A Phase 3 interventional study of Donidalorsen in Hereditary Angioedema (HAE), sponsored by Ionis Pharmaceuticals, Inc.. Recruiting at 18 sites in 5 countries. Open to participants aged 2 Years to 11 Years. Per ClinicalTrials.gov, last updated 2026-11-02.
Sponsored by Ionis Pharmaceuticals, Inc. · Phase 3, Interventional, and Treatment
The purpose of this study is to evaluate the safety, tolerability and pharmacokinetics of donidalorsen in pediatric participants with hereditary angioedema (HAE) Type I (HAE-1) or Type II (HAE-2).
This is an open-label study to evaluate the safety, efficacy, and pharmacokinetics (PK) and pharmacodynamics (PD) of donidalorsen in pediatric participants age 2 to less than 12 years old with HAE Type I (HAE-1) or Type II (HAE-2). The study consists of 3 parts: 1) a 3-month Screening Period, 2) a one-year Treatment Period, and 3) a 3-month Post-Treatment Period.
171 studies on the registry are indexed under Angioedemas, Hereditary; 24 are open to participants now.
This study's planned enrollment of 20 is below the median of 48 across 116 interventional studies indexed under Angioedemas, Hereditary.
Browse Angioedemas, Hereditary studies →Ionis Pharmaceuticals, Inc. is the lead sponsor of 118 studies on the registry; 10 are open to participants now.
Of its 49 completed or terminated interventional studies of FDA-regulated products, 22 (45%) have results posted.
Counted across the registry records on this site, refreshed daily.
Key Inclusion Criteria:
Documented diagnosis of HAE-1/HAE-2 based upon both of the following:
Key Exclusion Criteria:
Note: Other protocol-specified inclusion/exclusion criteria may apply.
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participant weighing 9 kilograms (kg) to less than (\<)26 kg, will be administered donidalorsen over the period of one year.
Drug: Donidalorsen
Participant weighing greater than or equal to (≥)26 kg to \<41 kg, will be administered donidalorsen over the period of one year.
Drug: Donidalorsen
Participant weighing ≥41kg, will receive donidalorsen over the period of one year.
Drug: Donidalorsen
Donidalorsen will be administered by subcutaneous (SC) injection.
Also known as: ISIS 721744, IONIS-PKK-LRx
Number of Participants with Treatment Emergent Adverse Events (TEAEs)
Time frame: over the period of approximately 17 months
Maximum Plasma Concentration (Cmax) of Donidalorsen
Time frame: over the period of approximately 17 months
Maximum Time to Reach Cmax (Tmax) of Donidalorsen
Time frame: over the period of approximately 17 months
Trough Plasma Concentration (Ctrough) of Donidalorsen
Time frame: over the period of approximately 17 months
Time-Normalized Number of Investigator-Confirmed HAE Attacks (per Month)
Time frame: over the period of 12 months
Percentage of Investigator-Confirmed HAE Attack-free Participants
Time frame: over the period of 12 months
Time-Normalized Number of Moderate or Severe Investigator-Confirmed HAE Attacks (per Month)
Time frame: over the period of 12 months
Number of Participants with a Clinical Response Defined as a ≥ 50 Percent (%), ≥ 70% and ≥ 90% Reduction from Baseline in Investigator-Confirmed HAE Attack Rate
Time frame: over the period of 12 months
Time-Normalized Number of Investigator-Confirmed HAE Attacks Requiring Rescue Treatment
Time frame: over the period of 12 months
Change From Baseline in Prekallikrein (PKK) Levels in Plasma
Time frame: over the period of 12 months
Percent Change From Baseline in PKK Levels in Plasma
Time frame: over the period of 12 months
Changes in Pediatrics Quality of Life (PedsQL) Scores for Participants
Time frame: over the period of 12 months
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/.
Data sharing details ↗ · vivli.org
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Studies of the drug tested here: Donidalorsen