Omalizumab during pregnancy does not amplify risk of major congenital anomalies

Omalizumab does not seem to increase the risk of major congenital anomalies among pregnant women and their children, a recent study has shown.

Drawing from the EXPECT* study, researchers enrolled 230 asthmatic women who had received omalizumab treatment during pregnancy. A parallel group of 1,153 disease-matched women who had not been given the investigational treatment was also included. Pregnancy and infant outcomes were compared between groups.

Women were enrolled into the EXPECT study at a median gestational age of 11.0 weeks, and they were exposed to omalizumab for a median of 8.8 months of pregnancy. More than half (52.8 percent) received the medication every 2 weeks.

The rate of live births was comparable between the omalizumab-treated and nontreated cohorts (99.1 percent vs 99.3 percent), as was the mean birth weight of singleton, live-born infants (3.2 vs 3.2 kg). The prevalence of low birthweight was slightly higher in the EXPECT cohort (13.7 percent vs 9.8 percent).

Eighteen of the 223 infants born to women in the EXPECT cohort had major congenital anomalies, yielding a prevalence rate of 8.1 percent. There were more cases in the nontreated comparator cohort (n=102 of 1,124), though with a similar rate of occurrence (8.9 percent).

In the EXPECT cohort, major congenital anomalies occurred most frequently in the eye-ear-face-neck system (2.2 percent); all of these cases were of torticollis. Other common congenital problems were hydronephrosis (1.3 percent) and hypospadias (0.9 percent).

*The Observational Study of the Use and Safety of Xolair