News•Mar 17, 2026
ION717 Trial Re-Opens with 3rd Dosing Regimen
Ionis Pharmaceuticals announced that its Phase 1/2a PrProfile trial of ION717, the first PrP‑lowering antisense oligonucleotide for symptomatic prion disease, has reopened with a third dosing regimen. The study, which enrolled 56 patients in 2024, will now recruit at three active sites—Cleveland, Tokyo, and Yamaguchi—and will test a likely higher dose in an open‑label format without a placebo arm. Preliminary safety and tolerability data were encouraging, prompting the expansion, and the primary completion date has been pushed to February 2027. The new cohort will also join the ongoing open‑label extension for earlier participants.
