Prima BioMed claims development of first LAG-3 agonist antibody

Australian biotech firm Prima BioMed (ASX: PRR) says it has developed a new early-stage product candidate, a humanized IgG4 monoclonal antibody to be known as IMP761.This antibody, developed at the company's laboratory in Châtenay-Malabry south of Paris, France, is believed to be the first agonist antibody of LAG-3.

The IMP761 agonist antibody is an exciting new addition to the Prima pipeline of product candidates, the company states. It is mechanistically distinct from any of the known LAG-3 antibodies. Prima continues to lead the way in researching and developing novel LAG-3 targeting technologies. A new patent has been filed to provide protection for this antibody.

Dr Frédéric Triebel, Prima’s chief medical officer, said: "Even though IMP761 is an early stage product, we are very excited to have developed what we believe is the first ever agonist of LAG-3. Until now, therapeutic antibodies with agonistic properties have not been described for any of the three major immune checkpoints, CTLA-4, PD-1 or LAG-3. IMP761 promises the first opportunity for fine tuning of the immune response to an immune checkpoint target. This singular biological activity of IMP761 could benefit sufferers of certain autoimmune diseases by temporarily switching off activated LAG-3+T cells that are damaging tissue or creating inflammatory responses."