Company: HURA
Filing Date: 2025-05-23
Form Type: 424B3
Source: 0001193125-25-125499
Chunk: 425

Company: TuHURA Biosciences, Inc./NV
Filing Date: 2025-05-23
Form: 424B3
Chunk 425
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tolerated at all dose schedules evaluated. As to efficacy, in the 21 patients that completed the study, best overall disease response to trial therapy was PR in 1 patient (including both injected
and non-injected tumor sites), SD in 4, and PD in 16. The response assessment limited to the injected site(s) only was PR in 2 patients, SD in 8, and PD in 9. Two additional patients were not evaluable at the
injected site(s) due to clinically challenging to measure dermal lesions that were not radiographically measurable. The study achieved the primary safety endpoint of the study demonstrating no grade 3 or greater toxicity in any of the 3 dose levels
examined, and as a result, a recommended phase 2 dose was determined. The study also achieved its secondary endpoint of efficacy analysis demonstrating a disease control rate of 48% among injected lesions within the first 28 days post injection,
and, as described below, a post-protocol efficacy analysis demonstrated an overall objective response rate of 64% (7 of 11 patients with Merkel cell carcinoma) after rechallenge with immune checkpoint inhibitors.

After protocol specified IT therapy, eleven (11) Merkel cell carcinoma patients and six (6) cSCC pts were treated with anti-PD(L)1 based therapy as the immediate post-protocol treatment. Five (5) of nine (9) (56%) evaluable Merkel cell carcinoma patients and one (1) of six (6) (17%) cSCC patients
experienced an objective response to this ICI rechallenge, with duration of response ongoing in four (4) patients (6+, 19+, 21+, 23+ months) and the two other responses lasting 23 and 33 months. The two (2) remaining Merkel cell carcinoma
patients were not evaluable for response from IO rechallenge due to radiation administered to the only measurable disease site(s), but both remain progression free at 11+ and 13+ months with previously progressive disease.

Of the twelve (12) patients with advanced Merkel cell carcinoma who completed treatment and protocol-directed 28-day safety evaluation follow-up period, seven patients exhibited primary resistance to first line treatment with a checkpoint inhibitor who did not receive subsequent
therapies prior to receiving IFx-2.0. Five of seven patients received single agent anti-PD(L)-1 as initial therapy while two of
seven patients received multiple CPIs as initial therapy including anti-PD-