Company: HURA
Filing Date: 2025-09-18
Form Type: S-1/A
Source: 0001193125-25-207395
Chunk: 109

Company: TuHURA Biosciences, Inc./NV
Filing Date: 2025-09-18
Form: S-1/A
Chunk 109
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eta previously entered into a clinical trial collaboration and supply agreement with Merck (known as MSD outside the U.S. and Canada) that we have assumed as a part of the Kineta acquisition. Under this collaboration, we are evaluating the safety, tolerability, PK. and anti-tumor activity of TBS-2025 alone and in combination with KEYTRUDA (pembrolizumab), Merck’s anti-PD-1 therapy, in patients with advanced solid tumors.

Pharmacokinetics (PK) and Receptor Occupancy (RO)

Pharmacokinetics, or PK, is the study of how the body interacts with TBS-2025 for the entire duration of exposure after administration. TBS-2025 exhibited a greater than dose-proportional pharmacokinetic profile in drug exposure across all doses, consistent with target-mediated drug disposition at lower doses and target saturation at higher doses.**

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**To guide the recommended Phase 2 dose decision, Kineta developed a proprietary assay to evaluate VISTA receptor occupancy (“RO”) on immune cells from patients treated with TBS-2025. This is an important metric for evaluating how well TBS-2025 is blocking the VISTA target. TBS-2025 achieved a greater than 90% VISTA RO at the 30 mg dose and a complete saturation of the target between two-dosing intervals was achieved at 1000 mg. Based on these data. the Company believes the Recommended Phase 2 Dose (RP2D) should be 750mg every two weeks.

Biomarkers

In drug development and clinical trials, biomarkers may be useful to identify patient populations for a study, monitor therapeutic response, and identify side effects. TBS-2025 demonstrated dose-proportional on-target biomarker immune responses involved in anti-tumor activity. TBS-2025 demonstrated significant efficacy-related, dose-dependent cytokine induction of CXCL10, IFNg, CCL2 (MCP1), CCL3 (MIP1α), CCL4 (MIP1ß) and CXCL8 (IL8), which are involved in immune cell activation and recruitment to the tumor microenvironment. Additionally, increases in anti-tumor immune cell subpopulations including nonclassical monocytes with an activated phenotype (increased of cell surface expression of HLA-DR and CD80), NK cells, CD4+ T cells and CD8+ T cells were observed during treatment.

TBS-