GT Biopharma, Inc.
For the period ended Mar 31, 2026. Filed May 15, 2026.
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A company's report for each of its first three quarters. The financial statements are not audited. It shows how the business has moved since the last annual report, and what management says changed.
Mar 31, 2026 · Filed May 15, 2026
GTBP$4.42-2.6%Stored close · as of Nov 6, 2026
What changed in Management’s Discussion and Analysis?
Read the current filingPrevious report: 10-Q
Period ended 2025-09-30; filed 2025-11-14.
0001493152-25-023400
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of OperationsCurrent report: 10-Q
Period ended 2026-03-31; filed 2026-05-15.
0001493152-26-023346
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of OperationsThe baseline is this issuer’s latest earlier reporting period of the same form that was filed before the current report. A previous 10-Q is a different quarter, not a year-over-year comparison. Amendments are excluded.
Compared 73 previous paragraphs and 62 current paragraphs.
36 unchanged; 21 reworded; 4 added; 16 removed; 0 previous and 1 current paragraphs rearranged.
Tables are not compared: 8 previous and 5 current tables excluded. Dates, whitespace, punctuation and numbering changes are ignored; changes to financial figures remain significant.
A changed paragraph is not evidence that risk increased or decreased. An unchanged paragraph does not establish that risk stayed the same.
Added paragraphs (4)
Current report
Critical Accounting Policies
Current report
Selling, general and administrative expenses increased by approximately $1.6 million for the three months ended March 31, 2026, compared to the same prior year period, primarily due to an increase in marketing expenses, and to a lesser extent, legal fees.
Current report
Net loss increased by approximately $2.1 million for the three months ended March 31, 2026 compared to the same prior year period, primarily due to an increase in selling, general and administrative expenses of approximately $1.5 million, and a decrease in other income of approximately $1.1 million, as described above.
Current report
Working Capital
Removed paragraphs (16)
Previous report
Organization
Previous report
The corporate predecessor of GT Biopharma, Inc, Diagnostic Data, Inc., was incorporated in the state of California in 1965. Diagnostic Data, Inc. changed its incorporation to the state of Delaware on December 21, 1972 and changed its name to DDI Pharmaceuticals, Inc. on March 11, 1985. On September 7, 1994, DDI Pharmaceuticals, Inc. merged with International BioClinical, Inc. and Bioxytech S.A. and changed its name to OXIS International, Inc. On July 17, 2017, OXIS International, Inc. changed its name to GT Biopharma, Inc.
Previous report
Critical Accounting Policies and Estimates
Previous report
Warrant Liability
Previous report
We evaluate our financial instruments to determine if such instruments are derivatives or contain features that qualify as embedded derivatives in accordance with ASC Topic 815, “Derivatives and Hedging.” For derivative financial instruments that are accounted for as liabilities, the derivative instrument is initially recorded at its fair value and is then re-valued at each reporting date, with changes in the fair value reported in the statements of operations.
Previous report
Our use of derivative financial instruments is generally limited to warrants issued by us that do not meet the criteria for equity treatment and are recorded as liabilities. We do not use financial instruments or derivatives for any trading purposes.
Previous report
Selling, general, and administrative expenses remained relatively flat, increasing by approximately $72,000 for the three months ended September 30, 2025, compared to the same prior year period. Selling, general, and administrative expenses decreased by approximately $2.2 million for the nine months ended September 30, 2025, compared to the same prior year period, and was primarily due to a significant reduction in legal fees and other cost reduction measures, and partially offset by increased marketing expenses.
Previous report
The change in fair value of warrant liability decreased by approximately $626,000 for the nine months ended September 30, 2025, compared to the same prior year period, resulting from a lesser reduction in our warrant liability primarily due to the relative decline in the Company’s stock price at September 30, 2025 as compared to the prior comparable period.
Previous report
Other
Previous report
In May 2025 the Company issued warrants underlying 24,390 shares of common stock exercisable at $2.24 per share with a fair value of approximately $44,000 in exchange for the waiver of a variable rate transaction (“VRT”). The Company classified this transaction as other income in June 30, 2025. The Company also recorded other income of $200,000 in June 2025 due to the extinguishment of an accrual of consulting fees recorded in prior years.
