Silica Gel Fiber Wound Dressing for Chronic Venous Leg Ulcers

• Incidence of complete wound healing of target ulcer at 4, 8 and 12 weeks, defined as full epithelialisation of the wound with the absence of drainage [ Time Frame: Week 4/8/12 ] [ Designated as safety issue: No ]
• Rate of recurrence of wound at end of follow-up period of 3 months [ Time Frame: Week 24 ] [ Designated as safety issue: No ]
• Size (cm2, measured by Visitrak Wound Measurement System) of target ulcer (Absolute size measured once per week and change between assessments at weeks 0, 4, 8, and 12) [ Time Frame: Week 12/24 ] [ Designated as safety issue: No ]

Silica Gel Fiber is a bioresorbable, inorganic silica gel fibre patch promoting skin tissue growth and enhanced wound healing for all types of chronic wounds. It is applied as patch and will be hold in place by a secondary dressing for maintaining the moist wound environment. The study is aimed to demonstrate superiority over a standard wound treatment for chronic venous leg ulcers. The primary efficacy variable is time to healing.

• Device: Silica Gel Fiber
  Silica Gel Fiber (SGF) applications as required
• Device: Standard-of-Care
  Standard-of-Care with dressing changes twice per week using Mepitel and Mepilex wound dressings

• Experimental: Arm 1
  Intervention: Device: Silica Gel Fiber
• Arm 2
  Intervention: Device: Standard-of-Care

Inclusion Criteria:

• At least one chronic venous leg ulcer fulfilling all of the following criteria:

  • Size: >/= 5 cm2 and </= 40 cm2 (measured by Visitrak Wound Measurement System)
  • Duration: >/= 3 month < 5 years
  • Location: Between and including knee and ankle
  • Depth: Involving dermis, with no exposed muscle, tendon or bone. Characterized by a viable wound bed with granulation tissue
  • The etiology of the ulcer as "venous" is proven by Duplex or Doppler sonography and with ankle/brachial arterial Doppler pressure index > 0.8 (exclusion criterion for peripheral arterial disease) and < 1.3 (exclusion criterion for medial sclerosis), or with a laser Doppler value > 40
• Treatment with active wound care agents paused for 14 days before start of study treatment

Exclusion Criteria:

• Only ulcers of other than venous etiology, e.g., diabetic ulcers or ulcers resulting from electrical, chemical, or radiation insult, after contact eczema, etc.
• History of radiotherapy to the target ulcer site
• Signs of infection as defined by rubor, dolor, calor, tumor, functio laesa. Fever (38°C sublingual, rectal, or ear), rigors, or leukocytosis will be considered as signs of infection in the context of the general appearance of the wound
• Target ulcer lacking any sign of granulation tissue (bradytrophic wound bed)
• Presence of necrotic tissue
• Presence of fistula
• History of connective tissue disease, e.g., systemic lupus erythematodes, systemic sclerosis, Sjögren's syndrome or mixed connective tissue disease
• Uncontrolled congestive heart failure
• Malnutrition (albumin < 2.5 g/dl; to be measured if clinical signs of malnutrition are being observed)
• Uncontrolled diabetes (HbA1c > 8 %)
• Previous organ transplantation
• Active malignant disease
• Severe rheumatoid arthritis
• Undergoing haemodialysis
• Active sickle cell disease
• Patients who are immunocompromised for reasons such as therapy with corticosteroids, chemotherapy, antiangiogenic or immunosuppressive agents, or due to immunodeficiency syndromes
• Pregnant or nursing women
• Woman of childbearing potential who are not practicing acceptable methods of birth control during the investigation period
• Known allergy to any of the devices' constituents