Ionis Pharmaceuticals, Inc. has announced the approval of Dawnzera™ (donidalorsen) by the U.S. Food and Drug Administration (FDA) for the prophylactic treatment of hereditary angioedema (HAE) in adult and pediatric patients aged 12 years and older. Dawnzera is the first and only RNA-targeted medicine approved for HAE, targeting plasma prekallikrein (pkk), a key protein associated with acute HAE attacks.
The approval is based on positive results from the phase 3 global, multicenter, randomized, double-blind, placebo-controlled OASIS-HAE study. Dawnzera administered once every four weeks (q4w) significantly reduced the monthly HAE attack rate by 81% compared to placebo over 24 weeks. The mean attack rate reduction increased to 87% when measured from the second dose, a key secondary endpoint. Additionally, Dawnzera q4w reduced moderate-to-severe HAE attacks by approximately 90% over 24 weeks when measured from the second dose.
Furthermore, the ongoing OASISplus open-label extension (OLE) study demonstrated that Dawnzera q8w had a similar effect as q4w over time, with a 94% total mean attack rate reduction from baseline across both dosing groups after one year in the OLE. In a switch cohort evaluating Dawnzera q4w in patients previously treated with other prophylactic therapies, switching to Dawnzera reduced the mean HAE attack rate by 62% from prior treatment over 16 weeks, with 84% of patients preferring Dawnzera over their prior prophylactic treatment.
In terms of safety and tolerability, Dawnzera demonstrated a favorable profile, with the most common adverse reactions being injection site reactions, upper respiratory tract infection, urinary tract infection, and abdominal discomfort.
The company is dedicated to supporting the HAE community and will offer a suite of services through Ionis Every Step™, including patient education support, assistance with the insurance approval process, information on affordability programs, access to the Dawnzera direct digital companion, and ongoing services and resources to help patients stay on track.
Dawnzera will be available in the U.S. in the coming days, and Ionis Pharmaceuticals, Inc. is expecting this approval to be a significant advancement in providing improved treatment options for people living with HAE. The market has reacted to these announcements by moving the company's shares 0.36% to a price of $42.9651. If you want to know more, read the company's complete 8-K report here.
