Which is the better option: recombinant human PDGF-BB 0.01% gel or standard wound care, in diabetic neuropathic large plantar ulcers off-loaded by a customized contact cast?

Effectiveness of interventions to enhance healing of chronic foot ulcers in diabetes: A systematic review

BACKGROUND

It is critical that interventions used to enhance the healing of chronic foot ulcers in diabetes are backed by high-quality evidence and cost-effectiveness. In previous years, the systematic review accompanying guidelines published by the International Working Group of the Diabetic Foot performed 4-yearly updates of previous searches, including trials of prospective, cross-sectional and case-control design.

AIMS

Due to a need to re-evaluate older studies against newer standards of reporting and assessment of risk of bias, we performed a whole new search from conception, but limiting studies to randomised control trials only.

MATERIALS AND METHODS

For this systematic review, we searched PubMed, Scopus and Web of Science databases for published studies on randomised control trials of interventions to enhance healing of diabetes-related foot ulcers. We only included trials comparing interventions to standard of care. Two independent reviewers selected articles for inclusion and assessed relevant outcomes as well as methodological quality.

RESULTS

The literature search identified 22,250 articles, of which 262 were selected for full text review across 10 categories of interventions. Overall, the certainty of evidence for a majority of wound healing interventions was low or very low, with moderate evidence existing for two interventions (sucrose-octasulfate and leucocyte, platelet and fibrin patch) and low quality evidence for a further four (hyperbaric oxygen, topical oxygen, placental derived products and negative pressure wound therapy). The majority of interventions had insufficient evidence.

CONCLUSION

Overall, the evidence to support any other intervention to enhance wound healing is lacking and further high-quality randomised control trials are encouraged.

Guidelines on interventions to enhance healing of foot ulcers in people with diabetes (IWGDF 2023 update)

AIMS

Principles of wound management, including debridement, wound bed preparation, and newer technologies involving alternation of wound physiology to facilitate healing, are of utmost importance when attempting to heal a chronic diabetes-related foot ulcer. However, the rising incidence and costs of diabetes-related foot ulcer management necessitate that interventions to enhance wound healing of chronic diabetes-related foot ulcers are supported by high-quality evidence of efficacy and cost effectiveness when used in conjunction with established aspects of gold-standard multidisciplinary care. This is the 2023 International Working Group on the Diabetic Foot (IWGDF) evidence-based guideline on wound healing interventions to promote healing of foot ulcers in persons with diabetes. It serves as an update of the 2019 IWGDF guideline.

MATERIALS AND METHODS

We followed the GRADE approach by devising clinical questions and important outcomes in the Patient-Intervention-Control-Outcome (PICO) format, undertaking a systematic review, developing summary of judgements tables, and writing recommendations and rationale for each question. Each recommendation is based on the evidence found in the systematic review and, using the GRADE summary of judgement items, including desirable and undesirable effects, certainty of evidence, patient values, resources required, cost effectiveness, equity, feasibility, and acceptability, we formulated recommendations that were agreed by the authors and reviewed by independent experts and stakeholders.

RESULTS

From the results of the systematic review and evidence-to-decision making process, we were able to make 29 separate recommendations. We made a number of conditional supportive recommendations for the use of interventions to improve healing of foot ulcers in people with diabetes. These include the use of sucrose octasulfate dressings, the use of negative pressure wound therapies for post-operative wounds, the use of placental-derived products, the use of the autologous leucocyte/platelet/fibrin patch, the use of topical oxygen therapy, and the use of hyperbaric oxygen. Although in all cases it was stressed that these should be used where best standard of care was not able to heal the wound alone and where resources were available for the interventions.

CONCLUSIONS

These wound healing recommendations should support improved outcomes for people with diabetes and ulcers of the foot, and we hope that widescale implementation will follow. However, although the certainty of much of the evidence on which to base the recommendations is improving, it remains poor overall. We encourage not more, but better quality trials including those with a health economic analysis, into this area.

Comparative efficacy of growth factor therapy in healing diabetes-related foot ulcers: A network meta-analysis of randomized controlled trials

INTRODUCTION

This study examined the relative efficacy of growth factor therapies in healing diabetes-related foot ulcers (DFU).

