Naive and allergen-challenged cynomolgus monkeys: eosinophil depletion in blood, bone marrow and BAL fluid
“In in vivo pharmacology studies, benralizumab, when given to naive or allergen-challenged cynomolgus monkeys, demonstrated rapid and pronounced reduction of eosinophils in blood, bone marrow and bronchoalveolar lavage fluid, demonstrating its pharmacological activity in vivo in this species.”
Binds human and cynomolgus IL-5Rα (KD 11 and 42 pM) but not murine IL-5Rα
“Benralizumab binds to human and cynomolgus monkey IL-5Rα with KD values of 11 and 42 pM, respectively (as measured by BIAcore). Benralizumab did not cross-react with murine IL-5Rα.”
✓ VerifiedFDA pharmacology/toxicology review, p. 38Source ↗
Reviewer's view of the efficacy data
EMA: monkey data sufficiently supported the eosinophil-reduction hypothesis for clinical testing; some non-responding individuals unexplained
“The reasons for these instances of difference are not understood. However, the results suggest that the hypothesis, that reducing eosinophilic cell infiltration in the lungs could improve lung function in an asthma challenge, was supported sufficiently to support clinical testing in patients with asthma.”