Q-VD-OPh is an irreversible pan-caspase inhibitor with potent antiapoptotic properties; inhibits caspase 7 with IC50 of 48 nM and 25-400 nM for other caspases including caspase 1, 3, 8, 9, 10, and 12. Q-VD-OPha is able to cross the blood-brain barrier.