GSK429286A is a potent and selective Rho-Kinase (ROCK) inhibitor (IC₅₀ = 14 and 63 nM for ROCK1 and ROCK2, respectively). ROCK inhibitors have been found to prevent apoptosis, as well as enhance the survival and cloning efficiency of dissociated human embryonic stem (ES) cells without affecting their self-renewal properties or pluripotency.