Ongoing Clinical Trials

To locate recently conducted and ongoing clinical trials of negative pressure wound therapy, we searched two databases: http://clinicaltrials.gov and http://www.controlled-trials.com. Our searches identified 27 clinical trials with the following status: completed (5), recruiting outside of the U.S. (8); not yet open (4); and ongoing but not recruiting (2). Go to Table 12 for additional information regarding these trials.

ECRI Institute contacted the sponsors of two trials comparing NPWT devices (NCT00583141; NCT00590369); however, we were unable to obtain any further study information at this time.

Table 12. Clinical Trials

Clinicaltrials.gov Identifier or Other Identifier	Sponsor	Study Design	Purpose	Start Date	Expected Completion Date	Estimated Enrollment	Relevance to Key Questions
NCT00583141a	The Cleveland Clinic in collaboration with Smith & Nephew, Inc.	Treatment, randomized, open label, factorial assignment—Versatile One (EZCare) versus KCI VAC negative pressure/vacuum systems	Investigate whether differences can be found in selected outcomes related to wound care, using Versatile One (EZCare) versus KCI VAC negative pressure/vacuum systems.	July 2005	August 2008	50 adults, ages 18 years and older	KQ1
NCT00590369a	The Cleveland Clinic in collaboration with Smith & Nephew, Inc.	Treatment, randomized, open label, factorial assignment—Versatile One (EZCare) versus KCI VAC negative pressure/vacuum systems	Investigate whether differences can be found in selected outcomes related to wound care, using Versatile One (EZCare) versus KCI VAC negative pressure/vacuum systems.	July 2005	August 2008	50 adults, ages 18 years and older	KQ1
NCT00754156d	University of Kentucky	Treatment, non-randomized, open label, parallel assignment, safety/efficacy study—ABRA Abdominal Closure System plus V.A.C. vs. V.A.C. Therapy alone	Compare the efficacy of utilization of the Canica ABRA system combined with the KCI VAC system for closure of open abdomen, versus the utilization of the KCI VAC system alone.	September 2008	July 2010	30 adults, ages 18 years and older	KQ1
NCT00834314	University Hospital Manheim in collaboration with DFG (German Research Foundation), KCI International and Medela Healthcare	Treatment, randomized, open label, active control, parallel assignment, safety/efficacy study—Vacuum-Pack-technique for temporary abdominal closure vs. negative pressure wound therapy for temporary abdominal closure with V.A.C.® Abdominal Dressing System)	Determine whether two vacuum-wound-dressing techniques (the so called "abdominal dressing" versus "vacuum-pack technique") are equally effective in the treatment of open abdomen.	March 2009	June 2010	20 adults, ages 18 years and older	KQ2
NCT00876551	Hannover Medical School, Hannover, Germany	Treatment, non-randomized, open label, uncontrolled, single group assignment, safety/efficacy study - treatment will include a polyurethane foam (KCI) and CNP -125 mmHg using KCI V.A.C.®	Determine the short and long term outcome of endoscopic vacuum assisted closure of intrathoracic postsurgical leaks.	January 2008	December 2012	30 adults ages 18 years and older	KQ3
NCT00847730	KCI USA, Inc.	Supportive care, open label, single group assignment—V.A.C.® GranuFoam®™	Evaluate the ease of use of the V.A.C.® GranuFoam® ™ Bridge dressing on diabetic foot ulcers receiving VAC Negative Pressure Therapy.	February 2009	March 2009	75 adults, ages 18 years and older	KQ3
ISRCTN69032034	University of York, York, UK, in collaboration with the Medical Research Council	RCT—Participants will be randomized to receive NPWT therapy or the comparator treatment (spun hydrocolloid, alginate or foam dressings).	Determine if topical negative pressure therapy is a clinically and cost-effective treatment for grade III/IV pressure ulcers	July 1, 2008	August 31, 2009	50	KQ3
NCT00582179c	University of Alabama at Birmingham	Treatment, randomized, open label, parallel assignment, efficacy study—patients will be treated with a pressure dressing and observation or with a Vacuum-Assisted Closure device (VAC)	Evaluate the use of a negative pressure vacuum device in treating draining hematomas following traumatic injury.	September 2001	December 2008	100 adults, ages 19 years and older	KQ3
NCT00829621	University of Missouri-Columbia in collaboration with Medtronic	Treatment, randomized, open label, active control, parallel assignment—IVAC suction 75 mmHg vs. 125 mmHg	Determine whether or not the negative pressure associated with an IVAC is sufficient to remove BMP-2 from a surgical wound.	December 2008	December 2010	20 adults, ages 18 years and older	KQ3
NCT00582998e	University of Alabama at Birmingham in collaboration with KCI USA, Inc.	Treatment, randomized, open label, parallel assignment, efficacy study—Standard post-operative wound dressing vs. Vacuum-Assisted Closure (VAC) device	Evaluate the use of a negative pressure vacuum device in treating soft tissue injuries and the surgical incision following open reduction and internal fixation of calcaneus, tibial plateau, and pilon fractures.	June 2001	November 2008	189 adults, ages 19 years and older	KQ3
