Report on Pacritinib (VONJO™): A Comprehensive Monograph

Executive Summary and Drug Profile

Overview

Pacritinib is an orally bioavailable, small molecule multi-kinase inhibitor developed for the treatment of myelofibrosis (MF), a life-threatening bone marrow disorder.[1] Pharmacologically, it is classified as an inhibitor of Janus kinase 2 (JAK2) and FMS-like tyrosine kinase 3 (FLT3), targeting key signaling pathways implicated in the pathogenesis of myeloproliferative neoplasms.[4] Marketed in the United States under the brand name VONJO™, pacritinib represents a significant therapeutic advancement, particularly for a subset of patients with limited treatment options.[6] It is identified by DrugBank ID DB11697 and CAS Number 937272-79-2.[8]

Core Indication and Clinical Niche

Pacritinib occupies a unique and critical position in the clinical armamentarium as the first and only therapy approved by the U.S. Food and Drug Administration (FDA) for the treatment of adults with intermediate- or high-risk primary or secondary (post-polycythemia vera or post-essential thrombocythemia) myelofibrosis who present with severe thrombocytopenia, specifically a platelet count below 50×109/L.[9] This specific indication addresses a profound unmet medical need, as other approved JAK inhibitors, such as ruxolitinib and fedratinib, are often associated with myelosuppressive effects that can exacerbate or induce thrombocytopenia, thereby limiting their use or requiring dose interruptions in this vulnerable patient population.[12]

Efficacy and Safety Synopsis