LemtradaŽ (Alemtuzumab) Pregnancy Exposure Registry: Study Design and Enrollment for Pregnant Women with Multiple Sclerosis Exposed to Alemtuzumab

Background: Alemtuzumab is a humanized anti-CD52 monoclonal antibody administered as 2 IV courses and approved for the treatment of relapsing-remitting multiple sclerosis. MS is frequently diagnosed in women of childbearing age, but there are no clinical studies of alemtuzumab in pregnant women. Although alemtuzumab concentration is low or undetectable in serum within approximately 30 days after administration, it is recommended that women of childbearing potential use contraception for 4 months after treatment. During the alemtuzumab clinical trials, a number of pregnancies were reported; outcomes did not suggest an adverse pattern. Animal studies did not suggest teratogenicity when alemtuzumab was administered during gestation.

Objectives: To report the study design and enrollment procedures for the International LEMTRADA® (Alemtuzumab) Pregnancy Exposure Registry.

Methods: This international, prospective, noninterventional, observational safety study will evaluate pregnancy outcomes in women who were pregnant during or became pregnant within 4 months after an alemtuzumab infusion, and compare them with outcomes from external cohorts of women without MS and women with MS who have not been exposed to alemtuzumab during pregnancy. Data will be collected during each trimester and within 6 weeks after the end of pregnancy, plus a 1-year follow-up of infant health status for all live births. Outcomes include spontaneous abortion, stillbirth, fetal major malformations, preterm birth, and small size for gestational age at birth and up to 1 year of age. A sample size of approximately 185 women exposed to alemtuzumab during pregnancy is expected to achieve approximately 150 women followed up to 1 year post-delivery. US pregnancy cases can be reported to: INC Research Lemtrada Pregnancy Registry Team; phone: +1- 866-758-2990; email: LEMTRADAPregnancyRegistry@incresearch.com.

Results: Enrollment began in early 2015 and will continue for approximately 4 years. 

Conclusions: This registry will provide valuable data on pregnancy outcomes and development in the first year of life in infants born to women exposed to alemtuzumab during pregnancy. Referrals are welcomed.