Fundamentals of randomized clinical trials in wound care: Design and conduct

An Open-Label, Interventional, Prospective, Real-World Evidence Study to Evaluate a Multimodal Wound Matrix in Patients with Refractory Wounds

Objective: The objective of this open-label, interventional, prospective clinical study was to evaluate the effectiveness of a multimodal wound matrix (MWM) in moving chronic, nonhealing wounds that had failed prior therapies onto a healing trajectory. The overall response rate was the proportion of subjects who had greater than 40% reduction in size after 4 weeks of treatment. Secondary objectives included the percentage area reduction (PAR) after 4 and 12 weeks, incidence of ulcer closing, and changes in quality of life. Approach: An open-label, interventional, prospective cohort, real-world evidence study was conducted following the STROBE criteria. Criteria included chronic nonhealing wounds of multiple etiologies in subjects with extensive comorbidities. Results were compared with data from the U.S. Wound Registry. Results: A total of 111 subjects entered the screening phase and 64 were treated. Fifty-three wounds were eligible for the dataset that included 18 diabetic foot ulcers, 19 venous leg ulcers, 2 pressure injuries, 1 surgical, 1 lower extremity wound, and 12 unclassified etiologies. The objective response rate was 42%. The 4-week PAR was 34%. The 12-week PAR was 66%. Eighteen wounds closed by week 12. Innovation: MWM is a formulation technology developed to address the major obstacles that prevent healing. Results were evaluated in a patient population with extensive comorbidities that had failed prior treatments and would be generally excluded from controlled trials. Conclusion: The results from this study support the contention that MWM achieves substantial clinical improvement in a complex patient population not enrolled in clinical trials and demonstrates an advancement in wound management.

[Design of a clinical study to demonstrate the therapeutic benefit of another wound treatment product]

BACKGROUND

Due to new legal requirements, a patient-relevant benefit for other wound treatment products (sPW) must be demonstrated through clinical studies if reimbursement at the expense of the statutory health insurance is sought in the non-inpatient sector.

METHOD

An interdisciplinary group with expertise in clinical wound care has developed general recommendations for the design of suitable studies. In addition to regulatory documents, previous studies that have already been recognized as proof of benefit in other areas served as a basis.

RESULTS

Randomized controlled trials that cover at least the most common types of chronic wounds (arterial, venous, diabetic or pressure sore) are recommended as the best method for gathering evidence. Despite the heterogeneous etiology of chronic wounds, the results should also be transferable to other wound types. The test intervention does not usually consist of the sPW alone, but of a combined wound treatment that follows a treatment plan that is as clearly defined as possible. In the comparison group, all wound treatment options (besides the sPW) must also be available and used according to a similar predefined treatment plan. Depending on the intended purpose and treatment goal, complete wound closure should, if possible, be recorded as the cardinal - although not always as the primary - endpoint. In justified cases, e.g. in the case of intermediate use as part of phase-appropriate wound therapy for chronic wounds, a significant reduction in the wound area can also be considered for benefit assessment. Quality of life (e.g. pain) can also justify a benefit and can therefore be recorded as a primary outcome parameter in clinical trials. The duration of the clinical trial should be adapted to the central endpoints, the medical or nursing goal of wound care and the intended purpose of the sPW. A benefit does not always arise from microbiological, physiological, laboratory or histological parameters or imaging findings.

Bringing innovative wound care polymer materials to the market: Challenges, developments, and new trends

The development of innovative products for treating acute and chronic wounds has become a significant topic in healthcare, resulting in numerous products and innovations over time. The growing number of patients with comorbidities and chronic diseases, which may significantly alter, delay, or inhibit normal wound healing, has introduced considerable new challenges into the wound management scenario. Researchers in academia have quickly identified promising solutions, and many advanced wound healing materials have recently been designed; however, their successful translation to the market remains highly complex and unlikely without the contribution of industry experts. This review article condenses the main aspects of wound healing applications that will serve as a practical guide for researchers working in academia and industry devoted to designing, evaluating, validating, and translating polymer wound care materials to the market. The article highlights the current challenges in wound management, describes the state-of-the-art products already on the market and trending polymer materials, describes the regulation pathways for approval, discusses current wound healing models, and offers a perspective on new technologies that could soon reach consumers. We envision that this comprehensive review will significantly contribute to highlighting the importance of networking and exchanges between academia and healthcare companies. Only through the joint of these two actors, where innovation, manufacturing, regulatory insights, and financial resources act in harmony, can wound care products be developed efficiently to reach patients quickly and affordably.

