TuHURA Biosciences, Inc. Initiates Phase 1b/2a Study of IFx-Hu2.0 as an Adjunctive Therapy to Keytruda® (pembrolizumab) in First Line Treatment for Metastatic Merkel Cell Carcinoma of Unknown Primary Origin (MCCUP)
- FDA's Oncology Center of Excellence support through Project Front Runner Initiative for accelerated approval pathway
- Special Protocol Assessment Agreement secured with FDA for Phase 3 trial
- Potential to expand treatment to 30% more MCC patients who present without primary skin lesions
- Previous demonstration of IFx-Hu2.0's effectiveness in overcoming CPI resistance in multiple cancer types
- Possibility of skipping post-approval confirmatory trial if PFS endpoint is met
- Partial clinical hold on Phase 3 trial needs to be lifted
- Small patient sample size (9 patients) in Phase 1b/2a trial
- Results not expected until Q4 2025 or early Q1 2026
Insights
TuHURA's IFx-Hu2.0 trial could expand treatment options for deep-seated MCC tumors, potentially applicable across multiple cancer types.
TuHURA's initiation of this Phase 1b/2a trial strategically addresses a critical unmet need in Merkel Cell Carcinoma by targeting patients with deep-seated tumors without cutaneous manifestations - approximately
The mechanism of action is particularly compelling - IFx-Hu2.0 functions as an innate immune agonist designed to overcome primary resistance to checkpoint inhibitors. Previous data demonstrated systemic anti-tumor responses (abscopal effect) when injected into accessible tumors, and this study extends that approach to internal organs.
The trial's structure shows careful consideration of risk mitigation: enrolling just 9 patients (3 per lesion type in liver, lung, and retroperitoneum) allows rapid safety assessment while still generating meaningful data across diverse anatomical sites. The primary endpoint focuses on safety and feasibility at day 49, with secondary efficacy assessments at 3 and 6 months.
If successful, this approach could be transformative beyond MCC. The underlying premise - that IFx-Hu2.0's mechanism addresses tumor-agnostic resistance pathways rather than cancer-specific targets - presents significant therapeutic potential across multiple tumor types with poor checkpoint inhibitor response.
TuHURA advances dual clinical paths for IFx-Hu2.0, with FDA fast-track potential and expanded market applications.
This Phase 1b/2a trial represents a calculated strategic expansion that complements TuHURA's primary development program. By targeting metastatic MCC patients with deep-seated tumors, the company addresses the approximately
The regulatory pathway shows exceptional alignment with FDA objectives. The company has secured a Special Protocol Assessment for their Phase 3 trial under the FDA's accelerated approval pathway, with the agency's Oncology Center of Excellence actively engaged through their Project Front Runner Initiative. Most notably, if progression-free survival data is positive, confirmatory trials may be waived - potentially reducing time to market by years.
TuHURA's clinical development timeline establishes multiple catalysts over the next 12-18 months. The company expects to satisfy requirements to lift the partial clinical hold by Q2 2025, initiate the pivotal Phase 3 trial shortly thereafter, and generate data from this Phase 1b/2a study by Q4 2025 or early Q1 2026.
Management's vision extends well beyond MCC. Their statement that IFx-Hu2.0's mechanism "should be independent of the type of cancer treated" signals a tumor-agnostic development strategy. Success in this small trial could justify expansion into multiple tumor types that demonstrate poor checkpoint inhibitor response - substantially increasing the drug's potential market opportunity.
Phase 1b/2a trial designed to evaluate the safety and feasibility of IFx-Hu2.0 in combination with Keytruda® when administered via Interventional Radiology (IR) in patients with deep- seated tumors without associated cutaneous tumors
"Like our planned Phase 3 accelerated approval trial, this Phase 1b/2a trial will also investigate the ability of IFx-Hu2.0 to increase the anti-tumor response rate when used alongside Keytruda® in first line treatment of CPI naïve, metastatic MCC. However, unlike the planned Phase 3 study, these are patients without skin lesions who present with metastatic deep-seated tumors in the liver, lungs or retropertitoneum (abdomen). Up to
"If feasibility and safety is demonstrated for IFx-Hu2.0 and Keytruda® when radiologically administered to deep-seated tumors, we plan to extend enrollment to a variety of non-MCC cancers that are known not to respond or respond poorly to CPIs. Since the underlying biology of why tumors don't respond to CPIs is for the most part the same, then the mechanism of how IFx-Hu2.0 overcomes that resistance to CPIs should be independent of the type of cancer treated. We have previously demonstrated that IFx-Hu2.0 can overcome CPI resistance in melanoma, squamous cell, and Merkel cell carcinoma, three unrelated types of skin cancers. If successful, this trial could expand the potential benefit of IFx-Hu2.0 to a wide variety of cancers," added Dr. Bianco.
