Note 1 - Description of Business	12 Months Ended
Dec. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	1. 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.” Discontinued Operations 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.

Note 1 - Description of Business

12 Months Ended

Dec. 31, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

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.”

Discontinued Operations

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.