Immutep Announces Successful Completion of FDA Project Optimus Requirements

Rhea-AI Summary

Immutep (NASDAQ: IMMP) announced the FDA has confirmed completion of Project Optimus requirements and agreed that 30mg is the optimal biological dose for eftilagimod alfa (efti).

The dosing agreement is described as a major de-risking step for efti’s oncology programs and a building block toward potential future BLA filings.

Immutep said the global TACTI-004 (KEYNOTE-F91) Phase III registrational trial in first-line advanced/metastatic NSCLC (efti + pembrolizumab + chemotherapy) is now in the process of opening clinical sites in the United States.

Positive

• FDA confirmed 30mg as efti optimal biological dose
• TACTI-004 (KEYNOTE-F91) Phase III registrational trial opening US sites

Negative

• None.

Insights

Clinical Development Strategist

FDA agrees 30mg as efti's optimal biologic dose; Phase III registrational study now opening US sites.

Agreement on a 30mg optimal biological dose for eftilagimod alfa (efti) clarifies a critical regulatory requirement and removes a major design uncertainty for ongoing oncology programs. This alignment directly supports the global TACTI-004 (KEYNOTE-F91) Phase III pathway and strengthens the procedural basis for future BLA filings by fixing dose selection for pivotal efficacy and safety readouts.

Key dependencies remain the execution fidelity of the Phase III trial and the therapy combination with pembrolizumab plus chemotherapy. Risks include operational challenges starting US sites and the need for robust safety and efficacy data at the agreed dose to satisfy registrational endpoints. The announcement itself does not report clinical outcomes or regulatory approval.

Watch clinical site activation and enrollment pacing in the United States over the next 6–18 months, and monitor upcoming interim and primary endpoint readouts once scheduled. Milestones to track include full site approval, enrollment milestones, and any disclosed efficacy or safety metrics from the TACTI-004 trial.

• Confirmation of 30mg efti as optimal biological dose relevant for Immutep’s oncology pipeline and potential future Biological License Applications (BLA)
• Registrational TACTI-004 (KEYNOTE-F91) Phase III trial in first line non-small cell lung cancer now in process of opening clinical sites in the United States

SYDNEY, AUSTRALIA, Oct. 13, 2025 (GLOBE NEWSWIRE) -- Immutep Limited (ASX: IMM; NASDAQ: IMMP) (“Immutep” or “the Company”), a late-stage immunotherapy company targeting cancer and autoimmune diseases, today announces that positive and straightforward feedback has been received from the US Food and Drug Administration (“FDA”) regarding the successful completion of Project Optimus requirements and agreement on 30mg as the optimal biological dose for eftilagimod alfa (efti).

Immutep’s Chief Development Officer, Christian Mueller, said, “We are very thankful for the FDA’s positive feedback and productive discussions over the past few years. The alignment on efti’s optimal biologic dose has strategic relevance to our efti oncology programs and is a major de-risking event and building block towards future BLA filings. We are excited to successfully conclude this chapter of efti’s clinical development and are intently focused on bringing this novel immunotherapy to market to help address the needs of cancer patients worldwide.”

The agreement with the FDA on efti’s optimal biological dosing carries strategic importance in the ongoing and future clinical development of this first-in-class immunotherapy, including the global TACTI-004 (KEYNOTE-F91) Phase III trial evaluating efti in combination with MSD’s (Merck & Co., Inc., Rahway, NJ, USA) anti-PD-1 therapy KEYTRUDA^® (pembrolizumab), and chemotherapy as first-line treatment for advanced or metastatic non-small cell lung cancer (1L NSCLC), regardless of PD-L1 expression. With the conclusion of Project Optimus, this registrational study is now in process of opening sites in the United States.

About Eftilagimod Alfa (Efti)
Efti is a novel immunotherapy that directly activates antigen-presenting cells or APCs (e.g. dendritic cells, monocytes) via the MHC Class II pathway to fight cancer. As an MHC Class II agonist, its activation of APCs engages the adaptive and innate immune system to initiate a broad anti-cancer immune response. This includes priming and activating cytotoxic T cells as well as generating important co-stimulatory signals & cytokines that further boost the immune system’s ability to combat cancer.

Efti is under evaluation for a variety of solid tumours including non-small cell lung cancer (NSCLC) in a pivotal Phase III trial called TACTI-004 (KEYNOTE-F91), as well as head and neck squamous cell carcinoma (HNSCC), soft tissue sarcoma, and breast cancer. Its favourable safety profile enables various combinations like with anti-PD-[L]1 immunotherapy, radiotherapy, and/or chemotherapy. Efti has received Fast Track designation in first line HNSCC and in first line NSCLC from the United States Food and Drug Administration (FDA).

About Immutep
Immutep is a late-stage biotechnology company developing novel immunotherapies for cancer and autoimmune disease. The Company is a pioneer in the understanding and advancement of therapeutics related to Lymphocyte Activation Gene-3 (LAG-3), and its diversified product portfolio harnesses LAG-3’s ability to stimulate or suppress the immune response. Immutep is dedicated to leveraging its expertise to bring innovative treatment options to patients in need and to maximise value for shareholders. For more information, please visit www.immutep.com.

KEYTRUDA^® is a registered trademark of Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.

Australian Investors/Media:
Eleanor Pearson, Sodali & Co.
+61 2 9066 4071; eleanor.pearson@sodali.com

U.S. Investors/Media:
Chris Basta, VP, Investor Relations and Corporate Communications
+1 (631) 318 4000; chris.basta@immutep.com

FAQ

What did Immutep announce about efti dosing on October 13, 2025 (IMMP)?

The FDA agreed that 30mg is the optimal biological dose for eftilagimod alfa (efti).

How does the FDA Project Optimus outcome affect Immutep’s BLA prospects for IMMP?

Immutep said the dosing agreement is a major de-risking event and a building block toward future BLA filings.

What is the status of the TACTI-004 (KEYNOTE-F91) Phase III trial for IMMP?

The registrational Phase III trial in first-line advanced/metastatic NSCLC is now in process of opening US sites.

Which therapy is efti being combined with in the TACTI-004 (KEYNOTE-F91) trial (IMMP)?

Efti is evaluated in combination with MSD’s anti-PD-1 therapy KEYTRUDA (pembrolizumab) and chemotherapy.

Does the FDA dosing agreement apply to all efti oncology programs for IMMP?

Immutep described the 30mg dosing agreement as strategically relevant to its ongoing and future efti oncology programs.

Will the TACTI-004 (KEYNOTE-F91) trial enroll patients regardless of PD-L1 status (IMMP)?

Yes; the Phase III trial is described as first-line NSCLC enrollment regardless of PD-L1 expression.