GTBP 10-K & 10-Q changes, risk factors and insider trading

Risks Related to Our BusinessFinancial Condition and Capital Requirements

As of December 31, 2024,2025, we had approximately $4.0$6.9 million in cash and cash equivalents and restricted cash, and a working capital deficit of $1.7approximately $5.8 million, and we have incurred and expect to continue to incur significant costs in pursuit of our drug candidates. For the year ended December 31, 2024,2025, we recorded a net loss of approximately $13.2$28.4 million and used cash in operations of approximately $12.9 million. Our financial statements for the year ended December 31, 20242025 have been prepared assuming that we will continue to operate as a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business. To date, we have not generated substantial product revenues from our activities and have incurred substantial operating losses. We expect that we will continue to generate substantial operating losses for the foreseeable future until we complete development and approval of our product candidates. We willexpect to continue to fund our operations primarily through utilization of our current financial resources and additional raises of capital.

These conditions raise substantial doubt about our ability to continue as a going concern. 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 Company has evaluated the significance of the uncertainty regarding the Company’s financial condition in relation to its ability to meet its obligations, which has raised substantial doubt about the Company’s ability to continue as a going concern. While it is very difficult to estimate the Company’s future liquidity requirements, the Company believes if it is unable to obtain additional financing, existing cash resources will not be sufficient to enable it to fund the anticipated level of operations through one year from the date the accompanying financial statements are issued. There can be no assurances that the Company will be able to secure additional financing on acceptable terms.terms or that it will provide us with sufficient funds to meet our objectives. In the event the Company does not secure additional financing, the Company will be forced to delay, reduce, or eliminate some or all of its discretionary spending, which could adversely affect the Company’s business prospects, ability to meet long-term liquidity needs and the ability to continue operations.

Our business is at an early stage of development. We do not have immune-oncology products in late-stage clinical trials. We are still in the early stages of identifying and conducting research on potential therapeutic products. Our potential therapeutic products will require significant research and development and pre-clinical and clinical testing prior to regulatory approval in the United States and other countries. We may not be able to obtain regulatory approvals, enter clinical trials for any of our product candidates, or commercialize any products.products for years, if at all. Our product candidates may prove to have undesirable and unintended side effects or other characteristics adversely affecting their safety, efficacy or cost effectiveness that could prevent or limit their use. Any product using any of our technology may fail to provide the intended therapeutic benefits or achieve therapeutic benefits equal to or better than the standard of treatment at the time of testing or production.

During the year ended December 31, 2024,2025, the Company reported a net loss of $13.2approximately $28.4 million and as of December 31, 20242025, and had an accumulated deficit of approximately $695$724 million. We have not generated any revenue to date and are not profitable, and have incurred losses in each year since our inception. We do not expect to generate any product sales or royalty revenues for the foreseeable future. We expect to continue to incur significant additional operating losses for the foreseeable future as we expand research and development and clinical trial efforts.

We may not be successful in generating and/or maintaining operating cash flow, and the timing of our capital expenditures and other expenditures may not result in cash sufficient to sustain our operations through the commercialization of our product candidates. If financing is not sufficient and additional financing is not available or available only on terms that are detrimental to our long-term survival, it could have a material adverse effect on our ability to continue to function.operate. The timing and degree of any future capital requirements will depend on many factors, including:

If sufficient capital is not available, we may be required to delay, reduce the scope of or eliminate one or more of our research or product development initiatives, any of which could have a material adverse effect on our financial condition or business prospects. In addition, we may seek additional capital due to favorable market conditions or strategic considerations even if we believe we have sufficient funds for our current or future operating plans. Attempting to secure additional financing our product candidates.

We do not currently have any alternate supply for our products. If the facilities where our products are currently being manufactured or equipment were significantly damaged or destroyed, or if there were other disruptions, delays or difficulties affecting manufacturing capacity or availability of drug supply, including, but not limited to, if such facilities are deemed not in compliance with current Good Manufacturing Practice,Practice or GMP,(“GMP”), requirements, future clinical studies and commercial production for our products would likely be significantly disrupted and delayed. It would be both time-consuming and expensive to replace this capacity with third parties, particularly particularly since any new facility would need to comply with the regulatory requirements.

