Pilot Study of PHOENIX Wound Matrix® Impact on Chronic DFU Wound Microbiome

The PHOENIX Wound Matrix® (PHOENIX) is a novel, fully synthetic and bioabsorbable advanced wound care device that provides a temporary microenvironment to support endogenous wound healing, allowing for the regeneration of functional, native tissue in the defect space/wound bed.

The human microbiome is a highly variable ecosystem comprising diverse microbiota of bacteria and fungi that vary more from one body site to another than from one individual to another, making it possible to define a "healthy microbiome core'' that occur frequently within different body sites. Perturbations of a body site's healthy microbiome core can disrupt the symbiotic relationship between host and associated microbes, resulting in pathogenicity and poor outcomes, such as chronic wounds.

The primary purpose of this study is to determine if PHOENIX alters the wound-associated microbiome in patients with chronic diabetic foot ulcers (DFUs).

Wound tissue and exudate samples in subjects with chronic DFUs will be collected and analyzed.

Inclusion criteria

• Subject is able and willing to provide consent, and Informed Consent Form is signed and dated prior to the initiation of any study-related activities.
• 18 years of age or older.
• Type 1 or type 2 diabetes mellitus.
• At least one DFU that meet the following criteria:

• Ulcer is diagnosed as a partial- or full-thickness DFU located on the anatomical foot, defined as a minimum of 50% of ulcer area extending distal to the medial malleolus, excluding ulcers between the toes but including those of the heel.
• Wound surface area is ≥ 1 cm2 and ≤ 25 cm2 post-debridement at the time of Study Visit 1.
• Duration of the study ulcer will be a minimum of 4 weeks and no longer than 52 weeks at the time of the Study Visit 1.
• In the case of multiple ulcers, the largest ulcer meeting the study criteria will be designated the index ulcer and the only one included in the study. If other ulcerations are present on the same leg, there must be a margin of ≥ 2 cm between the index ulcer and all other ulcers, post-debridement.
• Wagner grade 1 or 2; or Wagner grade 3 with resolved abscess or osteomyelitis (confirmed by plain x-ray, bone biopsy, magnetic resonance imaging or bone scan) or resolved joint sepsis.
• Adequate vascular perfusion of the affected limb, confirmed by normal ankle pulses (posterior tibial and dorsalis pedis arteries). If pulse character is abnormal, ABI is required. Acceptable ABI results are ≤ 6 months old and must be within the specified range to qualify: 0.8 < ABI < 1.2.
• Subject is willing and able to comply with offloading (as applicable for the location of the ulcer) or with use of appropriate footwear, as specified by the Investigator.
• Subject is willing and able to comply with the requirements of this study, as instructed by the Investigator in accordance with the study protocol.

Exclusion criteria

• Presence of signs and symptoms of infection at the index ulcer site or affected limb, including but not limited to cellulitis, osteomyelitis, excessive exudate, gangrene or deep tissue infection at the time of Study Visit 1.
• Presence of diabetes with poor metabolic control as documented with an HbA1c ≥ 12.0 within 3 months of Study Visit 1.
• Continued use of systemic antibiotics or use of systemic antibiotics within 7 days of Study Visit 1.
• Females of childbearing potential.
• Previous treatment with PHOENIX Wound Matrix®.
• Participation in another clinical trial involving a device or systematically administered investigational study drug or treatment within 30 days of Study Visit 1 date.
• Receiving or scheduled to receive a medication or treatment which, in the opinion of the Investigator, is known to interfere with, or affect, the rate and quality of wound healing.
• History of bone cancer or metastatic disease of the affected limb, radiation therapy to the foot, or chemotherapy within the 12 months of Study Visit 1 date.
• Treatment with wound dressings that include growth factors, engineered tissues, or skin substitutes within 30 days of Study Visit 1, or scheduled to receive such treatment during the Study.
• Edema or lymphedema non-responsive to the standard of care.
• Treatment with hyperbaric oxygen within 5 days of Study Visit 1 or scheduled to receive this treatment during the Study.
• History of or intercurrent illnesses or conditions (other than diabetes) that would compromise the safety of the subject, or the normal wound healing process (i.e., end stage renal disease, immunosuppression, AIDS, bleeding disorders, etc.).