EST-101

EST-101 is an investigational adeno-associated virus (AAV)-delivered gene therapy designed to treat autosomal dominant polycystic kidney disease (ADPKD) caused by mutations in the PKD1 gene. Developed by Estuary Biotherapeutics, EST-101 delivers a compact, functional region derived from the polycystin-1 (PC1) protein, which is typically reduced or dysfunctional in patients with PKD1 mutations. Unlike the full-length PKD1 gene, which is too large to package into standard AAV vectors, this specific functional fragment can be successfully packaged and delivered. EST-101 is designed for potentially one-time, local administration directly to the kidneys to transduce kidney epithelial cells, aiming to restore polycystin protein levels across the nephron and potentially halt or reverse cystic disease. It is anticipated to enter clinical trials in 2028.