IFNA1 and acquired polycythemia vera: In a recent phase-2 clinical trial from the Myeloproliferative Disorders Research Consortium [133], 50 patients with PV and 65 with ET, who were refractory or intolerant to HU, received subcutaneous pegylated IFN-α (starting dose 45 mcg weekly and titrated to a maximum of 180 mcg) with 69% overall response rate, including 60% (22% complete response) in patients with PV.