The decision to terminate the Fasenra pregnancy study and cancel the commitment to conduct additional pregnancy-related pharmacovigilance activities was made by the EMA following MAH's failed attempts to address patient recruitment challenges.

This is a prospective, observational, exposure cohort study of pregnancy and infant outcomes in women with asthma exposed to benralizumab anytime during pregnancy, or within 8 weeks prior to the first day of the last menstrual period (LMP)

The objective of the study is to monitor planned or unplanned pregnancies to evaluate potential teratogenic effect (birth defect) when exposed to benralizumab compared to two unexposed comparator groups.

The primary outcome is major structural birth defects (abnormalities in development of structures of the body) and the secondary outcomes are preterm delivery (premature baby), small for gestational age infants (small for weight, length, and/or head circumference), spontaneous abortion (miscarriage), stillbirth (baby born without signs of life), elective termination (voluntary abortion) and small for age postnatal growth to one year of age (small for weight, length and/or head circumference). The birth prevalence or incidence of outcomes in women exposed to benralizumab, and their infants, will be compared to those observed in two unexposed comparator groups: a disease-matched comparison group of women who have not used benralizumab during pregnancy or within 8 weeks of their last menstrual period (LMP), but who have used other anti-asthmatic medications (treated disease comparison group), and a comparison group of healthy women who do not have a diagnosis of asthma, have not had exposure to a known human teratogen (substance that causes birth defect), and have not taken benralizumab in pregnancy (healthy comparison group).

Participants will be recruited into the three cohorts concurrently, on the basis of the following inclusion/exclusion criteria:

Cohort 1: Benralizumab-Exposed

Inclusion Criteria:

• Currently pregnant women diagnosed with asthma who contact the OTIS Research Center and who have been exposed to benralizumab for any number of days, at any dose, and at any time from 8 weeks before the first day of LMP up to and including the end of pregnancy.
• Eligible participants will be currently pregnant women who agree to the conditions and requirements of the study including the interview schedule and release of medical records.

Exclusion Criteria:

• Women who have had exposure to another biologic, used for any indication, anytime during pregnancy or within 8 weeks of LMP.
• Women will not be eligible for Cohort 1 if they first contact the OTIS Research Center after prenatal diagnosis of a major structural birth defect.
• Restrospective cases (outcome of pregnancy known prior to enrollment).
• Women who have enrolled in the current study with a previous pregnancy.

Cohort 2: Treated Diseased Comparison

Inclusion Criteria:

• Currently pregnant women diagnosed with asthma and exposed to asthma medications for any number of days, at any dose, and at any time from LMP up to the date of enrollment, who contact the OTIS Research Center but who were not exposed to benralizumab during pregnancy or within 8 weeks prior to LMP.
• Eligible participants will be currently pregnant women who agree to the conditions and requirements of the study including the interview schedule and release of medical records.

Exclusion Criteria:

• Women with exposure to benralizumab any time during pregnancy or within 8 weeks prior to LMP.
• Women will not be eligible for Cohort 2 if they first come in contact with the OTIS Research Center after prenatal diagnosis of a major structural birth defect.
• Retrospective cases (outcome of pregnancy known prior to enrollment).
• Women who have enrolled in the current study with a previous pregnancy.

Cohort 3: Non-Asthmatic Comparison

Inclusion Criteria:

• Currently pregnant women who contact the OTIS Research Center.
• Eligible women may potentially have been exposed to non-teratogenic agents during this pregnancy.
• Women who agree to the conditions and requirements of the study including the interview schedule and release of medical records.

Exclusion Criteria:

• Women who have been exposed to any known teratogenic agents as determined by the OTIS Research Center (list in Annex 1) for any number of days, at any dose, from the first day of the last menstrual period up to and including the end of pregnancy.
• Women with a self-reported diagnosis of asthma, current or previous.
• Women will not be eligible for Cohort 3 if they come in contact with the OTIS Research Center after prenatal diagnosis of a major structural birth defect.
• Retrospective cases (outcome of pregnancy known prior to enrollment).
• Women who have enrolled in the current study with a previous pregnancy.

Pregnant women who have or have not used benralizumab anytime in pregnancy for asthma.

The study population includes pregnant women who reside in the US or Canada who have or have not used benralizumab anytime in pregnancy for asthma.