Hamster and mouse C. difficile infection models with actoxumab+bezlotoxumab
“Preclinical in vivo efficacy of actoxumab+bezlotoxumab was evaluated in the Golden Syrian hamster model of infection (at doses of 0.5 to 50 mg/Kg) and in the mouse CDI model (at doses of 2, 5, 10 and 50 mg/Kg).”
Infection models available; tested with actoxumab because bezlotoxumab alone has poor efficacy in rodent models
“The protective effects of bezlotoxumab have been shown in vitro in TcdB neutralization assays, and in nonclinical studies in mouse and hamster models of CDI (in combination with actoxumab, since bezlotoxumab alone has poor efficacy in rodent models).”
EMA: limitation that preclinical efficacy rests on the actoxumab combination, not bezlotoxumab alone
“Although clinical study results suggest that neutralization of toxin B is sufficient to reduce the risk of recurrent disease in humans, the preclinical efficacy data rely on the combination of actoxumab and bezlotoxumab instead of bezlotoxumab alone.”