Our therapeutic immuno-oncology (“IO”) development programs face, and will continue to face, intense competition from pharmaceutical, biopharmaceutical biopharmaceutical and biotechnology companies, as well as numerous academic and research institutions and governmental agencies engaged in drug discovery activities or funding, both in the United States and abroad. Some of these competitors are pursuing the development of drugs and other therapies that target the same diseases and conditions that we are targeting with our product candidates. According to torecent (early 2026) industry research form Global Data,Data Thematic and Research: Immuno-Oncologyand (March 2021), as of December 2020,Markets, there are 4,822approximately 9,000 industry-sponsored clinical trials for immuno-oncology with 422 more than 1,200 drugs in development. Phase 2 trials constitute the majority of the IO pipeline,pipeline at approximately 48%, followed by early-stage molecules in Phase 1/2 and Phase 1. ForLate-stage late-stagedevelopment pipelineremains products,highly 484competitive, with over 600 clinical trials are ongoing in Phase 3, and 51 are in Phase 2/3 development.3. There are currently 22over 85 marketed immuno-oncology agents.agents Cancerglobally. vaccineWhile productscheckpoint modulators lead(specifically PD-1/PD-L1 inhibitors) remain the dominant category by revenue, the category of cancer vaccines has seen a resurgence due to breakthroughs in mRNA technology, with 9over products120 followedRNA-based byvaccine checkpointtrials modulators withcurrently 8 approved drugs.active. The indications with the most marketed IO agents in the United States are metastatic melanoma andremain non-small cell lung cancer,cancer withand 6metastatic approvedmelanoma, productsthough each.competition has intensified in triple-negative breast cancer and renal cell carcinoma. The global market value of the IO sector—encompassing bispecific antibodies, cancer vaccines, checkpoint modulators, cell therapies, and oncolytic viruses globally —has increasedreached sharplyan estimated $136 billion in 2025 and is projected to exceed $151 billion by the pastend 10of years2026, withrepresenting nearlya monumental shift from the $29 billion valuation reported in 20192019. comparedThe global market for solid tumor cancers accounts is estimated to $370be million$362 in 2010billion (according to Data Bridge Market Research).

We rely, and expect to continue to rely, upon third-party clinical research organizations (“CROs”) to execute our preclinical and clinical trials and to monitor and manage data produced by and relating to those trials. However, we may not be able to establish arrangements arrangements with CROs when needed or on terms that are acceptable to us, or at all, which could negatively affect our development efforts with respect to our drug product candidates and materially harm our business, operations and prospects.

We will have only limited control over the activities of the CROs we will engage to conduct our clinical trials. Nevertheless, we are responsible for ensuring that each of our studies is conducted in accordance with the applicable protocol, legal, regulatory and scientific standards, and our reliance on any of the CROs does not relieve us of our regulatory responsibilities. Based on our present expectations, we, our CROs and our clinical trial sites are required to comply with good clinical practices (“GCPs”), for all our product candidates in clinical development. Regulatory authorities enforce GCPs through periodic inspections of trial sponsors, principal investigators and trial sites. If we or any of our CROs fail to comply with applicable GCPs, the clinical data generated in the applicable trial may be deemed unreliable and the FDA, EMA or comparable foreign regulatory authorities may require us to perform additional clinical trials before approving a product candidate for marketing, which we may not have sufficient cash or other resources to support and which would delay our ability to generate revenue from any sales of such product candidate. In addition, our clinical trials are required to be conducted with product produced in compliance with current good manufacturing practice requirements, or cGMP. Our CROs’ failure to comply with those regulations may require us to repeat clinical trials, which would also require significant cash expenditures and delay the regulatory approval process.

There has been a limited public market for our common stock ,stock, and we do not know whether one will develop to provide adequate liquidity. Furthermore, the trading price for our common stock, should an active trading market develop, may be volatile and could be subject to wide fluctuations in per-share price.

Our outstanding warrants and options may affect the market price of our common stockstock.

As of December 31, 2024,2025, we had 2,234,32825,534,173 shares of common stock outstanding and issued and had outstanding warrants for the purchase of up to 1,120,42950,532,927 additional shares of common stock at a weighted average exercise price of of $18.85$1.74 per share, all16,344,159 of which are exercisable (subject to certain beneficial ownership limitations). In addition, we had outstanding options for the purchase of up to 124,600597,550 additional shares of common stock at a weighted average exercise price of $32.69$4.23 per share, 105,802435,883 of which are exercisable. The amount of common stock reserved for issuance may have an adverse impact on our ability to raise capital and may affect the price and liquidity of our common stock in the public market. In addition, the issuance of these shares of common stock will have a dilutive effect on current stockholders’ ownership.