METHODS

PubMed and Cochrane databases were searched for randomized controlled trials testing growth factor therapies for treating DFU. The primary outcome was complete wound closure. Results were reported as relative risk (RR) ± 95% credible intervals (CrI). The risk of bias was assessed using Cochrane's RoB-2 tool.

RESULTS

A total of 31 RCTs involving 2174 participants were included. Only 13 of the trials (n = 924) reported on the aetiology of the ulcers (85.4% neuropathic and 14.6% ischaemic). Epidermal growth factor (RR 3.83; 95% CrI 1.81, 9.10), plasma-rich protein (PRP) (RR 3.36; 95% CrI 1.66, 8.03) and platelet-derived growth factor (PDGF) (RR 2.47; 95% CrI 1.23, 5.17) significantly improved the likelihood of complete ulcer healing compared to control. Sub-analyses suggested that PRP (3 trials - RR 9.69; 95% CrI 1.37, 103.37) and PDGF (6 trials - RR 2.22; 95% CrI 1.12, 5.19) significantly improved the likelihood of wound closure amongst trial mainly recruiting participants with neuropathic ulcers. Eleven trials had a low risk of bias, 9 had some concerns and 11 had a high risk of bias. Sub-analysis of trials with a low risk of bias suggested that none of the growth factors significantly improved ulcer healing compared with control.

DISCUSSION

This network meta-analysis found low-quality evidence that Epidermal growth factor, PRP and PDGF therapy improved DFU healing likelihood compared with control. Larger well-designed trials are needed.

HATMSC Secreted Factors in the Hydrogel as a Potential Treatment for Chronic Wounds-In Vitro Study

Mesenchymal stem cells (MSCs) can improve chronic wound healing; however, recent studies suggest that the therapeutic effect of MSCs is mediated mainly through the growth factors and cytokines secreted by these cells, referred to as the MSC secretome. To overcome difficulties related to the translation of cell therapy into clinical use such as efficacy, safety and cost, we propose a hydrogel loaded with a secretome from the recently established human adipose tissue mesenchymal stem cell line (HATMSC2) as a potential treatment for chronic wounds. Biocompatibility and biological activity of hydrogel-released HATMSC2 supernatant were investigated in vitro by assessing the proliferation and metabolic activity of human fibroblast, endothelial cells and keratinocytes. Hydrogel degradation was measured using hydroxyproline assay while protein released from the hydrogel was assessed by interleukin-8 (IL-8) and macrophage chemoattractant protein-1 (MCP-1) ELISAs. Pro-angiogenic activity of the developed treatment was assessed by tube formation assay while the presence of pro-angiogenic miRNAs in the HATMSC2 supernatant was investigated using real-time RT-PCR. The results demonstrated that the therapeutic effect of the HATMSC2-produced factors is maintained following incorporation into collagen hydrogel as confirmed by increased proliferation of skin-origin cells and improved angiogenic properties of endothelial cells. In addition, HATMSC2 supernatant revealed antimicrobial activity, and which therefore, in combination with the hydrogel has a potential to be used as advanced wound-healing dressing.

Topical Erythropoietin Accelerates Wound Closure in Patients with Diabetic Foot Ulcers: A Prospective, Multicenter, Single-Blind, Randomized, Controlled Trial

The diabetic foot ulcer (DFU) is a major disabling complication of diabetes mellitus. Growing evidence suggests that topical erythropoietin (EPO) can promote wound healing. The aim of this study is to clinically assess the efficacy of a proprietary topical EPO-containing hydrogel for treating DFUs. We conducted a randomized, controlled trial in 20 patients with DFUs. After a 14-day screening period, the DFUs of 20 eligible participants who fulfilled the inclusion criteria were randomly assigned (1:1) to either a 12-week of daily treatment with topical EPO and standard-of-care (SOC) or SOC treatment alone. The DFUs were assessed weekly until week 12. The primary outcome was 75% ulcer closure or higher. After 12 weeks of treatment, 75% ulcer closure was achieved in 6 of the 10 patients whose DFUs were treated with topical EPO and in one of the 8 patients whose DFUs were treated with SOC alone. The mean area of the DFUs that were treated with topical EPO and SOC was significantly smaller than those treated with SOC alone (1.2 ± 1.4 cm² vs. 4.2 ± 3.4 cm²; p = 0.023). Re-epithelialization was faster in the topically EPO-treated DFUs than in the SOC-treated DFUs. There were no treatment-related adverse events. We conclude that topical EPO is a promising treatment for promoting the healing of DFUs. Clinical Trial Registration number: NCT02361931.

