314. MATERNOFETAL OUTCOMES IN PREGNANCIES WITH GESTATIONAL RITUXIMAB EXPOSURE

Abstract

Background: The optimal peripregnancy management of women receiving immunosuppression with rituximab remains uncertain. In each case, the risk of disease relapse with cessation of therapy must be weighed against the potential fetal risk of B cell depletion during pregnancy. Method(s): We performed a retrospective analysis of women with autoimmune disease who were treated with rituximab and had documented B cell depletion during pregnancy. Outcomes of interest were disease relapse, infectious complications during pregnancy, and maternofetal outcomes. SkRipe tsou Mltasi:n W e nidteennttified 17 pregnancies in which maternal rituximab exposure occurred, including 1 case of twins. The last rituximab dose was administered at a median of 2.72 months (IQR 0.75-4.38) prior to the estimated date of conception, and no doses were given at > 1 month following conception. Among 16 patients with available data, B cells recovered during pregnancy in 5 patients, while 11 patients delivered prior to confirmed B cell return. B cells were detected in fetal cord blood despite the absence of maternal B cells in 3 cases. Maternofetal outcomes are presented in Table 1. One case of fetal demise occurred due to Beckwith-Wiedemann syndrome. The remaining 16 pregnancies resulted in viable babies. Seven births were preterm (before 37 weeks) with low birth weight (<2500 g). Four babies were delivered via C-section. Patient 3 experienced pyelonephritis in one pregnancy and a disease flare with each pregnancy (progressive airway disease secondary to GPA). Patient 5 experienced gestational diabetes mellitus (DM) in one pregnancy. Patient 8 developed preeclampsia and was induced at 36 weeks. In 10 patients, low-dose prednisone and/or azathioprine was administered to prevent relapse or for the treatment of established adrenal insufficiency. Conclusion(s): Maternofetal outcomes appear favorable when rituximab is administered prior to conception. Additional data is needed to define the optimal management of rituximab in the peripregnancy period.