NCT00432965b	KCI USA, Inc.	Treatment, randomized, open label, active control, parallel assignment, safety/efficacy study—Optimized moist wound therapy including physicians use of alginates, hydrogels, hydrocolloids, collagens, etc. vs. VAC therapy	Determine if topical negative pressure therapy delivered by the V.A.C.® device is clinically efficacious and cost effective in the treatment of diabetic foot ulcers.	May 2002	Not provided	338 adults, ages 18 years and older	KQ3
NCT00654641	West Virginia University in collaboration with CAMC Health System	Prevention, randomized, open label, active control, parallel assignment, efficacy study—Negative Pressure wound closure for 72 hours post-operatively vs. Suture closure of subcutaneous tissue and skin stapling and sterile bandage placement	Assess whether applying a source of vacuum (suction) to wounds following Cesarean delivery can reduce the risk of wound complications.	September 2007	November 2010	220 women, ages 18 years and older	KQ3
NCT00582361e	University of Alabama at Birmingham in collaboration with KCI USA, Inc.	Treatment, randomized, open label, parallel assignment, efficacy study—patients will have a standard dressing applied following initial treatment of their open fracture or will have a Vacuum-Assisted Closure (VAC) device applied following initial treatment of their open fracture	Evaluate the use of a negative pressure vacuum device in treating traumatic wounds sustained as a result of an open fracture that requires surgery.	June 2001	March 2008	63 adults, ages 19 years and older	KQ3
NCT00773981	Hvidovre University Hospital in collaboration with Braun Aesculap	Treatment, randomized, open label, parallel assignment, safety/efficacy study—patients treated with a catheter with daily rinsing for a minimum of 7 days or Endoluminal vacuum therapy	Investigate the effects of transrectal vacuum treatment on the healing of anastomotic leakage after rectum resection.	October 2008	October 2011	60 adults, ages 18 years and older	KQ3
NCT00789659d	University of Mississippi Medical Center in collaboration with the Orthopaedic Trauma Association	Prevention, randomized, open label, parallel assignment—postoperative wounds will be dressed with a negative pressure (V.A.C.) dressing or a completely occlusive dressing that is attached to a device that allows a constant negative pressure of 125 mmHg to be generated	Assess the efficacy of VAC therapy on morbidly obese orthopedic trauma patients, specifically those with pelvic ring, acetabular or proximal femur fractures that would require surgery.	January 2009	December 2009	60 adults, ages 18 to 64 years	KQ3
NCT00724750b	University of Chicago	Treatment, randomized, open label, parallel assignment, efficacy study—Gauze suction (G-SUC) Negative Pressure Wound Therapy vs. Vacuum-Assisted Closure Device (VAC) Negative Pressure Wound Therapy	1) Compare the effectiveness of G-SUC and standard VAC therapy with regards to change in wound size over 1-2 weeks and number of patients who are able to clear infection by 4 days. 2) Compare the failure of each method of therapy by documenting the number of dressing that cannot be maintained because of fluid or suction. 3) Measure and compare the cost of the two wound treatments	July 2006	December 2008	120 adults, ages 18 years and older	Studies comparing NPWT to a comparator treatment
NCT00691821d	St. Joseph's Healthcare in collaboration with Ontario Ministry of Health and Long term Care, St. Michael's Hospital, Toronto, Women's College Hospital, Hamilton-Niagara-Haldimand-Brant Community Care Access Centre, Toronto Central Community Care Access Centre	Treatment, randomized, open label, active control, parallel assignment, safety/efficacy study—Participants will receive standard dressings changes as needed. Different dressing types (e.g., silver, simple gauze, hydrogel, foam, creams, gels) will be used dependent on the type of the wound (e.g., dry, wet, and intermediate) vs. Negative Pressure Wound Therapy (Vacuum-Assisted Closure System [V.A.C.® Therapy™])	Assess the difference in the percent reduction in wound surface area, without surgery, of chronic pressure ulcers of the pelvic region for Negative Pressure Wound Therapy (NPWT) at 12 weeks compared to standard dressing. Efficacy, cost-effectiveness, safety and quality of life will also be evaluated for standard wound dressing versus NPWT.	July 2008	March 2011	184 adults, ages 18 years and older	Studies comparing NPWT to a comparator treatment
NCT00243620	Maastricht University Medical Center in collaboration with KCI medical B.V.	Treatment, randomized, open label, active control, parallel assignment, efficacy study—VAC vs. standard wound care according to the SIGN guideline and a multiple-layer compression bandage until complete healing. Four basic types of commercially available wound dressings will be used in this study including hydrogels, alginates, hydrocolloids, and films. The choice of dressing most depended on the ulcer type, the amount of exudate and the physician's preference.	Measure the efficacy of vacuum-assisted closure versus modern wound dressings in the treatment of chronic leg ulcers. Primary focus will be on time-to-complete-healing.	May 2001	May 2004	60 adults up to 85 years of age	Studies comparing NPWT to a comparator treatment
