Why Shares of Rain Oncology Are Plummeting Today

Shares of Rain Oncology (NASDAQ: RAIN) were down 87% Monday afternoon after the precision oncology company released top-line results for its lead therapy, milademetan, to treat dedifferentiated liposarcoma, a type of cancer affecting fatty tissue, usually in the arms and legs. Rain said that milademetan, an inhibitor of the MDM2-p53 complex that reactivates p53, a known tumor inhibitor, taken orally, did not meet its primary endpoint of efficacy in a phase 3 trial to treat patients with dedifferentiated (DD) liposarcoma (LPS). Based on the disappointing results, Rain said it does not plan to pursue further development of the therapy to treat DD LPS.