The Role of Recombinant Proteins and Growth Factors in the Management of Diabetic Foot Ulcers: A Systematic Review of Randomized Controlled Trials

BACKGROUND

Recombinant proteins and growth factors are emerging therapies for diabetic foot ulcers. Despite several clinical reports, there has been no comprehensive and systematic assessment of the totality of clinical evidence on the efficacy and safety of recombinant proteins and growth factors in diabetic foot ulcers. We tried to address this gap through an updated systematic review of randomized controlled trials (RCTs).

METHODS

PubMed, the Cochrane Library, Scopus, Embase, and Google Scholar databases were searched, and RCTs on the efficacy of recombinant proteins and growth factors in the treatment of cutaneous wounds in diabetic patients were selected. The literature search and assessment were performed by two independent reviewers. Methodological quality of studies was appraised using the Jadad scale.

RESULTS

We identified 26 RCTs involving diabetic patients with ulcer that evaluated the effectiveness of platelet-derived growth factor, epidermal growth factor, fibroblast growth factor, granulocyte colony-stimulating factor, vascular endothelial growth factor, erythropoietin, transforming growth factor, talactoferrin, and rusalatide acetate. The main primary outcome was complete healing though different indices were employed to define this such as wound closure, granulation tissue formation, or complete reepithelialization. Few studies had a follow-up period to report any recurrence and amputation rate. No adverse effect was reported due to the intervention.

CONCLUSION

Overall, there is a greater agreement on the effectiveness of EGF to enhance the healing of diabetic ulcers. Nevertheless, extant evidence is lacking for other agents since few trials have been conducted for most of the growth factors and available studies are heterogeneous in their methodologies.

Role of Topical Biological Therapies and Dressings in Healing Ischemic Wounds

Ischemic wounds are the most severe expression of critical limb ischemia (CLI), and they have been defined clinically as an end stage of peripheral arterial disease. Urgent revascularization is a fundamental part for limb salvage in patients with CLI. However, the risk of revascularization should be weighed against the likelihood of success given a patient’s life-threatening comorbidities. Once the condition of arterial insufficiency is revascularized, wound care is an important aspect to promote the wound healing process and infection control. MOIST concept for wound care is a modern systematic treatment for enhanced wound healing process. Currently, advanced biological therapies are emerging in ischemic wound therapies to restore the wound healing process and involve active biological agents to support the wound healing process. We studied and summarized the different types of available topical biological therapies and their mechanisms on the healing process including platelet-derived growth factor, epidermal growth factor, fibroblast growth factor, and vascular endothelial growth factor, platelet-rich plasma, and honey for local wound care of patient with CLI. Our review suggests that topical platelet-derived growth factor, epidermal growth factor, platelet-rich plasma, and honey are available as well as considered in the ischemic wound healing process enhancement through the MOIST concept. In conclusion, biologic wound dressing or topical agent therapy may improve the wound healing process, increase limb salvage, is inexpensive, and provides potential safety with nontoxic low-risk therapy in patients with an ischemic wound. Thus, local wound care by biological dressing should be added in adjuvant treatment for ischemic wound patients. However, further randomized studies are needed to support efficacy and long-term outcomes of these biological dressing in patients with ischemic wound.

