GTB-5550 / GT Biopharma - LARVOL DELTA

GT Biopharma, Inc...announced IND clearance from the FDA for GTB-5550 in multiple myeloma. (GT Biopharma Press Release) - "Phase 1 dose escalation basket trial with GTB-5550 in solid tumor patients continues to actively enroll, with an update anticipated in Q4 2026...The Phase 1a/1b trial with GTB-5550 will be the first-in-human trial of a B7-H3-targeted TriKE in multiple myeloma and will use more patient-friendly subcutaneous administration intended to extend the half-life relative to prior intravenous TriKE formulations. The Phase 1a dose escalation portion will enroll 4th line and later patients with multiple myeloma and evaluate up to 6 dose cohorts to identify the maximum tolerated dose (MTD). Following dose escalation, the Phase 1b expansion cohort will enroll a total of 25 patients treated at the MTD and further evaluate safety, tolerability, and preliminary anti-tumor activity."

First-in-human • IND • New P1 trial • Multiple Myeloma

GTB-5550 TriKE for B7H3 positive solid tumor cancers (GT Biopharma Press Release) - "The ongoing Phase 1 trial with GTB-5550 is the first nanobody TriKE tested with more patient-friendly subcutaneous dosing....Enrollment in Cohort 1 is complete and enrollment in Cohort 2 is in progress. The Company expects to provide an update in the 2H 2026. After the dose escalation phase, the Phase 1b expansion component will enroll patients with up to 7 different tumor types (castration-resistant prostate cancer, ovarian cancer, breast cancer, head and neck cancer, non-small cell lung cancer, pancreatic cancer, and bladder cancer) and further evaluate its safety, tolerability and preliminary anti-tumor activity."

P1 data • Trial status • Bladder Cancer • Breast Cancer • Castration-Resistant Prostate Cancer • Head and Neck Cancer • Non Small Cell Lung Cancer • Ovarian Cancer • Pancreatic Cancer

GT Biopharma...announced that the first patient was dosed in a Phase 1 dose escalation basket trial evaluating GTB-5550, its B7-H3-targeted natural killer (NK) cell engager for solid tumors expressing B7-H3. (GT Biopharma Press Release) - "Company anticipates providing updates in 2H 2026 as enrollment progresses through dose escalation cohorts....The Phase 1a dose escalation portion of the trial will focus primarily on enrolling prostate cancer patients and evaluate up to 6 dose levels to identify the maximum tolerated dose (MTD). After the dose escalation phase, the Phase 1b expansion component will enroll patients with up to 7 different tumor types (castration-resistant prostate cancer, ovarian cancer, breast cancer, head and neck cancer, non-small cell lung cancer, pancreatic cancer, and bladder cancer) and further evaluate its safety, tolerability and preliminary anti-tumor activity."

P1 data • Trial status • Bladder Cancer • Breast Cancer • Castration-Resistant Prostate Cancer • Epithelial Ovarian Cancer • Fallopian Tube Cancer • Head and Neck Cancer • Non Small Cell Lung Cancer • Ovarian Cancer • Pancreatic Cancer • Peritoneal Cancer • Squamous Cell Carcinoma of Head and Neck

GTB-5550 in Advanced Solid Tumors (clinicaltrials.gov) - P1 | N=175 | Recruiting | Sponsor: Masonic Cancer Center, University of Minnesota

First-in-human • New P1 trial • Oncology • Solid Tumor

GT Biopharma, Inc. entered into an Investigator Initiated Clinical Trial Agreement with the Regents of the University of Minnesota (StockTitan.net) - "Under this pact, the University will sponsor an Investigational New Drug application for IND 169118 GTB-5550 and act as sponsor investigator for a phase 1a/1b trial in select advanced solid tumors that have failed prior therapy...The study budget provides for up to approximately $3.8 million over three years, to be borne by GT Biopharma."

