Pacritinib is a type of medication known as a kinase inhibitor. It works by blocking specific enzymes in the body called kinases, particularly Janus associated kinase 2 (JAK2), mutant JAK2V617F, FLT3, and IRAK1. These kinases are involved in the signaling pathways that regulate blood cell production and immune function. In certain blood cancers, like myelofibrosis, these pathways become overactive, leading to abnormal growth of blood cells and symptoms such as an enlarged spleen.

By inhibiting these kinases, pacritinib helps to reduce the abnormal signaling, which can decrease the size of the spleen and improve symptoms related to blood cancers. Importantly, pacritinib does not significantly inhibit JAK1, which may reduce some side effects compared to other kinase inhibitors.

pacritinib

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