Ravulizumab exposure in early pregnancy.

Before complement inhibitors were available, pregnancy in women with paroxysmal nocturnal hemoglobinuria (PNH) was associated with considerable mortality, mainly due to thromboembolism. The complement-C5 inhibitor eculizumab has decreased this risk and improved pregnancy outcomes in women with PNH. Eculizumab has now largely been replaced by the longer acting ravulizumab in non-pregnant PNH patients. We report on ravulizumab exposure in early pregnancy in a 33 years-old PNH patient. She had become pregnant while on ravulizumab therapy and was switched to eculizumab in gestational week 11. Thus, exposure to ravulizumab occurred in a sensitive period of embryogenesis. Pregnancy was uneventful with a normal organ scan, followed by caesarean section. The male infant had an Apgar score of 9/9/10, without signs of perinatal morbidity. Birth weight was 3580 g, body length 53 cm, and head circumference 35.5 cm. The infant was fully breastfed and appeared well when being discharged home on the fourth day of life. Together, the use of ravulizumab during pregnancy in our patient was not harmful for the child. More data are needed to determine whether ravulizumab is indeed a safe treatment option for PNH in pregnancy.