The trial is testing the product as a potential treatment for synovial sarcoma, a cancer that appears in soft tissue, and SMARCB1-deleted tumors. Foghorn halted the trial after a “grade 4 QTc prolongation event in a synovial sarcoma patient at the second highest dose,” meaning the cancer patient’s heartbeat slowed or took longer than normal to contract and relax.
“[The] FDA placed the study on partial clinical hold in the United States, while allowing patients currently enrolled and benefiting from therapy to continue dosing and to remain on FHD-609,” Foghorn said, adding it “is not at this time planning to pursue a dose expansion study independently.”