The Discovery and Development of Natural-Based Biomaterials with Demonstrated Wound Healing Properties: A Reliable Approach in Clinical Trials

Current research across the globe still focuses strongly on naturally derived biomaterials in various fields, particularly wound care. There is a need for more effective therapies that will address the physiological deficiencies underlying chronic wound treatment. The use of moist bioactive scaffolds has significantly increased healing rates compared to local and traditional treatments. However, failure to heal or prolonging the wound healing process results in increased financial and social stress imposed on health institutions, caregivers, patients, and their families. The urgent need to identify practical, safe, and cost-effective wound healing scaffolding from natural-based biomaterials that can be introduced into clinical practice is unequivocal. Naturally derived products have long been used in wound healing; however, clinical trial evaluations of these therapies are still in their infancy. Additionally, further well-designed clinical trials are necessary to confirm the efficacy and safety of natural-based biomaterials in treating wounds. Thus, the focus of this review is to describe the current insight, the latest discoveries in selected natural-based wound healing implant products, the possible action mechanisms, and an approach to clinical studies. We explore several tested products undergoing clinical trials as a novel approach to counteract the debilitating effects of impaired wound healing.

The wound healing effect of local leukocyte platelet-rich plasma after total hip arthroplasty: A randomized controlled trial

Rapid wound closure is important after arthroplasty procedures to prevent postoperative complications. Platelets are rich in growth factors and leukocytes contribute to innate immunity. We hypothesized that topical leukocyte platelet-rich plasma (L-PRP) derived from the blood of patients would be beneficial to wound healing. In this randomized controlled trial, patients subjected to elective total hip arthroplasty (THA) were assigned by concealed allocation either L-PRP application onto the sutured fascia or no application (control) after the THA intervention. In addition, all patients received 1.5 g protein/kg, 5 g L-arginine, 500 mg vitamin C and 44 mg zinc daily over the 4-week postoperative period to obtain optimal nutrition. The primary endpoint was complete healing of the skin incision. The secondary endpoints were blood transfusions, length of hospital stay, pain and wound infections. Sixteen patients in the L-PRP group and 17 patients in the control group completed the trial. L-PRP treatment accelerated complete wound healing after 3 weeks (seven in the L-PRP group vs. zero in the control group, p = 0.003) and after 4 weeks (12 in the L-PRP group vs. six in the control group, p = 0.037). No postoperative superficial wound infections occurred within 4 weeks, and there were no significant differences in the other secondary outcomes. L-PRP generated in 10 sex-matched healthy volunteers revealed increased concentrations of platelets (5.8-fold) and leukocytes (2.3-fold) compared with those in whole blood. Furthermore, the concentration of keratinocyte mitogen epidermal growth factor in L-PRP (380 ± 130 pg/ml, mean ± SD) was higher (p < 0.001) than that in serum (130 ± 26 pg/ml). In conclusion, a single intraoperative local application of L-PRP promoted wound healing after THA, possibly mediated by EGF receptor agonists.

Rationale for participation in venous leg ulcer clinical research: Patient interview study

Recruitment to wound care clinical trials is challenging and a better understanding of patient decisions to participate has the potential to influence recruitment success. We conducted 31 semi-structured telephone interviews of patients who participated in the Aspirin in Venous Leg Ulcer (ASPiVLU) randomised controlled trail (RCT) or ASPiVLU cohort study. Data were coded and analysed using thematic analysis. We identified four key themes: (a) "I participated to help others"; (b) "I participated in research to thank those who cared for me"; (c) "I participated to receive better care"; and (d) "I participated to have a say on what works." These themes became basic elements for the Rationale for Research Participation Framework that we have developed to improve the participant recruitment process for clinical trials in wound care.

