Note 1 - Nature of Business	9 Months Ended
Sep. 30, 2025
Notes to Financial Statements
Nature of Operations [Text Block]	1. Nature of Business The terms “MBI” or “the Company”, “we”, “our” and “us” are used herein to refer to Moleculin Biotech, Inc. MBI is a clinical-stage pharmaceutical company, organized as a Delaware corporation in July 2015. MBI is a late-stage pharmaceutical development company currently conducting a pivotal Phase 3 trial evaluating Annamycin, also known by its non-proprietary name "naxtarubicin", in combination with Cytarabine for the treatment of subjects with relapsed/refractory (R/R) acute myeloid leukemia (AML). The Company has two additional portfolios of technologies for hard-to-treat cancers and viruses with clinical and preclinical research funded by investigators at academic institutions. Each of its three core technologies is based substantially on discoveries made at and licensed from the University of Texas MD Anderson Cancer Center (MD Anderson) in Houston, Texas, and features one or more drugs that have successfully completed a Phase 1 clinical trial. Three of its six drug candidates have shown human activity in clinical trials and are currently or have been in Phase 1B/2 or Phase 2 clinical trials. Since MBI’s inception, its drugs have completed, are currently in, or have been permitted to proceed in, fourteen clinical trials. Annamycin, in a unique multilamellar lipid formulation, is the Company’s lead molecule, and MBI has recently concluded treatment in several Phase 1B/2 clinical trial for treating AML and has begun treating subjects in its Phase 3 clinical trial for the treatment of R/R AML. Annamycin was in two recently closed or concluded Phase 1B/2 clinical trials for treating Soft Tissue Sarcoma metastasized to the lungs (STS lung metastases, STS lung mets, or Advanced STS), with one physician-sponsored. The Company announced a physician-sponsored trial for Annamycin for the treatment of pancreatic cancer intended to begin in 2026. The one concluded trial has published its clinical study report. Additionally, there is another phase 1B/2 clinical trial that is physician sponsored which is investigating using WP1066 in combination with radiation for the treatment of glioblastoma, a form of brain cancer. The physician-sponsored trials utilize primarily external funds, such as grant funds, which are not presented in these financial statements. The Company does not have manufacturing facilities, and all manufacturing activities are contracted out to third parties. Additionally, the Company does not have a sales organization. The Company’s overall strategy is to seek potential out-licensing or outsourcing opportunities with development/commercialization strategic partners who are better suited for the marketing, sales and distribution of its drugs, if approved. In 2019, the Company sublicensed its technologies to Animal Life Sciences, Inc. (ALI), to enable research and commercialization for non-human use and share development data. As part of this agreement, ALI issued to the Company a 10% equity interest in ALI. On May 23, 2025, the Company received a letter from the Nasdaq Stock Market LLC (Nasdaq), which notified the Company that it does not presently comply with Nasdaq’s Listing Rule 5550(b)(1) (the “Equity Rule”), which requires that the Company maintain a minimum of $2.5 million in stockholders’ equity, and that the Company also does not meet the alternatives of market value of listed securities or net income from continuing operations set forth in the Equity Rule. The letter did not have any immediate effect on the listing of the Company’s common stock on the Nasdaq Capital Market, and the Company had 45 calendar days to submit a plan to regain compliance. The Company’s plan was accepted and the Staff granted an extension of up to 180 calendar days from May 23, 2025 through November 19, 2025 to evidence compliance. If the Company is not in compliance on that date, then the Company intends to submit an appeal to extend this date, however, there can be no assurance that such appeal would be successful. On June 27, 2025, the Company received another deficiency letter from the Staff of Nasdaq notifying the Company that for the last 30 consecutive business days the bid price for the Company’s common stock had closed below the minimum $1.00 per share requirement for continued inclusion on the Nasdaq Capital Market pursuant to Nasdaq Listing Rule 5550(a)(2) (the “Bid Price Rule”). The deficiency letter does not result in the immediate delisting of the Company’s common stock from the Nasdaq Capital Market. In accordance with Nasdaq Listing Rule 5810(c)(3)(A) (the “Compliance Period Rule”), the Company has been provided an initial period of 180 calendar days, or until December 24, 2025 (the “Compliance Date”), to regain compliance with the Bid Price Rule. If, at any time before the Compliance Date, the bid price for the Company’s common stock closes at $1.00 or more for a minimum of 10 consecutive business days as required under the Compliance Period Rule, the Staff is expected to provide written notification to the Company that it complies with the Bid Price Rule, unless the Staff exercises its discretion to extend this 10 day period pursuant to Nasdaq Listing Rule 5810(c)(3)(H). If the Company is not in compliance with the Bid Price Rule by December 24, 2025, the Company may be afforded a second 180 calendar day period to regain compliance. To qualify, the Company would be required to meet the continued listing requirement for market value of publicly held shares and all other initial listing standards for The Nasdaq Capital Market, except for the minimum bid price requirement. In addition, the Company would be required to notify Nasdaq of its intent to cure the minimum bid price deficiency, which may include, if necessary, implementing a reverse stock split. If the Company does not regain compliance with the Bid Price Rule by the Compliance Date and is not eligible for an additional compliance period at that time, the Staff will provide written notification to the Company that its common stock may be delisted. The Company would then be entitled to appeal the Staff’s determination to a NASDAQ Listing Qualifications Panel and request a hearing. There can be no assurance that, if the Company does appeal the delisting determination by the Staff to the NASDAQ Listing Qualifications Panel, that such appeal would be successful. The Company intends to monitor the closing bid price of its common stock and may, if appropriate, consider available options to regain compliance with the Bid Price Rule, which could include effecting a reverse stock split. However, there can be no assurance that the Company will be able to regain compliance with the Bid Price Rule.

