New data from the Omalizumab pregnancy registry

Published Online: October 17, 2014

Asthma is one of the most common potentially serious medical problems to complicate pregnancy, and asthma may not only affect the mother’s quality of life, but also the pregnancy itself.  Uncontrolled asthma has been shown to lead to poor pregnancy outcomes.  A variety of medical asthma therapies are available; however, there is a lack of adequate safety information relative to use in pregnancy for many of these medications. Omalizumab, a recombinant monoclonal anti-immunoglobulin E (IgE) antibody, is licensed in the United States as an add-on therapy for the treatment of patients (aged ≥12 years) with moderate-to-severe persistent allergic asthma. Importantly, the safety of Omalizumab exposure during pregnancy in humans has not been previously evaluated.  Now in a study from The Journal of Allergy and Clinical Immunology, J. Namazy and colleagues present the first results from, EXPECT, the Omalizumab pregnancy registry.

EXPECT, a prospective, observational study, was designed to evaluate negative health outcomes in pregnant women and their infants. Pregnant women exposed to Omalizumab during pregnancy were eligible to participate. Data were collected at enrollment, during each trimester, at pregnancy outcome, and every 6 months up to 18 months post delivery for live born infants.

The authors report outcomes from 169 pregnancies and found the incidence of congenital malformations is no higher than rates found in the general population with asthma. The proportion of other negative pregnancy outcomes such as premature birth, low birth weight, and small size for gestational age were not inconsistent with findings from other studies in this asthma population.

The safety information for Omalizumab during pregnancy has not, until now, been reported. These interim study results do not suggest any new safety signals and must be weighed against the risk of uncontrolled asthma. The registry remains open for enrollment.  For more information, see

The Journal of Allergy and Clinical Immunology (JACI) is an official scientific journal of the AAAAI, and is the most-cited journal in the field of allergy and clinical immunology.

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