Company: HURA
Filing Date: 2025-05-23
Form Type: 424B3
Source: 0001193125-25-125499
Chunk: 445

Company: TuHURA Biosciences, Inc./NV
Filing Date: 2025-05-23
Form: 424B3
Chunk 445
---
 trials are typically conducted in three sequential phases that may overlap or be combined:

| • |     | phase 1. The investigational biological product candidate is initially introduced into human subjects to test for                                                                                                                           
 safety, dosage tolerance, absorption, metabolism, distribution and excretion. The initial human testing is often conducted in patients, rather than in healthy volunteers, in the case of products for severe or life-threatening diseases. |

| • |     | phase 2. The biological product is evaluated in a limited patient population to identify possible safety risks            
 (adverse effects), optimize dosing and preliminarily evaluate the efficacy of the product for specific targeted diseases. |

| • |     | phase 3. Clinical trials are undertaken in an expanded patient population to further evaluate dosage, clinical                                                                                                                                   
 efficacy, and safety, often at geographically dispersed trial sites. These clinical trials are intended to establish the overall risk to benefit ratio of the investigational product and provide, if appropriate, an adequate basis for product 
 labeling. These trials may include comparisons with placebo and/or other comparator treatments. The duration of treatment is often extended to mimic the actual use of a product during marketing.                                               |

Post-approval clinical trials, sometimes referred to as phase 4 clinical trials, may be conducted after initial marketing approval. These clinical trials are used to gain additional experience from the treatment of patients in the intended therapeutic indication, particularly for long-term safety follow-up.In certain instances, the FDA may mandate the performance of phase 4 clinical trials as a condition of approval of a BLA. Progress reports detailing the results of the clinical trial must be submitted at least annually to the FDA and more frequently if serious adverse events, or SAEs, occur. The FDA or the trial sponsor may suspend or terminate a clinical trial at any time on various grounds, including a finding that the research participants are being exposed to an unacceptable health risk. Similarly, an IRB can suspend or terminate approval of a clinical trial at its institution if the clinical trial is not being conducted in accordance with the clinical protocol, GCP, or other IRB requirements, or if the investigational product has been associated with unexpected serious harm to patients. Additionally, some trials are overseen by an independent group of qualified experts organized by the trial sponsor known as the data safety monitoring board or committee. This group provides authorization for whether a trial may move forward at designated checkpoints. During the development of a new drug or biological product, sponsors have the opportunity to meet with the FDA at certain points, including prior