercise such 2026 Pre-funded Warrants if the aggregate number of shares of Common Stock beneficially owned by such holder, together with its affiliates, would be more than 4.99% or 9.99%, as elected by such holder, of the issued and outstanding shares of Common Stock following such exercise, as such percentage ownership is determined in accordance with the terms of the 2026 Pre-funded Warrants. A holder of the 2026 Pre-funded Warrants may increase or decrease this percentage not in excess of 19.99% by providing at least 61 days’ prior notice to the Company.

The 2026 Offering was made pursuant to our shelf registration statement on Form S-3 (File No. 333-279692), as amended, which was most recently declared effective on April 8, 2025, a related base prospectus dated April 8, 2025, and a free writing prospectus and prospectus supplement each dated February 2, 2026.

On August 13, 2024, the Company entered into a Controlled Equity Offering SM Sales Agreement (2024 ATM Agreement) with Cantor Fitzgerald & Co. and RBC Capital Markets, LLC (each, an ATM Agent, and together, the ATM Agents) pursuant to which the Company from time to time may offer and sell shares (2024 ATM Shares) of its Common Stock, through or to the ATM Agents having an aggregate sales price of up to $250.0 million.

Subject to the terms and conditions of the 2024 ATM Agreement, each ATM Agent is required to use its commercially reasonable efforts to sell the ATM Shares from time to time, based upon the Company’s instructions. The Company has provided the ATM Agents with customary indemnification rights, and the ATM Agents will be entitled to a commission of up to 3.0% of the gross proceeds from each sale of the ATM Shares effectuated through or to the applicable ATM Agent selling the ATM Shares.

Sales of the 2024 ATM Shares under the 2024 ATM Agreement may be made in transactions that are deemed to be “at the market offerings” as defined in Rule 415 under the Securities Act of 1933, as amended. The Company has no obligation to sell any of the 2024 ATM Shares and may at any time suspend offers under the 2024 ATM Agreement or terminate the 2024 ATM Agreement.

Any Common Stock sold under the 2024 ATM Agreement will be issued and sold pursuant to the Company’s shelf registration statement on Form S-3 (File No. 333-279692) (the May 2024 Registration Statement), which initially became effective on May 24, 2024, and which was subsequently amended on March 26, 2025 and April 4, 2025, with Post-Effective Amendment #3 being declared effective by the SEC on April 8, 2025. On August 13, 2024, the Company initially filed a prospectus supplement to the May 2024 Registration Statement with the SEC in connection with the offer and sale of up to $250.0 million of the 2024 ATM Shares pursuant to the 2024 ATM Agreement. The Company re-filed the ATM prospectus supplement with each of the post-effective amendments to the May 2024 Registration Statement.

On February 18, 2025, the Company sold 3,379,377 shares of its Common Stock under the 2024 ATM Agreement at an average price of approximately $3.02 per common share, resulting in gross proceeds of approximately $10.2 million.

On May 24, 2024, the Company entered into an underwriting agreement with BofA Securities, Inc., as representative of the underwriters named therein, in connection with its previously announced underwritten offering (Registered Offering) of 5,151,588 shares (Registered Offering Shares) of Common Stock and, in lieu of Registered Offering Shares to certain investors, pre-funded warrants (May 2024 Pre-funded Warrants) to purchase 146,425 shares of Common Stock. The price to the investors for the Registered Offering Shares was $15.10 per Registered Offering Share, and the price to the investors for the May 2024 Pre-funded Warrants was $15.09 per May 2024 Pre-funded Warrant, which represents the per share price for the Registered Offering Shares less the $0.01 per share exercise price for each such May 2024 Pre-funded Warrant. The Registered Offering closed on May 29, 2024. BofA Securities, Inc., Oppenheimer & Co. Inc. and RBC Capital Markets, LLC acted as joint book-running managers for the Registered Offering and B. Riley Securities, Inc. acted as a co-manager for the Registered Offering. JonesTrading Institutional Services LLC acted as a financial advisor for the Registered Offering.

The gross proceeds to the Company from the Registered Offering were approximately $80.0 million, before underwriting discounts and commissions and other offering-related expenses.

The May 2024 Pre-funded Warrants became exercisable subsequent to the filing and effectiveness of an amendment to the Company’s Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware on June 14, 2024. The exercise price and the number of shares of Common Stock issuable upon exercise of each May 2024 Pre-funded Warrant were subject to appropriate adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting the Common Stock as well as upon any distribution of assets, including cash, stock or other property, to the Company’s stockholders. The May 2024 Pre-funded Warrants did not have an expiration date and were exercisable in cash or by means of a cashless exercise. A holder of the May 2024 Pre-funded Warrants could not exercise such May 2024 Pre-funded Warrants if the aggregate number of shares of Common Stock beneficially owned by such holder, together with its affiliates, would have been more than 4.99% or 9.99%, as elected by such holder, of the issued and outstanding shares of Common Stock following such exercise, as such percentage ownership is determined in accordance with the terms of the May 2024 Pre-funded Warrants. A holder of the May 2024 Pre-funded Warrants could increase or decrease this percentage not in excess of 19.99% by providing at least 61 days’ prior notice to the Company. The holders of the May 2024 Pre-funded Warrants exercised all of such warrants during the second quarter of 2025 by means of the cashless exercise provision and within the other constraints noted above.

On March 4, 2024, the Company entered into an investment agreement (March 2024 Investment Agreement) with certain accredited institutional investors (Institutional Investors) pursuant to which the Company agreed to issue and sell, in a private placement (the March 2024 Private Placement),9,200,998 shares of Common Stock, for a purchase price of $9.50 per share, representing the closing price of the Common Stock on March 1, 2024. The closing of the March 2024 Private Placement occurred on March 6, 2024.

