ART5

ART5 is an investigational antisense oligonucleotide (ASO) developed by Arnatar Therapeutics for the treatment of Autosomal Dominant Polycystic Kidney Disease (ADPKD). Developed using the company's proprietary ACT-UP1 platform (part of the DARGER™ dual-modality system), ART5 is designed to directly enhance the translation of PKD1 mRNA, thereby increasing the expression of the polycystin-1 (PC1) protein. This mechanism addresses the underlying genetic deficiency characteristic of ADPKD, where reduced levels of functional PC1 lead to cyst growth and kidney failure. Preclinical data presented at ASN Kidney Week 2025 demonstrated that ART5 can achieve up to a two-fold increase in PC1 expression across human, mouse, and non-human primate cells. In patient-derived cells, this upregulation was associated with disease-modifying functional improvements, including reduced cAMP levels, decreased cell proliferation, and inhibited cyst formation. The program is currently in the IND-enabling stage of development.