Arrowhead Pharmaceuticals, Inc. announced that it has dosed the first subjects in a Phase 1/2a clinical trial (NCT06209177) of ARO-CFB, the company?s investigational RNA interference (RNAi) therapeutic, in up to 66 healthy volunteers and patients with complement mediated kidney disease. In preclinical studies, ARO-CFB achieved deep and durable reductions in liver production of complement factor B, which is involved in alternative complement pathway activation and associated with pathogenesis of diseases involving complement activation. ARO-CFB is second clinical program designed to address diseases associated with activation of the complement pathway, the first being ARO-C3, Phase 1 program targeting complement component 3. The company look forward to further progressing both programs to investigate whether these candidates can address the substantial unmet medical need that remains in the treatment of multiple complement mediated diseases.

ARO-CFB is designed to reduce hepatic expression of complement factor B (CFB), which plays an important regulatory role in amplifying complement alternative pathway activation and has been identified as a promising therapeutic target. ARO-CFB is being developed as a potential treatment for complement mediated kidney diseases such as immunoglobulin A nephropathy (IgAN), which is the most common glomerular disease worldwide and carries a high lifetime risk of progression to end-stage renal disease. Additionally, ARO-CFB may have clinical applications in non-renal diseases involving complement activation.