Randomized trial and local biological effect of autologous platelets used as adjuvant therapy for chronic venous leg ulcers. Synergistic action of protease-modulating matrix and autologous growth factors in healing of diabetic foot ulcers. A prospective randomized trial. Randomised double-blind placebo controlled trial of topical autologous platelet lysate in venous ulcer healing. A prospective, randomized, controlled trial of autologous platelet-rich plasma gel for the treatment of diabetic foot ulcers. Stimulation of repair in chronic, nonhealing, cutaneous ulcers using platelet-derived wound healing formula. A prospective randomized trial of autologous platelet-derived wound healing factors for treatment of chronic nonhealing wounds: a preliminary report.
Platelet products have been proposed as adjuvant therapy for wound healing. We undertook this study to determine the healing effect of topically applied frozen autologous platelets (FAP) on chronic venous ulcers, compared with effect of placebo, and whether use of topical FAP modifies local expression of vascular endothelial growth factor (VEGF), keratinocyte growth factor (KGF), interleukin 8 (IL-8), and tissue inhibitor of metalloproteinase-1 (TIMP-1) in wound fluid.
                This randomized, placebo-controlled, double-blind trial was carried out in institutional practice, with ambulatory patients with proved chronic venous leg ulcers. In all patients, whole venous blood was drawn for preparation of FAP. FAP or normal saline solution was applied three times per week for up to 12 weeks, together with hydrocolloids and standardized compression bandages. Leg ulcer surface was assessed with numerical pictures. IL-8, VEGF, KGF, and TIMP-1 levels were determined (enzyme-linked immunosorbent assay) in wound fluid after each 4 weeks of treatment.
                Fifteen patients were randomized into two groups with comparable leg ulcer characteristics. Mean percent reduction in ulcer area was 26.2% in the FAP group versus 15.2% in the placebo group (P =.94). One ulcer in each group was completely healed at study end. Levels of TIMP-1 increased significantly during FAP treatment. IL-8 concentration was significantly lower in wound fluid of healing ulcers than in the fluid of nonhealing ulcers, in both FAP and placebo groups. Growth factor levels were not modified with FAP treatment.
                Topical autologous platelets have no significant adjuvant effect on healing of chronic venous leg ulcers and increased wound fluid TIMP-1 concentration. Ulcer healing is associated with a decrease in wound fluid IL-8. This study tests the hypothesis that addition of a protease-modulating matrix enhances the efficacy of autologous growth factors in diabetic ulcers. Fifty-one patients with chronic diabetic foot ulcers were managed as outpatients at the Democritus University Hospital of Alexandroupolis and followed up for 8 weeks. All target ulcers were > or = 2.5 cm in any one dimension and had been previously treated only with moist gauze. Patients were randomly allocated in three groups of 17 patients each: Group A was treated only with the oxidized regenerated cellulose/collagen biomaterial (Promogran, Johnson & Johnson, New Brunswick, NJ), Group B was treated only with autologous growth factors delivered by Gravitational Platelet Separation System (GPS, Biomet), and Group C was managed by a combination of both. All ulcers were digitally photographed at initiation of the study and then at change of dressings once weekly. Computerized planimetry (Texas Health Science Center ImageTool, Version 3.0) was used to assess ulcer dimensions that were analyzed for homogeneity and significance using the Statistical Package for Social Sciences, Version 13.0. Post hoc analysis revealed that there was significantly greater reduction of all three dimensions of the ulcers in Group C compared to Groups A and B (all P<.001). Although reduction of ulcer dimensions was greater in Group A than in Group B, these differences did not reach statistical significance. It is concluded that protease-modulating dressings act synergistically with autologous growth factors and enhance their efficacy in diabetic foot ulcers. to assess the effect of topical autologous platelet lysate on the healing of chronic venous ulcers. Design: a randomised placebo controlled double-blind trial.
                all patients had blood taken for preparation of autologous platelet lysate. Methods: patients with proven chronic venous ulceration were randomised to the trial. Autologous platelet lysate or placebo buffer solution were applied twice per week for up to 9 months in combination with standardised compression bandaging.
                a total of 86 patients (36 males and 50 females, median age 70 years) were entered into the study. The patient and treatment groups were equivalent for ulcer size, ulcer duration and other characteristics. Cox regression analysis of the time to ulcer healing did not show any difference in healing between platelet lysate and placebo application.
                platelet lysate prepared and delivered by the method used in this study had no influence on the healing of chronic venous ulceration.