Licensing / partnership • Solid Tumor

Phase 1 basket trial evaluating GTB-5550 TriKE in multiple solid tumor types known to express B7-H3 remains on track to initiate mid-2026 (GT Biopharma Press Release)

New P1 trial • Bladder Cancer • Breast Cancer • Castration-Resistant Prostate Cancer • Head and Neck Cancer • Non Small Cell Lung Cancer • Ovarian Cancer • Pancreatic Cancer

Ellis Martin Report: GT Biopharma, Inc. (NASDAQ:GTBP) Advances Platform Immuno-Oncology Strategy with FDA-Cleared Solid Tumor IND; An Interview with CEO Michael Breen (ABN Newswire) - "The platform enables GT Biopharma to pursue multiple cancer indications by modifying tumor-specific targets while maintaining the same core immune-activating mechanism...The company is currently conducting a first-in-human Phase 1 clinical trial in acute myeloid leukemia (AML) and plans to expand into solid tumor indications, including breast, prostate, pancreatic, lung, bladder, ovarian, and head & neck cancers. GTB-5550 targets B7-H3, a protein highly expressed across a broad range of solid tumors....During the interview, Mr. Breen also highlighted the potential application of the TriKE(R) platform in autoimmune diseases such as lupus, where immune system dysfunction plays a central role. The company anticipates filing a future IND to explore these indications."

IND • Pipeline update • Trial status • Acute Myelogenous Leukemia • Bladder Cancer • Breast Cancer • Head and Neck Cancer • Lung Cancer • Lupus • Ovarian Cancer • Pancreatic Cancer • Prostate Cancer

GT Biopharma Announces FDA Clearance of Investigational New Drug (IND) Application for GTB-5550 TriKE, a B7-H3-Targeted Natural Killer (NK) Cell Engager for Solid Tumors Expressing B7-H3 (GlobeNewswire) - "GTB-5550 Phase 1 dose escalation basket trial expected to initiate mid-2026....The Phase 1a dose escalation portion of the trial will test up to 6 dose levels to identify the maximum tolerated dose (MTD). After the dose escalation phase , the Phase 1b expansion component of the trial will then confirm the MTD identified in the Phase 1a trial in up to 7 different possible metastatic disease cohorts (castration-resistant prostate cancer, ovarian cancer, breast cancer, head and neck cancer, non-small cell lung cancer, pancreatic cancer, and bladder cancer)..."

IND • New P1 trial • Bladder Cancer • Breast Cancer • Castration-Resistant Prostate Cancer • Head and Neck Cancer • Non Small Cell Lung Cancer • Ovarian Cancer • Pancreatic Cancer

GT Biopharma...announced the submission of an investigational new drug (IND) application to the U.S. Food and Drug Administration (FDA) in December 2025 for GTB-5550 TriKE, a B7-H3-targeted natural killer (NK) cell engager for the treatment of B7-H3 expressing solid tumor cancers. (GT Biopharma Press Release) - "'Initiation of a Phase 1 basket trial with GTB-5550 for multiple solid tumors is planned for 2026.'....Based on supportive preclinical data, the planned Phase 1 trial with GTB-5550 will be the first dual nanobody TriKE tested with more patient-friendly subcutaneous dosing. The Phase 1a dose escalation portion of the trial will test up to 7 dose levels to identify the maximum tolerated dose (MTD). The Phase 1b dose expansion component of the trial will confirm the MTD identified in the Phase 1a trial across 7 distinct metastatic disease cohorts (castration-resistant prostate cancer, ovarian cancer, breast cancer, head and neck cancer, non-small cell lung cancer, pancreatic cancer, and bladder cancer), and further evaluate its tolerability assuming the toxicity rates are similar across the groups."

IND • New P1 trial • Bladder Cancer • Breast Cancer • Castration-Resistant Prostate Cancer • Head and Neck Cancer • Non Small Cell Lung Cancer • Ovarian Cancer • Pancreatic Cancer

GT Biopharma...Provides Corporate Update (GlobeNewswire) - "Phase 1 trial evaluating GTB-3650 TriKE for relapsed or refractory (r/r) CD33 expressing hematologic malignancies continues to actively enroll with the next update anticipated in Q1 2026. GTB-5550 TriKE IND submission for B7H3-expressing solid tumors expected in late December 2025 or January 2026."

