A Study of ASTX727 in People With Malignant Peripheral Nerve Sheath Tumors (MPNST)

This study tests ASTX727, an oral medication, in patients with a rare type of nerve tumor called malignant peripheral nerve sheath tumor (MPNST) that has a specific genetic change (loss of PRC2 function). These tumors are aggressive and often don't respond well to standard chemotherapy. **You may be eligible if...** - You are at least 16 years old - You have a confirmed MPNST with PRC2 loss (shown by specific lab tests) - Your tumor has spread or cannot be surgically removed, and has progressed after at least one standard treatment - You have at least one measurable tumor on imaging - You can take oral medications - Your kidney, liver, and blood counts are within acceptable ranges **You may NOT be eligible if...** - Your tumor does not have the required PRC2 genetic change - You have not yet tried any standard systemic (whole-body) treatment - You have severe organ dysfunction - You are pregnant or unwilling to use contraception Talk to your doctor to see if this trial is right for you.