Can real world data inform omalizumab treatment decisions during pregnancy?

Published online: May 27, 2019

When women with asthma become pregnant, they, along with their healthcare provider, must make informed decisions about which treatments to continue during pregnancy. Loss of asthma control increases the risk of some adverse pregnancy outcomes such as perinatal mortality, prematurity, and low birth weight. Therefore, pregnant women with asthma are typically advised to maintain asthma treatment throughout the pregnancy.

Most clinical trials exclude pregnant women and therefore, provide little or no information on any potential risks to the woman or her infant from a particular medication. Given this information gap, the medical community relies on observational studies from real world clinical practice – often referred to as real-world data – to assess any potential risks associated with treatments taken during pregnancy.   

In an article recently published in The Journal of Allergy & Clinical Immunology (JACI), Namazy and colleagues report the pregnancy and infant outcomes for 250 women with asthma who received omalizumab during pregnancy and in some cases, during breastfeeding, and who enrolled in a registry known as EXPECT. The registry collected information from the women and their healthcare providers during pregnancy and up to 18 months after delivery. The results were then compared to that of a comparator group of pregnant women with moderate to severe asthma who were not treated with omalizumab, identified from healthcare databases in the Canadian province of Quebec.

The study found the rate of major congenital anomalies (birth defects) or miscarriages was similar between EXPECT infants and the comparator infants. However, there was an increased rate of premature birth and low birth weight among the EXPECT infants, although the women in EXPECT also had more severe asthma and were more likely to be obese, which are known risk factors for these outcomes.

The findings suggest that omalizumab exposure in pregnancy is not associated with an increase in the risk of major congenital anomalies. This study also demonstrates the value of real-world data for providing important and practical evidence-based information for clinicians and pregnant women when that information cannot be collected in a traditional clinical trial. Finally, these results may be useful to pregnant women and their health care providers when they must make decisions regarding the use of omalizumab during pregnancy.   

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

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