Definition

A drug used to treat adults with certain types of primary myelofibrosis (MF), post-polycythemia vera MF, post-essential thrombocythemia MF, or polycythemia vera, and adults and children aged 12 years and older with acute or chronic graft-versus-host disease. It is also being studied in the treatment of some types of cancer. Ruxolitinib phosphate blocks a protein called JAK, which may help keep abnormal blood cells or cancer cells from growing. It may also lower the body’s immune response. Ruxolitinib phosphate is a type of tyrosine kinase inhibitor. Also called Jakafi.