Inclusion Criteria:
1. Males and females aged 18 or older.
2. Subject is willing to sign informed consent and participate in all procedures with follow up evaluations as necessary to complete the study.
3. Study ulcer is diabetic in origin, located on the foot or below the malleolus with ulcer extending through the dermis but not into tendon, muscle or bone (UT Grade 1A).
4. Study ulcer size is a minimum of 2 cm2 and maximum 25 cm2 after the run-in period.
5. Study ulcer has been present for a minimum of 4 weeks before enrollment and less than 1 year old, with documented failure of prior treatment to heal the wound.
6. Study ulcer has been offloaded for at least 14 days prior to randomization.
7. A two-week run-in period will precede enrollment in the trial to document the indolent nature of the subjects selected; healing rate is not to be > 40% during this period.
8. Subject does not exhibit clinical signs / symptoms of infection upon gross observation or have been diagnosed with an active infection at time of screening.
9. Subject has adequate control of diabetes demonstrated by Hemoglobin A1c < 12% within 90 days of screening.
10. Subject has adequate circulation to the affected extremity, as demonstrated by one of the following within the past 60 days of the first screening visit:
- Dorsal transcutaneous oxygen measurements (TCOM) ≥ 30mmHg.
- Ankle-Brachial Index with results of ≥ 0.8 and ≤ 1.5 or had past intervention.
Exclusion Criteria:
1. Study ulcer wound surface is area greater than 25 cm2.
2. Study ulcer has > 40% wound healing during the 14 days screening period.
3. Subject has a known history of poor compliance with medical treatments.
4. Subject is presently participating in another clinical trial.
5. Subject has a known or suspected local malignancy to the Study diabetic ulcer, or systemic malignancy.
6. Subject has been diagnosed with autoimmune connective tissues diseases.
7. Subject has received graft material or topical growth factors on the study ulcer within the previous 30 days.
8. Subject has received application of topical steroids on the study ulcer surface within the previous 30 days.
9. Subject is pregnant or breast feeding.
10. Subject is on dialysis.
11. Subject is taking medications that are considered immune system modulators or cytotoxic chemotherapies.
12. Subject cannot be on systemic antibiotics prior to randomization, however, during the treatment phase infection management may include systemic antibiotics if in conjunction with debridement.
13. Subject has a known allergy to ingredients/components of AC5.
14. Subject has osteomyelitis, and/or bony prominences present in the wound.
15. Subject has ulcer probing to bone and tendon. (UT Grade II or III A-D).
16. Subject is unable to comply with planned study procedures and treatments.