Immutep Limited announced it has received regulatory clearance from the ethics and competent authority in the Netherlands to initiate the first-in-human Phase I study of IMP761. IMP761 is the world's first therapeutic LAG-3 agonist antibody and as such is uniquely positioned in the treatment landscape for autoimmune diseases. The immune checkpoint LAG-3 has been identified as a promising target for agonist immunotherapy to treat rheumatoid arthritis, Type 1 diabetes, and multiple sclerosis, among other autoimmune diseases.

IMP761 is designed to restore balance to the immune system by enhancing the "brake" function of LAG-3 to silence unregulated self-antigen-specific memory T cells. These T cells accumulate at disease sites and are the underlying cause of many autoimmune diseases. In preclinical studies, the agonistic LAG-3 antibody IMP761 has shown, both in vitro and in vivo, to be highly effective in suppressing antigen-specific T cell-mediated immune responses and driving a meaningful decrease in inflammatory cytokines.

It is exciting to see IMP761 move into the clinical setting to evaluate the potential of this new immunotherapy to address autoimmune diseases. As published in the Journal of Immunology, encouraging pre-clinical in vivo and in vitro studies show IMP761 inhibits peptide-induced T cell proliferation, activation of human primary T cells, and an antigen-specific delayed-type hypersensitivity (DTH) reaction. Additional preclinical data in oligoarticular juvenile idiopathic arthritis (o-JIA) published in Pediatric Research details how IMP761 led to a decrease in a broad spectrum of effector cytokines in just 48 hours.

This study also showed children with o-JIA have a skewed LAG-3 metabolism and suggested they can benefit from agonistic LAG-3 activity.