Definition

A humanized, hinge-stabilized immunoglobulin G4 (IgG4) monoclonal antibody directed against growth/differentiation factor 15 (GDF-15; macrophage inhibitory cytokine-1; MIC-1; non-steroidal anti-inflammatory drug-inducible gene-1; NAG-1; placental transforming growth factor-beta; pTGFB; prostate-derived factor; PDF; placental bone morphogenetic protein; PLAB), with potential antineoplastic activity. Upon administration, anti-GDF-15 monoclonal antibody CTL-002 specifically targets, binds to and inhibits the activity of GDF-15, which may include its inhibition of lymphocyte function-associated antigen 1 (LFA-1) activation on CD8+ T cells. This may restore immune cell infiltration into the tumor, leading to tumor cell killing and inhibition of tumor cell proliferation. GDF-15, a divergent member of the transforming growth factor-beta (TGF-beta) superfamily of cytokines, is upregulated in tissue injuries and also secreted by various tumors. It has been linked to immunosuppression in the tumor microenvironment (TME) and is associated with drug resistance and poor prognosis.