The gross proceeds to the Company from the March 2024 Private Placement were approximately $87.4 million, before deducting fees payable to the Placement Agents (as defined below) and other estimated transaction expenses.

The March 2024 Private Placement was conducted pursuant to a Placement Agency Agreement, dated March 4, 2024 (the Placement Agency Agreement), by and between the Company and Oppenheimer & Co. Inc., as representative of the placement agents named therein (the Placement Agents). Per the Placement Agency Agreement, the Company agreed to: (i) pay the Placement Agents a cash fee equal to 5.85% of the gross proceeds received by the Company from the sale of the shares; and (ii) reimburse the Placement Agents for certain fees and expenses.

Lantheus Agreements

Investment Agreement

On January 8, 2024, the Company entered into an investment agreement (Lantheus Investment Agreement) with Lantheus Alpha Therapy, LLC, a Delaware limited liability company and wholly owned subsidiary of Lantheus Holdings, Inc. (Lantheus), pursuant to which the Company agreed to sell and issue to Lantheus in a private placement transaction certain shares (Lantheus Shares) of Common Stock. The closing of the purchase and sale of the Lantheus Shares to Lantheus by the Company (Lantheus Closing) was subject to the Company raising at least $50.0 million of gross proceeds (excluding Lantheus’ investment) in a qualifying third-party financing transaction, which occurred on January 22, 2024.

The number of Lantheus Shares sold was 5,634,235, representing 19.99% of the outstanding shares of Common Stock as of January 8, 2024. Pursuant to the Lantheus Investment Agreement, the Company agreed to cooperate in good faith to negotiate and enter into a registration rights agreement with Lantheus, obligating the Company to file a registration statement on Form S-3 with the SEC to register for resale the Lantheus Shares issued at the Lantheus Closing. The Company filed such Form S-3 on March 29, 2024, and the SEC declared it effective on April 9, 2024 (File No. 333-278362).

The Lantheus Investment Agreement also contains agreements of the Company and Lantheus whereby Lantheus is provided certain board observer and information rights of the Company, subject to certain exceptions.

The Lantheus Investment Agreement also provides Lantheus with certain pro rata participation rights to maintain its ownership position in the Company in the event that the Company makes any public or non-public offering of any equity or voting interests in the Company or any securities that are convertible or exchangeable into (or exercisable for) equity or voting interests in the Company, subject to certain exceptions.

Pursuant to the Lantheus Investment Agreement, the Company is required to notify Lantheus within 10 business days of the end of a fiscal quarter in which the Company issued shares of Common Stock pursuant to at-the-market programs, including the 2024 ATM Agreement, of (i) the number of shares of Common Stock issued during such fiscal quarter pursuant to the 2024 ATM Agreement and (ii) the average price per share received by the Company before commissions (ATM Average Price). Upon receipt of such notice, Lantheus may elect, at its option, to purchase all or a portion of its Pro Rata Portion (as defined in the Lantheus Investment Agreement) of such shares at an aggregate price equal to the number of shares purchased multiplied by the ATM Average Price for such quarter (ATM Participation Right). Pursuant to the Lantheus Investment Agreement, Lantheus may not exercise the ATM Participation Right more than two times per calendar year.

Asset Purchase Agreement

On January 8, 2024, the Company entered into an Asset Purchase Agreement (Progenics APA) with Progenics Pharmaceuticals, Inc., a Delaware corporation (Progenics) and affiliate of Lantheus, pursuant to which the Company acquired certain assets and the associated lease of Progenics’ radiopharmaceutical manufacturing facility in Somerset, NJ, for a purchase price of $8.0 million in cash. The transactions contemplated by the Progenics APA closed on March 1, 2024.

Option Agreement

On January 8, 2024, the Company entered into an option agreement (Option Agreement) with Lantheus whereby Lantheus was granted an exclusive option to negotiate an exclusive, worldwide, royalty- and milestone-bearing right and license to [212 Pb]VMT-α-NET, the Company’s clinical-stage alpha therapy developed for the treatment of neuroendocrine tumors. If good-faith negotiations fail, Lantheus has a one-year right to reenter negotiations if a third party offers to purchase or license the [212 Pb]VMT-α-NET program. Additionally, Lantheus has a right to co-fund the Investigational New Drug (IND) application, enabling studies for early-stage therapeutic candidates targeting prostate-specific membrane antigen and gastrin-releasing peptide receptor and, prior to IND filing, a right to negotiate for an exclusive license to such candidates. In consideration of the rights granted by the Company to Lantheus pursuant to the Option Agreement, Lantheus paid to the Company a one-time payment of $28.0 million, subject to certain withholding provisions associated with the closing of the Progenics APA.

Under the terms of the Option Agreement, Lantheus also had a right of first offer and last look protections for any third-party merger and acquisition transactions involving the Company for a 12-month period, which expired on January 8, 2025.

The Company determined that the Option Agreement should be accounted for as a research and development arrangement in accordance with ASC 730-20, Research and Development Arrangements, as Lantheus held approximately 19.9% of the Company’s outstanding Common Stock at March 31, 2024. The Option Agreement containsno repayment provisions, does not create any obligation to enter into any license, transfer or sale agreements with Lantheus, and does not restrict the use of the funds in any way.

Accordingly, the Consolidated Balance Sheets report current and long-term liabilities related to these options under the caption, “Deferred Income.” The values for each distinct option within the Option Agreement were determined by estimating the fair value of each distinct option by a third-party valuation firm and the liabilities will be recognized as income in the Consolidated Statements of Operations and Comprehensive Loss as the various options expire. In connection with the January 8, 2025 expiration of the right of first offer and last look provisions provided under the Option Agreement, the Company recognized $1.4 million in the Consolidated Statements of Operations and Comprehensive Loss as “Other income from a related party.”

