FDA OKs Ionis' Dawnzera, a new RNA-based drug for rare swelling disorder

The FDA has approved Ionis Pharmaceuticals’ drug Dawnzera (donidalorsen) to prevent life-threatening swelling attacks in people with hereditary angioedema (HAE), marking the third new HAE treatment approved in 2025.

Why it matters: Dawnzera is the first RNA-targeting drug for this condition and could offer improved efficacy, convenience, and tolerability in a crowded HAE market, potentially becoming the first-line option for patients unsatisfied with current treatments.

Backstory: Ionis is betting on a shift toward in-house commercialization with RNA-based medicines like Dawnzera. Despite strong competition, favorable trial results and patient preference could help it secure market share in an increasingly competitive field.

Big picture: HAE causes painful, sometimes life-threatening swelling attacks and affects roughly 1 in 50,000 people globally. Dawnzera is the third new HAE treatment approved in 2025, joining Kalvista’s Ekterly and CSL Behring’s Andembry.

Zoom in: In a Phase 3 trial, monthly swelling attacks dropped by 81% for Dawnzera patients vs. placebo; every other monthly dosing cut attacks by 55%. 84% of patients switching from other treatments preferred Dawnzera.

What’s next: Despite competition, analysts project Dawnzera could generate $520M in annual peak sales, driven by unmet patient needs and a price tag of $57,462 per dose.