Note 1 - Nature of Business

9 Months Ended

Sep. 30, 2025

1. Nature of Business

The terms “MBI” or “the Company”, “we”, “our” and “us” are used herein to refer to Moleculin Biotech, Inc. MBI is a clinical-stage pharmaceutical company, organized as a Delaware corporation in July 2015. MBI is a late-stage pharmaceutical development company currently conducting a pivotal Phase 3 trial evaluating Annamycin, also known by its non-proprietary name "naxtarubicin", in combination with Cytarabine for the treatment of subjects with relapsed/refractory (R/R) acute myeloid leukemia (AML). The Company has two additional portfolios of technologies for hard-to-treat cancers and viruses with clinical and preclinical research funded by investigators at academic institutions.

Each of its three core technologies is based substantially on discoveries made at and licensed from the University of Texas MD Anderson Cancer Center (MD Anderson) in Houston, Texas, and features one or more drugs that have successfully completed a Phase 1 clinical trial. Three of its six drug candidates have shown human activity in clinical trials and are currently or have been in Phase 1B/2 or Phase 2 clinical trials. Since MBI’s inception, its drugs have completed, are currently in, or have been permitted to proceed in, fourteen clinical trials. Annamycin, in a unique multilamellar lipid formulation, is the Company’s lead molecule, and MBI has recently concluded treatment in several Phase 1B/2 clinical trial for treating AML and has begun treating subjects in its Phase 3 clinical trial for the treatment of R/R AML. Annamycin was in two recently closed or concluded Phase 1B/2 clinical trials for treating Soft Tissue Sarcoma metastasized to the lungs (STS lung metastases, STS lung mets, or Advanced STS), with one physician-sponsored. The Company announced a physician-sponsored trial for Annamycin for the treatment of pancreatic cancer intended to begin in 2026. The one concluded trial has published its clinical study report. Additionally, there is another phase 1B/2 clinical trial that is physician sponsored which is investigating using WP1066 in combination with radiation for the treatment of glioblastoma, a form of brain cancer.

The physician-sponsored trials utilize primarily external funds, such as grant funds, which are not presented in these financial statements. The Company does not have manufacturing facilities, and all manufacturing activities are contracted out to third parties. Additionally, the Company does not have a sales organization. The Company’s overall strategy is to seek potential out-licensing or outsourcing opportunities with development/commercialization strategic partners who are better suited for the marketing, sales and distribution of its drugs, if approved.

In 2019, the Company sublicensed its technologies to Animal Life Sciences, Inc. (ALI), to enable research and commercialization for non-human use and share development data. As part of this agreement, ALI issued to the Company a 10% equity interest in ALI.

On May 23, 2025, the Company received a letter from the Nasdaq Stock Market LLC (Nasdaq), which notified the Company that it does not presently comply with Nasdaq’s Listing Rule 5550(b)(1) (the “Equity Rule”), which requires that the Company maintain a minimum of $2.5 million in stockholders’ equity, and that the Company also does not meet the alternatives of market value of listed securities or net income from continuing operations set forth in the Equity Rule. The letter did not have any immediate effect on the listing of the Company’s common stock on the Nasdaq Capital Market, and the Company had 45 calendar days to submit a plan to regain compliance. The Company’s plan was accepted and the Staff granted an extension of up to 180 calendar days from May 23, 2025 through November 19, 2025 to evidence compliance. If the Company is not in compliance on that date, then the Company intends to submit an appeal to extend this date, however, there can be no assurance that such appeal would be successful.

On June 27, 2025, the Company received another deficiency letter from the Staff of Nasdaq notifying the Company that for the last 30 consecutive business days the bid price for the Company’s common stock had closed below the minimum $1.00 per share requirement for continued inclusion on the Nasdaq Capital Market pursuant to Nasdaq Listing Rule 5550(a)(2) (the “Bid Price Rule”). The deficiency letter does not result in the immediate delisting of the Company’s common stock from the Nasdaq Capital Market. In accordance with Nasdaq Listing Rule 5810(c)(3)(A) (the “Compliance Period Rule”), the Company has been provided an initial period of 180 calendar days, or until December 24, 2025 (the “Compliance Date”), to regain compliance with the Bid Price Rule. If, at any time before the Compliance Date, the bid price for the Company’s common stock closes at $1.00 or more for a minimum of 10 consecutive business days as required under the Compliance Period Rule, the Staff is expected to provide written notification to the Company that it complies with the Bid Price Rule, unless the Staff exercises its discretion to extend this 10 day period pursuant to Nasdaq Listing Rule 5810(c)(3)(H). If the Company is not in compliance with the Bid Price Rule by December 24, 2025, the Company may be afforded a second 180 calendar day period to regain compliance. To qualify, the Company would be required to meet the continued listing requirement for market value of publicly held shares and all other initial listing standards for The Nasdaq Capital Market, except for the minimum bid price requirement. In addition, the Company would be required to notify Nasdaq of its intent to cure the minimum bid price deficiency, which may include, if necessary, implementing a reverse stock split. If the Company does not regain compliance with the Bid Price Rule by the Compliance Date and is not eligible for an additional compliance period at that time, the Staff will provide written notification to the Company that its common stock may be delisted. The Company would then be entitled to appeal the Staff’s determination to a NASDAQ Listing Qualifications Panel and request a hearing. There can be no assurance that, if the Company does appeal the delisting determination by the Staff to the NASDAQ Listing Qualifications Panel, that such appeal would be successful. The Company intends to monitor the closing bid price of its common stock and may, if appropriate, consider available options to regain compliance with the Bid Price Rule, which could include effecting a reverse stock split. However, there can be no assurance that the Company will be able to regain compliance with the Bid Price Rule.