Short-Term Safety and Performance of Two Wound Dressings Evaluation (POLTX_Fiber)

Experimental: POLTX_Fiber arm

POLTX_Fiber, an absorbent gelling fiber dressing for moderate-high exudate chronic wounds

Kombinationsprodukt: Politix Fiber arm

POLTX_Fiber, an absorbent gelling fiber dressing for moderate-high exudate chronic wounds, applied strictly per IFU and local protocol.

Application workflow (per visit). It will proceed as follows:

• Removal of old dressing.
• Application of analgesic if necessary (timed to peak during debridement/dressing).
• Debridement if necessary (sharp/hydrolytic per local practice; document method/date).
• Wound cleansing (sterile 0.9% saline or Ringer's; no antiseptics) (IWII 2025).
• Application of a suitable secondary dressing according to wound phase and medical prescription to secure the primary and maintain moisture balance.
• Compression therapy for venous disease according to the standardized procedure described in Section 6.1; apply off-loading for DFU per local SOP where indicated.
• Documentation in the eCRF (Imito Wound® digital photographs/planimetry, tissue composition, exudate character, TILI infection score, VAS pain, any device deficiencies).

Kein Eingriff: Suprasorb® Liquacel Pro, CE-marked gelling fiber dressing

Suprasorb® Liquacel Pro arm

Photographic evaluation

Standardized photographs will be obtained using ImitoWound® after dressing removal, wound debridement (if applicable) and wound cleansing at a frequency of no more than once per week, even if multiple dressing changes take place during the same week. ImitoWound® will be used in an iPad as instructed in supplier's wound imaging and measurement guidelines. The camera of the iPad will be maintained 20 to 30 cm away from and parallel to the wound. A calibration marker (quick response [QR] code) will be positioned next to and in the same plane of the wound, and a photograph will be taken after recognition of the QR code by ImitoWound®, providing automatic wound measurements. This marker will allow standardised image captures maintaining fixed distance, lighting, and calibration.

Study nurses will receive concise training and a working instruction with step-by-step procedure on how to use ImitoWound®. Images will be anonymized and centrally reviewed by two blinded assessors; discrepancies >

Change in wound area

Wound area (length, width, depth, area) will be recorded using ImitoWound®. Percent wound area reduction (PWAR) from baseline to EoT (Day 30) or follow-up (Week 8 and Week 12) will be computed automatically using the following formula:

PWAR = [(Wound area at baseline - Wound area at follow-up) / Wound area at baseline] × 100.

Higher percentages indicate faster healing. Where digital imaging is unavailable, manual planimetry measurements may be used and documented.

Wound healing progression

Wound healing progression over 12 weeks will be measured from pictures of the wound taken with ImitoWound

Change in wound tissue composition

Change from baseline in wound tissue composition, as assessed using digital wound assessment technology. Tissue composition (e.g. granulation, slough, necrosis) will be determined automatically through ImitoWound® image analysis at baseline and when wound images are captured during wound care. Results will be expressed as a percentage of total wound area (sum = 100%), enabling consistent quantification of healing dynamics over time.

Local Infection Assessment

Local infection will be evaluated at each visit using the Therapeutic Index for Local Infection (TILI), a validated clinical tool for early infection detection (erythema, peri-wound oedema, malodour, exudate change, pain).

A TILI score ≥ 5 indicates clinically relevant infection requiring medical evaluation or treatment adjustment.

Global Tolerability Assessment

Usability of POLTX_Fiber will be assessed using a short Investigator Usability and Handling Questionnaire based on ISO 14155:2020 and FDA Human Factors guidance (2016). Parameters include ease of application/removal, dressing integrity, handling characteristics, and overall satisfaction. Rated on a 5-point Likert scale (Total score ranges from 5 to 22).

Pain (Visual Analogue Scale (VAS)

Pain will be recorded at each dressing change using a 10-cm VAS (0 = no pain, 10 = worst pain imaginable). Pain on application, during wear, and on removal will be documented.

Exudate management

Assessment of characteristics of wound exudate In addition to color and odor of wound exudate will be recorded using simplified Keast (2022) descriptors:

• Color: serous (clear/amber), serosanguinous (pink), purulent (opaque/yellow/green).
• Odor: absent, faint, moderate, strong. Abrupt increases in volume or the emergence of purulent/strongly malodorous exudate will trigger reassessment of the TILI Score and clinical review to rule out infection.

Frequency of dressing changes

The total number of dressing changes (scheduled and unscheduled) during the thirty-day treatment will be recorded in the eCRF. Each entry will include:

• Date and time of change
• Reason (e.g., exudate saturation, leakage, odor, clinical judgement)
• Dressing type (POLTX_Fiber vs SoC)
• Cumulative dressing count Participants will be categorized as ≤2 changes/week, 3-4 changes/week, or ≥5 changes/week. Lower dressing-change frequency indicates better absorbency and longer wear time.

Global Tolerability Assessment by participants

Patients will independently assess tolerability on a 3-point scale (Chandanwale 2014): 0 = No issues, 1 = Moderate, 2 = Poor.

Sociodemographic and diagnostic data

At Screening, investigators will collect the following information and record it in the electronic Case Report Form (eCRF):

• Sociodemographic data (age, sex, occupation, level of mobility, living situation).
• Relevant comorbidities (e.g., diabetes, peripheral vascular disease, venous insufficiency).
• Current medications or topical wound treatments.
• Lifestyle factors (smoking and alcohol use).

Wound etiology

At Baseline, wound etiology (e.g., venous leg ulcer, diabetic foot ulcer, pressure ulcer) will be documented

Wound anatonical location

Wound anatomical location will be documented at baseline

Wound diagnostic classification

Wound diagnostic classification (if applicable, e.g., Wagner grade for diabetic ulcers or EPUAP stage for pressure ulcers).