Immunotherapy based approaches in myelofibrosis

Introduction: Aberrant regulation of the immune system with up-regulation of pro-inflammatory cytokines contributes to disease pathophysiology in myelofibrosis (MF). Therapeutic options for MF associated anemia, thrombocytopenia, and bone marrow fibrosis remain limited. Areas covered: This review focuses on immune based therapies in MF, including immunomodulatory imide drugs (IMiDs), interferons, monoclonal antibodies and targeted agents (SL-401), and checkpoint inhibitors. Published literature was reviewed using available databases (PubMed, Cochrane, Scopus) and web pages (clinicaltrials.gov). IMiDs, such as thalidomide, lenalidomide and pomalidomide, have demonstrated efficacy in treating MF associated cytopenias. Interferon-alpha may be beneficial in early phase MF due to its effects on neoplastic bone marrow. Monoclonal antibodies are designed to target overexpressed antigens on tumor cells and induce targeted cell death by either delivering a toxic payload, or to unleash anti-tumor T-cells by blocking T-cell inhibitory checkpoints. Expert commentary: Immune based therapy is being evaluated in a number of hematologic malignancies with encouraging data in Hodgkins, multiple myeloma, myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Ongoing and planned clinical trials of these agents, either alone or in various combinations with other targeted therapies, such as JAK-STAT or histone deacetylase inhibitors, and anti-fibrotic agents, will reveal the full potential of immune therapies in MF.