Therapeutic efficacy of recombinant interferon-alpha in polycythaemia vera.

The therapeutic efficacy of recombinant interferon-alpha (rIFN-alpha) has been evaluated in 7 patients with polycythaemia vera (PV), diagnosed according to the criteria of the Polycythemia Vera Study Group. Six complete responses and one partial response were achieved. Pruritus significantly improved in 80% (4/5) of the cases. Recombinant interferon-alpha had to be discontinued in 1 patient because of grade 3-4 nephrotoxicity according to WHO criteria. rIFN-alpha therapy significantly decreased the phlebotomy requirements and improved the mean corpuscular volume, erythrocyte and platelet counts, pruritus complaints and the degree of splenomegaly (p < 0.05). rIFN-alpha seems to be an effective treatment modality for the myeloproliferation of PV and pruritus complaints.