Posted: 12 March 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 safety and initial efficacy data from the first ever 90mg dosing of eftilagimod alpha (efti) in combination with weekly paclitaxel in patients from the safety lead-in (N=6) of the AIPAC-003 Phase II/III trial.
Updated safety data from patients with HR-positive/HER2-negative/low metastatic breast cancer (MBC) treated with this innovative immuno-oncology (IO)-chemotherapy combination reveal no treatment-emergent serious adverse events. Additionally, all treatment-emergent adverse events during the safety observation period to date have been of mild severity.
Initial efficacy reports show these six MBC patients, who exhausted all endocrine therapy including cyclin-dependent kinase 4/6 (CDK4/6) inhibitors, exhibited encouraging results achieving a 50% overall response rate, including one complete response and two partial responses, and a 100% disease control rate overall with the remaining three patients having stable disease as best response.
Acknowledging the early nature of these results, efti with paclitaxel historically has shown a dose-dependent effect in MBC and has in some cases also led to stable disease patients becoming partial responders after six months. The biologically active 30mg efti dose, previously the highest dose of efti ever tested, has demonstrated a stronger immune response and greater efficacy than lower dosing levels (1mg, 6mg) in multiple clinical trials.
The ongoing randomized Phase II portion of the trial, which will include up to 58 evaluable patients, is focused on whether 90mg efti dosing is safe and more efficacious than 30mg dosing. This portion of the trial has enrolled 23 patients to date. Importantly, the determination of the optimal biological dose in AIPAC-003 is directly tied to the FDA’s Project Optimus initiative and is relevant for the entire efti program.
