Argo Biopharmaceutical (Argo Biopharma), a clinical-stage small interfering RNA (siRNA) therapeutics company, has been selected to present late-breaking Phase II interim data for BW-20805 at the American Academy of Allergy, Asthma and Immunology (AAAAI) 2026 Annual Meeting, scheduled for February 27 to March 2, 2026.

BW-20805 is an investigational siRNA therapy designed to target and significantly inhibit prekallikrein (PKK), a validated therapeutic target for Hereditary Angioedema (HAE). By suppressing PKK levels, the therapy aims to prevent HAE attacks with a long-lasting prophylactic effect.

The interim findings come from an ongoing open-label Phase II study in adults with HAE. The results, selected as a late-breaking abstract titled ‘Significant HAE Attack Reduction with BW-20805, a Long-Acting Prophylactic Injection – An Ongoing Phase II Study in Adults with Hereditary Angioedema’, demonstrated marked reductions in plasma PKK levels and clinically meaningful, time-normalised reductions in HAE attack rates.

According to the company, BW-20805 showed sustained PKK suppression alongside a favorable safety and tolerability profile across all dose levels evaluated. The data support further investigation of a potential once-every-six-months (Q6M) dosing regimen aimed at addressing long-term prophylactic needs in HAE patients.

Dr Dongxu Shu, Co-founder and Chief Executive Officer of Argo Biopharma, said the late-breaking abstract selection underscores the growing body of evidence supporting BW-20805 and highlights its potential to deliver sustained reductions in HAE attack rates with a well-tolerated safety profile.

Hereditary angioedema is a rare genetic disorder characterised by recurrent episodes of severe swelling, which can be life-threatening if it affects the airway. Long-acting preventive therapies remain a key unmet need for many patients.