A synthetic peptide that irreversibly inhibits activity of DEVD-dependent caspases (e.g., caspase-3 and caspase-7) and blocks apoptosis. The inhibitor is designed as a methyl ester to facilitate cell permeability. The product can be used for both in vitro and in vivo studies. (CAUTION: If the intended use is on purified or recombinant enzymes, esterase should be added to generate free carboxyl groups).