Company: HURA
Filing Date: 2025-08-12
Form Type: S-1
Source: 0001193125-25-179009
Chunk: 86

Company: TuHURA Biosciences, Inc./NV
Filing Date: 2025-08-12
Form: S-1
Chunk 86
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 checkpoints, which are mostly present on activated T cells, VISTA is predominately expressed on myeloid cells, notably MDSCs, and on quiescent T cells. Research has demonstrated that when mutated, NPM1 and DNM3TA, two of the most common mutations in AML and typically co-mutated in myelodysplasia (MDS), result in high expression of VISTA on the surface of leukemic blasts. The presence of VISTA on these cells is believed to be the primary mechanism by which leukemic cells escape immune recognition and attack, resulting in a low treatment response rate and a high level of relapse in AML.

TBS-2025 was previously investigated in a dose escalation Phase 1/2 trial, both as a monotherapy and in combination with pembrolizumab, in patients with relapsed and/or treatment-refractory advanced solid tumors. TBS-2025 was well tolerated when administered every 2 weeks at doses up to 1,000mg both in the monotherapy**

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**arm (n=24) or in the pembrolizumab combination therapy arm (n=16). Pharmacokinetic and pharmacodynamic data demonstrated greater than 90% receptor occupancy across the every two- week dosing interval. Immunocytokine analysis was consistent with the mechanism of action for VISTA inhibition on immune cells.

We believe that, in a relatively inexpensive, small Phase 2 study, we can determine if TBS-2025 can augment the response rates seen with menin inhibitors and decrease the rate of relapse in patients with mutNMP1 relapsed or refractory AML where menin inhibitors are the current standard of care. Accordingly, we are currently planning on investigating TBS-2025 in a Phase 2 trial in combination with a menin inhibitor in mutNMP1 AML.

DOR Technology Development Program

In addition to its innate immune agonist product candidates, we are using proprietary Delta Opioid Receptor (DOR) technology to develop peptidomimetic or small molecule bi-specific/bi-functional immune modulating APCs and ADCs designed to inhibit the immune suppressing effects of tumor associated MDSCs on the tumor microenvironment to prevent T cell exhaustion and acquired resistance to checkpoint inhibitors. The Company’s DOR technology was developed by scientists at Moffitt Cancer Center and TuHURA Biopharma, Inc., a separate company whose intellectual property assets we