“Toxicology studies with tildrakizumab were conducted in cynomolgus monkeys which were shown to be a relevant species, based on the binding of tildrakizumab to cynomolgus IL-23p19.”
98% IL-23p19 sequence homology and high-affinity binding in cynomolgus monkey; no binding to mouse IL-23p19
“Comparison of the amino acid sequences of IL-23p19 between human and various preclinical species revealed that cynomolgus monkeys had a 98% homology to humans.”
No surrogate in toxicology; the clinical antibody was tested in cynomolgus monkey (mouse surrogate SCH 900598 used for pharmacology)
“Due to the lack of cross-reactivity with mouse IL-23p19 and in order to test the potency efficacy in vivo a surrogate antibody, SCH 900598, was generated against the mouse IL-23p19.”