Xolair: which tox species, and why?

“Two pivotal repeated-dose toxicity studies were performed in Cynomolgus monkeys”

“The Cynomolgus monkey was chosen as model to predict human pharmacology and toxicology since omalizumab binds Cynomolgus and human IgE with similar affinity but does not bind non-primate IgE.”

“Rodent asthma models were not considered because of the species specificity of omalizumab and because there were no appropriate non-anaphylactogenic surrogate antibodies available for evaluation in rodent models.”

“Two pivotal repeated-dose toxicity studies were performed in Cynomolgus monkeys: a 4-week iv/sc study with a 4-week recovery period, dosing three times weekly in the range 0.1-5.0 mg/kg, and a 6- month iv/sc study”

“Male and female fertility, embryotoxicity/teratology, and late gestational/placental transfer were studied in Cynomolgus monkeys, since omalizumab would not bind to rodent/rabbit IgE”

“No carcinogenicity study with omalizumab was performed since omalizumab does not bind rodent IgE.”

“since omalizumab would not bind to rodent/rabbit IgE, and a non-anaphylactogenic anti-murine IgE Mab surrogate antibody was not available.”