Historically, the trading price of our common stock has been $5.00 per share or lower, and deemed a penny stock, as defined in Rule 3a51-1 under the Exchange Act, and subject to the penny stock rules of the Exchange Act specified in rules 15g-1 through 15g-100. Those rules require broker–dealers,broker-dealers, before effecting transactions in any penny stock, to:

Delaware law and our restated certificate of incorporation (“certificate of incorporation”),Charter, our restatedBylaws bylaws (“bylaws”) and other governing documents contain provisions that could discourage, delay or prevent a third party from acquiring us, even if doing so may be beneficial to our stockholders, which could cause our stock price to decline. In addition, these provisions could limit the price investors would be willing to pay in the future for shares of our common stock.

Some of the statements in this Annual Report on Form 10-K are “forward-looking statements” within the meaning of the safe harbor from liability established by the Private Securities Litigation Reform Act of 1995. Forward-looking statements include statements regarding our current beliefs, goals and expectations about matters such as our expected financial position and operating results, our business strategy and our financing plans. The forward-looking statements in this report are not based on historical facts, but rather reflect the current expectations of our management concerning future results and events. The forward-looking statements generally can be identified by the use of terms such as “believe,” “expect,” “anticipate,” “intend,” “plan,” “foresee,” “may,” “guidance,” “estimate,” “potential,” “outlook,” “target,” “forecast,” “likely” or other similar words or phrases. Similarly, statements that describe our objectives, plans or goals are, or may be, forward-looking statements. Forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be different from any future results, performance and achievements expressed or implied by these statements. We cannot guarantee that our forward-looking statements will turn out to be correct or that our beliefs and goals will not change. Our actual results could be very different from and worse than our expectations for various reasons. You should carefully review all information, including the discussion of risk factors under “Part I. Item 1A: Risk Factors” and elsewhere in this annual report. Any forward-looking statements in thethis Form 10-K are made only as of the date hereof and, except as may be required by law, we do not have any obligation to publicly update any forward-looking statements contained in this Form 10-K to reflect subsequent events or circumstances.

The preparation of our financial statements in conformity with accounting principles generally accepted in the United States, or GAAP,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.

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 HedgingHedging.”. 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.

Research and development expenses decreased by $668,000approximately $2.3 million for the year ended December 31, 20242025, compared to the prior year, primarily due to a decrease in projectproduction and materials costs, partially offset by an increase in scientific research costs.

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. In late January 2026, we received clearance from the FDA with respect to our IND Application in relation to GTB 3650, and we started study enrollment targeting patientsGTB-5550, with a Phase 1 dose escalation relapsed/refractorybasket AMLtrial and high grade MDS on January 21, 2025. We anticipate our direct clinical and preclinical expenses to increase in 2025 as our next generation GTB-3650 camelid nanobody productthat is in the clinic. We also planexpected to completeinitiate the product development of GTB-5550 in 2025. We do not, however, anticipate an increase in related R&D licensing and administrative costs.mid-2026.

Selling, general, and administrative expenses increasedremained relatively flat, increasing by approximatelyonly $3.4 million$182,000 for the year ended December 31, 20242025, compared to the prior year, primarily due to an increase in legal fees and settlement expenses.year.

Interest income decreased by $378,000$279,000 for the year ended December 31, 20242025, compared to the prior year primarily due to lower highly liquid and short-term investment balances.

The change in fair value of warrant liability decreased by approximately $4.0 million$559,000 for the year ended December 31, 20242025, compared to the prior year, primarily due to the decline in the Company’s stock price at December 31, 2024,2025, as compared to the prior year.

Gain on ExtinguishmentSettlement of DebtVendor Payable

Net loss increased $5,565,000approximately $15.2 million for the year ended December 31, 2024,2025, primarily due to the decrease in the change in fair value of warrantgreenshoe rights liability, and an increase in legal fees, and was partiallyslightly offset by a decrease in stock compensation and research and development expenses, all as described above.

The accompanying financial statements have been prepared assuming that we will continue as a going concern. We do not have any product candidates candidates approved for sale and have not generated any revenue from our product sales. We have sustained operating losses since inception, and 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 year ended December 31, 2024,2025, we recorded a net loss of approximately $13.2$28.4 million and used cash in operations of approximately $12.9 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, 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.

