Arginase 1: IO112

The endogenous immunoregulatory enzyme arginase contributes to immune regulation by catabolizing and limiting the availability of the amino acid arginine, which is essential for immune effector cell survival and growth. Arginase overproduction by immune suppressive cells like myeloid derived suppressor cells and tolerogenic dendritic cells is a well-documented tumor escape mechanism. Increased levels of arginine have been detected on tumor and immune cells in a number of solid tumor types. 

Our fully owned IO112 program is a first-in-class, immune modulatory vaccine containing a single arginase derived peptide designed to engage and activate arginase specific human anti-regulatory T-cells.

IO112 is being tested in a single clinical trial:

  • A single arm phase I trial in patients with arginase-positive solid tumors (NCT03689192).


Frequent adaptive immune responses against arginase-1
OncoImmunology, December 2017