The Phase 1b/2a trial of IFx-Hu2.0 is a multicenter, open-label trial designed to assess the safety and feasibility of IFx-Hu2.0 as adjunctive therapy to pembrolizumab in adult patients with non-cutaneous MCC. The trial is designed to enroll a total of nine non-cutaneous MCC patients with either hepatic, pulmonary, or retroperitoneal lesions, enrolling three patients per lesion type (NCT06940440). Each patient will receive IFx-Hu2.0 (0.1 mg) injected into a single visceral tumor once a week for three weeks. Within 48 hours of the first IFx-Hu2.0 injection, patients will receive pembrolizumab, followed by pembrolizumab every three weeks for six months. The primary endpoint of the study is safety and feasibility of IFx-Hu2.0 adjuvant therapy evaluated 28 days following the last dose of IFx-Hu2.0, or Day 49 from the first IFx-Hu2.0 infusion. The study will also evaluate key secondary endpoints, including efficacy per RECIST 1.1 criteria at three months and six months. Data from the trial is anticipated by the end of Q4 2025 or early Q1 2026.
TuHURA is also preparing to initiate a single, randomized, placebo-controlled Phase 3 accelerated approval trial of IFx-2.0 administered as an adjunctive therapy to Keytruda® (pembrolizumab) versus Keytruda® plus placebo in first-line treatment for checkpoint inhibitor-naïve patients with advanced or metastatic MCC (NCT06947928). The primary endpoint in the Phase 3 trial will be overall response rate (ORR) at approximately 24 weeks, with a secondary endpoint of progression free survival (PFS) per RECIST 1.1 criteria. The Company has reached agreement with
Based on data generated in TuHURA's Phase 1b trial of IFx-Hu2.0 in CPI naïve patients with advanced or metastatic MCC who progressed receiving CPI therapy, FDA's Oncology Center of Excellence (OCE), consistent with the FDA's Project Front Runner Initiative, asked the Company to consider a first-line randomized placebo controlled trial of Keytruda® plus placebo or IFx-Hu2.0. The FDA also agreed that the trial could be conducted under their accelerated approval pathway with the use of Objective Response Rate (ORR) as the primary endpoint. The FDA also asked the Company to consider incorporating into its accelerated approval trial a key secondary end point of Progression Free Survival (PFS), which, if successfully achieved without a detriment to overall survival at the time of analysis, may result in the Company not being required to conduct a post approval confirmatory trial, and this single trial could potentially fulfill requirement for regular approval. The Company and the FDA have entered into a Special Protocol Assessment Agreement for the planned Phase 3 trial.
About TuHURA Biosciences, Inc.
TuHURA Biosciences, Inc. (Nasdaq: HURA) is a Phase 3 immuno-oncology company developing novel technologies to overcome primary and acquired resistance to cancer immunotherapy, two of the most common reasons cancer immunotherapies fail to work or stop working in the majority of patients with cancer.
TuHURA's lead innate immune agonist, IFx-2.0, is designed to overcome primary resistance to checkpoint inhibitors. TuHURA is preparing to initiate a single randomized placebo-controlled Phase 3 registration trial of IFx-2.0 administered as an adjunctive therapy to Keytruda® (pembrolizumab) compared to Keytruda® plus placebo in first line treatment for advanced or metastatic Merkel Cell Carcinoma.
In addition to its innate immune agonist product candidates, TuHURA is leveraging its Delta Opioid Receptor technology to develop first-in-class, bi-specific antibody drug conjugates and antibody peptide conjugates targeting Myeloid Derived Suppressor Cells to inhibit their immune-suppressing effects on the tumor microenvironment to prevent T cell exhaustion and acquired resistance to checkpoint inhibitors and cellular therapies.