Previous report
Net loss decreased by approximately $300,00 and $4.1 million for the three and nine months ended September 30, 2025, respectively, compared to the same prior year periods, primarily due to a decrease research and development expenses and legal fees, as described above.
Previous report
The unaudited condensed financial statements do not include any adjustments that might be necessary if we are unable to continue as a going concern. Accordingly, the unaudited condensed financial statements have been prepared on a basis that assumes we will continue as a going concern, and which contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business.
Previous report
We have evaluated the significance of the uncertainty regarding our financial condition in relation to our ability to meet our obligations, which has raised substantial doubt about our ability to continue as a going concern. While it is very difficult to estimate our future liquidity requirements we believe if we are unable to obtain additional financing, existing cash resources will not be sufficient to enable us to fund the anticipated level of operations through one year from the date the accompanying unaudited condensed financial statements are issued. There can be no assurances that we will be able to secure additional financing on acceptable terms. In the event that we do not secure additional financing, we will be forced to delay, reduce, or eliminate some or all of our discretionary spending, which could adversely affect our business prospects, ability to meet long-term liquidity needs and the ability to continue operations.
Previous report
Investing Activities
Previous report
Net cash provided by financing activities was approximately $12.9 million for the nine months ended September 30, 2024, resulted from proceeds of the sale of short-term investments.
Previous report
Working Capital (Deficit)
Reworded paragraphs (21)
Previous wording
We are a clinical stage biopharmaceutical company focused on the development and commercialization of novel immuno-oncology products based on our proprietary Tri-specific Killer Engager (TriKE®), and Tetra-specific Killer Engager (Dual Targeting TriKE®) fusion protein immune cell engager technology platforms. Our TriKE® and Dual Targeting TriKE® platforms generate proprietary therapeutics designed to harness and enhance the cancer killing abilities of a patient’s own natural killer cells, or NK cells. Once bound to an NK cell, our moieties are designed to activate the NK cell to direct it to one or more specifically targeted proteins expressed on a specific type of cancer cell or virus infected cell, resulting in the targeted cell’s death. TriKE®s can be designed to target any number of tumor antigens, including B7-H3, HER2, CD33 and PDL1, on hematologic malignancies or solid tumors and do not require patient-specific customization. We believe our TriKE® and Dual Targeting TriKE® platforms that activate endogenous NK cells are potentially safer than T-cell immunotherapy because there is less cytokine release syndrome (CRS) and fewer neurological complications. Our preclinical data suggests that this is explained by the TriKE® dependent CD16 directed IL-15 proliferation of NK cells but little effect endogenous T cells.
Current wording
We are a clinical stage biopharmaceutical company focused on the development and commercialization of novel immuno-oncology products based on our proprietary Tri-specific Killer Engager (“TriKE®”), and Tetra-specific Killer Engager (“Dual Targeting TriKE®”) fusion protein immune cell engager technology platforms. Our TriKE® and Dual Targeting TriKE® platforms generate proprietary therapeutics designed to harness and enhance the cancer killing abilities of a patient’s own natural killer cells, (“NK cells”). Once bound to an NK cell, our moieties are designed to activate the NK cell to direct it to one or more specifically targeted proteins expressed on a specific type of cancer cell or virus infected cell, resulting in the targeted cell’s death. TriKE®s can be designed to target any number of tumor antigens, including B7-H3, HER2, CD33 and PDL1, on hematologic malignancies or solid tumors and do not require patient-specific customization. We believe our TriKE® and Dual Targeting TriKE® platforms that activate endogenous NK cells are potentially safer than T-cell immunotherapy because there is less cytokine release syndrome (CRS) and fewer neurological complications. Our preclinical data suggests that this is explained by the TriKE® dependent CD16 directed IL-15 proliferation of NK cells, with little effect on endogenous T cells.
