No cytokine release in any of four in vitro assay formats
“All assays, conducted using appropriate positive and negative controls, did not indicate the potential for stimulation of UCB7665-induced cytokine release.”
TCR in human and cynomolgus tissues: generally similar staining patterns between species
“The staining patterns were generally similar between species; however, the study report did not specify whether specific binding was membranous or cytoplasmic.”
Infection risk from FcRn blockade reducing circulating IgG
“Infections were of special interest because Fc receptor inhibition results in a reduction of circulating IgG, which potentially increases the risk of infection.”
ADA in most monkeys; higher titers reduced exposure and IgG-lowering effect
“In both studies, anti-drug antibody (ADA) development in most animals was observed. The ADA response was generally correlated with reduced pharmacodynamic (PD) effect (i.e., a reduction in IgG levels) and reduced exposure in animals with higher ADA titers.”
ADA 37% (49/133) after one 6-week cycle; neutralizing 21% (28/133)
“The anti-drug antibody (ADA) incidence from Study 1 (MG0003) was 37% (49/133) at the end of the observation period after one treatment cycle of 6-week dosing. The incidence of neutralizing antibodies was 21% (28/133).”
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