VX-581

VX-581 is an investigational small molecule CFTR (Cystic Fibrosis Transmembrane Conductance Regulator) corrector developed by Vertex Pharmaceuticals for the treatment of cystic fibrosis. It functions by facilitating the proper folding, processing, and trafficking of the CFTR protein to the apical cell membrane, thereby increasing the amount of functional CFTR protein available at the cell surface. This mechanism is particularly relevant for patients with the F508del mutation, where the protein is misfolded and degraded before reaching the membrane. VX-581 was evaluated in Phase 1 clinical trials as a potential component of next-generation triple-combination regimens, though it did not progress to late-stage development as Vertex prioritized other candidates like elexacaftor and vanzacaftor.