A recent study indicates that treatment with Zeposia (ozanimod) during early pregnancy could be safe for women diagnosed with multiple sclerosis (MS) or inflammatory bowel diseases. The findings suggest that receiving Zeposia during the first trimester of pregnancy did not result in an increased incidence of fetal malformations or adverse pregnancy outcomes, such as premature birth and spontaneous abortion, compared to the general population. Similar outcomes were observed for pregnant partners of individuals with MS.
However, the study did not include participants exposed to Zeposia after the first trimester, leaving the safety of Zeposia later in pregnancy uncertain. This information was detailed in the study titled “Pregnancy Outcomes in the Ozanimod Clinical Development Program in Patients With Ulcerative Colitis, Crohn’s Disease, and Relapsing Multiple Sclerosis,” published in Inflammatory Bowel Diseases.
In MS, the immune system mistakenly attacks and damages the myelin sheath, a protective layer around nerve fibers crucial for proper nervous system function.
Zeposia is approved for adults with relapsing forms of MS and ulcerative colitis, and it is under evaluation for Crohn’s disease. The medication functions by binding to the sphingosine 1-phosphate (S1P) receptor on the surface of immune cells, keeping them within lymph nodes where immune cells mature and are stored. Zeposia can also penetrate the brain and potentially support the survival of nerve cells and oligodendrocytes, which produce myelin. Both ulcerative colitis and Crohn’s disease are inflammatory bowel diseases characterized by chronic inflammation in the gastrointestinal tract.
The researchers noted, “Currently, there are no adequate and well-controlled clinical studies on developmental risks associated with the use of ozanimod [Zeposia] in pregnant women.”
Studying Pregnancy Outcomes in MS Patients Treated with Zeposia
The study reported pregnancy outcomes in 78 pregnancies among 6,057 patients and healthy volunteers who received Zeposia, including 2,973 individuals with relapsing MS and 2,225 with inflammatory bowel diseases. All participants were enrolled in clinical trials of Zeposia, funded by Bristol Myers Squibb, the therapy’s marketer.
All exposures to Zeposia occurred during the first trimester, with patients discontinuing the medication after confirming their pregnancy, except for those who opted for termination. Zeposia’s prescribing information advises against pregnancy while taking the medication.
Among pregnant women with MS, 57 gave birth to 33 children. One child experienced growth retardation during late pregnancy but exhibited subsequent normal development. Another birth showed a congenital abnormality (a duplex kidney), while eight pregnancies ended due to spontaneous abortions and 10 due to elective terminations. Similar outcomes were observed among women with ulcerative colitis or Crohn’s disease who received Zeposia.
The researchers stated, “In patients… who had ozanimod exposure during early pregnancy, incidences of spontaneous abortion, preterm birth, and congenital abnormalities were comparable to the expected ranges within the general population.”
Moreover, 29 partners of patients with relapsing MS or inflammatory bowel diseases, or healthy volunteers who received Zeposia, became pregnant. Among the 21 live births, five were premature, and three had a congenital abnormality, which was not suspected to be treatment-related. One spontaneous abortion was reported, with no elective terminations.
However, the researchers acknowledged the small sample size and the possibility of underreported partner pregnancies, emphasizing the need for future studies to address pregnancy outcomes in larger cohorts of pregnant women or partners of individuals treated with Zeposia.
They concluded, “Studies analyzing pregnancy outcomes of patients exposed to ozanimod later in pregnancy are also needed to provide a more complete profile of ozanimod safety during pregnancy.” A registry is currently monitoring pregnancy outcomes in MS patients treated with Zeposia or other MS medications during pregnancy.
