Additionally, Tumour Growth Kinetics (TGK) analysis looking at the difference of the sum of the largest diameters of target lesions in the pre- and post-baseline setting was performed on patients with data available on the same lesions from prior failed therapy and post-baseline (N=24). 83.3% of patients showed shrinkage (33%) or deceleration of tumour growth (50%). Notably, 36%, 39%, and 16.7% of patients had a PD-L1 Tumour Proportion Score (TPS) of <1%, 1-49%, and >50%, respectively, and 8.3% of patients were not evaluable for PD-L1 expression.
Efti plus pembrolizumab had an ORR of 8.3%, a DCR of 33%, and a 6-month PFS rate of 25% in the all-comerPD-L1 patient population, with most of these PD-X refractory patients (75%) having negative or low PD-L1 expression. The ORR, PFS, and OS were more pronounced in patients with high PD-L1 expression (N=6) or who were secondary resistant (N=25). For patients with ≥50% PD-L1 TPS expression, mOS was not yet reached, ORR was 33.3%, and 6-month PFS was 50%. Efti plus pembrolizumab was well tolerated without any new safety signals, and there was no treatment discontinuation due to adverse reactions.
Immutep CSO and CMO, Dr Frederic Triebel, noted: “The maturation of data across all three indications in the all-comer TACTI-002 trial, namely 1st line non-small cell lung cancer, 2nd line head and neck cancer, and 2nd line PD-X refractory non-small cell lung cancer, has continued to strengthen our belief that combining immunotherapies that harness the power of both innate and adaptive immunity may be very effective in fighting cancer. Efti’s unique targeting and activation of antigen-presenting cells has shown a promising benefit with checkpoint inhibitors that target T cells, and we believe the combination of efti and pembrolizumab has significant potential to safely improve outcomes for cancer patients.”
Immutep CEO, Marc Voigt, concluded, “These encouraging results and overall survival trends in patients refractory to PD-1/PD-L1 containing therapy, which have confirmed progression via two consecutive scans, offers a potential therapeutic pathway for many in dire need of new options. As we assess this potential, we continue to focus our late-stage clinical development of efti in combination with anti-PD-1 therapy in 1st line non-small cell lung cancer and 1st line head and neck cancer and look forward to providing more details on both as the year progresses.”
The Mini Oral presentation will be available on the Posters & Publications section of Immutep’s website.
About Eftilagimod Alpha (Efti)
Efti is Immutep’s proprietary soluble LAG-3 clinical stage candidate that is a first-in-class antigen presenting cell (APC) activator that stimulates both innate and adaptive immunity for the treatment of cancer. Efti binds to and activates antigen-presenting cells via MHC II molecules leading to expansion and proliferation of CD8+ (cytotoxic) T cells, CD4+ (helper) T cells, dendritic cells, NK cells, and monocytes. It also upregulates the expression of key biological molecules like IFN-g and CXCL10 that further boost the immune system’s ability to fight cancer.
Efti is under evaluation for a variety of solid tumours including non-small cell lung cancer (NSCLC), head and neck squamous cell carcinoma (HNSCC), and metastatic breast cancer. Its favourable safety profile enables various combinations, including with anti-PD-[L]1 immunotherapy and/or chemotherapy. Efti has received Fast Track Designation in 1st line HNSCC and in 1st line NSCLC from the United States Food and Drug Administration (FDA).