Negative pressure wound therapy: A systematic review of randomized controlled trials from 2000 to 2017

BACKGROUND

Negative pressure wound therapy (NPWT) proposes to provide better wound healing than standard wound management. Evidence quality of randomized controlled trials (RCTs) varies.

METHODS

We included participants with any kind of wounds and commercial as well as the homemade NPWT system. Comparators were any other wound dressing including variant NPWTs. We included RCTs randomizing patients or wounds in parallel or crossover designs. We searched PubMed and Cochrane Library on January 03, 2018. We assessed the risk of bias according to Cochrane and appropriateness of clinical endpoints according to the Food and Drug Administration (FDA).

RESULTS

We included 93 RCTs originating in 30 countries, 70 studies on open wounds and 23 studies on closed wounds. With respect to random sequence generation, we judged an unclear or high risk of bias in 50% (47 of 93) studies. With respect to allocation concealment, we judged an unclear or high risk of bias in 90% (84 of 93). We identified 41% (38 of 93) studies that based their conclusion on not appropriate endpoints.

CONCLUSIONS

High risk of bias concerning random sequence generation and allocation concealment limited the credibility of the majority of 93 included RCTs on NPWT. A low risk of bias can and should be achieved with both items, and we recommend to align future RCTs to Cochrane. Many primary clinical endpoints were deemed not valid for making inferences on the efficacy of NPWT. We recommend using patient-centered endpoints as requested by the FDA and suggested in the present systematic review.

Understanding the Hawthorne effect in wound research-A scoping review

The Hawthorne Effect (HE) is considered a methodological artefact in research, although its definition and influence on research outcomes lack consensus. This review explored how this term has been mentioned and discussed in the area of wound research. A scoping review was conducted on ProQuest Central, Scopus, EbscoHost, and online databases of indexed wound journals using the methodological framework by Arksey and Malley. A review protocol was applied to detail key terms, truncation and Boolean operators, and inclusion and exclusion criteria. Search findings were reported using PRISMA guidelines. A total of 38 articles reporting primary evidence were identified. Three themes emerged from the review: wound researchers' awareness of HE, the acknowledgement of the existence or otherwise of HE, and the mentioning of HE in passing. These results reflect a lack of attention to and understanding and awareness of the HE in the area of wound research. It is suggested that the HE receives more attention as a methodological concern, and its potential influence is considered and mitigated when planning future studies. Recommendations are provided to minimise the impact of the HE on the rigour of the research and confidence afforded to research findings.

Is additional hyperbaric oxygen therapy cost-effective for treating ischemic diabetic ulcers? Study protocol for the Dutch DAMOCLES multicenter randomized clinical trial?

BACKGROUND

The value of hyperbaric oxygen therapy (HBOT) in the treatment of diabetic ulcers is still under debate. Available evidence suggests that HBOT may improve the healing of diabetic ulcers, but it comes from small trials with heterogeneous populations and interventions. The DAMOCLES-trial will assess the (cost-)effectiveness of HBOT for ischemic diabetic ulcers in addition to standard of care.

METHODS

In a multicenter randomized clinical trial, including 30 hospitals and all 10 HBOT centers in the Netherlands, we plan to enroll 275 patients with Types 1 or 2 diabetes, a Wagner 2, 3 or 4 ulcer of the leg present for at least 4 weeks, and concomitant leg ischemia, defined as an ankle systolic blood pressure of <70 mmHg, a toe systolic blood pressure of <50 mmHg or a forefoot transcutaneous oxygen tension (TcpO2) of <40 mmHg. Eligible patients may be candidates for revascularization. Patients will be randomly assigned to standard care with or without 40 HBOT-sessions.

RESULTS

Primary outcome measures are freedom from major amputation after 12 months and achievement of, and time to, complete wound healing. Secondary endpoints include freedom from minor amputations, ulcer recurrence, TcpO2 , quality of life, and safety. In addition, we will assess the cost-effectiveness of HBOT for this indication.

