This sheet is about exposure to benralizumab in pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your healthcare provider.
What is benralizumab?
Benralizumab is a monoclonal antibody that belongs to the group of medications known as ‘biologics’, used to treat patients with severe eosinophilic asthma. It is administered by an injection under the skin (subcutaneous) every 4 weeks for the first 3 doses, followed by once every 8 weeks thereafter. It is sold under the brand name Fasenra®.
I take benralizumab. Can it make it harder for me to get pregnant?
Studies have not been done to see if benralizumab could make it harder to get pregnant.
I just found out that I am pregnant. Should I stop taking benralizumab?
Talk with your healthcare providers before making any changes to how you take your medication. The benefits of taking your medication may outweigh the risks of untreated illness. Untreated asthma increases the chance for complications for both the person who is pregnant and the baby. For more information about asthma, please see the MotherToBaby fact sheet at https://mothertobaby.org/fact-sheets/asthma-and-pregnancy/.
Does taking benralizumab increase the chance for miscarriage?
Miscarriage can occur in any pregnancy. Studies have not been done to see if benralizumab increases the chance for miscarriage.
Does taking benralizumab increase the chance of birth defects?
Every pregnancy starts out with a 3-5% chance of having a birth defect. This is called the background risk. There are no human studies looking at exposure to benralizumab during pregnancy. It was recently reported that a person with hypereosinophilic syndrome who became pregnant while receiving benralizumab through a clinical trial delivered a healthy baby.
Animal studies done by the manufacturer did not show an increase in birth defects with exposure to benralizumab.
Could taking benralizumab cause other pregnancy complications?
It is not known if benralizumab can cause pregnancy complications.
Can taking benralizumab during pregnancy have any effects on my baby after birth?
There is not enough information to know if taking benralizumab during pregnancy will have an effect on a baby after birth. Monoclonal antibodies, such as benralizumab, cross the placenta during the third trimester of pregnancy and, in theory, could affect the baby’s immune system (the body’s ability to fight off infections).
Animal studies done by the manufacturer did not show weakened immune systems in offspring that were exposed to benralizumab during pregnancy.
Does taking benralizumab in pregnancy cause long-term problems in behavior or learning for the baby?
It is not known if benralizumab can cause long-term problems in behavior or learning.
Can my baby receive live vaccines before one year of age if I take benralizumab while pregnant?
Most vaccines given in the first 6 months of life are noninfectious and can be given to a baby even if benralizumab is present in their blood. Noninfectious vaccines are not live vaccines, meaning a person cannot get the infection from the vaccine.
Live vaccines usually contain a milder form of the virus or bacteria than what you might be exposed to in the community. Live vaccines always carry a small chance a person could get the infection from the vaccine. Live vaccines given in the newborn period are usually avoided in the first year of life, if possible, in case the child’s immune system does not respond to the vaccine as expected.
Live vaccines include measles-mumps-rubella (MMR), varicella (chicken pox) and rotavirus vaccines. Rotavirus is one of the leading causes of vomiting and severe diarrhea in children. The rotavirus vaccine is the only live vaccine that is routinely recommended for infants less than one year of age in the United States. It is the best way to protect infants against rotavirus.
Always be sure to let your pediatrician know of any medications or exposures during pregnancy and/or breastfeeding. They can discuss the risks and benefits of live vaccines with you.
Can I breastfeed my baby if I am taking benralizumab?
Benralizumab has not been well studied during breastfeeding. Because benralizumab is a very large protein, it is likely that very little medication would pass into breast milk. Benralizumab is not well absorbed by the gut, so any of the medication that gets into breast milk would be unlikely to enter the baby’s system. Babies who are born preterm (born before 37 weeks of pregnancy) have digestive systems that are not fully developed and may be able to absorb more of the medication through breast milk. Be sure to talk to your healthcare provider about all your breastfeeding questions.
I take benralizumab. Can it make it harder for me to get my partner pregnant or increase the chance of birth defects?
There are no studies looking at fertility or possible risks to a pregnancy when a male takes benralizumab. In general, exposures that fathers or sperm donors have are unlikely to increase the risks to a pregnancy. For more information, please see the MotherToBaby fact sheet Paternal Exposures at https://mothertobaby.org/fact-sheets/paternal-exposures-pregnancy/.
MotherToBaby is currently conducting a study looking at asthma and the medications used to treat asthma in pregnancy. If you would like to learn more about this study, please call 1-877- 311-8972 or visit https://mothertobaby.org/join-study/.
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OTIS/MotherToBaby encourages inclusive and person-centered language. While our name still contains a reference to mothers, we are updating our resources with more inclusive terms. Use of the term mother or maternal refers to a person who is pregnant. Use of the term father or paternal refers to a person who contributes sperm.
