Company: HURA
Filing Date: 2025-08-12
Form Type: S-1
Source: 0001193125-25-179009
Chunk: 108

Company: TuHURA Biosciences, Inc./NV
Filing Date: 2025-08-12
Form: S-1
Chunk 108
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 known to be predictive of response to checkpoint inhibitors following IFx-2.0 therapy but prior to checkpoint inhibitor rechallenge.

TuHURA’s TBS-2025 VISTA Inhibiting Antibody Clinical Development Program

TBS-2025 (f/k/a KVA-12123), a VISTA inhibiting antibody, was initially investigated by Kineta in a large Phase 1 trial either as monotherapy (n=24) or in combination with pembrolizumab (n=15) among patients with advanced, therapy refractory cancers, including, breast, lung, colorectal and ovarian cancer. The Phase 1 was an open-label, multi-center, dose-escalation trial, utilizing an accelerated Bayesian Optimal Interval (BOIN) dosing design designed to evaluate the safety, tolerability, pharmacokinetics (“PK”), immunogenicity, and tumor response of TBS-2025. TBS-2025 demonstrated a favorable safety profile at the highest dose level of 1,000 mg administered every two weeks. In this trial among patients with treatment-refractory solid tumors, no significant anti-tumor activity was observed among the 39 patients treated in the trial.

An overview of the study results is shown below:

Clinical collaboration with Merck

Kineta 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