An updated review of the JAK1/2 inhibitor (ruxolitinib) in the Philadelphia-negative myeloproliferative neoplasms.

Ruxolitinib (Rux), a JAK1/2 inhibitor, has been approved for patients with myelofibrosis and in polycythemia vera with inadequate response/intolerance to hydroxycarbamide. Studies have demonstrated that Rux improves disease-related symptoms and splenomegaly. A late emerging observation from two Phase III trials was that Rux was associated with survival advantage in comparison with placebo or other available therapies in myelofibrosis. Important data suggest that for polycythemia vera Rux improved control of blood counts. Main hematological side effects are anemia and thrombocytopenia predominantly at the beginning of the treatment. Some studies and case reports highlighted potential risks of nonmelanoma skin cancers and increased risk of infection including reactivation of hepatitis B, tuberculosis or herpes zoster infections after Rux treatment.