IFNA2 and acquired polycythemia vera: The underlying phase II study did prove in a cohort with 50 MPN patients, of which 47 were resistant or intolerant to IFN-α2 monotherapy, that a combination therapy with pegylated IFN-α2 and Ruxolitinib could indeed reduce the JAKV617F allelic burden and cause complete or partial remission (9% in PV, 39% in MF) or sustained complete hematologic response (44% in PV, 58% in MF).