GT Biopharma, Inc.

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 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.

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 the first 4 cohorts now enrolled. 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

Comparison of the Three Months Ended March 31, 2026 and 2025

Current wording

Comparison of the Three and Six Months Ended June 30, 2026 and 2025

Previous wording

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 wording

Research and development expenses increased by approximately $0.7 million for the three months ended June 30, 2026 compared to the same prior year period, primarily due to an increase in materials and production costs.

Previous 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.

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 the first 4 cohorts now enrolled. 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

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 wording

Selling, general and administrative expenses increased by approximately $2.3 million and $3.8 million for the three and six months ended June 30, 2026, respectively, compared to the same prior year periods, primarily due to an increase in marketing expenses, and to a lesser extent, legal and consulting fees.

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 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.

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 stock and Common Stock, the issuance of convertible debt instruments, and strategic collaborations. For the six months ended June 30, 2026, we recorded a net loss of approximately $7.4 million and used cash in operations of approximately $6.7 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 $2.5 million for the three months ended March 31, 2026 and was primarily due to a net loss of $2.8 million.

Current wording

Net cash used in operating activities was approximately $6.7 million for the six months ended June 30, 2026 and was primarily due to a net loss of $7.4 million.

Previous 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.

Current wording

Net cash used in operating activities was approximately $5.2 million for the six months ended June 30, 2025 and was primarily due to a net loss of $30.9 million and a decrease in accounts payable and accrued expenses of approximately $1.6 million, offset by a non-cash loss on initial recognition of Greenshoe Rights liability of $28.7 million.

Previous 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.

Current wording

Net cash provided by financing activities was approximately $4.9 million and $6.5 million for the six months ended June 30, 2026 and 2025, respectively, and resulted primarily from net proceeds from issuance of Series L Preferred Stock and exercise of warrants.