Rituximab for treatment of refractory multiple sclerosis relapses during pregnancy.

Case Summary: While multiple sclerosis (MS) disease activity declines during pregnancy, there are situations where MS relapses in pregnant women do occur. Mild relapses may be managed with close observation, but severe refractory relapses may require more aggressive management. We describe two cases of rituximab used for severe, refractory multiple sclerosis relapses during pregnancy. Rituximab did not appear to complicate either pregnancy and there were no further relapses for either women. Rituximab should not be overlooked in rare refractory cases, such as the rebound relapses sometimes seen following the discontinuation of lymphocyte-sequestering disease-modifying therapies.