Transition of serum cytokines following pancreaticoduodenectomy: A subsidiary study of JAPAN-PD

Our previous study aimed to examine the effect of TJ-100, a widely used herbal medicine, on intestinal function following pancreaticoduodenectomy (PD) in a multicenter, randomized, double-blinded, placebo-controlled manner (JAPAN-PD study). This concomitant study investigated the effect of TJ-100 on serum cytokine levels in patients who underwent PD. Due to the fact that several clinical variables can affect the absolute values of baseline serum cytokine levels, the ratios of the cytokine levels on postoperative day (POD)3 to those on POD1 were also used for analysis. The present study enrolled 180/224 randomized patients, of whom 91 received TJ-100 and 89 received placebo. As the main findings of the analysis, Wilcoxon signed-rank test revealed no significant difference in the levels of serum cytokines between the groups; however, patients in the TJ-100 group without severe inflammatory complications exhibited significantly higher ratios of interleukin (IL)-4 (n=123), IL-9 (n=72), IL-10 (n=97), PDGF-BB (n=143) and tumor necrosis factor-α (n=135), compared with patients in the Placebo Group (P<0.05). According to the results of the present study, TJ-100 has an effect on the change in serum cytokine levels from POD1 to POD3 following PD. However, the role of different transition pattern of cytokines in postoperative recovery following PD has to be investigated by further mechanical studies focusing on these extracted cytokines (ClinicalTrials.gov; no. NCT01607307; May 30, 2012).

Regulatory Mechanisms of the Wnt/β-Catenin Pathway in Diabetic Cutaneous Ulcers

Skin ulcers are a serious complication of diabetes. Diabetic patients suffer from vascular lesions and complications such as peripheral neuritis, peripheral vascular lesions, and collagen abnormalities, which result in skin wounds that are refractory and often develop into chronic ulcers. The healing of skin ulcers requires an inflammatory reaction, wound proliferation, remodeling regulation, and control of stem cells. Studies investigating diabetic cutaneous ulcers have focused on cellular and molecular levels. Diabetes can cause nerve and blood vessel damage, and persistent high blood sugar levels can cause systemic multisite nerve damage based on peripheral neuropathy. The long-term hyperglycemia state enables the polyol glucose metabolism pathway to be activated, increasing the accumulation of toxic substances in the vascular injured nerve tissue cells. Sustained hyperglycemia leads to dysfunction of epithelial cells, leading to a decrease in pro-angiogenic signaling and nitric oxide production. In addition, due to impaired leukocyte function in hyperglycemia, immune function is impaired and the immune response at relevant sites is insufficient, making diabetic foot more difficult to heal. The Wnt/β-catenin pathway is a highly conserved signal transduction pathway involved in a variety of biological processes, such as cell proliferation, apoptosis, and differentiation. It is considered an important pathway involved in the healing of skin wounds. This article summarizes the mechanism of action of the Wnt/β-catenin pathway involved in the inflammatory responses to diabetic ulcers, wound proliferation, wound remodeling, and stem cells. The interactions between the Wnt signal pathway and other metabolic pathways are also discussed.

Growth factors for diabetic foot ulcers: mixed treatment comparison analysis of randomized clinical trials

AIMS

Topical growth factors accelerate wound healing in patients with diabetic foot ulcers (DFU). Due to the absence of head-to-head comparisons, we carried out Bayesian network meta-analysis to compare the efficacy and safety of growth factors.

METHODS

Using an appropriate search strategy, randomized controlled trials on topical growth factors compared with standard of care in patients with DFU, were included. Proportion of patients with complete healing was the primary outcome. Odds ratio (95% confidence interval) was used as the effect estimate and random effects model was used for both direct and indirect comparisons. Markov Chain Monte Carlo simulation was used to obtain pooled estimates. Rankogram was generated based on surface under the cumulative ranking curve (SUCRA).

RESULTS

A total of 26 studies with 2088 participants and 1018 events were included. The pooled estimates for recombinant epidermal growth factor (rhEGF), autologous platelet rich plasma (PRP), recombinant human platelet-derived growth factor (rhPDGF) were 5.72 [3.34, 10.37], 2.65 [1.60, 4.54] and 1.97 [1.54, 2.55] respectively. SUCRA for rhEGF was 0.95. Sensitivity analyses did not reveal significant changes from the pooled estimates and rankogram. No differences were observed in the overall risk of adverse events between the growth factors. However, the growth factors were observed to lower the risk of lower limb amputation compared to standard of care.

