GT Biopharma, Inc.

Evaluation of Disclosure Controls and Procedures

Our Principal Executive Officer and Principal Financial Officer evaluated the effectiveness of our “disclosure controls and procedures” (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended), as of March 31, 2026. Based on that evaluation, we concluded that our disclosure controls and procedures were not effective as of March 31, 2026, due to a material weakness in internal control over financial reporting that was previously identified for the year ended December 31, 2025, and has not been fully remediated.

Previously Reported Material Weakness

A material weakness is a deficiency, or a combination of deficiencies, in internal control over financial reporting, such that there is a reasonable possibility that a material misstatement of the Company’s annual or interim financial statements will not be prevented or detected on a timely basis.

As described in Item 9A. “Controls and Procedures” of our Annual Report on Form 10-K for the year ended December 31, 2025, management identified a material weakness related to the Company’s failure to maintain effective controls over the accounting for complex financial transactions, specifically the proper application of ASC 480.Distinguishing Liabilities from Equity, related to certain Greenshoe Rights.

Remediation of Previously Reported Material Weakness

Subsequent to September 30, 2025, the Company implemented additional controls requiring that, prior to the execution of transactions involving stock purchase rights, derivative financial instruments, or other complex financial arrangements, management engages a qualified accounting consultant to evaluate the related accounting treatment and financial reporting implications.

While management believes these controls are appropriately designed, the material weakness will not be considered fully remediated until the controls have operated for a sufficient period of time and management has completed testing to conclude that the controls are operating effectively.

The Company will continue to monitor the effectiveness of its remediation efforts and will make refinements as necessary.

Inherent Limitations on the Effectiveness of Controls

Management does not expect that our disclosure controls and procedures or our internal control over financial reporting will prevent or detect all errors and all fraud. A control system, no matter how well conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the control systems are met. Further, the design of a control system must reflect the fact that there are resource constraints, and the benefits of controls must be considered relative to their costs. Because of the inherent limitations in a cost-effective control system, no evaluation of internal control over financial reporting can provide absolute assurance that misstatements due to error or fraud will not occur or that all control issues and instances of fraud, if any, have been or will be detected.

These inherent limitations include the realities that judgments in decision-making can be faulty and that breakdowns can occur because of a simple error or mistake. Controls can also be circumvented by the individual acts of some persons, by collusion of two or more people, or by management override of the controls. The design of any system of controls is based in part on certain assumptions about the likelihood of future events, and there can be no assurance that any design will succeed in achieving its stated goals under all potential future conditions. Projections of any evaluation of controls effectiveness to future periods are subject to risks. Over time, controls may become inadequate because of changes in conditions or deterioration in the degree of compliance with policies or procedures.

Changes in Internal Control Over Financial Reporting

There were no changes in our internal controls over financial reporting during the most recent fiscal quarter that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.