Pregnancy outcomes of women with multiple sclerosis treated with ocrelizumab in Canada: A descriptive analysis of real-world data

To report and describe the real-world use of ocrelizumab in women with multiple sclerosis (MS) in Canada before and/or during pregnancy as well as their fetal outcomes.

We identified retrospective and prospective Canadian pregnancy exposure cases from the Roche Global Safety Database from November 5, 2008 until March 31, 2021, and linked these cases to information within the Canadian Roche Patient Support Program (COMPASS). The analysis only included spontaneous reports or those from a non-interventional program. Details of the pregnancy exposures, fetal outcomes, as well as relevant patient characteristics, were collected.

A total of 107 cases of maternal exposures were retrieved, with 104 (97.2%) being prescribed ocrelizumab for relapsing-remitting MS (RRMS) and 105 (98.1%) being reported from the COMPASS program. Of these cases, 85 (79.4%) were prospective and 22 (20.6%) retrospective. Cases were pooled (n = 65), and unknown/lost to follow-up outcomes and ongoing pregnancies were excluded. All cases reporting an outcome were analyzed, including 47 (72.3%) live births (44.7% full term, 8.5% preterm, 46.8% unknown gestational age), 13 (20.0%) spontaneous abortions, 2 (3.1%) therapeutic abortions/elective terminations, and 3 (4.6%) ectopic pregnancies. One major congenital anomaly of the limb (polydactyly) was reported; however, multiple confounders were likely contributors. Of the total maternal exposures (n = 107), 50 cases (46.6%) were not exposed to ocrelizumab in utero, with 32 of these (64.0%) receiving their last ocrelizumab infusion >3 but ≤6 months prior to conception, 17 (34.0%) receiving it >6 months prior to conception and 1 case receiving it at an unknown time point not in utero. Among the 37 (34.6%) maternal exposure cases exposed in utero, 22 (59.5%) received their last ocrelizumab infusion ≤3 months prior to conception.

The data presented, although not without limitations, continues to suggest no increased risk of congenital anomalies and are consistent with ocrelizumab global pregnancy safety data and epidemiological rates.