Enrollment status • IND • P1 data • Acute Myelogenous Leukemia • Myelodysplastic Syndrome • Solid Tumor

Determining Optimal NK Cell Features for Immune Engagement with Tri-specific Killer Engager Molecules (PCF 2025) - "GMP production of camB7-H3 TriKE has been completed by a qualified contractor and clinical stability studies are pending. We anticipate submission of an Investigational New Drug application to the FDA in the 4th quarter of 2025 for consideration of a phase Ia/Ib basket clinical trial with a prostate cancer specific arm and expansion cohort. Anticipated first patient dosing is April 2026."

IO biomarker • Trispecific • Genito-urinary Cancer • Prostate Cancer • Solid Tumor • IFNG • IL15 • IL2RA • IL6 • LAMP1

GT Biopharma to Participate in the H.C. Wainwright 27th Annual Global Investment Conference (GT Biopharma Press Release) - "Company remains on track for GTB-5550 TriKE IND submission for treatment of B7H3 positive solid tumors in Q4 2025"

IND • Solid Tumor

GT Biopharma Reports Second Quarter 2024 Financial Results and Provides Corporate Update (GlobeNewswire) - "GTB-3650 TriKE Phase 1 trial initiation expected in 2H 2024; initial clinical data expected in 1H 2025; GTB-5550 TriKE IND submission for treatment of B7H3 positive solid tumors expected in 1H 2025; GTB-5550 Phase 1 dose escalation basket trial initiation expected in 2025 evaluating six solid tumor types, including prostate, breast, head and neck, ovarian, lung, and GI."

IND • New P1 trial • P1 data • Breast Cancer • Gastrointestinal Cancer • Gynecologic Cancers • Head and Neck Cancer • Lung Cancer • Ovarian Cancer • Prostate Cancer • Solid Tumor

GT BIOPHARMA ANNOUNCES FDA CLEARANCE OF INVESTIGATIONAL NEW DRUG (IND) APPLICATION FOR GTB-3650, AN NK CELL ENGAGER FOR TREATMENT OF CD33+ LEUKEMIA (GT Biopharma Press Release) - "GTB-5550 TriKE IND submission for treatment of B7H3 positive solid tumors expected in Q1 2025; GTB-5550 Phase 1 dose escalation basket trial initiation expected in 2025 evaluating GTB-5550 in six solid tumor cancers, including prostate, breast, head and neck, ovarian, lung, and GI...GT Biopharma...announced FDA clearance of its IND application for GTB-3650, allowing the company to proceed with a Phase 1 clinical trial, which is anticipated to start in second half of 2024...'As we ramp up our clinical activities, we plan to start the Phase 1 trial with GTB-3650 in the coming months followed by multiple data readouts in 2025.'....The Phase 1 dose escalation study will evaluate GTB-3650 in up to six cohorts of adult patients with relapsed or refractory (r/r) CD33 expressing hematologic malignancies, including acute myeloid leukemia (AML) and high-risk myelodysplastic syndrome (MDS)."

IND • New P1 trial • P1 data • Acute Myelogenous Leukemia • Breast Cancer • Gastrointestinal Cancer • Genito-urinary Cancer • Head and Neck Cancer • Hematological Malignancies • Leukemia • Lung Cancer • Myelodysplastic Syndrome • Oncology • Ovarian Cancer • Prostate Cancer • Solid Tumor

GT Biopharma Reports Fourth Quarter and Full-Year 2023 Financial Results (GlobeNewswire) - "Remain in active dialogue with the FDA regarding IND clearance for GTB-3650, a 2nd generation nanobody TriKE for treatment of CD33+ leukemia. Phase 1 trial with GTB-3650 anticipated to start in 2H 2024. Anticipate submitting an IND for GTB-5550 targeting B7H3 for multiple solid tumors, including prostate and breast, in Q4 2024."

