Aloxistatin (E64d) is an irreversible and membrane-permeable cysteine protease inhibitor. Aloxistatin was developed for treating muscular dystrophy. Open trials on 73 Duchene’s muscular dystrophy patients were conducted for 3 years at four Japanese national sanatoriums and resulted in some muscle strength improvement but the results were inconclusive and final double-blind studies did not confirm the results. Taisho has discontinued development of aloxistatin for the potential treatment of muscular dystrophy. The  trials completed through Phase 3. In animal models Aloxistatin (100 mg/kg, p.o.) strongly inhibits the cathepsin B&L activities in the skeletal muscle, heart and liver of hamsters. In spinal cord injury (SCI) rats, Aloxistatin provides neuroprotection in SCI lesion and penumbra.Aloxistatin reduces brain amyloid-β and improves memory deficits in Alzheimer's disease animal models by inhibiting cathepsin B activity.