Immutep Presents Data from Safety Lead-in Phase of AIPAC-003 at ESMO Breast 2024

Media Release

• Confirmed complete response in a patient with metastatic breast cancer refractory to several lines of therapy achieved during combination treatment with 90mg efti and paclitaxel
• Ongoing complete response has been maintained since the patient started treatment with efti monotherapy
• Efti + paclitaxel combination continues to be well tolerated with a favourable safety profile
• First-ever 90mg dosing leads to higher maximum concentration of efti, as well as pharmacologically active level up to 96 hours after administration
• Data from randomized Phase II portion of study expected in CY2024
  
  

SYDNEY, AUSTRALIA, May 15, 2024 (GLOBE NEWSWIRE) -- 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 encouraging efficacy, safety, and pharmacodynamic data from the safety lead-in of the AIPAC-003 Phase II/III trial presented at the European Society for Medical Oncology (ESMO) Breast Cancer 2024 Congress. This lead-in represents the first ever 90mg dosing of eftilagimod alpha (“efti”), a soluble LAG-3 protein and MHC Class II agonist, given in combination with weekly paclitaxel.

Efficacy
The poster titled “Testing a higher dose (90 mg s.c.) of eftilagimod alpha, a soluble LAG-3 protein, in metastatic breast cancer patients receiving weekly paclitaxel in AIPAC-003” details positive results in six metastatic breast cancer (MBC) patients, who exhausted endocrine therapy including cyclin-dependent kinase 4/6 (CDK4/6) inhibitors. The data shows a confirmed 50% overall response rate, including one complete response and two partial responses, and a 100% disease control rate, with three patients having stable disease as best overall response per RECIST 1.1.

Complete Response Patient Case Study
The patient with a confirmed complete response (CR) was diagnosed with triple-negative breast carcinoma (TNBC) in 2019 and has failed multiple lines of therapy including a CDK 4/6 inhibitor for ER+/PR+ metastasis. During the immuno-oncology (IO)-chemotherapy treatment of efti and paclitaxel, this patient achieved a partial response (PR) that subsequently turned into a CR. This patient’s ongoing CR has been maintained since stopping paclitaxel and being treated with efti monotherapy.