Peginterferon alfa-2a for treating essential thrombocythaemia or polycythaemia vera

Peginterferon alfa-2a is approved for the treatment of essential thrombocythaemia (ET) and polycythaemia vera (PV) in adults. ET and PV are rare blood cancers where the bone marrow makes too many blood cells. ET mainly increases platelets (cells in the blood which help with clotting), which can cause blood clots, headaches, or burning pain in the hands and feet. PV mainly increases red blood cells, making the blood thicker, reducing blood flow to organs and raising the risk of clots, strokes, and heart attacks, and it can also cause itching or gout. Both conditions usually develop slowly but can sometimes lead to scarring of the bone marrow or leukaemia (a type of blood cancer). Both ET and PV are linked to changes in certain genes and are more common in older adults, though they can affect people at any age.