Evaluating the Efficacy and Safety of Oral Ranirestat (40 and 80 mg) in Mild to Moderate Diabetic Sensorimotor Polyneuropathy

Inclusion Criteria:

- Subjects with Type 1 or Type 2, insulin-dependent or non insulin-dependent diabetes
mellitus.

- Subjects with a history of distal symmetric polyneuropathy, secondary to diabetes,
diagnosed in accordance with the American Academy of Neurology criteria.

- Female subjects, who are of non-reproductive potential (>=12 months post-menopausal or
surgically sterile) or who are using adequate contraception which includes abstinence
or double barrier methods (diaphragm and condom with spermicidal cream, intrauterine
device and condom with spermicidal cream). Male subjects with partners of
child-bearing potential must also use adequate contraception.

- Subjects must be able to read, understand, and provide written informed consent before
enrolling in the study at screening.

Exclusion Criteria:

- History of diabetic foot ulcers or lower extremity amputation.

- Diabetic amyotrophy or non-diabetic cause of lower limb neuropathy/neuropathic
symptoms.

- Clinically significant illness which, in the opinion of the investigator, would
compromise a subject's suitability to participate in the study for reasons of safety
or would confound the efficacy assessments.