We have evaluated the significance of the uncertainty regarding our financial condition in relation to our ability to meet our obligations, 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 believewill ifneed to obtain additional financing. If we are unable to obtain additional financing, financing,we believe 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 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.

Net cash used in operating activities was approximately $12.9 million for the year ended December 31, 2024,2025, and was primarily due to a net loss of approximately $13.2$28.4 million,million and a decrease in theaccounts fairpayable valueand accrued expenses of warrant$2.6 million, offset by the reclassification the Greenshoe Right liability ofto $0.8equity amounting to approximately $17.3 million.

Net cash used in operating activities was approximately $8.9$12.9 million for the year ended December 31, 2023,2024, and was primarily due to a net loss of approximately $7.6$13.2 million, a decrease in the fair value of warrant liability of $4.8 million,$800,000, and partially offset by stock compensation of $2.2 million and an increase in accounts payable and accrued expenses of approximately $2.0 million.$900,000.

Net cash provided (used) inby financing activities for the yearsyear ended December 31, 2024 and 2023,2024, resulted primarily from proceeds from the sale, or (purchase),sale of short-term investments.

Net cash provided by financing activities was approximately $16 million for the yearsyear ended December 31, 20242025, and 2023, resulted from net proceeds from the issuance of common stockSeries L Preferred Stock and warrants, and net proceeds from the exercise of warrants for cash and inducement warrants.

We are a clinical stage biopharmaceutical company focused on the development and commercialization of novel immuno-oncology products based 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.

Our current product candidate pipeline (as of MarchJune 31,30, 2026) is summarized in the table below:

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 approximatelythe 50%first of4 patientscohorts dosed.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.

Comparison of the Three and Six Months Ended MarchJune 31,30, 2026 and 2025

Research and development expenses decreasedincreased by approximately $0.7 million for the three months ended MarchJune 31,30, 2026 compared to the same prior year period, primarily due to aan decreaseincrease in materials and production costs.

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 approximatelythe 50%first of4 patientscohorts dosed.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.

Selling, general and administrative expenses increased by approximately $1.6$2.3 million and $3.8 million for the three and six months ended March 31,June 30, 2026, respectively, compared to the same prior year period,periods, primarily due to an increase in marketing expenses, and to a lesser extent, legal and consulting fees.

ChangeLoss inon Fairinitial Valuerecognition of WarrantGreenshoe LiabilityRights liability

Net loss increaseddecreased by approximately $2.1$25.7 and $23.6 million for the three and six months ended MarchJune 31,30, 20262026, respectively, compared to the same prior year period,periods, primarily due to the prior year loss on initial recognition of Greenshoe Rights liability of $28.7 million which did not occur in the current period, slightly offset by an increase in selling, general and administrative expenses of approximately $1.5 million, and a decrease in other income of approximately $1.1 million,expenses, as described above.

The accompanying unaudited condensed financial statements have been prepared assuming that we will continue as a going concern. We do not not have any product candidates approved for sale and have not generated any revenue from our product sales. We have sustained operating 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 commonCommon stock,Stock, the issuance of preferred stock and commonCommon stock,Stock, the issuance of convertible debt instruments, and strategic collaborations. For the threesix months ended MarchJune 31,30, 2026, we recorded a net loss of approximately $2.8$7.4 million and used cash in operations of approximately $2.5$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.

Net cash used in operating activities was approximately $2.5$6.7 million for the threesix months ended MarchJune 31,30, 2026 and was primarily due to a net net loss of $2.8$7.4 million.

Net cash used in operating activities was approximately $2.2$5.2 million for the threesix months ended MarchJune 31,30, 2025 and was primarily due to a net loss of $30.9 million and a decrease in accounts payable and accrued expenses of approximately $1.3$1.6 million, andoffset by a netnon-cash loss on initial recognition of $776,000.Greenshoe Rights liability of $28.7 million.

Net cash provided by financing activities was approximately $4.6$4.9 million and $6.5 million for the threesix months ended MarchJune 31,30, 2026 and 2025, respectively, and resulted primarily from net proceeds from issuance of Series L Preferred Stock and exercise of warrants.

The following table summarizes total current assets, liabilities, and working capital for the periods ended MarchJune 31,30, 2026 and December 31, 2025:

We have no off-balance sheet arrangements as of MarchJune 31,30, 2026.