Beaulieu DB, et al. – This research aspired to examine whether exposure of patients to immunomodulator or biologic therapy during pregnancy influenced serologic responses to vaccines in newborns. Based on antibody titers measured after months of age, vaccination of infants against Haemophilus influenzae B (HiB) and tetanus toxin did not appear to be affected by in utero exposure to biologic therapy.

• From 2007 - 2016, the clinicians gathered data from the Pregnancy in IBD and Neonatal Outcomes registry, which records outcomes of pregnant women with diagnosis of IBD receiving care at multiple centers in the United States.
• From July 2013 through October 2016, Serum samples collected from infants at least 7 months of were examined for titers of antibodies to Haemophilus influenzae B (HiB) or tetanus toxin; mothers completed a survey of vaccine practices and outcomes.
• They assayed umbilical cord blood samples from 33 infants for concentration of biologic agents.
• They compared vaccination response between infants born to mothers exposed to biologic therapy (infliximab, adalimumab, certolizumab pegol, golimumab, natalizumab, vedolizumab, or ustekinumab-either as a single agent or in combination with an immunomodulator at any time between conception and delivery) and infants born to unexposed mothers.

• The vaccine survey was completed by 179 women (26 biologic unexposed, 153 biologic exposed).
• There was no significant difference in proportions of infants with protective antibody titers against Hib born to exposed mothers (n=42) (71%) compared to unexposed mothers (n=8) (50%) (P=.41).
• Furthermore, no difference was found in the proportion of infants with protective antibody titers to tetanus toxoid born to exposed mothers (80%) compared to unexposed mothers (75%) (P=.66).
• In this study, the median concentration of infliximab in cord blood did not differ significantly between infants with vs without protective antibody titers to HiB (P=.30) or tetanus toxoid (P=.93).
• The clinicians observed mild reactions in 7 out of 40 infants who received rotavirus vaccine and whose mothers had been exposed to biologic therapies.