This single-arm, open-label, multicenter clinical study was conducted in 3 Maccabi Health Care Wound Clinics (Tel Aviv) as well as at Assaf Harofeh Medical Center (Be’er Ya’akov) and at Meir Medical Center (Kfar Saba), all located in Israel.
Ethical approval
The study protocol was approved by the Israeli Ministry of Health (Jerusalem, Israel) and the Ethics Committee/Institutional Review Boards of Asuta Medical Cener (Tel Aviv, Israel), Maccabi Health Care Services (Tel Aviv, Israel), Assaf Harofeh Medical Center, and Meir Hospital. All patients provided written, informed consent before initiating participation.
Inclusion criteria
Patients 18 years of age or older with a chronic neuropathic (University of Texas Wound Classification 1A), venous, posttraumatic, or postoperative lower limb wound measuring 1 cm2 to 20 cm² that scored ≥ E on the granulometer scale were eligible to participate in the study.
Exclusion criteria
Patients with an acute ulcer (≤ 4 weeks), multiple ulcers (≥ 2), clinical evidence of infection by physical examination, hemoglobin A1C > 12, ankle-brachial index < 0.45, an immunosuppressed state, active malignant disease, end-stage renal failure, liver dysfunction, positive pregnancy test at enrollment, known hypersensitivity and/or allergy to collagen, or participating in any other clinical trials were excluded from the study.
rhCollagen flowable gel dressing
The rhCollagen flowable gel dressing is an advanced wound care device primarily comprised of lyophilized tobacco plant-purified type I recombinant human collagen and hydroxy propyl methyl cellulose for the management of acute and chronic wounds. Recombinant human type I collagen is supplied as a powder in a syringe that is hydrated with saline just before application to form a gel.
Treatment protocol
All wounds were photographed prior to treatment with rhCollagen. Blood chemistry and complete blood count (CBC) were performed at baseline.
A preliminary surgical wound debridement was performed until viable wound bed tissue was reached. Recombinant human type I collagen was applied once to the wound bed by using one or two 2-cc doses of the gel to cover the whole wound area, followed by placement of a secondary dressing (sterile gauze pad [Nissan Medical Industries, Ltd., Israel]) (Figure 2). Patients returned to the clinic weekly ± 2 days thereafter for wound debridement; wound size, granulation, and epithelialization assessments; and application of polyurethane dressing.
In addition, wound margins were assessed using the Draize scale15 and neuropathic ulcers were classified using the University of Texas Wound Classification System.16 Patients rated pain in the wounded area using a standard point (1–10) visual analogue scale (VAS). Wounds were photographed at each visit (Canon pocket camera; Tokyo, Japan). All reports of adverse events, infection, and change in concomitant medications were recorded throughout the study. Blood chemistry and CBC were drawn again at the last visit.
Data and statistical analysis
Data were analyzed using the SAS version 9.3 software (SAS Institute, Cary, NC). Paired t test or signed rank test for 2 means for paired observations were applied, as appropriate, to test the statistical significance of changes in wound size and percent of granulation and epithelialization at follow-up visits as compared with baseline. A 95% confidence interval was calculated for the proportion of patients with signs of infection. All tests were 2-tailed, and P < .05 was considered statistically significant.