Natalizumab treatment and pregnancy in multiple sclerosis: A reappraisal of maternal and infant outcomes after 6 years.

OBJECTIVES

To assess the impact of timing of natalizumab cessation/redosing on long-term maternal and infant outcomes in 72 out of the original 74 pregnancies of the Italian Pregnancy Dataset in multiple sclerosis (MS).

METHODS

Maternal outcomes in patients who received natalizumab until conception and restarted the drug within 1 month after delivery ("treatment approach," (TA)) and patients who stopped natalizumab before conception and/or restarted the drug later than 1 month after delivery ("conservative approach," (CA)) were compared through multivariable Cox regression analyses. Pediatric outcomes were assessed through a semi-structured questionnaire.

RESULTS

After a mean follow-up of 6.1 years, CA (hazard ratio (HR) = 4.1, 95% CI 1.6-10.6,  = 0.003) was the only predictor of relapse occurrence. Worsening on the Expanded Disability Status Scale (EDSS) was associated with higher annualized relapse-rate during the follow-up (HR = 3.3, 95% CI 1.4-7.9  = 0.007). We found no major development abnormalities in children.

DISCUSSION

Our data confirm that TA reduces the risk of disease activity; we did not observe an increase in major development abnormalities in the child.