JAK2 and myelofibrosis: Fedratinib (INREBIC®, also known as SAR302503 or TG101348) is an oral, small molecule, selective Janus kinase 2 (JAK2) inhibitor, with activity against both wild-type and mutant JAK2, approved in the United States for the treatment of adult patients with myelofibrosis (MF) [1].