Autologous Platelet-Rich Plasma Therapy in the Treatment of Pyoderma Gangrenosum

1. Have given written informed consent before participating in any study-specific activity.
2. Have a clinical diagnosis of classic PG as determined by the principal investigator based on results from clinical, histological, and laboratory assessments.
3. Have at least 2 PG ulcer characterized by 'item a' AND 3/5 features in 'item b' OR 2/5 features in 'item b' with support from one of the conditions listed in c. a. Stable or increasing size within 2 months preceding screening by patient report or documentation. b. Features such as violaceous border, undermining, cribriform scarring, pustules, peristomal location. c. Identifiable secondary systemic condition, such as IBD, arthritis, MGUS, noncancerous hematologic disease, streptococcal carriage, levamisole-tainted cocaine, Bruton's agammaglobulinemia.
4. Have at least two PG target ulcers that have an area = 2 cm2 and = 200 cm2 at screening.
5. Age at least 18 years at screening.
6. A negative pregnancy test (for females of childbearing potential) at both screening and at Day 0.
7. PARACELSUS Score for pyoderma gangrenosum of 10 or greater.

Exclusion Criteria:

1. Any condition (e.g., psychiatric illness, severe alcoholism, or drug abuse) or situation that may compromise the ability of the subject to give written informed consent, may put the subject at significant risk, may jeopardize the subject's safety after treatment, may confound the study results, or may interfere significantly with the subject's participation in the study.
2. History of malignancy within 2 years of screening other than carcinoma in situ of the cervix or adequately treated, non-metastatic, squamous, or basal cell carcinoma of the skin.
3. History of seropositivity for HIV antibody; active or carrier status of hepatitis B [surface antigen (HBsAg) positive, or core antibody (anti-HBc) positive with negative surface antibody]; active hepatitis C (i.e., not treated or not cleared spontaneously, as confirmed by HCV PCR).
4. Patients with hemodynamic instability, bleeding disorders, and/or platelet dysfunction syndrome.
5. A complete blood count will be performed for each participant at the beginning of the study and those with serum hemoglobin concentration \<11 g/ dL or hematocrit \<34% or platelet count\<1, 00000/ml will be excluded from the study.
6. Patients with uncontrolled secondary systemic disease in the opinion of the investigator.
7. Systemic infection or active local infection requiring oral antibiotics within 2 weeks of Day 0.

8. History of the following treatments:

   1. Patients taking anticoagulant medication.
   2. Changes (addition, discontinuation, or changes in dose) in immunosuppressive medication (including cyclosporine, azathioprine, methotrexate, mycophenolate mofetil, apremilast, dapsone, or corticosteroids) and biologics (Anti-TNF or other biologic therapies) within 2 months of Day 0.
   3. Systemic corticosteroids > 20 mg per day (prednisone or prednisone equivalent) within 8 weeks of Day 0 or change in dose within 4 weeks of Day 0. Steroids may be tapered (although not increased above the Day 0 dose) during the trial as determined by the principal investigator.
   4. Intralesional corticosteroids within 8 weeks of day 0; topical immunomodulators are also not permitted.
   5. Systemic antibiotics within 2 weeks of Day 0.
   6. Hyperbaric treatment within 4 weeks of Day 0.
   7. Investigational drug or investigational device within 4 weeks of Day 0.
   8. Other treatments not described above should be maintained at a stable dose and frequency throughout the study as best as possible.
9. Major, general surgery within 3 months of screening, or anticipated general surgery during the study period.
10. Pregnancy plans to become pregnant during the study, delivery within 3 months of screening, or breastfeeding.
11. If previous use of cyclosporine or systemic corticosteroids, failure to have any stabilization/response is exclusionary. This potentially indicates the disease is not PG.