An observational study in Multiple Sclerosis, sponsored by Biogen. Recruiting at 8 sites in 7 countries. Open to female participants. Per ClinicalTrials.gov, last updated 2026-08-11.
Sponsored by Biogen · Observational
The primary objectives of the study are to estimate the risk of major congenital malformations (MCMs) in infants born to women with multiple sclerosis (MS) who were exposed to diroximel fumarate (DRF) at any time from 2 weeks after the first day of their last menstrual period (LMP) up through the first trimester of pregnancy and to comparatively evaluate pregnancy outcomes with MCMs in women with MS who were exposed to DRF at any time from 2 weeks after the first day of their LMP through the first trimester of pregnancy with the following: i) women with MS who were unexposed to disease modifying therapies (DMTs) and, ii) women with MS who were exposed to other DMTs (e.g., Avonex and Tysabri Pregnancy Registries).
The secondary objective of the study is to evaluate pregnancy outcomes in women with DRF exposure at any time from 2 weeks after the first day of their LMP through the end of pregnancy compared with the following: i) women with MS who were unexposed to DMTs, ii) women with dimethyl fumarate (DMF) exposure, iii) women with MS who were exposed to other DMTs (e.g., Avonex and Tysabri Pregnancy Registries), and iv) women without MS (e.g., women from external, general population comparators).
3,460 studies on the registry are indexed under Multiple Sclerosis; 660 are open to participants now.
This study's planned enrollment of 908 is above the median of 100 across 1,016 observational studies indexed under Multiple Sclerosis.
Browse Multiple Sclerosis studies →Biogen is the lead sponsor of 494 studies on the registry; 22 are open to participants now.
Of its 98 completed or terminated interventional studies of FDA-regulated products, 49 (50%) have results posted.
Counted across the registry records on this site, refreshed daily.
The study population will include pregnant female participants with MS who were exposed to DRF at any time from 2 weeks after the first day of their LMP up through any time during pregnancy and compared with pregnancies among women with MS who were exposed to DMF, women with MS who were exposed to other DMTs (e.g., Avonex and Tysabri Pregnancy Registries), women with MS who were unexposed to DMTs, and women without MS.
Participants will be classified into 2 enrolment types, Prospective and Retrospective. Prospective registration:a report of a pregnancy enrolled prior to knowledge of the pregnancy outcome, including prior to the detection of a congenital malformation at prenatal testing. Women who enrol after any knowledge of the pregnancy outcome will be enrolled as retrospective cases but will not be included in the primary analysis, i.e.,pregnancies with a prenatal testing result indicative of any congenital malformation/pregnancies with known outcomes at time of initial report.
Key Inclusion Criteria:
Documentation that the participant was one of the following:
Key Exclusion Criteria:
- None
NOTE: Other protocol defined Inclusion criteria may apply
Pregnant women with MS who were exposed to DRF at any time from 2 weeks after the first day of their LMP through the end of pregnancy.
Drug: Diroximel Fumarate
Pregnant women with MS who were exposed to other DMTs (e.g., Avonex and Tysabri Pregnancy Registries) at any time from 2 weeks after the first day of their LMP through the end of pregnancy.
Drug: Avonex · Biological: Tysabri
Pregnant women who were unexposed to DMT which is defined as either never received a DMT or discontinued treatment with DRF at least 1 day before 2 weeks after the first day of their LMP or discontinued a non-Registry-specified MS DMT more than 5 times its half-life prior to 2 weeks after the first day of their LMP.
Pregnant women with MS who were exposed to DMF at any time from 2 weeks after the first day of their LMP through the end of pregnancy.
Drug: Dimethyl Fumarate
Pregnant women with external, general population comparators.
Administered as specified in the treatment arm.
Also known as: VUMERITY, BIIB098
Administered as specified in the treatment arm.
Also known as: BG9418, interferon beta-1a
Administered as specified in the treatment arm.
Also known as: Natalizumab, BG00002
Administered as specified in the treatment arm.
Also known as: Tecfidera, DMF, BG00012
Number of Major Congenital Malformations (MCMs)
MCMs include abnormalities in structural development that are medically or cosmetically significant are present at birth, and persist in postnatal life unless or until repaired as evaluated by independent advisors used throughout the registry.
Time frame: Up to 52 weeks postdelivery
Number of Elective or Therapeutic Terminations
Elective or therapeutic pregnancy termination is any induced or voluntary fetal loss during pregnancy. It will be subclassified as elective or therapeutic pregnancy terminations as whether it was due to a fatal anomaly or not.
Time frame: Up to 9 months of pregnancy
Number of Spontaneous Abortions
Spontaneous abortion is defined as any loss of a fetus due to natural causes before 22 weeks of gestation.
Time frame: Before 22 weeks of gestation
Number of Fetal Deaths Including Still Birth
Fetal death or stillbirth refers to the death of a fetus prior to complete expulsion or extraction from its mother at or after 22 weeks of gestation. Death is indicated by the fact that, after such separation, the fetus does not show any evidence of life (e.g., heartbeat, umbilical cord pulsation, or definite movement of voluntary muscles). Fetal death occurring at or after 22 weeks but before 28 weeks of gestation is considered an early fetal loss. Fetal death occurring at or after 28 weeks is considered a late fetal loss.
Time frame: At or after 22 weeks of gestation
Number of Live Births
A live birth refers to a complete expulsion or extraction from its mother of a surviving neonate breathing, or showing any other evidence of life, such as heartbeat, umbilical cord pulsation, or definite movement of voluntary muscles, whether the umbilical cord has been cut or the placenta is attached. Any live birth before 37 weeks of gestation will be considered premature birth. Any live birth at or after 37 weeks but before 42 weeks of gestation will be considered full-term birth. Any live birth at or after 42 weeks of gestation will be considered post-term birth.
Time frame: Up to delivery (approximately 10 months)
Number of Ectopic Pregnancies
Time frame: Up to 9 months of pregnancy
Number of Molar Pregnancies
Time frame: Up to 9 months of pregnancy
Number of Maternal Deaths
Maternal death is death of a pregnant woman during pregnancy, labor, or delivery. Registry will also report maternal deaths that occur up to 12 weeks postdelivery.
Time frame: Up to 12 weeks postdelivery
Number of Neonatal Deaths
Neonatal death is death occurring in a neonate prior to 28 days of life.
Time frame: Prior to 28 days postdelivery
Number of Perinatal Deaths
Perinatal death is death occurring at or after 28 days of life and prior to 12 weeks of life.
Time frame: At or after 28 days to 12 weeks postdelivery
Number of Infant Deaths
Infant death is death occurring between 12 and 52 weeks of life, inclusive.
Time frame: Between 12 to 52 weeks postdelivery
Number of Serious or Opportunistic Infections in Liveborn Children
Time frame: Up to 52 weeks postdelivery
Number of Infants with Abnormal Postnatal Growth and Development
Infant growth measurements will be used to estimate gender-specific weight-for-length, head circumference-for-age, length-for-age, and weight-for-age percentiles. Developmental milestones (i.e., social/emotional, language/communication, neurocognitive, movement/physical development) will be used to determine results of infant status (i.e., below, above, or at age-appropriate achievement).
Time frame: Up to 52 weeks postdelivery
Number of Participants with Pregnancy Complications
Pregnancy complications may include incidences of pre-eclampsia, eclampsia, pregnancy-induced hypertension, preterm labor, gestational diabetes and placenta previa.
Time frame: Up to 9 months of pregnancy
Plan to share: Yes — In accordance with Biogen's Clinical Trial Transparency and Data Sharing Policy on https://www.biogentrialtransparency.com/
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