CONCLUSION

To conclude, rhEGF, rhPDGF and autologous PRP significantly improved the healing rate when used as adjuvants to standard of care, of which rhEGF may perform better than other growth factors. The strength of most of the outcomes assessed was low and the findings may not be applicable for DFU with infection or osteomyelitis. The findings of this study needs to be considered with caution as the results might change with findings from head-to-head studies.

Syndesome Therapeutics for Enhancing Diabetic Wound Healing

Chronic wounds represent a major healthcare and economic problem worldwide. Advanced wound dressings that incorporate bioactive compounds have great potential for improving outcomes in patients with chronic wounds but significant challenges in designing treatments that are effective in long-standing, nonhealing wounds. Here, an optimized wound healing gel was developed that delivers syndecan-4 proteoliposomes ("syndesomes") with fibroblast growth factor-2 (FGF-2) to enhance diabetic wound healing. In vitro studies demonstrate that syndesomes markedly increase migration of keratinocytes and fibroblasts isolated from both nondiabetic and diabetic donors. In addition, syndesome treatment leads to increased endocytic processing of FGF-2 that includes enhanced recycling of FGF-2 to the cell surface after uptake. The optimized syndesome formulation was incorporated into an alginate wound dressing and tested in a splinted wound model in diabetic, ob/ob mice. It was found that wounds treated with syndesomes and FGF-2 have markedly enhanced wound closure in comparison to wounds treated with only FGF-2. Moreover, syndesomes have an immunomodulatory effect on wound macrophages, leading to a shift toward the M2 macrophage phenotype and alterations in the wound cytokine profile. Together, these studies show that delivery of exogenous syndecan-4 is an effective method for enhancing wound healing in the long-term diabetic diseased state.

Cost-Effectiveness of Becaplermin Gel on Diabetic Foot Ulcer HealingChanges in Wound Surface Area

BACKGROUND

A comparison of the cost-effectiveness of becaplermin plus good wound care (BGWC) versus good wound care (GWC) alone in treating patients with diabetic foot ulcers (DFUs) may enable physicians and health-care decision makers in the United States to make better-informed choices about treating DFUs, which currently contribute to a substantial portion of the economic burden of diabetes.

METHODS

Data from three phase III trials were used to predict expected 1-year costs and outcomes, including the average percentage reduction from baseline in wound surface area (WSA), the direct costs of DFU therapy, and the cost per cm(2) of WSA reduction.

RESULTS

At 20 weeks, the BGWC group had a statistically greater probability of complete wound closure than the GWC group (50% versus 35%; P = .015). Based on reported WSA reduction rates, DFUs in the BGWC group were predicted to close by 100% at 27 weeks, and those in the GWC group were predicted to close by 88% at 52 weeks. The GWC group had higher total estimated 1-year direct cost of DFU care ($6,809 versus $4,414) and higher cost per cm(2) of wound closure ($3,501 versus $2,006).

CONCLUSIONS

Becaplermin plus good wound care demonstrated economic dominance compared with GWC by providing better clinical outcomes via faster reduction in WSA and higher rates of closure at a lower direct cost.

Growth factors for treating diabetic foot ulcers

BACKGROUND

Foot ulcers are a major complication of diabetes mellitus, often leading to amputation. Growth factors derived from blood platelets, endothelium, or macrophages could potentially be an important treatment for these wounds but they may also confer risks.

OBJECTIVES

To assess the benefits and harms of growth factors for foot ulcers in patients with type 1 or type 2 diabetes mellitus.

SEARCH METHODS

In March 2015 we searched the Cochrane Wounds Group Specialised Register, The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), Ovid MEDLINE, Ovid MEDLINE (In-Process & Other Non-Indexed Citations, Ovid EMBASE and EBSCO CINAHL. There were no restrictions with respect to language, date of publication or study setting.

