Summary

Ruxolitinib is an inhibitor of the cytosolic tyrosine kinase Janus kinase (JAK) family of proteins (JAK1/2), which is widely used to treat various myeloid neoplasms that are characterized by constant activation of the JAK-STAT signaling pathway.

Many side effects are associated with ruxolitinib, including anemia, thrombocytopenia, increased rate of infections (especially herpes zoster), and mild hypercalcemia noted in 15.4% of patients [1]. The possible mechanism causing hypercalcemia may involve altered bone and mineral metabolism with secondary hyperparathyroidism, as described for other kinase inhibitors [2].