Animal experiment:

Rats[1] Rats are orally pre-dosed with RIP2 kinase inhibitor 1, at a dose of 2 mg/kg (8 rats) and with Prednisolone (8 rats, used as a positive control), followed by dosing with L18-MDP (50 μg/rat) 0.25 h/min after pre-dosing. Combined cytokine levels (IL8, TNFa, IL6 and IL-Ιβ) in whole blood samples taken from the rats in this study are measured using an antibody based detection. The combined cytokine response is calculated as the averaged response for the 4 cytokines measured relative to the response observed in the vehicle-treated mice, and are depicted as the mean±standard error of the mean (n=8 rats/group).

RIP2 kinase inhibitor 1 is a receptor interacting protein-2 (RIP2) kinase inhibitor extracted from patent WO/2014043446 A1, compound example 1.

RIP2 kinase inhibitor 1 is a novel prodrug of a quinazolyl amine that inhibits RIP2 kinase. Receptor interacting protein-2 (RIP2) kinase, which is also referred to as CARD3, RICK, CARDIAK, or RIPK2, is a TKL family serine/threonine protein kinase involved in innate immune signaling. RIP2 kinase is composed of an N-terminal kinase domain and a C-terminal caspase-recruitment domain (CARD) linked via an intermediate (IM) region. The CARD domain of RIP2 kinase mediates interaction with other CARD-containing proteins, such as NODI and NOD2. NODI and NOD2 are cytoplasmic receptors which play a key role in innate immune surveillance. They recognize both gram positive and gram negative bacterial pathogens and are activated by specific peptidoglycan motifs, diaminopimelic acid (i.e., DAP) and muramyl dipeptide[1].

[1]. Linda N. Casillas, et al. Prodrugs of amino quinazoline kinase inhibitor. PCT Int. Appl. (2014), WO 2014043446 A1 20140320.