For more information, please visit www.tuhurabio.com and connect with TuHURA on Facebook, X, and LinkedIn.
IMPORTANT ADDITIONAL INFORMATION REGARDING PROPOSED MERGER WITH KINETA, INC.
In connection with the proposed acquisition by merger of Kineta, Inc. ("Kineta") by TuHURA (the "Merger"), TuHURA filed with the
A definitive copy of the Joint Proxy Statement/Prospectus will be mailed to Kineta and TuHURA stockholders when that document is final. Investors and stockholders will be able to obtain free copies of the documents filed or that will be filed with the SEC by TuHURA, when they become available, through the website maintained by the SEC at www.sec.gov. The documents filed by TuHURA with the SEC may also be obtained free of charge at TuHURA's website at www.tuhurabio.com or upon written request to: TuHURA, 10500 University Drive, Suite 110, Tampa, Florida 33612.
NO OFFER OR SOLICITATION
This press release is not a proxy statement or solicitation of a proxy, consent or authorization with respect to any securities or in respect of the Merger and is not intended to and does not constitute an offer to sell or the solicitation of an offer to buy the securities of TuHURA or Kineta, nor shall there be any sale of any such securities in any state or jurisdiction in which such offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of such state or jurisdiction. No offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act.
PARTICIPANTS IN THE SOLICITATION
TuHURA and Kineta and their respective directors and officers and other members of management may, under SEC rules, be deemed to be participants in the solicitation of proxies from stockholders in connection with the Merger and other matters that may be set forth in the Joint Proxy Statement/Prospectus. Information about TuHURA's directors and executive officers is set forth in TuHURA's filings with the SEC, including TuHURA's Form 10-K filed on March 31, 2025. Additional information regarding the direct and indirect interests, by security holdings or otherwise, of those persons and other persons who may be deemed participants in the solicitation of proxies in the Merger may be obtained by reading the Joint Proxy Statement/Prospectus when it becomes available. You may obtain free copies of these documents as described above under "IMPORTANT ADDITIONAL INFORMATION."
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS
This press release contains certain "forward-looking statements" within the meaning of, and subject to the safe harbor created by, Section 27A of the Securities Act, Section 21E of the Exchange Act of 1934, as amended, and the Private Securities Litigation Reform Act of 1995. These Forward-looking statements are based only on our current beliefs, expectations, and assumptions regarding the future of our business, future plans and strategies, projections, anticipated events, and other future conditions. In some cases you can identify these statements by forward-looking words such as "believe," "may," "will," "estimate," "continue," "anticipate," "intend," "could," "should," "would," "project," "plan," "expect," "goal," "seek," "future," "likely" or the negative or plural of these words or similar expressions. Examples of such forward-looking statements include but are not limited to express or implied statements regarding TuHURA's expectations, hopes, beliefs, intentions or strategies regarding the future and include, without limitation, statements regarding TuHURA's IFx-Hu2.0 product candidate and anticipated Phase 3 trial and its recently initiated Phase 1b/2a trial, its potential acquisition by merger of Kineta Inc., and any developments or results in connection therewith and the anticipated regulatory pathway and timing of TuHURA's development programs, studies and trials. In addition, any statements that refer to projections, forecasts or other characterizations of future events or circumstances, including any underlying assumptions, are forward-looking statements. You are cautioned that such statements are not guarantees of future performance and that actual results or developments may differ materially from those set forth in these forward-looking statements. Factors that could cause actual results to differ materially from these forward-looking statements are described in detail in our registration statements, reports and other filings with the SEC, which are available on the combined company's website, and at www.sec.gov.
The forward-looking statements and other information contained in this press release are made as of the date hereof, and TuHURA does not undertake any obligation to update publicly or revise any forward-looking statements or information, whether as a result of new information, future events or otherwise, unless so required by applicable securities laws. Nothing herein shall constitute an offer to sell or the solicitation of an offer to buy any securities.
Investor Contact:
Monique Kosse
Gilmartin Group
Monique@GilmartinIR.com
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