Immutep reports promising Phase I results for IMP761, a novel LAG-3 agonist antibody demonstrating significant T cell inhibition and a clean safety profile, advancing hopes for new autoimmune disease treatments.
- IMP761 achieves 80% T cell suppression at 0.9 mg/kg dose
- No treatment-related adverse events observed in healthy volunteers
- Phase I dose escalation continues with higher doses planned
- Targeting major autoimmune diseases including rheumatoid arthritis and type 1 diabetes
- Additional Phase I data expected in second half of 2025
Early Clinical Promise for IMP761
Immutep Limited (ASX, IMM) has unveiled encouraging initial data from its Phase I clinical trial of IMP761, a first-in-class LAG-3 agonist antibody designed to treat autoimmune diseases. The placebo-controlled, double-blind study conducted in healthy volunteers has demonstrated substantial suppression of T cell activity, up to 80% inhibition at the 0.9 mg/kg dose, without any treatment-related adverse events. This early pharmacological success highlights IMP761’s potential as a targeted immunotherapy that could modulate the immune system with fewer side effects than current treatments.
A Novel Approach to Autoimmune Disorders
Autoimmune diseases such as rheumatoid arthritis, type 1 diabetes, and multiple sclerosis affect millions worldwide and represent multi-billion dollar markets. IMP761 works by enhancing the immune checkpoint LAG-3, effectively applying a “brake” on dysregulated memory T cells that attack the body’s own tissues. This mechanism aims to restore immune balance rather than broadly suppress immune function, which could translate into improved safety and efficacy profiles compared to existing therapies.
Dose Escalation and Future Data
Following the positive results at 0.9 mg/kg, Immutep is advancing the trial with higher single ascending doses of 2.5, 7, and 14 mg/kg. The study is being conducted at the Centre for Human Drug Research in the Netherlands, employing a neoantigen rechallenge model to assess pharmacodynamic effects. Additional data from these dose levels are anticipated in the second half of 2025, which will be critical to confirming IMP761’s safety and therapeutic potential.
Strategic Implications for Immutep
As a late-stage biotech focused on immunotherapies, Immutep’s advancement of IMP761 complements its broader LAG-3 portfolio targeting both cancer and autoimmune diseases. The company’s Chief Scientific Officer, Dr. Frédéric Triebel, emphasized the unique specificity of LAG-3 expression at sites of chronic inflammation, suggesting IMP761 could offer a more precise treatment option. If successful, this could position Immutep as a leader in a novel class of immunomodulatory therapies with significant market potential.
Looking Ahead
While these early findings are promising, IMP761 remains in the initial stages of clinical development. The upcoming dose escalation data will be pivotal in determining whether the antibody’s efficacy and safety profile hold at higher doses and in patient populations. Investors and industry watchers will be keenly observing how Immutep navigates these next steps amid a competitive landscape of autoimmune disease treatments.
Bottom Line?
IMP761’s early success sets the stage for a potentially transformative autoimmune therapy, but the real test lies ahead in higher dose and patient trials.
Questions in the middle?
- Will higher doses of IMP761 maintain safety while enhancing efficacy?
- How will IMP761 perform in patients with active autoimmune diseases versus healthy volunteers?
- What is the competitive landscape for LAG-3 agonists and how might Immutep differentiate?