                Copyright 2000 Harcourt Publishers Ltd. Nonhealing diabetic foot ulcers are a common cause of amputation. Emerging cellular therapies such as platelet-rich plasma gel provide ulcer management options to avoid loss of limb. The purpose of this prospective, randomized, controlled, blinded, multicenter clinical study was to evaluate the safety and efficacy of autologous platelet-rich plasma gel for the treatment of nonhealing diabetic foot ulcers. One hundred, twenty-nine (129) patients were screened; 72 completed a 7-day screening period and met the study inclusion criteria. Patients were randomized into two groups - the standard care with platelet-rich plasma gel or control (saline gel) dressing group - and evaluated biweekly for 12 weeks or until healing. Healing was confirmed 1 week following closure and monitored for another 11 weeks. An independent audit led to the exclusion of 32 patients from the final per-protocol analysis because of protocol violations and failure to complete treatment. In this group, 13 out of 19 (68.4%) of the platelet-rich plasma gel and nine out of 21 (42.9%) of the control wounds healed. After adjusting for wound size outliers (n = 5), significantly more platelet-rich plasma gel (13 out of 16, 81.3%) than control gel (eight out of 19, 42.1%) treated wounds healed (P = 0.036, Fisher's exact test). Kaplan-Meier time-to-healing also was significantly different between groups (log-rank, P = 0.0177). No treatment-related serious adverse events were reported and bovine thrombin used in the preparation of PRP did not cause Factor V inhibition. When used with good standards of care, the majority of nonhealing diabetic foot ulcers treated with autologous platelet-rich plasma gel can be expected to heal. Chronic, nonhealing, cutaneous ulcers are a serious clinical problem. The results of previous studies using platelet-derived wound healing formula (PDWHF), derived from autologous platelets, provided evidence that PDWHF actively stimulates repair of the wound. To test whether or not PDWHF accelerates repair, a prospectively randomized, blinded trial was conducted using a placebo control. A total of 32 patients with chronic, nonhealing, cutaneous wounds of the lower extremity were randomized and treated for eight weeks with PDWHF or placebo. Epithelialization of the wound was the end point of study. In the group who received treatment, 81 per cent of patients had epithelialization in eight weeks compared with 15 per cent in the control group (p less than 0.0001). After crossover to treatment with PDWHF, all of the patients in the control group had epithelialization in an average of 7.1 weeks. Regression analysis of the rates of epithelialization also showed significant differences during the initial eight week trial and showed no difference after crossover of the control group to therapy with PDWHF. Results from this study demonstrate a highly statistically significant effect of topically applied platelet-derived growth factors on the repair of chronic, nonhealing, cutaneous ulcers. Previous studies have suggested that topically applied platelet-derived wound healing factors (PDWHF) accelerate wound healing by stimulating angiogenesis, fibroblast proliferation, and collagen synthesis. To assess the ability of platelet factors to facilitate healing of chronic cutaneous ulcers we performed a randomized, prospective, double-blind, placebo-controlled study of topical PDWHF in 18 patients with 26 lower extremity wounds refractory to conventional therapy. Wounds were present for at least 8 weeks (mean, 5.5 +/- 4.3 months). They were extensively debrided initially and were measured and photographed at weekly intervals for 12 weeks. Eight patients with nine wounds were treated with placebo solution (controls), and 10 patients with 17 wounds were treated with PDWHF (treatment group). Seventy-eight percent of patients had diabetes mellitus, 72% had occlusive peripheral vascular disease, and 28% had venous disease; distribution of these disorders was equivalent in both groups. Ankle-brachial indexes, which were often spuriously elevated, averaged 0.93 +/- 0.54 in controls and 1.04 +/- 0.56 in patients treated with PDWHF (p greater than 0.5). Mean transcutaneous oxygen tension was 37.8 +/- 11.9 mmHg in controls and 37.1 +/- 9.1 mmHg in patients treated with PDWHF. Initial wound area was larger in controls than in the patients treated with PDWHF (28.9 +/- 45.2 cm2 vs 13.0 +/- 4.4 cm2), but this difference was not statistically significant (p = 0.19). Three (33%) wounds (in two patients) healed in controls, and four (24%) wounds (in three patients) healed in the PDWHF group (p greater than 0.5). The rate of healing in controls was 1.9 +/- 2.7 cm2/week.(ABSTRACT TRUNCATED AT 250 WORDS)
There is currently no evidence to suggest that autologous PRP is of value for treating chronic wounds. However, current evidence is based on a small number of RCTs, most of which are either at high or unclear risk of bias. Well-designed and adequately powered clinical trials are needed.