IND • New P1 trial • Acute Myelogenous Leukemia • Breast Cancer • Prostate Cancer

GT Biopharma Presented Positive Preclinical Data for GTB-5550, a Novel TriKE Molecule for Targeted Prostate Cancer Treatment During the Society for Immunotherapy of Cancer (SITC) 2023 Annual Meeting (GlobeNewswire) - "GT Biopharma...announced positive preclinical data in highlighting GTB-5550’s potential in prostate cance...at the Society for Immunotherapy of Cancer (SITC) Annual Meeting 2023....Key findings demonstrated that normal donor and prostate cancer patient NK cells displayed better, specific, degranulation against prostate cancer cell lines in the presence of PSMA or B7H3 TriKEs....The TriKE molecules displayed improved tumor control, compared to IL-15 control or no treatment, in xenogeneic models of prostate cancer."

Preclinical • Prostate Cancer

GT Biopharma Reports Second Quarter 2023 Financial Results (GlobeNewswire) - "GT Biopharma, Inc...today announced second quarter 2023 results for the period ended June 30, 2023....'We expect to advance GTB-3650, a second generation nanobody TriKE® for the treatment of CD33+ leukemia, with GTB-5550 for the treatment of B7H3+ solid tumors to follow'...The Company had cash, cash equivalents and short-term investments of $18.0 million as of June 30, 2023, compared to $16.5 million as of December 31, 2022. We expect ample runway to fund operations into Q3 2024....R&D expenses for the three months and six months ended June 30, 2023 were $2.1 million and $3.7 million, compared to $1.1 million and $3.2 million for the same comparable periods of 2022."

Commercial • Hematological Malignancies • Leukemia • Oncology • Solid Tumor

GT Biopharma Reports First Quarter 2023 Financial Results and Provides Corporate Update (GlobeNewswire) - "'...we expect to submit an investigational new drug (IND) filing with the U.S. Food and Drug Administration for GTB-3650 in the 2H 2023'...The Company anticipates that the IND submission of GTB-5550 will follow after GTB-3650....R&D expenses for the first quarter of 2023 were $1.7 million compared to $2.1 million for the same quarter in 2022. Research and development expenses are related to our continued development and production of our most advanced TriKE® product candidates GTB-3650 and GTB-5550 along with the progression of other promising product candidates. R&D expenses decreased over the previous year primarily due to reduction in in-house staff and compensation to consultants as we prepare to advance our next generation GTB-3650 camelid nanobody product into the clinic."

Commercial • IND • Oncology

B7-H3 Trike Enhances Killing of Myeloid Derived Suppressor Cells in Multiple Myeloma (ASH 2022) - "B7-H3 TriKE may be particularly useful for patients with bone lesions or as consolidative therapy. Commercial manufacturing of B7-H3 TriKE (GTB-5550) has begun, and a phase I trial is expected in late 2023."

Myeloid-derived suppressor cells • Bone Marrow Transplantation • Breast Cancer • Hematological Malignancies • Multiple Myeloma • Oncology • Solid Tumor • Transplantation • CD14 • CD276 • CD33 • CSF2 • IL15 • IL6 • ITGAM • S100A8 • SDC1 • TNFRSF11A • TRAP

Tri-specific killer engagers target natural killer cells towards mesothelioma (SITC 2022) - "Conclusions GTB-5550 drove NK cell responses towards all mesothelioma subtypes, while cam1615SS1 successfully targeted epithelial peritoneal mesothelioma. In future studies we aim to combine TriKE with immune checkpoint inhibitors to test their potential to drive innate immune responses in the context of currently approved therapies."