On January 17, 2024, the Company entered into an underwriting agreement (Underwriting Agreement) with Oppenheimer & Co. Inc., as representative of the underwriters named therein (Underwriters), in connection with its previously announced underwritten public offering (Public Offering) of 13,207,521 shares (Public Shares) of Common Stock and, in lieu of Public Shares to certain investors, pre-funded warrants (Jan. 2024 Pre-funded Warrants) to purchase 3,008,694 shares of Common Stock. The price to the public for the Public Shares was $3.70 per Public Share, and the price to the public for the Jan. 2024 Pre-funded Warrants was $3.69 per Jan. 2024 Pre-funded Warrant, which represents the per share price for the Public Shares less the $0.01 per share exercise price for each such Jan. 2024 Pre-funded Warrant. Under the terms of the Underwriting Agreement, the Company granted the Underwriters an option, exercisable for 30 days, to purchase up to an additional 2,432,432 shares of Common Stock at the same price per share as the Public Shares, which was fully exercised by the Underwriters on January 18, 2024. The Public Offering closed on January 22, 2024.

The gross proceeds to the Company from the Public Offering were approximately $69.0 million, before underwriting discounts and commissions and other offering-related expenses.

The Public Offering was made pursuant to the Company’s shelf registration statement on Form S-3 (File No. 333-275638), declared effective by the SEC on December 14, 2023, a base prospectus dated December 14, 2023, and the related prospectus supplement dated January 17, 2024.

The Jan. 2024 Pre-funded Warrants were exercisable at any time after the date of issuance. The exercise price and the number of shares of Common Stock issuable upon exercise of each Jan. 2024 Pre-funded Warrant were subject to appropriate adjustment in the event of certain stock dividends and distributions, stock splits, stock combinations, reclassifications or similar events affecting the Common Stock as well as upon any distribution of assets, including cash, stock or other property, to the Company’s stockholders. The Jan. 2024 Pre-funded Warrants did not have an expiration date and were exercisable in cash or by means of a cashless exercise. A holder of Jan. 2024 Pre-funded Warrants could not exercise such Jan. 2024 Pre-funded Warrants if the aggregate number of shares of Common Stock beneficially owned by such holder, together with its affiliates, would have been more than 4.99% of the issued and outstanding shares of Common Stock following such exercise, as such percentage ownership is determined in accordance with the terms of the Jan. 2024 Pre-funded Warrants. A holder of Jan. 2024 Pre-funded Warrants could increase or decrease this percentage not in excess of 19.99% by providing at least 61 days’ prior notice to the Company. The holder of the Jan. 2024 Pre-funded Warrants exercised all such warrants during the fourth quarter of 2024 by means of the cashless exercise provision and within the other constraints noted above.

The Company entered into an ATM Issuance Sales Agreement, dated as of November 17, 2023, by and among the Company, Oppenheimer & Co. Inc., B. Riley Securities, Inc. and JonesTrading Institutional Services LLC, to create an ATM equity program under which it may offer and sell shares of its Common Stock, from time to time (2023 ATM Agreement).

On November 17, 2023, the Company filed a shelf registration statement on Form S-3 with the SEC (File No. 333-275638) and accompanying base prospectus, declared effective by the SEC on December 14, 2023, for the offer and sale of up to $200.0 million of its securities (December 2023 Registration Statement). Also on November 17, 2023, the Company filed a prospectus supplement with the SEC in connection with the offering of up to $50.0 million of shares of its Common Stock pursuant to the 2023 ATM Agreement under the December 2023 Registration Statement.

On April 11, 2024, the Company sold 3,535,246 shares of its Common Stock under the 2023 ATM Agreement at an average price of approximately $14.00 per common share, resulting in gross proceeds of approximately $49.5 million.

On May 25, 2024, the Company terminated the offering of securities pursuant to the December 2023 Registration Statement in connection with the filing and effectiveness of the May 2024 Registration Statement.

On August 7, 2024, the Company delivered written notice to Oppenheimer & Co., Inc., B. Riley Securities, Inc. and JonesTrading Institutional Services LLC that it was terminating the 2023 ATM Agreement, which termination became effective August 12, 2024.

The GT Medical Closing occurred on April 12, 2024 (GT Medical Closing Date). Previously, the Company announced that on December 7, 2023, Isoray entered into an Asset Purchase Agreement (GT Medical APA) by and among Isoray, the Company, and GT Medical pursuant to which Isoray would sell to GT Medical, and GT Medical would purchase from Isoray, all of Isoray’s right, title and interest in and to substantially all of the assets of Isoray related to Isoray’s commercial Cesium-131 business (the Business) including equipment, certain contracts, inventory and intellectual property. Subject to limited exceptions set forth in the GT Medical APA, GT Medical did not assume the liabilities of Isoray.

Pursuant to the terms of, and subject to the conditions specified in, the GT Medical APA, at the GT Medical Closing, (i) GT Medical issued to Isoray 279,516 shares of GT Medical’s common stock, par value $0.0001 per share, representing 0.5% of GT Medical’s issued and outstanding capital stock on a fully diluted basis as of the GT Medical Closing Date and (ii) Isoray has the right to receive, and GT Medical is obligated to pay, certain cash royalty payments during each of the first four years beginning upon the GT Medical Closing Date (each such year, a Measurement Period), as summarized below:

•

with respect to GT Medical’s net sales of Cesium-131 brachytherapy seeds for cases that do not utilize GT Medical’s GammaTile Therapy: (a) if such net sales for a Measurement Period are $10.0 million or less,3.0% of such net sales; (b) if such net sales for a Measurement Period are greater than $10.0 million and less than $15.0 million,4.0% of such net sales; and (c) if such net sales for a Measurement Period are $15.0 million or more,5.0% of such net sales; and

•

with respect to GT Medical’s net sales of GT Medical’s GammaTile Therapy utilizing Cesium-131 brachytherapy seeds:0.5% of such net sales for a Measurement Period.

