This is a phase 2 double-blind clinical study to evaluate the efficacy and Safety of ALLO-ASC-SHEET in subjects with Diabetic Foot Ulcers, compared to placebo therapy.

1. Active Group: ALLO-ASC-SHEET
2. Control Group: Hydrogel SHEET (vehicle control)
3. Study Type: Interventional
4. Study Design: Randomized, Comparator-controlled, Double-blind, multi-center study.

Inclusion Criteria:

1. Male or female subjects between 18 and 80 years of age.

2. Diagnosed with Type I or Type II diabetics and has diabetic foot ulcers for longer than 4 weeks at the screening visit.

3. Foot ulcer located in the instep, border or sole of the foot, with ulcer size between 1 cm2 and 15 cm2.

4. Ulcer graded I by Wagner grade, and extended to skin, subcutaneous tissue, but without exposure of muscle, tendon, bone or joint capsule.

5. Ulcer is free of necrotic debris, exhibits no signs of clinical infection.

6. Ulcer area blood circulation meets one of the following criteria

   • A. Blood vessels around the ulcer detected by Doppler Test
   • B. range of Ankle Brachial Index(ABI) was > 0.7 to < 1.3
   • C. Transcutaneous oxygen pressure, (TcPO2) > 30 mmHg.

7. Is able to give written informed consent prior to study start and to comply with the study requirements.

Exclusion Criteria:

1. Ulcer is of non-diabetic pathophysiology.
2. The ulcer has increased or decreased in size by ≥ 30% during the week after the Screening Visit.
3. Is Human Immunodeficiency Virus (HIV) positive?
4. Have severe hepatic deficiencies.
5. Have a glycated hemoglobin A1c (HbA1c) level of > 10%.
6. Have allergic or hypersensitive reaction to bovine-derived proteins or fibrin glue.
7. Require intravenous (IV) antibiotics to treat the target wound infection.
8. Have severe renal failure including subject on renal dialysis.
9. Pregnant or breast-feeding.
10. Is unwilling to use an "effective" method of contraception during the study.
11. Have evidence of current infection including pus drainage from the wound site.
12. Have a clinically relevant history of alcohol or drugs abuse.
13. Have postprandial blood sugar > 350 mg/dl.
14. Is not able to understand the objective of this study or to comply with the study requirements.
15. Is considered by the investigator to have a significant disease which might have impacted the study.
16. Is considered not suitable for the study by investigator.
17. Have a history of malignancy within the last five years (except basal cell carcinoam in situ).
18. Is currently or were enrolled in another clinical study within 60 days of screening.
19. Have undergone wound treatments with growth factors, dermal substitutes, or other biological therapies within the last 30 days.
20. Is receiving oral or parenteral corticosteroids, immunosuppressive, or cytotoxic agents with unstable dose prior to 4 weeks from screening.
21. Cannot maintain off-loading process
22. Panel reactive antibody (PRA) levels ≥ 20%

Double-Blind