RecruitingPhase 2Drug trialPegylated Interferon α-2b in Combination With Ruxolitinib for Treating Hydroxyurea-resistant/Intolerant PVStudy purpose: To compare the efficacy and safety of pegylated interferon α-2b in combination with ruxolitinib versus pegylated interferon α-2b alone for treating hydroxyurea-resistant or hydroxyurea-intolerant polycythemia vera.