Guselkumab is a recombinant human IgG1 monoclonal antibody against the IL-23p19 subunit. Guselkumab binds to human and cynomolgus monkey IL-23 with Kd values of 3.3 and 1.9 pmol/L, respectively. Guselkumab inhibits production of cytokines lying downstream of the IL-23 signaling pathway and can be used for psoriatic arthritis research[1].

Guselkumab inhibits IL-23 (0.5 or 1 ng/mL)-mediated production of Th17 cytokines IL17A, IL-17F, and IL-22 in mouse splenocyteswith IC50 ranging 0.016-0.080 nM. And, it inhibits IL-23 (10 or 100 ng/mL)-mediated production of IL-10 in human NKL cells. Guselkumab has no effect on IL-12 (0.1 ng/mL)-mediated production of interferon γ (IFNγ) in NK92MI cells. [1].Guselkumab combines with IBI112 blocks IL-23-induced STAT3 phosphorylation, and Guselkumab blocks IL-23-induced STAT3 phosphorylation with an IC50 value of 102.1100±2.0053 nM[2].. Guselkumab blocks hIL-23-induced mIL-17 production in a dose-dependent manner, exhibiting an IC50 of 4.9743 ±1.2847 nM. In another experiment, Guselkumab also blocks IL-17F production in cynomolgus monkeys with an IC50 of 16.7950 nM[2].

[1]. International non-proprietary name: guselkumab Procedure No. EMEA/H/C/004271/0000par-public-assessment-report_en.pdf
[2]. Li Li, et al. IBI112, a selective anti-IL23p19 monoclonal antibody, displays high efficacy in IL-23-induced psoriasiform dermatitis. Int Immunopharmacol