SHANGHAI, CHINA and BOSTON, USA – September 15 , 2025—Argo Biopharmaceutical Co., Ltd. (Argo Biopharma), a clinical-stage small interfering RNA (siRNA) therapeutics company, today announced that the National Medical Products Administration of China (NMPA) has granted Investigational New Drug (IND) approval for a Phase II clinical trial of BW-40202, an investigational siRNA therapy targeting complement factor B (CFB) for the treatment of paroxysmal nocturnal hemoglobinuria (PNH) and other complement-mediated diseases. The study is expected to commence in January 2026. BW-40202 is also being evaluated in a Phase I study as a potential treatment for IgA Nephropathy (IgAN). The Phase I/IIa IND approval was obtained from the NMPA in China in June 2025.

“The IND approval for BW-40202 is an important milestone in our mission to redefine treatment for patients with PNH. This achievement underscores our innovative approach in targeting the complement system and moves us one step closer to delivering a potential new, targeted therapy to patients who need more treatment options. We are excited to initiate clinical studies and unlock the full potential of BW-40202 for PNH and other complement alternative pathway (CAP)-mediated diseases,” said Dr. Dongxu Shu, co-founder and CEO of Argo Biopharma.

BW-40202 is an siRNA therapeutic that targets CFB mRNA in the liver. It utilizes an RNA interference (RNAi) mechanism to suppress CFB expression, thereby reducing serum CFB protein levels and inhibiting CAP activity. In preclinical studies, BW-40202 demonstrated excellent purity and stability, with significant and durable suppression of serum CFB protein, effective inhibition of CAP activity, and a favorable safety profile. BW-40202 also demonstrated excellent pharmacological activity, significantly reducing serum CFB protein levels and effectively inhibiting CAP activity, with long-lasting effects and a favorable safety profile.

About Paroxysmal Nocturnal Hemoglobinuria (PNH)

Paroxysmal Nocturnal Hemoglobinuria (PNH) is a blood disorder characterized by complement-mediated red blood cell destruction (hemolysis), blood clot formation, and impaired bone marrow function. Globally, it is believed that approximately 10 to 20 individuals per million are living with PNH¹. Patients may experience a range of symptoms, including severe anemia, blood clots, hemoglobinuria, chronic kidney disease, and pulmonary hypertension. Thrombosis remains the most life-threatening complication, responsible for 40% to 67% of PNH-related deaths, significantly reducing both quality of life and life expectancy. siRNA therapies offer precise targeting, longer-lasting efficacy, reduced dosing frequency, and improved safety and convenience, which is a promising new approach with the potential to deliver more effective, durable, safer, and more manageable treatment options.

About Argo Biopharma

Argo Biopharma is a clinical-stage biotechnology company committed to developing next-generation RNAi therapeutics to provide better treatment options for patients worldwide. The company has established a robust and diverse pipeline of RNAi molecule candidates targeting a wide range of indications, including cardiovascular diseases, viral infections, metabolic conditions, and specialty/rare diseases. Currently, Argo Biopharma has six RNAi candidates in clinical development.

For more information, visit www.argobiopharma.com.

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References:

1. Schrezenmeier, H., et al. (2020). Baseline clinical characteristics and disease burden in patients with paroxysmal nocturnal hemoglobinuria (PNH): updated analysis from the International PNH Registry. Annals of Hematology, 99, 1505–1514.