ASP 8825 - Study in Patients With Painful Diabetic Polyneuropathy

Inclusion Criteria: * Subjects aged 20 - 79 years * Diabetes mellitus patients with diabetic polyneuropathy who have pain symptom for 26 weeks prior to the study * Subjects who are compliant with diary completion Exclusion Criteria: * Subjects who have pain from other diseases at the evaluating site * Subjects who have nerve diseases at the evaluating site * Subjects with foot ulcer or gangrene