Avapritinib in the Treatment of Systemic Mastocytosis: an Update

Purpose of Review Patients with systemic mastocytosis, a dangerous and rare myeloid neoplasm, have long had few therapies available to them and, historically, rarely achieved from significant disease control. However, research and translational developments over the last decade have led to promising new options for disease management. In this review, we briefly outline the history of treatment for systemic mastocytosis and subsequently focus on the clinical development and potential applications of avapritinib (previously known as BLU-285), a potent and selective oral inhibitor of the tyrosine kinase most commonly mutated in this condition. Recent Findings Phase I data and recent phase II data have demonstrated both safety and efficacy of this agent used as monotherapy, even in patients who have progressed on other targeted therapy. Studies to date have focused on patients with the most aggressive disease, but new trials in indolent mastocytosis are accruing currently. Over the next several years, one may anticipate finalized, peer-reviewed, and formally published data for this agent in both advanced systemic and indolent mastocytosis. Evidence from these early studies will also likely highlight where more research is needed.