Autologous Peripheral Blood Mononuclear Cells in Diabetic Foot Patients With No-option Critical Limb Ischemia
Condition: Critical Limb Ischemia; Diabetic Foot
MeSH terms: Diabetic Foot; Chronic Limb-Threatening Ischemia; Ischemia
Study type: Interventional

Summary: 
      The objective of this trial is to determine whether PBMNCs in diabetic patients with
      critical, non revascularizable limb ischemia can prevent major amputation and affect
      mortality and healing.
    

Detailed description: 
      This is an interventional study with historical control group carried out to assess as
      primary outcome major amputations, overall mortality, number of healed patients in group of
      patients who received repetitive intra-muscular implant of PBMNCs (3 times; 4-week interval)
      in comparison to a historical internal control group with a 1:1 case-control ratio. Secondary
      outcomes are TCPO2, healing time and rest pain.

      No-option critical limb ischaemia is defined by evidence of no run-off pedal vessels, failure
      after several percutaneous intervention and no longer possible re-intervention, failure after
      infra-genicular bypass grafting, no-walking capacity with severe comorbidities unfit for
      surgical or endovascular procedures.

      Inclusion criteria are: a) ulcers with inadequate perfusion, as indicated by a transcutaneous
      oxygen pressure value (TcpO2) <30 mmHg; b) ulcers with grade I or II or III and stage C as
      defined by the Texas University Classification System or W1,2,3 - I 3 - FI 0,1 as defined by
      the WiFI Classification System c) not eligible for angioplasty or vascular surgery or
      following failed revascularization; d) possibility to save foot support.

      Exclusion criteria are: a) lesion site above the tibial-tarsal joint; b) moderate or severe
      infection according by the WiFI classification system; c) NYHA class IV; d) Anemia
      (Hb<8g/dl); e) coagulation disorder/thrombocytopenia (PLT< 50,000 per microliter); f) active
      cancer/leukemia or lymphoma hematological disease.

      Standard of care in both groups includes: diabetes control maximization by the diabetologist,
      comprehensive foot assessment by the nurse together with the diabetologist, including
      determination of vibration perception threshold, 10-g monofilament test and TcpO2
      measurement, dressings, off-loading and systemic therapy according to the IWGDF guidelines .

      Informed consent for participation in the study during the progress of the clinical trial is
      obtained from all subjects.

      Concentration of PB-MNCs autologous cell therapy is produced by a filtration-based
      point-of-care device with the intended for use intra-operatively, from 120 mL of
      anticoagulated blood. All the procedures are performed in operatory room with
      anaesthesiologic support (propofol and/or peripheral block). Blood withdrawal (120 ml) is
      collected through a peripheral venous access, than loaded and gravity filtration is allowed
      in about 10 minutes. During filtration, MNCs are captured in the filter while plasma,
      platelets (PLTs) and red blood cells (RBCs) are not retained. After appropriate surgical
      debridement of the wound bed multiple perilesional and intramuscular injections of PBMNC
      cells suspension (0.2-0.3cc in boluses) are injected along the relevant axis below the knee,
      at intervals of 1-2 cm and to a mean depth of 1.5-2 cm, using a 21G needle. This procedure is
      repeated on each patient for three times, at intervals of 30-45 days from each other.

      Foot-sparing surgery, the removal of all the unviable tissue and the reconstruction of the
      foot to allow a functional deambulation,is performed at the same time of the last implant in
      the patients with increased TcpO2 value above 30 mmHg. Between the implants, diabetologists
      together with nurses evaluated changing in pain, infection signs, wound size, demarcation of
      the necrosis, granulation tissue formation, perilesional tissue trophism and TcpO2 value to
      optimize standard of care. After the first treatment, a two years follow-up is registered,
      with evaluation at 1-3-6-12-18-24 months.

      A baseline assessment is carried out, in order to estimate any differences among cases and
      controls before the treatment. Statistical evaluation includes non-parametric tests
      (Mann-Whitney U test for independent samples for continuous variables and Cochrane chi-square
      test for discrete variables), evaluation of Relative Risk (RR), Absolute Risk Reduction
      (ARR), Relative Risk Reduction (RRR) and Number Needed to Treat (NNT), multivariate survival
      analysis (Kaplan-Meier's survival analysis model).
    

Intervention name(s): Pall Celeris System, point of care device for human cell therapy
Intervention type(s): Device
Intervention description(s): Concentration of PB-MNCs autologous cell therapy was produced by a filtration-based point-of-care device. All the procedures were performed in operatory room with anaesthesiologic support (propofol and/or peripheral block). Blood withdrawal (120 ml) was collected through a peripheral venous access. Blood was loaded, and gravity filtration was allowed to proceed until the upstream side of the filter had no remaining blood; filtration last about 10 minutes. During filtration, MNCs were captured in the filter while plasma, platelets (PLTs) and red blood cells (RBCs) were not retained. Immediately concentrate solution is injected in the perilesional area and intramuscular in the foot and the leg (0.2-0.3cc in boluses) below the knee, at intervals of 1-2 cm and to a mean depth of 1.5-2 cm, using a 21G needle. This procedure is repeated on each patient for three times, at intervals of 30-45 days from each other.
Allocation: Non-Randomized
Intervention model: Sequential Assignment
Intervention model description: We would enroll a cohort of 38 consecutive diabetic patients with CLI in charge at the Diabetic Foot Unit of the San Donato Hospital in Arezzo or referred from other Italian hospitals, who have no option for revascularization or are not further eligible for revascularization according to ESVS ESC 2017 criteria to undergo PB-MNC implantation. Furthermore, an historical control group, with a 1:1 case-control ratio, will be collected backwards from our records, when PBMNCs cellular therapy was not available in our center, with same no-option CLI diagnosis.
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: autologous peripheral blood mononuclear cell, diabetic foot