Polycythemia vera has long been managed with phlebotomy and hydroxyurea, neither of which addresses the underlying clonal disease. Besremi (ropeginterferon alfa-2b) brought interferon into formal approval for the condition.
It is a long-acting interferon injected every two weeks, with the interval extendable once hematocrit is controlled, and the first interferon approved specifically for polycythemia vera. Patients can begin it regardless of prior treatment history.
Besremi holds orphan designation with no biosimilar competition, competing against low-cost hydroxyurea and ruxolitinib. Evidence that interferons may modify disease course rather than only control counts is the key factor shaping its long-term positioning.