NCT00121537	The University of Texas Health Science Center at San Antonio	Treatment, randomized, open label, active control, single group assignment— Vacuum-assisted closure versus standard wet to dry dressing	Measure the efficacy of vacuum-assisted closure versus standard wet to dry dressing in treating lower leg fasciotomy. Primary focus will be on rate of wound healing.	July 2005	Not provided	30 adults, ages 18 years and older	Studies comparing NPWT to a comparator treatment
NCT00635479	University of Missouri-Columbia	Treatment, randomized, open label, parallel assignment, efficacy study—Vacuum-Assisted Closure (VAC) device for surgical incision vs. Gauze dressing for surgical incision	Examine the efficacy and cost effectiveness of the VAC device in comparison to traditional gauze wound dressing in pelvic fractures and acetabular fractures. Specific focus will be on potential reductions in the incidence of post-operative surgical wound drainage, infections, and hospital stay.	March 2008	December 2008	50 adults, ages 18 years and older	Studies comparing NPWT to a comparator treatment
NCT00224796b	KCI USA, Inc.	Treatment, randomized, open label, active control, parallel assignment, safety/efficacy study—Vacuum-Assisted Closure (V.A.C.®) Therapy vs. moist wound therapy	Compare the effectiveness of Vacuum Assisted Closure (V.A.C.®) Therapy to moist wound therapy of amputation wounds of the diabetic foot.	May 2002	October 2005	146 adults, ages 18 years and older	Studies comparing NPWT to a comparator treatment
NCT00234559	KCI USA, Inc.	Treatment, randomized, open label, active control, parallel assignment—vacuum-assisted closure (VAC®) therapy compared to moist wound therapy	Determine: 1) If vacuum-assisted closure therapy results in altered proteomic expression of angiogenic markers compared to moist wound therapy. 2) If vacuum-assisted closure therapy results in increased angiogenesis compared to moist wound therapy.	September 2005	Not provided	20 adults, ages 18 years and older	Studies comparing NPWT to a comparator treatment
NCT00548314	Association of Dutch Burn Centres	Treatment, randomized, open label, parallel assignment, efficacy study—dermal substitute Matriderm, split skin graft and VAC therapy vs. dermal substitute Matriderm, and split skin graft vs. split skin graft and VAC therapy vs. split skin graft	Determine whether a treatment of full thickness wounds by the dermal substitute Matriderm, split skin graft and VAC treatment will improve scar quality. Additional areas of focus include: increase on the take of graft, improvement of scar assessment scale, scar color/pigmentation and time to complete healing.	October 2007	Not provided	72 adults, ages 18 years and older	Studies comparing NPWT to a comparator treatment
NCT00605189	KCI USA, Inc.	Basic science, randomized, open label, parallel assignment—Powered Suction Pump (VAC Freedom); continuous suction vs. Powered Suction Pump; continuous suction vs. Moist Wound Therapy (Allevyn, Tielle, SoloSite, Curagel); Foam Dressings, Hydrogel Impregnated Gauze, Hydrogel Sheet Dressings	Examine how cellular energies and oxygenation levels are related to various wound treatment therapies in patients with diabetic foot ulcers.	July 2007	August 2008	39 adults with Type II diabetes and chronic diabetic foot ulcers	Studies comparing NPWT to a comparator treatment
NCT00494793	Malmö University Hospital in collaboration with Gävle Hospital, Falu Hospital, Kinetic Concepts, Inc., and The Swedish Research Council	Treatment, open label, uncontrolled, single group assignment, efficacy study—vacuum-assisted wound closure (VAWC) and mesh mediated fascial traction for closure of open abdomens	Prospectively evaluate a combination of vacuum-assisted wound closure and mesh mediated fascial traction for closure of open abdomens.	February 2006	February 2012	10 adult open abdomen patients	Studies comparing NPWT to a comparator treatment
ISRCTN67751142b	Department of Health, London, UK, in collaboration with Hillingdon Hospital NHS Trust	RCT - compression pump and suction therapy versus standard 4 layer bandages	Determine if the use of compression pump and V.A.C. suction therapy provide better management for venous ulcers than standard 4-layer bandages	February 2005	March 2007	NR	Studies comparing NPWT to a comparator treatment
ISRCTN86386707b	VU University Medical Center; funded by NOW-Biopartner First Stage Grant	RCT - 5 day prior wound bed preparation with Vacuum-Assisted Closure therapy (VAC) vs. 5 day prior wound bed preparation with VAC followed by application of Tiscover	Determine if ulcers treated with Tiscover (cultured, autologous skin) will significantly decrease in size resulting in most cases in full healing, compared to the control group (VAC), which is not treated with Tiscover	October 2005	October 2007	100	Studies comparing NPWT to a comparator treatment