In accordance with ASC 205-20, Presentation of Financial Statements – Discontinued Operations, the following table presents the components of discontinued operations in relation to the Business reported in the Consolidated Statements of Operations and Comprehensive Loss (in thousands):

The Company recognized a loss on classification as held for sale in December 2023 by identifying the assets and liabilities that were included in the GT Medical APA. Additionally, the loss recognized on classification as held for sale was determined using the estimated fair value of the GT Medical stock of $0.2 million received less the carrying value of the net assets sold. The fair value of the stock received was determined based on information provided to the Company by GT Medical from a current valuation study that was prepared for them. Excluded from the calculation of the loss are contingent royalties that could be received from future sales. As of March 31, 2025, the GT Medical stock was valued at $0.2 million based on an updated valuation report prepared for GT Medical.

During the second quarter of 2025, the Company recognized $0.2 million in royalties received pursuant to the GT Medical APA for the period from April 2024 to April 2025. In addition, during the second quarter of 2025, the Company reduced its reserve for environmental waste disposal by $0.3 million based on an estimate received from the hazardous waste disposal vendor.

There is $0.2 million of share-based compensation expense included in the Consolidated Statements of Cash Flows related to the discontinued operations for the year ended December 31, 2024.

For the years ended December 31, 2025 and 2024, there wasno provision (benefit) for income taxes recorded related to the discontinued operations. Additionally, the Company is in a loss position and has recorded a full valuation allowance for the deferred tax assets associated with the discontinued operations.

Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the following (in thousands):

Property and Equipment

In 2024, the Company purchased buildings in the metropolitan areas of Houston, TX, Chicago, IL, and Los Angeles, CA, which it intends to use for the manufacture of its product candidates upon completion of modifications and installation of equipment. Also in 2024, the Company entered into a Master Equipment and Services Agreement (MESA) and statements of work (SOWs) thereunder with Comecer SpA (Comecer), pursuant to which the Company agreed to purchase from Comecer manufacturing equipment for the production of the Company’s radiopharmaceutical products including, but not limited to, isotope processing hot cells and production suites and related equipment (collectively, the Deliverables) and services for installation and validation of the Deliverables at several of the Company’s production facilities in the United States. The aggregate consideration for such equipment and services pursuant to the MESA and SOWs is approximately €49.0 million payable in cash, excluding certain incidental costs such as taxes, customs and duties, local transport, insurance and rigging. The Company may also elect to purchase certain additional equipment and services pursuant to the SOWs. The MESA provides for the payment of certain amounts in installments over the course of the production, installation and validation of the Deliverables.

In October 2025, the Company entered into an agreement with a general contractor to begin building modifications at the Company’s facility in the Chicago, IL, metropolitan area along with preparations for the eventual installation of some of the Comecer manufacturing equipment and associated clean rooms. The Company currently estimates that the aggregate cost of these modifications will be approximately $27.5 million. However, actual costs may differ.

The Company’s property and equipment consisted of the following (in thousands):

Property and equipment not placed in service are items that meet the capitalization threshold, or which management believes will meet the threshold at the time of completion and which have yet to be placed into service as of the date of the balance sheets and, therefore, no depreciation expense has been recognized.

Available-for-Sale Securities

Available-for-sale securities consisted of U.S. Treasury Securities, U.S. Agency bonds, commercial paper, corporate debt securities and asset-backed securities.

The Company’s cash equivalents consisted of the following (in thousands):

The Company’s available-for-sale securities that are measured at fair value on a recurring basis consisted of the following (in thousands):

The Company’s available-for-sale securities are classified as current assets, even though the stated maturity date may be one year or more beyond the current balance sheet date, which reflects management’s intention to use the proceeds from sales of these securities to fund operations as needed. At December 31, 2025, there were 10 available-for-sale securities with a fair value of $6.0 million that were in a gross unrealized loss position for less than 12 months, andnone with that were in a gross unrealized loss position for 12 months or more. The Company determined it is not “more likely than not” that it will be required to sell these securities prior to recovery of their amortized cost basis. As such, the Company didnot record a credit allowance as of either December 31, 2025 or 2024. Accrued interest receivable on the Company’s available-for-sale securities was de minimis and $0.2 million as of December 31, 2025 and 2024, respectively. For the years ended December 31, 2025 and 2024, the Company didnot write off any accrued interest receivables, and there wereno realized gains or losses.

Fair Value Measurements

Fair value is defined as an exit price, representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. As a basis for considering such assumptions, the accounting guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows:

Level 1 - Observable inputs such as quoted prices in active markets;

Level 2 - Inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, quoted prices in markets with insufficient volume or infrequent transactions (less active markets), or model-driven valuations in which all significant inputs are observable or can be derived principally from, or corroborated with, observable market data; and

Level 3 - Unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

Below is the summary of our cash equivalents and short-term investments measured at fair value on a recurring basis and categorized using the fair value hierarchy (in thousands):

There wereno Level 3 financial instruments measured at fair value on a recurring basis as of December 31, 2025 and December 31, 2024.

For information related to the Company’s short-term investments, see Note 7, Available-for-Sale Securities.

Intangible Assets and Other Assets, Net

Intangible Assets

The Company’s IPR&D assets represent the estimated fair value of the pipeline of radiotherapy product candidates acquired from Viewpoint in February 2023. During the fourth quarter of 2025, as part of its annual qualitative analysis, the Company determined it will no longer pursue further development of an early-stage preclinical asset within its IPR&D portfolio. In connection with and as a result of this assessment, the Company recorded a $10.0 million noncash impairment loss for the three months ended December 31, 2025, which is recognized in “research and development” operating expenses in the Consolidated Statements of Operations and Comprehensive Loss. No IPR&D impairment loss was recorded in 2024.

