Inrebic (fedratinib) is used to reduce symptoms of myelofibrosis (MF) in adults, including night sweats, itching, pain, and feeling full when eating, and also helps reduce spleen volume. It works by blocking overactive kinases, such as JAK2 and FLT3, which are involved in signaling pathways that cause inflammation in the bone marrow and spleen enlargement. Inrebic belongs to the class of kinase inhibitors and helps manage MF symptoms and complications.