Investigation of maternal and fetal exposure to an IgG2 monoclonal antibody following biweekly intravaginal administration to cynomolgus monkeys throughout pregnancy

•Prior to gd119, all maternal IgG2X plasma concentrations were BLQ (<25ng/mL).•In 3/5 monkeys, maternal IgG2X remained BLQ throughout pregnancy.•In 2/5 monkeys, maternal IgG2X reached ∼0.01% IvG dose after gd119 and 133.•IgG2X was BLQ (<25ng/mL) in all fetal plasma samples.•Male-mediated monoclonal antibody drug transfer via semen does not present a health risk in humans.