There is no evidence that eculizumab use has caused harm to the new-born, though most of the data is observational, from eculizumab use in patients with paroxysmal nocturnal haemoglobinuria (PNH). The largest reported experience of eculizumab use during and after pregnancy was in 75 pregnancies in 61 women. Twenty cord-blood samples were examined for the presence of eculizumab; the drug was detected in 7 of the samples. In another study in which eculizumab was detected in cord blood, there was normal complement activity in 2 new-borns suggesting that even if eculizumab crosses the placenta, the level is not high enough to affect complement activation.
In the PNH study, a total of 25 babies were breast-fed, and in 10 of these cases, breast milk was examined for the presence of eculizumab; the drug was not detected in any of the 10 breast-milk samples. These findings suggested that the drug is not excreted into breast milk in measurable amounts and that breast-feeding by patients receiving eculizumab is likely to be safe.