Improvement of bone marrow fibrosis with ruxolitinib: will this finding change our perception of the drug?

Ruxolitinib, a JAK1 and JAK2 inhibitor, has been tested and approved for the treatment of primary and secondary myelofibrosis. Reduction of spleen volume and improvement of constitutional symptoms and quality of life have been reported as the major findings in sponsored randomized clinical trials. Recent data indicated that the drug improves bone marrow fibrosis and that different targets may be involved in this response. These new data, which require confirmation in prospective trials, may change our perspectives and therapeutic strategies for this disease.