SELECTION CRITERIA

Randomised clinical trials in any setting, recruiting people with type 1 or type 2 diabetes mellitus diagnosed with a foot ulcer. Trials were eligible for inclusion if they compared a growth factor plus standard care (e.g., antibiotic therapy, debridement, wound dressings) versus placebo or no growth factor plus standard care, or compared different growth factors against each other. We considered lower limb amputation (minimum of one toe), complete healing of the foot ulcer, and time to complete healing of the diabetic foot ulcer as the primary outcomes.

DATA COLLECTION AND ANALYSIS

Independently, we selected randomised clinical trials, assessed risk of bias, and extracted data in duplicate. We estimated risk ratios (RR) for dichotomous outcomes. We measured statistical heterogeneity using the I(2) statistic. We subjected our analyses to both fixed-effect and random-effects model analyses.

MAIN RESULTS

We identified 28 randomised clinical trials involving 2365 participants. The cause of foot ulcer (neurologic, vascular, or combined) was poorly defined in all trials. The trials were conducted in ten countries. The trials assessed 11 growth factors in 30 comparisons: platelet-derived wound healing formula, autologous growth factor, allogeneic platelet-derived growth factor, transforming growth factor β2, arginine-glycine-aspartic acid peptide matrix, recombinant human platelet-derived growth factor (becaplermin), recombinant human epidermal growth factor, recombinant human basic fibroblast growth factor, recombinant human vascular endothelial growth factor, recombinant human lactoferrin, and recombinant human acidic fibroblast growth factor. Topical intervention was the most frequent route of administration. All the trials were underpowered and had a high risk of bias. Pharmaceutical industry sponsored 50% of the trials.Any growth factor compared with placebo or no growth factor increased the number of participants with complete wound healing (345/657 (52.51%) versus 167/482 (34.64%); RR 1.51, 95% CI 1.31 to 1.73; I(2) = 51%, 12 trials; low quality evidence). The result is mainly based on platelet-derived wound healing formula (36/56 (64.28%) versus 7/27 (25.92%); RR 2.45, 95% 1.27 to 4.74; I(2) = 0%, two trials), and recombinant human platelet-derived growth factor (becaplermin) (205/428 (47.89%) versus 109/335 (32.53%); RR 1.47, 95% CI 1.23 to 1.76, I(2)= 74%, five trials).In terms of lower limb amputation (minimum of one toe), there was no clear evidence of a difference between any growth factor and placebo or no growth factor (19/150 (12.66%) versus 12/69 (17.39%); RR 0.74, 95% CI 0.39 to 1.39; I(2) = 0%, two trials; very low quality evidence). One trial involving 55 participants showed no clear evidence of a difference between recombinant human vascular endothelial growth factor and placebo in terms of ulcer-free days following treatment for diabetic foot ulcers (RR 0.64, 95% CI 0.14 to 2.94; P value 0.56, low quality of evidence)Although 11 trials reported time to complete healing of the foot ulcers in people with diabetes , meta-analysis was not possible for this outcome due to the unique comparisons within each trial, failure to report data, and high number of withdrawals. Data on quality of life were not reported. Growth factors showed an increasing risk of overall adverse event rate compared with compared with placebo or no growth factor (255/498 (51.20%) versus 169/332 (50.90%); RR 0.83; 95% CI 0.72 to 0.96; I(2) = 48%; eight trials; low quality evidence). Overall, safety data were poorly reported and adverse events may have been underestimated.

AUTHORS' CONCLUSIONS

This Cochrane systematic review analysed a heterogeneous group of trials that assessed 11 different growth factors for diabetic foot ulcers. We found evidence suggesting that growth factors may increase the likelihood that people will have complete healing of foot ulcers in people with diabetes. However, this conclusion is based on randomised clinical trials with high risk of systematic errors (bias). Assessment of the quality of the available evidence (GRADE) showed that further trials investigating the effect of growth factors are needed before firm conclusions can be drawn. The safety profiles of the growth factors are unclear. Future trials should be conducted according to SPIRIT statement and reported according to the CONSORT statement by independent investigators and using the Foundation of Patient-Centered Outcomes Research recommendations.

