Efficacy and Safety of Ropeginterferon Alfa-2b in Pregnant Women With Myeloproliferative Neoplasms: Case Series of Three Subtypes and Review.

Managing myeloproliferative neoplasms (MPNs) during pregnancy is challenging due to increased thrombotic risk and limited cytoreductive options. Ropeginterferon alfa-2b (ropeginterferon), a long-acting mono-pegylated interferon, has limited data in this setting. We report a Korean multicenter case series of four pregnancies across MPN subtypes, including prefibrotic/early primary myelofibrosis, essential thrombocythemia, and polycythemia vera. Ropeginterferon was used during pregnancy or prior to conception (250-500 μg every 2-12 weeks) with aspirin and/or low-molecular-weight heparin. Hematologic responses were sustained throughout pregnancy without treatment-limiting adverse events. All pregnancies resulted in live births without major maternal or neonatal complications. Within the limits of a small retrospective series, ropeginterferon appeared to be a feasible cytoreductive option in these MPN pregnancies, including pre-conception and intra-pregnancy use; these preliminary observations warrant confirmation in larger prospective studies.