Effectiveness of the vaccination of infants against Haemophilus influenzae B (HiB) and tetanus toxin does not appear to be affected by exposure to biologic therapy taken by mothers with inflammatory bowel disorders (IBD) during pregnancy, as measured by antibody titers, new research shows.
Beaulieu et al. analyzed 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 between 2007 and 2016.
The researchers assessed serum titers of antibodies to HiB and tetanus toxin from infants who were at least 7 months old and whose mothers vaccinated their children (n=179 mothers). In addition, the researchers assayed umbilical cord blood samples from 33 infants to assess the concentration of biologic agents. Then, vaccination response of 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) was compared to that of infants born to unexposed mothers.
The researchers found no significant difference in proportions of infants with protective antibody titers against HiB born to exposed mothers vs unexposed mothers (n=42 and n=8 respectively, P=0.41).
In addition, there was no difference in the proportion of infants with protective antibody titers to tetanus toxoid born to exposed vs. unexposed mothers (80% and 75% respectively, P=0.66).
Similarly, the median concentration of infliximab in cord blood did not differ significantly between infants with vs. without protective antibody titers to HiB (P=0.30) or tetanus toxoid (P=0.93). Seven of 40 infants who received rotavirus vaccine and whose mothers had been exposed to biologic therapies experienced mild reactions.
The researchers undertook the study to extend previous research demonstrating that in women with IBD, exposure to immunomodulator or biologic therapy has not been associated with adverse events during pregnancy or outcomes of newborns. The current study extended the previous investigation by exploring whether exposure of patients to these agents during pregnancy affects serologic responses to vaccines in newborns.
Beaulieu DB, Ananthakrishnan AN, Martin C, et al. Use of Biologic Therapy by Pregnant Women with Inflammatory Bowel Disease Does Not Affect Infant Response to Vaccines. Clin Gastroenterol Hepatol. 2017 Sep 1. [Epub ahead of print]