BOSTON — Astria Therapeutics has announced promising initial results from its ALPHA-SOLAR long-term open-label trial evaluating navenibart in patients with hereditary angioedema (HAE), reinforcing the drug’s potential as a market leader in the treatment of the rare genetic disorder. The data, presented at the European Academy of Allergy and Clinical Immunology (EAACI) Annual Congress, show substantial and sustained reductions in HAE attack rates with both three-month and six-month dosing schedules.
Navenibart, a monoclonal antibody targeting plasma kallikrein, demonstrated a 92% mean reduction in monthly HAE attacks across the 16 patients who transitioned into the ALPHA-SOLAR study from an earlier Phase 1b/2 trial. The Q3M (every three months) dosing group showed a 95% mean reduction, while the Q6M (every six months) arm achieved an 86% reduction. All patients remain on therapy, and half experienced complete attack freedom over a six-month period—the longest follow-up reported to date.
“This is a pivotal moment in our development of navenibart,” said Dr. Christopher Morabito, Chief Medical Officer at Astria. “These results reaffirm the best-in-class profile we observed in the earlier ALPHA-STAR trial and support the potential of infrequent dosing—just two or four times per year—to protect patients from debilitating attacks with minimal treatment burden.”
The drug also maintained a favorable safety profile. No serious or severe treatment-related adverse events were reported, and the only treatment-related reactions were mild and self-resolving. The absence of pain at injection sites and no patient discontinuations further highlight the therapy’s tolerability.
Dr. William Yang, Chair of Ottawa Allergy Research Corporation and Red Maple Trials Inc., emphasized the significance of the findings for patient quality of life. “For HAE patients, less frequent dosing that still provides strong, lasting protection could be transformative. These results suggest patients may spend more time living their lives and less time managing their disease.”
All 16 participants in the ALPHA-SOLAR study were previously enrolled in ALPHA-STAR and opted to continue treatment with navenibart. Follow-up times averaged between 8 and 11 months depending on the dosing arm. The strong consistency between earlier and current trial results adds further support to navenibart’s long-term efficacy.
Astria initiated its Phase 3 ALPHA-ORBIT trial earlier this year to further evaluate the Q3M and Q6M regimens in a larger population. The trial is actively enrolling patients and is listed under NCT06842823 at clinicaltrials.gov.
Additional details from the ALPHA-SOLAR study are available in a poster presentation at the EAACI Congress and through Astria’s website.
