Immutep Doses First Participant in Phase I Study of IMP761, a Novel Agonist LAG-3 Antibody

Immutep Limited, a clinical-stage biotechnology company specializing in the development of novel LAG-3 immunotherapies for cancer and autoimmune diseases, has announced the successful administration of the first dose in the initial human Phase I trial of IMP761. The trial involves a unique LAG-3 antibody designed to enhance the "brake" function of LAG-3 on T cells, thereby aiming to restore immune system balance and address the root causes of various autoimmune diseases.

The Phase I study is a placebo-controlled, double-blind trial with both single and multiple ascending doses. Conducted by the Centre for Human Drug Research (CHDR) in Leiden, Netherlands, it aims to enroll 49 healthy volunteers. The primary objectives are to assess the safety, pharmacokinetics (PK), and pharmacodynamics (PD) of IMP761. The study leverages CHDR's unique keyhole limpet haemocyanin (KLH) challenge model, which is instrumental in evaluating the pharmacodynamic activity of IMP761 at early clinical development stages.

Initial safety data from the study is expected by the end of the year, while detailed PK and PD data are anticipated in the first half of 2025. Preclinical studies of IMP761 have shown promising results, including a significant reduction in inflammatory cytokines and effective suppression of antigen-specific T cell-mediated immune responses. This suggests that IMP761 could be a potential therapeutic option for autoimmune diseases such as rheumatoid arthritis, Type 1 diabetes, and multiple sclerosis.

IMP761 is a pioneering immunosuppressive LAG-3 agonist antibody. The primary mechanism involves silencing autoimmune memory T cells at disease sites, thereby restoring the immune system's balance. Published studies in the Journal of Immunology have demonstrated that IMP761 can inhibit peptide-induced T cell proliferation and activation of human primary T cells. Moreover, it has shown effectiveness in mitigating antigen-specific delayed-type hypersensitivity reactions. Additional preclinical research published in Pediatric Research on oligoarticular juvenile idiopathic arthritis (o-JIA) indicates that IMP761 significantly reduces a broad spectrum of effector cytokines within 48 hours. The study also revealed that children with o-JIA have an imbalanced LAG-3 metabolism, suggesting they could benefit from the agonistic activity of LAG-3.

Immutep is recognized for its pioneering work in understanding and advancing Lymphocyte Activation Gene-3 (LAG-3) therapeutics. The company's diversified product portfolio takes advantage of LAG-3's unique ability to either stimulate or suppress the immune response, depending on the therapeutic need. Immutep aims to leverage its expertise to offer innovative treatment options for patients and maximize value for its shareholders.