IFNA1 and acquired polycythemia vera: Preliminary results of a Phase II study using a combination therapy between pegylated IFN-α and ruxolitinib on 50 MPN patients (32 PV and 18 PMF patients), most of whom were resistant and/or intolerant to IFN-α as a monotherapy, saw complete haematologic responses in 44% and 58% of PV and PMF patients respectively (114).