The following table summarizes the components of the Company’s indefinite-lived intangible assets (in thousands):

For additional information related to IPR&D, see Note 2, Summary of Significant Accounting Policies.

As a result of a decline in the Company’s stock price and related market capitalization in November 2024 that continued into December 2024, the Company performed a quantitative impairment assessment of its goodwill. The goodwill was determined to be fully impaired as of December 31, 2024, and the Company recorded a goodwill impairment charge of $24.1 million for the year ended December 31, 2024. This impairment charge reduced the balance of goodwill to $0 at December 31, 2024.

Other Assets

Other assets, net of accumulated amortization consisted of the following (in thousands):

On August 23, 2022, the Company acquired 20% of the outstanding equity interests of RadRelease Pharmaceuticals LLC (RadRelease), an Indiana limited liability company, pursuant to a Membership Interest Purchase Agreement (MIPA), dated August 23, 2022, by and among RadRelease and the Company. Pursuant to the MIPA, the Company paid RadRelease approximately $0.2 million in cash consideration. The investment is recorded on a one-quarter lag. Included in the consolidated financial statements for the year ended December 31, 2025 is the Company’s proportional share of losses, which was de minimis.

Future amortization expense is expected to be as follows (in thousands):

Leases

The Company accounts for its leases under ASC 842, Leases. Effective April 1, 2024, the Company entered into a lease for lab space in Coralville, IA. The lease terminates in March 2028. Upon entering into this lease, the Company recognized a right-of-use asset and lease liability of approximately $1.1 million in the Consolidated Balance Sheet based upon the present value of the future lease payments discounted at an 8% discount rate using the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment as the lease does not provide an implicit discount rate. In November 2025, the Company entered into a lease agreement for office space, also in Coralville, IA, that terminates in November 2028. Upon entering into this lease, the Company recognized a right-of-use asset and lease liability of approximately $0.2 million in the Consolidated Balance Sheet based upon the present value of future lease payments discounted at an 8% discount rate using the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment as the lease does not provide an implicit discount rate.

The Company acquired a lease from Progenics, an affiliate of Lantheus, for a production facility in Somerset, NJ, effective on March 1, 2024 (see Note 3, Investments and Agreements, in this Form 10-K). The lease terminates on November 29, 2028. Upon entering into this lease, the Company recognized a right-of-use asset and lease liability of approximately $0.3 million in the Consolidated Balance Sheet based upon the present value of the future lease payments discounted at an 8% discount rate using the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment as the lease does not provide an implicit discount rate.

On August 8, 2024, the Company assumed a lease from Progenics for office space in Somerset, NJ (Office). The lease terminates on November 30, 2028. Upon entering into this lease, the Company recognized a right-of-use asset and lease liability of approximately $0.6 million in the Consolidated Balance Sheet based upon the present value of the future lease payments discounted at an 8% discount rate using the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment as the lease does not provide an implicit discount rate.

Upon assuming the lease, the Company entered into a license and access agreement with Lantheus, which provides access to both dedicated and shared space of the Office (Access Agreement). There isno renewal option, and the termination options are available only for material breaches. In consideration of the Access Agreement, Lantheus agreed to pay base rent and associated costs through December 2024 directly to the landlord. The base rent through December 2024 was less than $0.1 million (Prepaid Rent). Pursuant to ASC 842, Leases, the Access Agreement is a sublease in which the Company is a sublessor and Lantheus is a sublessee. The Company will amortize the Prepaid Rent over the entire lease term of 52 months.

On July 1, 2023, the Company entered into a lease for office space in Seattle, WA, that terminates in October 2028. Upon entering into this lease, the Company recognized a right-of-use asset and lease liability of approximately $0.8 million in the Consolidated Balance Sheet based upon the present value of the future lease payments discounted at an 8% discount rate using the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment as the lease does not provide an implicit discount rate.

The weighted average remaining term and discount rate for the Company’s operating leases as of December 31, 2025 was 2.6 years and 8%, respectively.

The Company’s operating lease expense was $1.1 million for theyear ended December 31, 2025 and $0.8 million for theyear ended December 31, 2024, and is recognized in “general and administrative” operating expenses in the Consolidated Statements of Operations and Comprehensive Loss.

The following table presents the future operating lease payments and lease liability included in the Consolidated Balance Sheet related to the Company’s operating leases as of December 31, 2025 (in thousands):

Asset Retirement Obligation

The Company had an asset retirement obligation (ARO) associated with the facility it leased in Richland, WA. This lease is included in the GT Medical APA and was assigned to GT Medical upon the GT Medical Closing, which occurred on April 12, 2024. As such, this liability is no longer reported as an ARO in the Company’s consolidated financial statements as of December 31, 2025 and 2024. However, the Company maintains the estimated liability in its consolidated financial statements related to hazardous waste removal. During the second quarter of 2025, the Company reduced this reserve by $0.3 million based on an estimate received from the hazardous waste disposal vendor. Accordingly, the estimated liability was $0.2 million and$0.5 million as of December 31, 2025 and 2024, respectively, and is included within “accounts payable and accrued expenses” in the Consolidated Balance Sheets. For additional information, see Note 4, Discontinued Operations, in this Form 10-K.

Note Payable

On December 29, 2022, Viewpoint obtained a promissory note in the amount of $1.7 million for the purpose of purchasing land and a building in Coralville, IA. The note bears interest at 6.15% per annum and is collateralized by the property. The note requires monthly principal and interest payments, and a balloon payment of approximately $1.5 million is due on December 29, 2027.

