Immutep's IMP761 Phase I Trial Enters Dose Escalation Stage

Immutep Limited, a clinical-stage biotechnology company, has made substantial progress in its Phase I clinical trial for IMP761, a novel LAG-3 immunotherapy. The company, listed on both ASX and NASDAQ, focuses on developing innovative treatments for cancer and autoimmune diseases. Recently, Immutep announced that the first part of the trial (Part A), which involves a single dose administration in a placebo-controlled, double-blind study, has been fully recruited and completed without any safety issues. This significant milestone brings the trial one step closer to evaluating the drug's efficacy and safety comprehensively.

The trial is being conducted at the Centre for Human Drug Research (CHDR) in Leiden, the Netherlands. In the next phase, known as Part B, the trial will escalate the dosing of IMP761, starting from 0.03 mg/kg and potentially reaching up to 0.90 mg/kg. Both safety and pharmacokinetic/pharmacodynamic (PK/PD) modeling will be meticulously assessed in this phase, involving 30 healthy volunteers. If no safety concerns arise, the trial will advance to Part C, which will involve multiple ascending doses of IMP761 in 14 subjects, with further PK evaluations.

A unique aspect of this Phase I study is the use of CHDR's keyhole limpet haemocyanin (KLH) challenge model in Parts B and C. This model is integral in assessing the pharmacodynamic activity of IMP761 early in its clinical development. Immutep anticipates that the initial safety data from this trial will be available before the end of the year, with PK/PD relationship assessments expected in the first half of 2025.

IMP761 is described as a first-in-class immunosuppressive LAG-3 agonist antibody, which holds promise in targeting the underlying causes of various autoimmune diseases. It operates by specifically silencing autoimmune memory T cells at disease sites, hence restoring balance to the immune system. Published research in the Journal of Immunology has highlighted the efficacy of IMP761 in pre-clinical in vivo and in vitro studies. These studies demonstrated that IMP761 inhibits peptide-induced T cell proliferation, activation of human primary T cells, and an antigen-specific delayed-type hypersensitivity (DTH) reaction. Moreover, additional preclinical data published in Pediatric Research on oligoarticular juvenile idiopathic arthritis (o-JIA) revealed that IMP761 significantly reduced a broad spectrum of effector cytokines within just 48 hours. The study also suggested that children with o-JIA, who have a skewed LAG-3 metabolism, could benefit from the agonistic LAG-3 activity provided by IMP761.

Immutep is recognized for its pioneering efforts in understanding and advancing therapeutics related to Lymphocyte Activation Gene-3 (LAG-3). The company’s diverse product portfolio leverages the unique capacity of LAG-3 to modulate the immune response, either by stimulation or suppression. Immutep is committed to utilizing its expertise to develop groundbreaking treatment options for patients in need, thereby maximizing value for its shareholders. The company continues to forge ahead with its innovative research and clinical trials, aiming to make significant strides in the treatment of cancer and autoimmune diseases.