Full Press Release Details
Immutep s Efti in Combination with MSD s KEYTRUDA Leads to Positive
Efficacy with Favourable Safety in First Line Head and Neck Cancer
SYDNEY, AUSTRALIA September 16, 2024
Immutep Limited (ASX: IMM; NASDAQ: IMMP) ( Immutep or the Company ), a clinical-stage biotechnology company developing novel LAG-3 immunotherapies for cancer and autoimmune
disease, today announces positive efficacy and safety results from the TACTI-003 Phase IIb trial evaluating eftilagimod alpha (efti) in combination with MSD s (Merck & Co., Inc., Rahway, NJ, USA)
anti-PD-1 therapy KEYTRUDA (pembrolizumab) as first-line treatment of recurrent or metastatic head and neck
squamous cell carcinoma patients (1L HNSCC).
These results with a data cut-off of 11 March 2024 were
selected as a Proffered Paper oral presentation at the European Society for Medical Oncology (ESMO) Congress 2024 and were presented by Claus Kristensen, M.D., Ph.D., Head of Section for Thoracic and Head and Neck Oncology, Rigshospitalet,
Copenhagen, Denmark, on 15 September. The data adds to the previously reported overall response rates and safety data on 27 June and 12 July.
Dr. Kristensen stated, The efficacy and safety data in TACTI-003 are very
encouraging and show the significant potential of this novel immunotherapy combination to fight difficult-to-treat head and neck squamous cell carcinomas. The clinically
meaningful improvement in responses for patients with high PD-L1 expression in the randomised portion of the trial, combined with the compelling response rates in patients with no PD-L1 expression, are a testament to the complementary nature of efti in combination with KEYTRUDA. I am particularly impressed that these higher response rates and clear increase in biological activity seen in the
efti arm do not come at the expense of durability of response or lead to an increased toxicity profile, which is often the case when combining therapies in the search for more efficacious treatments for cancer patients.
Dr. Fr d ric Triebel, CSO of Immutep, said Through multiple clinical trials, we see the promise of efti to not
only improve cancer patients clinical responses to immune checkpoint inhibitors, but also to expand patient populations who respond to them including patients with negative PD-L1 expression. Once again,
the TACTI-003 trial has reinforced efti s positive impact on both these fronts. We are excited to see efti in combination with KEYTRUDA now driving a 1.9-fold
increase in responses for head and neck cancer patients with high PD-L1 expression as compared to KEYTRUDA alone, and a statistically significant increase in absolute lymphocyte count in the treatment arm
showing efti s biological activity in a randomised setting.
Marc Voigt, CEO of Immutep, added As we move into the latter half of 2024, we will continue to
follow the data in TACTI-003 and start to engage with regulatory authorities regarding potential paths forward. We are certainly pleased with durability we are seeing, which is consistent with other trials in
which efti combined with KEYTRUDA achieves a high DOR, unlike many other therapeutic combinations. We are hopeful this positive duration of response continues and, as seen in first line non-small cell lung
cancer in the TACTI-002 trial evaluating efti in combination with KEYTRUDA, eventually contributes to an overall survival benefit for patients with first line head and neck cancer.
ESMO Congress 2024 Proffered Paper Oral Presentation
Title: Primary Results from TACTI-003: A Randomized Phase IIb Trial Comparing Eftilagimod Alpha (soluble LAG-3) Plus Pembrolizumab Versus Pembrolizumab Alone in First-Line Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma with CPS 1
Clinical Highlights from Randomised Cohort A in 1L HNSCC Patients with Any PD-L1 Expression (CPS
Efti leads to higher Objective Response Rates (ORR)
Efti maintains a high Duration of Response (DOR)
Efti increases Biological Activity
Efti continues to have favourable safety profile
Additionally, E+P drives a high ORR and Disease Control Rate (DCR) in 1L HNSCC patients regardless of PD-L1 expression. In Cohorts A and B together (N=89), E+P achieved a 33.7% ORR (34.8% including one partial response reported after data cut-off) including 31 patients
in Cohort B with negative PD-L1 (CPS <1). E+P also achieved a higher DCR compared to pembrolizumab monotherapy across all PD-L1 expression levels, with a consistent
increase from 58.1% DCR in CPS <1, to 69.0% DCR in CPS 1-19, to 75.9% DCR in CPS 20.
to the body of evidence that efti s activation of antigen-presenting cells provides a strong boost to the immune system, enhancing the potential of immune checkpoint inhibitors (ICI) such as KEYTRUDA. As the only MHC Class II agonist in
clinical development today, efti generates a broad anti-cancer immune response in combination with ICIs regardless of PD-L1 expression, including for patients with negative
PD-L1 expression, in a unique and safe manner across multiple different cancers.
The ESMO Proferred Paper Oral
Presentation slides are available on the Posters & Publications section of Immutep s website.
Immutep will continue to follow the maturing data from TACTI-003, with the most relevant endpoint of Overall Survival
expected in 2025, and engage with regulatory authorities regarding potential paths forward.
KEYTRUDA is a registered trademark of Merck
Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.
The Two ACTive Immunotherapies-003 (TACTI-003) trial is an ongoing
Phase IIb study (also known as KEYNOTE-C34) evaluating eftilagimod alpha (efti), Immutep s proprietary soluble LAG-3 protein and MHC Class II agonist, in
combination with MSD s (Merck & Co., Inc., Rahway, NJ, USA) anti-PD-1 therapy KEYTRUDA
(pembrolizumab) as first line treatment of recurrent or metastatic head and neck squamous cell carcinoma (HNSCC). The randomized Cohort A portion of the study is evaluating efti in combination with pembrolizumab as compared to pembrolizumab
monotherapy in patients with PD-L1 positive (Combined Positive Score [CPS] 1) tumours, whereas Cohort B is evaluating efti in combination with pembrolizumab in patients with PD-L1 negative tumours (CPS <1).
The primary endpoint of the study is Objective Response Rate of evaluable patients
according to RECIST 1.1. Secondary endpoints include Overall Survival, Objective Response Rate according to iRECIST, Progression Free Survival, and Duration of Response. For more information about the Phase IIb trial, visit clinicaltrials.gov
clinical-stage biotechnology company developing novel LAG-3 immunotherapy for cancer and autoimmune disease. We are pioneers in the understanding and advancement of therapeutics related to Lymphocyte
Activation Gene-3 (LAG-3), and our diversified product portfolio harnesses its unique 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.
Australian Investors/Media:
+61 (0)406 759 268; catherine.strong@sodali.com
Chris Basta, VP, Investor Relations and
Corporate Communications
+1 (631) 318 4000; chris.basta@immutep.com
This announcement was authorised for release by the Board of Immutep Limited.
Immutep Limited, Level 32, Australia Square, 264 George Street, Sydney NSW 2000, Australia