A Study to Assess the Long-Term Safety and Efficacy of Donidalorsen in the Prophylactic Treatment of Hereditary Angioedema (HAE)

This is an interventional treatment trial for Hereditary Angioedema focused on measuring HAE Read More

Inclusion Criteria

1. Participants and, as applicable, legally authorized representatives (i.e., parent(s)/legal guardian), must provide written and signed informed consent form (ICF).
2. Participants must have access to, and the ability to use, ≥ 1 acute medication(s) (e.g., plasma-derived or recombinant C1-INH concentrate or a bradykinin receptor (BK) 2-receptor antagonist) to treat angioedema attacks Open-Label Extension Participants ONLY
3. Satisfactory completion of ISIS 721744-CS5 (randomized placebo-controlled index study) through Week 25 or participants who are allowed to exit ISIS 721744-CS5 study per protocol with an acceptable safety and tolerability profile New (not previously on donidalorsen) Participants ONLY
4. Participants must be aged ≥ 12 years at the time of informed consent and, as applicable, assent
5. Participants must have a documented diagnosis of HAE-1/HAE-2
6. Participants must be on a stable dose (≥ 12 weeks) of prophylaxis treatment with lanadelumab or berotralstat or SC C1-esterase inhibitor prior to the Screening Period Exclusion Criteria

Open-Label Extension Participants:

1. Have any new condition or worsening of an existing condition or change or anticipated change in medication New (not previously on donidalorsen) Participants ONLY
2. Concurrent diagnosis of any other type of recurrent angioedema, including acquired, idiopathic angioedema or HAE with normal C1-INH (also known as HAE Type III)
3. Anticipated change in the use of concurrent androgen or tranexamic acid prophylaxis used to prevent angioedema attacks
4. Any clinically-significant abnormalities in screening laboratory values
5. Malignancy within 5 years of Screening, except for non-melanoma skin cancers, cervical in situ carcinoma, breast ductal carcinoma in situ, or stage 1 prostate carcinoma that has been successfully treated.
6. Hypersensitivity to the active substance (donidalorsen) or to any of the excipients
7. Treatment with another investigational drug (non-oligonucleotide) or biological agent within 1 month of Screening or 5 half-lives of investigational agent, whichever is longer
8. Recent history of, or current drug or alcohol abuse
9. Participated in a prior donidalorsen study

10. Exposure to any of the following medications:

    1. Angiotensin-converting enzyme (ACE) inhibitors or any estrogen containing medications with systemic absorption
    2. Oligonucleotides (including small interfering ribonucleic acid [siRNA]) within 4 months of Screening if single dose received, or within 12 months of Screening if multiple doses received. This exclusion does not apply to vaccines