Prion Disease is currently an invariably fatal condition without treatment or cure. Despite multiple prior treatment studies, including quinacrine, doxycycline, and pentosan polysulfate, no investigational treatments have benefited patients with prion disease. However, new treatments are currently being investigated. This site will be regularly updated with available treatment trial information for prion disease.
**Please Note: This trial has reopened for enrollment in the U.S.**
Click to read the 03/17/2026 Community Statement from Ionis Pharmaceuticals.
This is a first-in-human, randomized, multicenter study in participants with prion disease. Eligible participants will receive ION717 and a placebo. The order of doses will be randomized and blinded to participants, study sites, and the Sponsor. The study will consist of a screening period of up to 6 weeks, a 24-week double-blind treatment period, and a 36-week post-treatment period. Multiple dose levels will be tested.
Please click here for the complete study details on the ClinicalTrials.gov page.
**This trial is open for enrollment in the U.S.**
This is a first-in-human, open-label, single ascending dose study in participants with prion disease. The study will consist of a screening period of up to 2 weeks, administration of a single intrathecal dose of PrP-siRNA, and a 24-week follow-up period. Multiple dose levels will be tested. This trial also includes an observational arm in which participants will not receive the investigational drug, and will be followed for an 8-week period after baseline.
Please click here for the complete study details on the ClinicalTrials.gov page.