An Extension Study of Donidalorsen (IONIS-PKK-LRx) in Participants With Hereditary Angioedema

Inclusion Criteria

• •1. Satisfactory completion of ISIS 721744-CS2 (index study) through Week 17 with an acceptable safety and tolerability profile, per Sponsor and Investigator judgement
• •2. Able and willing to participate in a 64-week study
• •3. Females must be non-pregnant, non-lactating and either surgically sterile or post-menopausal
• •4. Males must be surgically sterile or abstinent\* or if engaged in sexual relations with a female of child-bearing potential, participant is utilizing an acceptable contraceptive method
• •5. Participants must have access to, and the ability to use, ≥ 1 acute medication(s) (e.g., plasma-derived or recombinant C1- inhibitor (C1-INH) concentrate or a bradykinin-2 \[BK-2\] antagonist) to treat angioedema attacks