Business Wire·Nov 12, 2026, 10:00 AM ET

Ionis presents new long-term data supporting durable efficacy and disease control with DAWNZERA® (donidalorsen) at ACAAI 2026 Annual Meeting

Ionis Pharmaceuticals announced two-year long-term efficacy & safety data for DAWNZERA (donidalorsen) at the 2026 ACAAI Annual Scientific Meeting.
Patients switching from prior long-term prophylactic therapies maintained a 71% reduction in HAE attack rates over two years.
Patients continuing from the Phase 3 OASIS-HAE trial achieved a 95% overall reduction in HAE attack rates across both dosing groups.
Treatment efficacy was consistent regardless of dosing frequency every four weeks or every eight weeks.
In the open-label extension cohort, 84% of patients remained in the study after two years with 83 participants analyzed.
In the switch cohort, 80% of patients remained after two years with 64 participants analyzed.
No new safety signals were observed, with most treatment-emergent adverse events being mild or moderate & no serious events related to DAWNZERA.
Common adverse reactions include injection site reactions, upper respiratory tract infection, urinary tract infection, & abdominal discomfort.
DAWNZERA is contraindicated in patients with a history of serious hypersensitivity reactions or anaphylaxis to donidalorsen or its excipients.
The medicine targets plasma prekallikrein to prevent hereditary angioedema attacks in adult & pediatric patients aged 12 years & older.