CONCLUSION

The DAMOCLES trial will be the largest trial ever performed in the realm of HBOT for chronic ulcers, and it is unique for addressing patients with ischemic diabetic foot ulcers who may also receive vascular reconstructions. This matches the treatment dilemma in current clinical practice.

What Do Patients Want? Patient Preference in Wound Care

Patient preferences are statements made or actions taken by consumers that reflect their desirability of a range of health options. The concept occupies an increasingly prominent place at the center of healthcare reform, and is connected to all aspects of healthcare, including discovery, research, delivery, outcome, and payment. Patient preference research has focused on shared decisions, decisional aids, and clinical practice guideline development, with limited study in acute and chronic wound care populations. The wound care community has focused primarily on patient focused symptoms and quality of life measurement. With increasing recognition of wound care as a medical specialty and as a public health concern that consumes extensive resources, attention to the preferences of end-users with wounds is necessary. This article will provide an overview of related patient-centered concepts and begin to establish a framework for consideration of patient preference in wound care.

Human Wound-Healing Research: Issues and Perspectives for Studies Using Wide-Scale Analytic Platforms

Significance: Revealing the basic mechanisms in the healing process and then regulating these processes for faster healing or to avoid negative outcomes such as infection or scarring are fundamental to wound research. The normal healing process is basically known, but to thoroughly understand the very complex aspects involved, it is necessary to characterize the course of events at a higher resolution with the latest molecular techniques and methodologies. Recent Advances: Various animal models are used in wound-healing research. Rodent and pig models are the ones most often used, probably because of pre-existing sophisticated research methodologies and as the proper care and ethical use of these species are highly developed and organized to serve science throughout the world. Critical Issues: Since several animal models are used, their anatomical and physiological differences varyingly affect the translation of results on healing mechanisms. Hence, to avoid species-specific misinformation, more ways to study wound healing directly in humans are needed. Future Directions: Fortunately, novel techniques have enabled high-end molecular-level research even from small samples of tissue. Since these methods require only a small amount of patient skin, they make it possible to study wound healing directly in humans.

Funding source and the quality of reports of chronic wounds trials: 2004 to 2011

BACKGROUND

Critical commentaries suggest that wound care randomised controlled trials (RCTs) are often poorly reported with many methodological flaws. Furthermore, interventions in chronic wounds, rather than being drugs, are often medical devices for which there are no requirements for RCTs to bring products to market. RCTs in wounds trials therefore potentially represent a form of marketing. This study presents a methodological overview of chronic wound trials published between 2004 and 2011 and investigates the influence of industry funding on methodological quality.

METHODS

A systematic search for RCTs for the treatment of chronic wounds published in the English language between 2004 and 2011 (inclusive) in the Cochrane Wounds Group Specialised Register of Trials was carried out.Data were extracted on aspects of trial design, conduct and quality including sample size, duration of follow-up, specification of a primary outcome, use of surrogate outcomes, and risks of bias. In addition, the prevalence of industry funding was assessed and its influence on the above aspects of trial design, conduct and quality was assessed.

RESULTS

A total of 167 RCTs met our inclusion criteria. We found chronic wound trials often have short durations of follow-up (median 12 weeks), small sample sizes (median 63), fail to define a primary outcome in 41% of cases, and those that do define a primary outcome, use surrogate measures of healing in 40% of cases. Only 40% of trials used appropriate methods of randomisation, 25% concealed allocation and 34% blinded outcome assessors. Of the included trials, 41% were wholly or partially funded by industry, 33% declared non-commercial funding and 26% did not report a funding source. Industry funding was not statistically significantly associated with any measure of methodological quality, though this analysis was probably underpowered.

CONCLUSIONS

This overview confirms concerns raised about the methodological quality of RCTs in wound care and illustrates that greater efforts must be made to follow international standards for conducting and reporting RCTs. There is currently minimal evidence of an influence of industry funding on methodological quality although analyses had limited power and funding source was not reported for a quarter of studies.