IO biomarker • Lung Cancer • Malignant Pleural Mesothelioma • Mesothelioma • Oncology • Sarcoma • Solid Tumor • CD276 • IFNG • IL15 • MSLN

GT Biopharma Presents Two Posters at the Society for Immunotherapy of Cancer’s (SITC) 37th Annual Meeting (GlobeNewswire) - "GT Biopharma...will present two poster presentations at the Society for Immunotherapy of Cancer’s 37th Annual Meeting (SITC 2022)....TriKEs cam1615SSS1 and GTB-5550 were tested across multiple mesothelioma cell lines in particular cell lines that were present in pleural and peritoneal lines. TriKEs targeting mesothelin or B7H3 induce NK cell degranulation and cytokine production and in the presence of cam1615SSS1 or GTB-5550, NK cells control peritoneal mesothelioma in three-dimensional spheroid cultures."

Preclinical • Lung Cancer • Mesothelioma • Oncology • Solid Tumor • Thoracic Cancer

B7H3-targeted tri-specific killer engagers deliver IL-15 to NK cells but not T-cells, and specifically target solid tumors as a pan-tumor antigen strategy mediated through NK cells (ESMO 2022) - "As proof of concept, a clinical trial of GTB-3550 (a CD33-targeted Tri-specific Killer Engager [TriKE] in AML) induced endogenous NK cell expansion and activation in refractory AML patients. Here we developed GTB-5550 (a B7H3 TriKE) as a novel dual camelid (cam) TriKE containing WT IL-15 and comprised of two cam engagers: targeting CD16 on NK cells and B7H3 on multiple solid tumors...Conclusions B7H3 TriKE delivers an NK cell specific IL-15 signal to expand NK cells and is highly specific against a broad array of cancers. Clinical manufacturing is underway with an IND planned to open clinical trials in 2023 in a number of solid tumors and multiple myeloma."

Pan tumor • Acute Myelogenous Leukemia • Brain Cancer • Glioblastoma • Hematological Malignancies • Multiple Myeloma • Oncology • Ovarian Cancer • Solid Tumor • CD276 • CD33 • IL15 • LAMP1

GT Biopharma Poster Presentation and Mini Oral Session at ESMO Congress 2022 Demonstrates GTB-5550 TriKE Ability to Specifically Target and Efficiently Kill Multiple B7H3+ Solid and Hematologic Malignancies (GlobeNewswire) - "GT Biopharma... announced highlights of an accepted abstract...for poster presentation both virtually at the European Society for Medical Oncology ('ESMO') Congress 2022....GTB-5550 gives a robust and NK cell specific proliferation signal compared to IL-15 alone; GTB-5550 specifically targets B7-H3+ cells; GTB-5550 effectively induced NK cell degranulation and interferon gamma production in response to various prostate, brain tumor (atypical rhabdoid/teratoid), HNSCC, multiple myeloma, sarcoma, ovarian, and myeloid malignancies; GTB-5550 TriKE In vivo activity in xenogeneic models of human tumor is underway and already validating in vitro studies."

Preclinical • Brain Cancer • CNS Tumor • Genito-urinary Cancer • Gynecologic Cancers • Head and Neck Cancer • Hematological Malignancies • Multiple Myeloma • Oncology • Ovarian Cancer • Prostate Cancer • Solid Tumor

GT Biopharma Affirms Manufacturing Timeline For Lead Investigational Asset GTB-3650 (GlobeNewswire) - "GT Biopharma...announced entering into a Settlement and Investment Agreement (the 'Agreement') with its contract manufacturing partner Cytovance Biologics. The signed Agreement, covers all work required to facilitate the registration of an investigational new drug (IND) filing with the U.S. Food and Drug Administration ('FDA') of its lead investigational asset GTB-3650....The Company now expects to file its investigational new drug ('IND') application with the FDA for its GTB-3650 product no later than March 31, 2023, and to file its IND application with the FDA for its GTB-5550 product no later than June 30, 2023."

IND • Licensing / partnership • Acute Myelogenous Leukemia • Hematological Malignancies • Leukemia • Myelodysplastic Syndrome • Oncology

GT Biopharma Reports Second Quarter Fiscal 2022 Financial Results and Business Update (GlobeNewswire) - "We expect to file an Investigational New Drug (IND) application for GTB-3650 in the first half of 2023, subsequently followed by an IND application for GTB-5550."

IND • Oncology