The following table presents the current and long-term portions of the note payable (in thousands):

The following table presents the future principal payments included in the Consolidated Balance Sheet related to the Company’s note payable as of December 31, 2025 (in thousands):

Share-Based Compensation

The Company currently provides share-based compensation under two equity incentive plans approved by the Board of Directors and the stockholders:

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2017 Equity Incentive Plan (2017 Incentive Plan) and

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2020 Third Amended and Restated 2020 Equity Incentive Plan (Amended and Restated Plan).

Options granted prior to fiscal 2017 were made pursuant to plans that have expired or were terminated.

The Company’s stockholders approved the 2017 Incentive Plan in June 2017. The 2017 Incentive Plan allows the Board of Directors to grant up to 4,000,000 shares of common stock to directors, officers, employees and consultants in a combination of equity incentive forms including incentive stock options (ISOs), non-qualified stock options (NQSOs), stock appreciation rights (SARs) or restricted shares of common stock.

On May 31, 2024, the Company held its 2024 Annual Meeting of Stockholders (Annual Meeting). At the Annual Meeting, the Company’s stockholders approved the Company’s Third Amended and Restated 2020 Equity Incentive Plan (the Amended and Restated Plan) which, among other things, (a) increased the aggregate number of shares of Common Stock authorized for issuance under the Amended and Restated Plan by 4,870,092 for a total of 12,500,000 shares of Common Stock, and (b) adjusted the “evergreen” provision included therein, such that the number of shares of Common Stock available for the grant of awards under the Amended and Restated Plan will automatically increase on January 1 of each year in an amount equal to 5% of the number of shares of Common Stock issued and outstanding on December 31 of the immediately preceding year (subject to adjustment in the event of stock splits and other similar events); provided, however, that the Company’s Board of Directors may act prior to January 1 of a given year to provide that there will be no increase in the share limit for such year or provide that the increase for such year will be a lesser number of shares of Common Stock. Under the Amended and Restated Plan, the Board of Directors may grant to directors, officers, employees and consultants various forms of equity, including ISOs, NQSOs, SARS, and restricted awards. On August 14, 2024, the Company filed a Form S-8 to register 4,870,092 additional shares of Common Stock authorized for issuance under the Amended and Restated Plan as approved by stockholders at the Annual Meeting. On January 1, 2026 and January 1, 2025, the number of shares of Common Stock available for grant increased by 3,716,899 and 3,533,573, respectively, pursuant to the “evergreen” provision in the Amended and Restated Plan. The Company filed a Form S-8 to register the January 1, 2025 additional shares on March 26, 2025.

The Black-Scholes option valuation model was developed for use in estimating the fair value of traded options which have no vesting restrictions and are fully transferable. In addition, option valuation models require the input of highly subjective assumptions, including the expected stock price volatility. The Company uses the Black-Scholes option valuation model because management believes the model is appropriate for the Company. However, management understands that because changes in the subjective input assumptions can materially affect the fair value estimate, this valuation model does not necessarily provide a reliable single measure of the fair value of its stock options. The weighted-average fair value is that of the grant dates of the awards. The risk-free interest rate is based on the U.S. Treasury security rate with an equivalent term in effect as of the date of grant. The expected term and expected volatility assumptions are based on historical data of the Company. The expected dividend yield ofzero reflects that the Company hasnot paid cash dividends and does not intend to pay cash dividends in the foreseeable future.

The weighted-average fair value of stock option awards granted and the key assumptions used in the Black-Scholes valuation model to calculate the fair value are as follows:

The following table presents the share-based compensation expense recognized for all share-based compensation arrangements, excluding share-based compensation expense reported in Note 4, Discontinued Operations (in thousands):

The total value of the stock options awards is expensed ratably over the vesting period applicable to the options. As of December 31, 2025, total unrecognized compensation cost related to stock-based options and awards was approximately $21.3 million, and the weighted-average period over which it is expected to be recognized is approximately 2.65 years.

The summary of stock option activity for the year ended December 31, 2025 is as follows:

All options granted had exercise prices equal to the closing price of the Company’s common stock on the grant date. The options were granted to employees, consultants and members of the Board of Directors and have a term of 10 years and generally vest over a four-year period.

The Company’s current policy is to issue new shares to satisfy option exercises.

Stockholders’ Equity

Preferred Stock

The Company’s Certificate of Incorporation authorizes the issuance of up to 7,000,000 shares of Preferred Stock with such rights and preferences, including liquidation, dividend, conversion and voting rights as determined by the Board. As of December 31, 2025, the Company has 5,000,000 designated Series B shares authorized of whichno shares are issued or outstanding.

Common Stock

The Company's Certificate of Incorporation authorizes the issuance of up to 750,000,000 shares of Common Stock, par value $0.001 per share. On June 14, 2024, the Company effected a Reverse Split of the Company’s issued and outstanding shares of Common Stock, and the Common Stock began trading on a split-adjusted basis on June 17, 2024. The Reverse Split did not reduce the total number of authorized shares of Common Stock or the Company’s Preferred Stock or change the par values of the Common Stock or Preferred Stock. For additional information regarding the Reverse Split, see Note 1, Description of Business.

As discussed in Note 3, Investments and Agreements, on February 2, 2026, the Company entered into an underwriting agreement with Piper Sandler & Co. and UBS Securities LLC, as representatives of the underwriters named therein, in connection with its 2026 Offering of 39,576,088 shares of the Company’s Common Stock, and, in lieu of 2026 Offering Shares to certain investors, 2026 Pre-funded Warrants to purchase 6,598,046 shares of Common Stock, resulting in gross proceeds of approximately $175.0 million.