Previous wording
Our initial work was conducted in collaboration with the Masonic Cancer Center at the University of Minnesota under a program led by Dr. Jeffrey Miller, Professor of Medicine, and the Interim Director at the Center. Dr. Miller, who also serves as our Consulting Senior Medical Director, is a recognized key opinion leader in the field of NK cell and IL-15 biology and their therapeutic potential. We have exclusive rights to the TriKE® platform and are generating additional intellectual property for specific moieties.
Current wording
Our initial work was conducted in collaboration with the Masonic Cancer Center at the University of Minnesota under a program led by Dr. Jeffrey Miller, Professor of Medicine, and the Interim Director at the Masonic Cancer Center. Dr. Miller, who also serves as our Consulting Senior Medical Director, is a recognized key opinion leader in the field of NK cell and IL-15 biology and their therapeutic potential. We have exclusive rights to the TriKE® platform and are generating additional intellectual property for specific moieties.
Previous wording
Our current product candidate pipeline is summarized in the table below:
Current wording
Our current product candidate pipeline (as of March 31, 2026) is summarized in the table below:
Previous wording
GTB-3550 was our first TriKE® product candidate and its clinical development was suspended so that we could focus resources on second-generation TriKEs®. GTB-3550 is a tri-specific killer engager (TriKE) comprised of two single-chain variable fragments (“scFv”) composed of the variable regions of the heavy and light chains of anti-CD16 and anti-CD33 antibodies and a modified form of IL-15. We studied this anti-CD16-IL-15-anti-CD33 TriKE® in CD33 positive leukemias, a marker expressed on tumor cells in acute myelogenous leukemia, or AML, and myelodysplastic syndrome, or MDS. The anti-CD33 antibody fragment in GTB-3550 was derived from the M195 humanized anti-CD33 scFv. We believe the approval of the antibody-drug conjugate gemtuzumab validates the targeting of CD33.
Current wording
GTB-3550 was our first TriKE® product candidate and its clinical development was suspended so that we could focus resources on second-generation TriKEs®. GTB-3550 is a tri-specific killer engager, or TriKE, comprised of two single-chain variable fragments (“scFv”) composed of the variable regions of the heavy and light chains of anti-CD16 and anti-CD33 antibodies and a modified form of IL-15. We studied this anti-CD16-IL-15-anti-CD33 TriKE® in CD33 positive leukemias, a marker expressed on tumor cells in acute myelogenous leukemia (“AML”) and myelodysplastic syndrome (“MDS”). The anti-CD33 antibody fragment in GTB-3550 was derived from the M195 humanized anti-CD33 scFv. We believe the approval of the antibody-drug conjugate gemtuzumab validates the targeting of CD33.
Previous wording
Our goal is to be a leader in immuno-oncology therapies targeting a broad range of indications including hematological malignancies and solid tumors. A key element of our strategy includes introducing a next-generation camelid nanobody platform. Camelid antibodies (often referred as nanobodies) are smaller than human immunoglobulin, consisting of two heavy chains instead of two heavy and two light chains. These nanobodies have the potential to have greater affinity to target antigens, potentially resulting in greater potency. We are utilizing this camelid antibody structure for all of our new TriKE® product candidates.
Current wording
Our goal is to be a leader in immuno-oncology therapies targeting a broad range of indications including hematological malignancies and solid tumors. A key element of our strategy includes introducing a next-generation camelid nanobody platform. Camelid antibodies (often referred to as nanobodies) are smaller than human immunoglobulin, consisting of two heavy chains instead of two heavy and two light chains. These nanobodies have the potential to have greater affinity to target antigens, potentially resulting in greater potency. We are utilizing this camelid antibody structure for all of our new TriKE® product candidates.
