Note 1 - Organization, Plan of Business Operations	9 Months Ended
Sep. 30, 2023
Notes to Financial Statements
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]	Note 1 - Organization, Plan of Business Operations Avenue Therapeutics, Inc. (the “Company” or “Avenue”) was incorporated in Delaware on February 9, 2015, as a wholly-owned subsidiary of Fortress Biotech, Inc. (“Fortress”). Avenue is a specialty pharmaceutical company focused on the development and commercialization of therapies for the treatment of neurologic diseases. Avenue's current product candidates include AJ201 for the treatment of spinal and bulbar muscular atrophy ("SBMA", also known as Kennedy's Disease), intravenous tramadol ("IV tramadol") for the treatment of post-operative acute pain, and BAER-101 for the treatment of epilepsy and panic disorders. Reverse Stock Split As a result of the reverse stock split effective on September 23, 2022, every 15 shares of common stock outstanding immediately prior to the effectiveness of the reverse stock split were combined and converted into one share of common stock without any change in the par value per share. No fractional shares were issued in connection with the reverse stock split. In connection with the reverse stock split, the holders of a majority of the voting power of Avenue's capital stock executed a written consent approving the reduction of the number of authorized shares of common stock immediately after the reverse stock split from 50,000,000 to 20,000,000 shares, which reduction became effective on September 23, 2022. On February 2, 2023, following the approval of Avenue's Board of Directors and Avenue's stockholders at the Company’s 2022 annual meeting of stockholders, the Avenue filed an amendment to Avenue's Third Amended and Restated Certificate of Incorporation to increase the number of authorized shares of common stock from 20,000,000 to 75,000,000 shares. All share and per share information has been retroactively adjusted to give effect to the reverse stock split for all periods presented, unless otherwise indicated. Liquidity and Capital Resources Going Concern These consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles ("GAAP") assuming the Company will continue as a going concern. The going concern assumption contemplates the realization of assets and satisfaction of liabilities in the normal course of business. However, as described below, substantial doubt about the Company’s ability to continue as a going concern exists. The Company is not yet generating revenue, has incurred substantial operating losses since its inception and expects to continue to incur significant operating losses for the foreseeable future as it executes on its product development plan and may never become profitable. As of September 30, 2023, the Company had an accumulated deficit of $91.6 million. Due to uncertainties regarding future operations of the Company for a study protocol that could form the basis for the submission of a complete response to the second Complete Response Letter for IV tramadol, and the expansion of the Company’s development portfolio within neuroscience with the consummation of the transaction with Fortress for the acquisition of Baergic Bio, Inc. ("Baergic"), the Company will need to secure additional funds through equity or debt offerings, or other potential sources, the timing of which is unknown at this time. The Company will require additional funds to cover operational expenses over the next 12 months. The Company cannot be certain that additional funding will be available to it on acceptable terms, or at all. These factors individually and collectively cause substantial doubt about the Company’s ability to continue as a going concern to exist within one year from the date of the issuance of this report. The consolidated financial statements do not include any adjustments to the carrying amounts and classification of assets, liabilities, and reported expenses that may be necessary if the Company were unable to continue as a going concern.

Note 1 - Organization, Plan of Business Operations

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]

Note 1 - Organization, Plan of Business Operations

Avenue Therapeutics, Inc. (the “Company” or “Avenue”) was incorporated in Delaware on February 9, 2015, as a wholly-owned subsidiary of Fortress Biotech, Inc. (“Fortress”). Avenue is a specialty pharmaceutical company focused on the development and commercialization of therapies for the treatment of neurologic diseases. Avenue's current product candidates include AJ201 for the treatment of spinal and bulbar muscular atrophy ("SBMA", also known as Kennedy's Disease), intravenous tramadol ("IV tramadol") for the treatment of post-operative acute pain, and BAER-101 for the treatment of epilepsy and panic disorders.

Reverse Stock Split

As a result of the reverse stock split effective on September 23, 2022, every 15 shares of common stock outstanding immediately prior to the effectiveness of the reverse stock split were combined and converted into one share of common stock without any change in the par value per share. No fractional shares were issued in connection with the reverse stock split. In connection with the reverse stock split, the holders of a majority of the voting power of Avenue's capital stock executed a written consent approving the reduction of the number of authorized shares of common stock immediately after the reverse stock split from 50,000,000 to 20,000,000 shares, which reduction became effective on September 23, 2022. On February 2, 2023, following the approval of Avenue's Board of Directors and Avenue's stockholders at the Company’s 2022 annual meeting of stockholders, the Avenue filed an amendment to Avenue's Third Amended and Restated Certificate of Incorporation to increase the number of authorized shares of common stock from 20,000,000 to 75,000,000 shares. All share and per share information has been retroactively adjusted to give effect to the reverse stock split for all periods presented, unless otherwise indicated.

Liquidity and Capital Resources

Going Concern

These consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles ("GAAP") assuming the Company will continue as a going concern. The going concern assumption contemplates the realization of assets and satisfaction of liabilities in the normal course of business. However, as described below, substantial doubt about the Company’s ability to continue as a going concern exists.

The Company is not yet generating revenue, has incurred substantial operating losses since its inception and expects to continue to incur significant operating losses for the foreseeable future as it executes on its product development plan and may never become profitable. As of September 30, 2023, the Company had an accumulated deficit of $91.6 million. Due to uncertainties regarding future operations of the Company for a study protocol that could form the basis for the submission of a complete response to the second Complete Response Letter for IV tramadol, and the expansion of the Company’s development portfolio within neuroscience with the consummation of the transaction with Fortress for the acquisition of Baergic Bio, Inc. ("Baergic"), the Company will need to secure additional funds through equity or debt offerings, or other potential sources, the timing of which is unknown at this time. The Company will require additional funds to cover operational expenses over the next 12 months. The Company cannot be certain that additional funding will be available to it on acceptable terms, or at all. These factors individually and collectively cause substantial doubt about the Company’s ability to continue as a going concern to exist within one year from the date of the issuance of this report. The consolidated financial statements do not include any adjustments to the carrying amounts and classification of assets, liabilities, and reported expenses that may be necessary if the Company were unable to continue as a going concern.