Blueprint Medicines Corporation announced that the U.S. Food and Drug Administration (FDA) has accepted the company's supplemental new drug application for AYVAKIT(R) (avapritinib) for the treatment of adults with indolent systemic mastocytosis (SM). The FDA granted priority review with an action date of May 22, 2023 under the Prescription Drug User Fee Act (PDUFA). This regulatory application is based on results from the global PIONEER trial, the
randomized, placebo- controlled study ever conducted in indolent SM. The FDA previously granted breakthrough therapy designation to AYVAKIT for the treatment of moderate to severe indolent SM. AYVAKIT was designed to potently and selectively inhibit D816V mutant KIT, the primary underlying cause of SM.