Previous wording
GTB-3650 is a TriKE® which targets CD33 on the surface of myeloid leukemias and an agonistic camelid engager to the potent activating receptor on NK cells, CD16. Use of this engager enhances the activity of wild type IL-15 included in GTB-3650. The TriKE® approach provides a novel way to specifically target these tumors by leveraging NK cells, which have been shown to mediate relapse protection in this setting, in an anti-CD33-targeted fashion. We are advancing GTB-3650 to clinical studies based on pre-clinical data showing a marked increase in potency compared to GTB-3550, which we anticipate could lead to an enhanced efficacy signal in AML and MDS. We advanced GTB-3650 through requisite preclinical studies and filed an Investigational New Drug (IND) application with the U.S. Food and Drug Administration (FDA) in December 2023. In late June 2024, the FDA cleared our IND Application for GTB-3650. We started study enrollment targeting patients with relapsed/refractory AML and high grade MDS on January 21, 2025. This initial study is testing GTB-3650 as monotherapy testing administration 2 weeks on and two weeks off (to prevent NK cell exhaustion) for at least 2 cycles of therapy, as agreed on with the FDA.
Current wording
GTB-3650 is a TriKE® which targets CD33 on the surface of myeloid leukemias and an agonistic camelid engager to the potent activating receptor on NK cells, CD16. Use of this engager enhances the activity of wild type IL-15 included in GTB-3650. The TriKE® approach provides a novel way to specifically target these tumors by leveraging NK cells, which have been shown to mediate relapse protection in this setting, in an anti-CD33-targeted fashion. We are advancing GTB-3650 to clinical studies based on pre-clinical data showing a marked increase in potency compared to GTB-3550, which we anticipate could lead to an enhanced efficacy signal in AML and MDS. We advanced GTB-3650 through requisite preclinical studies and filed an IND application with the U.S. Food and Drug Administration (the “FDA”) in December 2023. In late June 2024, the FDA cleared our IND Application for GTB-3650. We started study enrollment targeting patients with relapsed/refractory AML and high grade MDS on January 21, 2025, and we have advanced into the clinic with approximately 50% of patients dosed. This initial study is testing GTB-3650 as monotherapy testing administration 2 weeks on and two weeks off (to prevent NK cell exhaustion) for at least 2 cycles of therapy, as agreed on with the FDA.
Previous wording
GTB-5550 is a B7-H3 targeted TriKE® which targets B7-H3 on the surface of advanced solid tumors (figure above). GTB-5550 is our first dual camelid TriKE®. B7-H3 is expressed on a broad spectrum of solid tumor malignancies, allowing our team to target these malignancies through GTB-5550. Pre-clinical work has shown that this molecule has NK-cell targeted activity against a variety of solid tumors, including head and neck cancer squamous cell carcinoma (figure below), prostate cancer, breast cancer, ovarian cancer, glioblastoma, and lung cancer (amongst others). We are advancing GTB-5550 through preclinical studies and initiated a GMP manufacturing campaign in anticipation of filing an IND. A pre-IND packet was submitted to the FDA in October 2023 with a written response from the FDA in December 2023. The main question from the FDA was regarding pre-clinical toxicology and a pivot to subcutaneous dosing. The initial trial is designed as a basket trial for patients with B7-H3+ solid tumors using Monday through Friday dosing (2 weeks on and 2 weeks off to prevent immune exhaustion), and is dependent on manufacturing of clinical materials. We anticipate submission of an IND application for GTB-5550 in late December 2025 or in January 2026.
Current wording
GTB-5550 is a B7-H3 targeted TriKE® which targets B7-H3 on the surface of advanced solid tumors (figure above). GTB-5550 is our first dual camelid TriKE®. B7-H3 is expressed on a broad spectrum of solid tumor malignancies, allowing our team to target these malignancies through GTB-5550. Pre-clinical work has shown that this molecule has NK-cell targeted activity against a variety of solid tumors, including head and neck cancer squamous cell carcinoma (figure below), prostate cancer, breast cancer, ovarian cancer, glioblastoma, and lung cancer (amongst others).
Previous wording
Published data shows that GTB-7550 effectively targets CD19+ malignant cell lines and primary chronic lymphocytic leukemia (CLL). Preliminary data shows that GTB-7550 can target and eliminate normal B cells, which we are continuing to test in mice. We are currently exploring and assessing potential manufacturers of GTB-7550.
Current wording
Published data shows that GTB-7550 effectively targets CD19+ malignant cell lines and primary chronic lymphocytic leukemia. Preliminary data shows that GTB-7550 can target and eliminate normal B cells, which we are continuing to test in mice. We are currently exploring and assessing potential manufacturers of GTB-7550.