On August 13, 2024, the Company entered into the 2024 ATM Agreement with Cantor Fitzgerald & Co. and RBC Capital Markets, LLC, pursuant to which the Company, from time to time, may offer and sell shares of its Common Stock. On February 18, 2025, the Company sold 3,379,377 shares of its Common Stock under the 2024 ATM Agreement at an average price of approximately $3.02 per common share, resulting in gross proceeds of approximately $10.2 million. For additional information regarding the 2024 ATM Agreement, see Note 3, Investments and Agreements.

During the year ended December 31, 2024, the Company entered into various agreements and raised approximately $306.7 million in gross proceeds. For additional information regarding these agreements, including the 2024 ATM Agreement, see Note 3, Investments and Agreements.

Warrants

The following table summarizes the activity of all common stock warrants and weighted-average exercise prices.

As of December 31, 2025, the Company had 184,197 common warrants outstanding and exercisable on or before November 24, 2027,89,804 common warrants outstanding and exercisable on or before December 18, 2027, and 64,714 common warrants outstanding and exercisable on or before December 31, 2027.

During the year ended December 31, 2024, the Company issued Pre-funded Warrants in connection with the January 2024 Public Offering and the May 2024 Registered Offering. In 2024, all of the Jan. 2024 Pre-funded Warrants were exercised on a cashless basis; therefore,7,703 of the Jan. 2024 Pre-funded Warrants were not issued and expired as part of the cashless exercise. During the second quarter of 2025, all of the May 2024 Pre-funded Warrants were exercised on a cashless basis; therefore,573 of the May 2024 Pre-funded Warrants were not issued and expired as part of the cashless exercise. For additional information related to these transactions, see Note 3, Investments and Agreements. The following table summarizes the activity of all Pre-funded Warrants, which automatically expire upon exercise, and weighted-average exercise prices.

Income Taxes

The components of loss before income taxes by U.S. and foreign jurisdictions are as follows (in thousands):

The expense (benefit) for income taxes for theyears ended December 31, 2025 and 2024 are as follows (in thousands):

As further described in Note 2, Summary of Significant Accounting Policies, the Company has elected to prospectively adopt the guidance in Topic 740. The following table is a reconciliation of the U.S. federal statutory rate to the Company’s effective rate for the year ended December 31,2025 in accordance with the guidance in ASU No. 2023-09 (in thousands):

1. State taxes in California made up the majority (greater than 50%) of this category.

The following table is a reconciliation of the U.S. federal statutory rate to the Company’s effective income tax for the year ended December 31, 2024 in accordance with the guidance prior to the adoption of ASU 2023-09 (in thousands):

Income taxes paid (net of refunds received) included the following (in thousands):

The significant components of the Company’s deferred tax assets and liabilities are as follows (in thousands):

The Company’s Australian subsidiary had an accumulated deficit at December 31, 2025, and, accordingly, no provision has been provided thereon for any unremitted earnings.

The future realization of the tax benefits from existing temporary differences, net operating loss carryforwards and other tax attributes ultimately depends on the existence of sufficient taxable income within the carryforward period. Therefore, at each balance sheet reporting date, the Company assesses the realizability of its deferred tax assets whether it is more likely than not that some portion or all its deferred tax assets will not be realized. In assessing the realizability of its deferred tax assets, the Company considers all available evidence, both positive and negative, including results of operations in recent years, projected future taxable income, expected reversal of existing deferred tax liabilities, and tax planning strategies in making its assessment. After considering all available evidence, the Company has determined that it is more likely than not that its net deferred tax assets will not be realized in the foreseeable future. Therefore, the Company continues to maintain a valuation allowance against its net deferred tax assets as of December 31, 2025.

The Company maintained a full valuation allowance against its U.S. net deferred tax assets as of December 31, 2025 and 2024 with the exception of deferred tax liabilities that are indefinite-lived and are not able to be used as a source of income. The valuation increased by $18.5 million and $11.9 million during theyears ended December 31, 2025 and 2024, respectively. The change in the valuation allowance for the year ended December 31, 2025 is primarily attributable to the capitalization of research and development costs. The change in the valuation allowance for the year ended December 31, 2024 is primarily attributable to net operating losses generated and the capitalization of research and development costs.

As of December 31, 2025, the Company has U.S. federal net operating loss carryforwards of $139.3 million which includes $89.6 million that have an unlimited carryforward period and $49.7 million that expire at various dates between 2026 and 2037. As of December 31, 2025, the Company has various state net operating loss carryforwards of $34.2 million that expire at various dates between 2033 and 2044.

As of December 31, 2025, the Company has U.S. federal research and development credits of $6.0 million that expire at various dates between 2035 and 2045, and state research and development credits of $0.1 million that begin to expire between 2036 and 2038.

The future realization of the Company’s net operating loss carryforwards and other tax attributes may be limited by the change in ownership rules under the U.S. Internal Revenue Code Section 382. Under Section 382, if a corporation undergoes an ownership change, the Company’s ability to utilize its net operating loss carryforwards and other tax attributes to offset income may be subject to an annual limitation. As of December 31, 2025, the Company has not completed a study to assess whether an ownership change has occurred or whether there have been multiple ownership changes.

A reconciliation of the beginning and ending balance of total unrecognized tax benefits is as follows (in thousands):

As of December 31, 2025 and 2024, the Company had gross unrecognized tax benefits of approximately $1.2 million and $0.5 million, respectively. The unrecognized tax benefits would give rise to additional deferred tax assets if recognized. This would also give rise to a corresponding increase in the valuation allowance and would not impact the Company’s effective tax rate. The Company didnot accrue interest or penalties related to unrecognized tax benefits as they relate to unutilized tax attributes.

