Rituximab before and during pregnancy: A systematic review, and a case series in MS and NMOSD

To evaluate the safety of rituximab treatment before and during pregnancy in women with MS and neuromyelitis optica spectrum disorders (NMOSDs) who may be at risk of relapses by performing a systematic literature review combined with a retrospective single-center case series.

Studies were systematically identified in the PubMed, Google Scholar, and EMBASE using the key terms "pregnancy" and "rituximab"; 22 articles were included for review (>17,000 screened). Then, patients with MS and NMOSD from 1 center (University of California, San Francisco) exposed to rituximab before conception were identified through medical record review.

Systematic review: We identified 102 pregnancies with rituximab use within 6 months of conception: 78 resulted in live births and 12 in spontaneous abortions. Of 54 live births with reported gestational age, 31 occurred at term (37 weeks+) and 2 before 32 weeks. When checked, B-cell counts were low in 39% of newborns and normalized within 6 months. Case series: we identified 11 pregnancies (1 ongoing) in 10 women (7 MS and 3 NMOSD) treated with rituximab within 6 months of conception. All completed pregnancies resulted in term live births of healthy newborns (1 lost to follow-up at term). No maternal relapses occurred before/during pregnancy; 1 occurred postpartum (NMOSD).

No major safety signal was observed with rituximab use within 6 months of conception. Beyond the need for monitoring neonatal B cells, these observations support prospectively monitoring a larger patient cohort to determine whether rituximab may safely protect women with MS and NMOSD who are planning a pregnancy against relapses.