Anti-CD20 Therapy in Postpartum Period in Multiple Sclerosis

Infused anti-CD20 therapies are monoclonal antibodies that are minimally secreted in breast milk and unlikely to be digested orally. In this partially industry-funded study, investigators prospectively measured the concentration in breast milk for 12 months after 59 pregnancies of 57 cis women (55 with multiple sclerosis and 2 with neuromyelitis optica spectrum disease), of whom 33 received postpartum ocrelizumab and 26 received postpartum rituximab. Participants were taking anti-CD20 medication before conception for 56% of pregnancies.

Median time from delivery to postpartum infusion was 3 months. Anti-CD20 concentration in breast milk peaked 1 to 7 days postinfusion and was nearly undetectable after 90 days. Median maximum concentration wa…