Exposure to multiple sclerosis (MS) monoclonal antibody treatment during breastfeeding appeared to have no negative effect on the early development or health of infants, registry data in Germany showed.
Over the first 3 years of follow-up, no links emerged between exposure to monoclonal antibody drugs and annual hospitalization (rate ratio [RR] 1.23, P=0.473), annual systemic antibiotic use (RR 1.55, P=0.093), developmental delay (OR 1.16, P=0.716), or weight at follow-up, reported Kerstin Hellwig, MD, of Ruhr University in Bochum, Germany, and co-authors in an abstract released in advance of the American Academy of Neurology annual meeting.
"Our data show infants exposed to these medications through breastfeeding experienced no negative effects on health or development within the first 3 years of life," Hellwig said in a statement.
"Most monoclonal antibody medications for multiple sclerosis are not currently approved for use while a mother is breastfeeding. Yet MS can develop during the childbearing years of life," Hellwig noted.
"Since the risk of MS relapses increases after giving birth, some mothers may need or want to restart these therapies, so it is important to determine whether these medications -- through breast milk -- have a negative impact on a child's development," she added.
The study used data from the of women with MS and neuromyelitis optica spectrum disorders (NMOSD). The researchers assessed four drugs used during breastfeeding: natalizumab (Tysabri), ocrelizumab (Ocrevus), rituximab (Rituxan), and ofatumumab (Kesimpta).
Hellwig and colleagues studied 183 infants born to mothers taking monoclonal antibodies while breastfeeding; of these, 180 had mothers with MS and three had mothers with NMOSD. The researchers compared them with a control group of 183 infants whose mothers did not use monoclonal antibodies while breastfeeding, matched for exposure to MS medications shortly before or during pregnancy. There were no significant demographic differences between groups.
Monoclonal antibody exposure during breastfeeding started at a median of 19 days postpartum. The median duration of breastfeeding was 172 days.
Natalizumab was most commonly used (68.31%), followed by ocrelizumab (18.58%), rituximab (6.01%), and ofatumumab (5.46%). In two cases, treatment switched from natalizumab to ocrelizumab during breastfeeding; in one case, it switched from rituximab to ocrelizumab. Three children had previously been breastfed on glatiramer acetate (Copaxone or others) and two on interferons.
Only about one-third of the infants in the study were followed for the full 3 years, Hellwig said. Nonetheless, the research is valuable because it compares "outcomes in potentially exposed babies with those in a control group," observed Riley Bove, MD, MSc, of the University of California San Francisco, who wasn't involved in the study.
It's important to continue monitoring these children "to ensure that there are no longer-term risks of infection, growth difficulties, and potentially autoimmunity," Bove told 鶹ý.
Other studies that assess breastfeeding exposure to MS monoclonal antibodies are underway, she noted, including the open-label of B cell levels in infants of lactating women on ocrelizumab.
"The SOPRANINO study has finished enrollment and we expect a study readout within the next year," Bove said.
Disclosures
The German Multiple Sclerosis and Pregnancy Registry is partly supported by the Innovation Fund of the Federal Joint Committee, Almirall Hermal GmbH, Biogen GmbH Germany, Hexal AG, Merck Serono GmbH, Novartis Pharma GmbH, Roche Deutschland GmbH, Sanofi Genzyme, and Teva GmbH.
Hellwig reported relationships with Teva, Biogen, Novartis, Roche, Merck, Genzyme, Bayer, BMS, Janssen, and INC Research.
Bove reported relationships with Horizon, EMD Serono, TG Therapeutics, Janssen, Biogen, Roche, Genentech, Novartis, and Eli Lilly.
Primary Source
American Academy of Neurology
Witt L, et al "Child development after exposure to monoclonal antibodies during breastfeeding" AAN 2024.