The Company files income tax returns in the U.S., including various states, and jurisdictions outside the U.S. Therefore, the Company is subject to tax examination by various taxing authorities. The Company is not currently under examination and is not aware of any issues under review that could result in significant payments, accruals or material deviation from its tax positions. To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by local tax authorities to the extent such tax attribute is utilized in a future period. As of December 31, 2025, the tax years from 2021 to present remain open to examination by the various U.S. taxing authorities. However, to the extent the Company utilizes net operating losses from years prior to 2021, the statute remains open to the extent of the net operating losses or other credits that are utilized.

401(k) Plan

On January 1, 2024, the Company merged two prior 401(k) plans into a new 401(k) plan with a company match where 100% of the first 4% of participants’ contributions are matched, up to a maximum company match of 4% of eligible compensation (subject to IRS annual limits). For theyears ended December 31, 2025 and 2024, the Company recognized $0.9 million and $0.5 million in employer matching expense, respectively.

Commitments and Contingencies

The Company has been in settlement negotiations with a representative forsix stockholder plaintiff firms alleging the Company violated Delaware law in its preliminary proxy statement that was disseminated to stockholders in November 2022 for the Company’s annual meeting held in December 2022. Based on these settlement negotiations to date, the Company estimates that it will settle for no more than an aggregate of $0.2 million and, therefore, recorded an estimated liability of $0.2 million during the period ended December 31, 2022, which it maintained as of December 31, 2025. This balance is included in accrued expenses in the Consolidated Balance Sheets.

In May 2025, the Company entered into a supply agreement order with the U.S. Department of Energy (DOE) under which the Company will purchase Thorium-228 from the DOE during 2025 and 2026. The supply agreement includes a “take-or-pay” provision pursuant to which the Company is committed to purchasing approximately $8.4 million of Thorium-228 during the term of the agreement.

In October 2025, the Company entered into an agreement with a general contractor to begin building modifications at its facility in the Chicago, IL metropolitan area along with preparations for the eventual installation of some of the Comecer manufacturing equipment and associated clean rooms. The Company currently estimates that the aggregate cost of these modifications will be approximately $27.5 million. However, actual costs may differ.

In the ordinary course of business, the Company may agree to provide indemnification of varying scope and terms to vendors, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breaches of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with its officers and members of its Board of Directors that will require the Company to, among other things, indemnify those individuals against certain liabilities that may arise by reason of their status or service as officers or directors. The maximum amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnification obligations. The Company is not currently aware of any indemnification claims and has not accrued any liabilities related to such obligations in its consolidated financial statements as of December 31, 2025 or 2024.

Concentrations of Credit and Other Risks

The Company’s financial instruments that are exposed to concentrations of credit risk consist primarily of cash, cash equivalents, accounts receivable and short-term investments.

The Company routinely assesses the financial strength of its receivables and provides an allowance for doubtful accounts as necessary. At December 31, 2025 and 2024, the allowance was approximately$0.4 million and$0.5 million, respectively.

The Company currently obtains nearly all of its supply of Thorium-228 (a precursor to 212 Pb) from a single supplier, the DOE. The Company currently utilizes one vendor for the manufacture of resin chromatography columns that are used in its 212 Pb generators, and the Company relies on a single vendor to assemble and load isotopes into the generators that are used to extract 212 Pb for use in the doses for the Company’s clinical trials.

Related Parties

In connection with the Lantheus Investment Agreement entered into with Lantheus on January 8, 2024, the Company agreed to sell and issue the Lantheus Shares. The number of Lantheus Shares sold was 5,634,235, representing 19.99% of the outstanding shares of Common Stock as of January 8, 2024.

On January 8, 2024, the Company entered into the Progenics APA with Progenics, an affiliate of Lantheus, for a purchase price of $8.0 million. On March 1, 2024, the Company closed on the transactions contemplated by the Progenics APA.

Also on January 8, 2024, the Company entered into the Option Agreement with Lantheus whereby Lantheus was granted an exclusive option to negotiate an exclusive, worldwide, royalty- and milestone-bearing right and license to [212 Pb]VMT-α-NET, the Company’s clinical-stage alpha therapy developed for the treatment of neuroendocrine tumors. If good-faith negotiations fail, Lantheus has a one-year right to reenter negotiations if a third party offers to purchase or license the [212 Pb]VMT-α-NET program. Additionally, Lantheus has a right to co-fund the Investigational New Drug (IND) application, enabling studies for early-stage therapeutic candidates targeting prostate-specific membrane antigen and gastrin-releasing peptide receptor and, prior to IND filing, a right to negotiate for an exclusive license to such candidates. In consideration of the rights granted by the Company to Lantheus pursuant to the Option Agreement, Lantheus paid to the Company a one-time payment of $28.0 million, subject to certain withholding provisions associated with the closing of the Progenics APA.

Under the terms of the Option Agreement, Lantheus also had a right of first offer and last look protections for any third-party merger and acquisition transactions involving the Company for a 12-month period, which expired on January 8, 2025. In connection with the January 8, 2025 expiration of the right of first offer and last look provisions provided under the Option Agreement, the Company recognized $1.4 million on the Consolidated Statements of Operations and Comprehensive Loss as “Other income from a related party.”

On March 4, 2024, the Company entered into the March 2024 Investment Agreement in which the Company agreed to issue and sell 9,200,998 shares of Common Stock. Lantheus, a significant stockholder of the Company, purchased part of the shares issued to increase their ownership percentage to approximately 19.9% in the Company following the closing of the March 2024 Investment Agreement on March 6, 2024.

For additional information regarding the Lantheus Investment Agreement, the Progenics APA and the March 2024 Investment Agreement, see Note 3, Investments and Agreements.

On August 8, 2024, the Company entered into a license and access agreement with Lantheus. For additional information, see Note 10, Leases.