A Phase 1/2 interventional study of ION582 in Angelman Syndrome, sponsored by Ionis Pharmaceuticals, Inc.. Active, not recruiting at 11 sites in 6 countries. Open to participants aged 0 Years to 50 Years. Per ClinicalTrials.gov, last updated 2026-08-20.
Sponsored by Ionis Pharmaceuticals, Inc. · Phase 1/2, Interventional, and Treatment
The purpose of this study is to evaluate the safety and tolerability of ascending doses of ION582 administered intrathecally in participants with Angelman syndrome.
This is a Phase 1-2a, open-label study consisting of 3 parts in approximately 70 participants. Part 1 is a multiple ascending dose (MAD) study, consisting of a 13-week MAD Treatment Period and a minimum 12-week Post-MAD Follow-Up Period. Part 2 is a multi-center 49-week study where participants who completed Part 1 will receive IT bolus doses of ION582 followed by a minimum 12-week Part 2 follow up period. Part 3 extends the treatment period for participants who completed Part 2 for up to an additional 3 years followed by a 32-week post-LTE follow up period.
46 studies on the registry are indexed under Angelman Syndrome; 16 are open to participants now.
This study's enrollment of 71 is close to the median of 67 across 25 interventional studies indexed under Angelman Syndrome.
Browse Angelman Syndrome studies →Ionis Pharmaceuticals, Inc. is the lead sponsor of 116 studies on the registry; 10 are open to participants now.
Of its 48 completed or terminated interventional studies of FDA-regulated products, 21 (44%) have results posted.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Key Exclusion Criteria:
ION582 will be administered as IT injection over a period of 13 weeks, with a minimum of approximately 4 weeks between each dose administration.
Drug: ION582
ION582 will be administered as IT injection over a period of 13 weeks, with a minimum of approximately 4 weeks between each dose administration.
Drug: ION582
ION582 will be administered as IT injection over a period of 13 weeks, with a minimum of approximately 4 weeks between each dose administration.
Drug: ION582
ION582 will be administered as IT injection over a period of 13 weeks, with a minimum of approximately 4 weeks between each dose administration.
Drug: ION582
ION582 will be administered as IT injection of over a period of 13 weeks, with a minimum of approximately 4 weeks between each dose administration.
Drug: ION582
ION582 will be administered as IT injection over a period of 13 weeks, with a minimum of approximately 12 weeks between each dose administration.
Drug: ION582
ION582 will be administered as IT injection of over a period of 49 weeks, with additional dosing intervals.
Drug: ION582
ION582 will be administered as IT injection of over a period of 49 weeks, with additional dosing intervals.
Drug: ION582
ION582 will be administered as IT injection of over a period of 145 weeks, with additional dosing intervals.
Drug: ION582
ION582 will be administered as IT injection of over a period of 145 weeks, with additional dosing intervals.
Drug: ION582
ION582 will be administered by IT injection.
To evaluate the safety and tolerability of single and multiple doses of ION582 (incidence, severity, and dose-relationship of adverse effects and changes in the laboratory parameters).
The safety and tolerability of ION582 will be assessed by determining the incidence, severity, and dose relationship of adverse effects and changes in the laboratory parameters by dose.
Time frame: Part 1: Up to Week 45; Part 2: Up to Week 81
Maximum Observed Plasma Concentration (Cmax) of ION582
Time frame: Part 1: Up to Week 45; Part 2: Up to Week 81
Time to Reach Maximal Plasma Concentration (Tmax) of ION582
Time frame: Part 1: Up to Week 45; Part 2: Up to Week 81
Plasma Elimination Half-Life (t1/2λz) of ION582
Time frame: Part 1: Up to Week 45; Part 2: Up to Week 81
Concentration ION582 in CSF
Time frame: Part 1: Up to Week 13; Part 2: Up to Week 49
Plan to share: Yes — Ionis may share anonymized individual participant data, aggregated clinical data, and other types of data that support the results in this study. Data requests from qualified researchers will be considered once all three of the following criteria are met: (1) 12 months from marketing approval of the study drug in both the United States and European Union; (2) 18 months from conclusion of the study; and (3) 6 months from publication of study article. Access would be via a secure environment and is contingent upon approval of a research proposal and entry into an appropriate data use agreement. Requests to access data can be submitted via the website https://vivli.org/ourmember/ionis/.
No publications or documents are linked to this record.
This study is active, not recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Ionis Pharmaceuticals, Inc.