Eculizumab in pregnancy: a narrative overview.

Pregnancy can be a dangerous trigger for patients with paroxysmal nocturnal hemoglobinuria (PNH), atypical hemolytic uremic syndrome (aHUS), or hemolysis, elevated liver enzymes and low platelet (HELLP) syndrome. Due to the possibility of several serious complications, pregnancy is somewhat discouraged in the presence of the above diseases. Eculizumab is a humanized antibody that may dramatically change the clinical course of PNH, aHUS and HELLP syndrome. However, data on the safety of eculizumab in pregnancy are scarce. In this narrative overview, we summarize current evidence on the use of eculizumab during pregnancy in women with PNH, aHUS and HELLP syndrome. Eculizumab is not present in breast milk, and the levels observed in umbilical cord blood samples are not sufficient to affect the concentrations of complement in newborns. Therefore, eculizumab may be regarded as safe in pregnancy. Nonetheless, given that data on eculizumab in pregnancy are limited, it is not possible to completely exclude risks for both mother and fetus in treating PNH, aHUS and HELLP syndrome.