What's new in the literature: an update of new research since the original WHS diabetic foot ulcer guidelines in 2006

The objective of the paper was to update the diabetic foot ulcer guidelines that were previously published in 2006. We performed a key word search using MEDLINE and Cochrane reviews for publication between January 2006 and January 2012. Articles that fit the inclusion criteria were reviewed and the previous guidelines were updated.

Effect of platelet-derived growth factor-BB on tissue integration of cross-linked and non-cross-linked collagen matrices in a rat ectopic model

AIM

To test whether or not the network structure and the addition of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) to a chemically cross-linked collagen matrix (CCM)- and a non-cross-linked collagen matrix (NCCM)-influenced tissue integration, angiogenesis, and matrix degradation.

MATERIALS AND METHODS

Four treatment modalities were randomly assigned to four unconnected pouches in the back of 50 rats: (i) CCM-S (soaked in saline), (ii) CCM-P (plus rhPDGF-BB), (iii) NCCM-S (soaked in saline), and (iv) NCCM-P (plus rhPDGF-BB). The animals were sacrificed at 2, 4, 8, 16, and 24 weeks. Descriptive histology and histomorphometric assessments were performed thereby evaluating matrix thickness, the number of vessels (angiogenesis), and connective tissue formation. Means and standard deviations were calculated. Robust linear mixed modeling was used to test the effect of group (NCCM vs CCM), rhPDGF-BB, and time point of sacrifice (2, 4, and 8 weeks).

RESULTS

The thickness of NCCM groups revealed stability (range 440-570 μm) over 8 weeks, while the matrices were no longer present at 16 and 24 weeks. CCM matrices demonstrated a maximal thickness at 2 weeks (2689 ± 187 μm for CCM-S and 2693 ± 389 μm for CCM-P), a decrease of roughly 40% at 8 weeks, but were still present at 16 and 24 weeks. Vascularization of NCCM gradually increased over time with a peak (mean 17.0; SD 1.7) for NCCM-S and NCCM-P (22.0 ± 34.8) at 8 weeks. Angiogenesis in CCM was significantly more pronounced at early time points with a peak at 2 weeks (29.3 ± 16.8 for CCM-S and 30.3 ± 18.4 for CCM-P). No statistically significant effect of rhPDGF-BB was observed for any of the evaluated parameters (all P > 0.05).

CONCLUSIONS

The compact layer (in NCCM) delayed angiogenesis and connective tissue formation, while the spongeous cross-linked matrix of CCM facilitated early vascularization and demonstrated network presence over a longer time span.

Topical and biologic therapies for diabetic foot ulcers

Chronic DFUs are a growing global health concern due to the implied high rates of morbidity and mortality. Standard-of-care modalities sometimes are not sufficient for some recalcitrant ulcers. The use of adjuvant topical therapies including advanced dressings and biologic therapies should be considered in patients whose DFU did not reduce in size after receiving standard care for a period of 4 weeks. These advanced treatments must be used in combination with standard care measures, including debridement, moist wound healing, offloading, and infection control.

Benefit-risk assessment of becaplermin in the treatment of diabetic foot ulcers

Becaplermin is a recombinant platelet-derived growth factor composed of two B chains that is approved for the treatment of neuropathic diabetic foot ulcers extending into or beyond the subcutaneous tissue in patients with adequate arterial perfusion. The aim of this review is to assess the benefits and risks associated with the use of this agent. Randomized controlled trials have provided evidence for the efficacy of becaplermin in increasing healing rates, and cost analyses have repeatedly shown a favourable cost-effectiveness ratio. However, clinical experience has not met these high expectations and becaplermin is not widely used. Moreover, this agent has not been compared with other additional treatment modalities, notably bioengineered skin substitutes and extracellular matrix proteins, and such comparisons are eagerly awaited. Of particular note, increased cancer risk has been reported in patients treated with more than three tubes of becaplermin; thus, this agent should be used only when the anticipated benefits outweigh the potential harm, and with extreme caution in patients with diagnosed malignancy. Finally, longer follow-up data are necessary to shed more light on the potential risk of malignancy in connection with becaplermin use.