Anti-drug antibodies in 83% (25 mg/kg) and 58% (50 mg/kg) of cynomolgus monkeys
“However, throughout the study, antibodies against ibalizumab were observed in 83% (10/12) and 58% (7/12) of the animals at the low and high dose (25 and 50 mg/kg), respectively.”
CD4 binding: reversible CD4+ T- and B-cell lymphocytopenia and immunosuppression in infants exposed in utero
“Based on animal data, ibalizumab-uiyk use during pregnancy may cause reversible immunosuppression (CD4+ T cell and B cell lymphocytopenia) in infants exposed to ibalizumab-uiyk in utero.”
In vitro whole-blood cytokine release far below alemtuzumab/TGN1412 controls; no effects on monkey TDAR, lymphocyte subsets or serum cytokines; ADA in some monkeys