Previous wording
The preparation of our financial statements in conformity with accounting principles generally accepted in the United States, or GAAP, requires us to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosure of contingent assets and liabilities. When making these estimates and assumptions, we consider our historical experience, our knowledge of economic and market factors and various other factors that we believe to be reasonable under the circumstances. Actual results may differ under different estimates and assumptions. The accounting estimates and assumptions discussed in this section are those that we consider to be the most critical to gain an understanding of our financial statements because they inherently involve significant judgments and uncertainties.
Current wording
The preparation of our financial statements in conformity with accounting principles generally accepted in the United States (“GAAP”) requires us to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue and expenses, and related disclosure of contingent assets and liabilities. When making these estimates and assumptions, we consider our historical experience, our knowledge of economic and market factors and various other factors that we believe to be reasonable under the circumstances. Actual results may differ under different estimates and assumptions. The accounting estimates and assumptions discussed in this section are those that we consider to be the most critical to gain an understanding of our financial statements because they inherently involve significant judgments and uncertainties.
Previous wording
Comparison of the Three and Nine Months Ended September 30, 2025 and 2024
Current wording
Comparison of the Three Months Ended March 31, 2026 and 2025
Previous wording
Research and development expenses decreased by approximately $0.7 and $1.8 million for the three and nine months ended September 30, 2025, respectively, compared to the same prior year periods, primarily due to a decrease in production and material costs.
Current wording
Research and development expenses decreased by approximately $0.7 for the three months ended March 31, 2026 compared to the same prior year period, primarily due to a decrease in production costs.
Previous wording
Research and development expenses relate to our continued licensing, development and production of our most advanced TriKE® product candidates GTB-3650 and GTB-5550 along with the progression on other promising candidates. In late June 2024, we received clearance from the FDA with respect to our IND Application in relation to our next generation GTB-3650 camelid nanobody product. Study enrollment began in early 2025 and we have advanced into the clinic, enrolling patients, and performing tests for data collection throughout the year. Following our May 2025 financing we have restarted the final phase of product development of GTB-5550 and anticipate submission of an IND application for GTB-5550 in late December 2025 or in January 2026.
Current wording
Research and development expenses relate to our continued licensing, development, production, and clinical trials of our most advanced TriKE® product candidates GTB-3650 and GTB-5550 along with the progression on other promising candidates. In late June 2024, we received clearance from the FDA with respect to our IND Application in relation to our next generation GTB-3650 camelid nanobody product. Study enrollment began in early 2025 and we have advanced into the clinic with approximately 50% of patients dosed. In late January 2026, we received clearance from the FDA with respect to our IND Application in relation to GTB-5550, with a Phase 1 dose escalation basket trial with the first patient dosed in May 2026.
Previous wording
Interest income decreased by $60,000 and $237,000 for the three and nine months ended September 30, 2025, respectively, compared to the same prior year periods, due to lower money market fund and short term investment balances.
Current wording
Interest income decreased by $35,000 for the three months ended March 31, 2026 compared to the same prior year period, due to greater money market fund balances.
Previous wording
The change in fair value of warrant liability increased by approximately $137,000 for the three months ended September 30, 2025, compared to the same prior year period, resulting from a reduction in our warrant liability primarily due to the relative decline in the Company’s stock price at September 30, 2025 as compared to the prior comparable period.
Current wording
The change in fair value of warrant liability decreased by $115,000 for the three months ended March 31, 2026 compared to the same prior year period, primarily due to a relative decline in the Company’s stock price at March 31, 2026 as compared to the same prior year period.
Previous wording
In March 2025, a legal services firm currently engaged by the Company agreed to reduce the Company’s prior year unpaid fees by approximately $1 million. The Company classified this transaction as other income in June 30, 2025.
Current wording
In March 2025, a legal services firm currently engaged by the Company agreed to reduce the Company’s prior year unpaid fees by approximately $1 million.
