RIP2 Kinase Inhibitor 4 (Compound 20) utilizes a novel inhibitor of apoptosis (IAP) binder. RIP2 Kinase Inhibitor 4 possess comparatively reduced binding potency at both cIAP1 and XIAP BIR3 domains and increased potency at the XIAP BIR2 domain[1]. RIP2 Kinase Inhibitor 4 (Compound 20) recruits the IAP E3 ligases and shows markedly reduced inhibition of muramyl dipeptide (MDP)-stimulated TNFα production in human peripheral blood mononuclear cells (PBMCs) (pIC 50 of 9.3)[1].

The initial in vivo assessment of RIP2 Kinase Inhibitor 4 (Compound 20) in rats dosed at 0.5 mg/kg SC demonstrated high levels of RIPK2 degradation and inhibition of MDP-stimulated TNFα release at the final 48 h time point[1].