Previous wording
The accompanying unaudited condensed financial statements have been prepared assuming that we will continue as a going concern. We do not have any product candidates approved for sale and have not generated any revenue from our product sales. We have sustained operating losses since inception, and we expect such losses to continue into the foreseeable future. Historically, we have financed our operations through public and private sales of common stock, the issuance of preferred and common stock, the issuance of convertible debt instruments, and strategic collaborations. For the nine months ended September 30, 2025, we recorded a net loss of approximately $5.3 million and used cash in operations of approximately $8.9 million. These factors raise substantial doubt about our ability to continue as a going concern within one year of the date that the financial statements are issued. In addition, the Company’s independent registered public accounting firm, in its report on the Company’s December 31, 2024, financial statements, raised substantial doubt about the Company’s ability to continue as a going concern. The financial statements do not include any adjustments that might be necessary if the Company is unable to continue as a going concern.
Current wording
The accompanying unaudited condensed financial statements have been prepared assuming that we will continue as a going concern. We do not have any product candidates approved for sale and have not generated any revenue from our product sales. We have sustained operating losses since inception, and we expect such losses to continue into the foreseeable future. Historically, we have financed our operations through public and private sales of common stock, the issuance of preferred and common stock, the issuance of convertible debt instruments, and strategic collaborations. For the three months ended March 31, 2026, we recorded a net loss of approximately $2.8 million and used cash in operations of approximately $2.5 million. These factors raise substantial doubt about our ability to continue as a going concern within one year of the date that the financial statements are issued. In addition, the Company’s independent registered public accounting firm, in its report on the Company’s December 31, 2025 financial statements, raised substantial doubt about the Company’s ability to continue as a going concern. The financial statements do not include any adjustments that might be necessary if the Company is unable to continue as a going concern.
Previous wording
Net cash used in operating activities was approximately $ 10.4 million for the nine months ended September 30, 2024 and was primarily due to a net loss of $9.4 million and a decrease in warrant liability of $0.9 million
Current wording
Net cash used in operating activities was approximately $2.5 million for the three months ended March 31, 2026 and was primarily due to a net loss of $2.8 million.
Previous wording
Net cash used in operating activities was approximately $8.9 million for the nine months ended September 30, 2025 and was primarily due to a decrease in accounts payable and accrued expenses of $2.4 million and a net loss of $5.3 million.
Current wording
Net cash used in operating activities was approximately $2.2 million for the three months ended March 31, 2025 and was primarily due to a decrease in accounts payable and accrued expenses of approximately $1.3 million, and a net loss of $776,000.
Previous wording
Net cash provided by financing activities approximately $3.0 million for the nine months ended September 30, 2024 and resulted from net proceeds from issuance of common stock and warrants.
Current wording
Net cash provided by financing activities was approximately $4.6 million for the three months ended March 31, 2026 and resulted from net proceeds from issuance of Series L Preferred Stock and warrants.
Previous wording
Net cash provided by financing activities was approximately $7.5 million for the nine months ended September 30, 2025 and resulted from net proceeds from issuance of Series L Convertible Preferred Stock and warrants, and net proceeds from the exercise of warrants for cash and inducement warrants.
Current wording
Net cash provided by financing activities was $616,000 for the three months ended March 31, 2025, resulted from the exercise of warrants for cash and inducement warrants.
Previous wording
The following table summarizes total current assets, liabilities, and working capital (deficit) for the periods ended September 30, 2025 and December 31, 2024:
Current wording
The following table summarizes total current assets, liabilities, and working capital for the periods ended March 31, 2026 and December 31, 2025:
Rearranged current paragraphs (1)
Current report — wording carried from elsewhere
We advanced GTB-5550 through requisite preclinical studies and filed an IND application with the FDA in October 2023 with a written response from the FDA in December 2023. The main question from the FDA was regarding pre-clinical toxicology and a pivot to subcutaneous dosing. In early January 2026, the FDA cleared our IND Application for GTB-5550, and our first patient was dosed in May 2026. The initial trial is designed as a basket trial for patients with B7-H3+ solid tumors using Monday through Friday dosing (2 weeks on and 2 weeks off to prevent immune exhaustion).