^a Device comparison
^b Completed
^c Suspended
^d Not yet open
^e Ongoing, but not recruiting

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Discussion and Conclusions

Based on our defined search strategies and the materials provided by interested parties, no studies directly comparing one NPWT system to another NPWT system were identified that addressed Key Question 1, 2, or 4. Thus, we were not able to identify a significant therapeutic distinction of one NPWT system or component over another through the use of head-to-head comparisons.

In the absence of head-to-head comparison studies, we searched the clinical literature to identify comparison studies of NPWT systems versus a common comparator. We attempted to assess the relative efficacy and/or safety of different NPWT systems using adjusted indirect comparisons. Our review of 40 comparison studies found that all of the controlled trials involved the evaluation of one NPWT device, the V.A.C.® manufactured by KCI. Furthermore, to be considered for inclusion in an indirect comparison, studies must be RCTs and must provide sufficient information to determine their comparability in terms of patient characteristics, patient exclusion/inclusion criteria, methodology, outcome definitions, outcome measures, and application of the comparison treatment. Only nine of the KCI VAC® comparison studies were RCTs and none of these RCTs met the requirements necessary for the indirect comparison option had there been studies of more than one NPWT system.Consequently, at this time the available evidence cannot be used to determine a significant therapeutic distinction of a NPWT system.

None of the 40 comparison studies met the design and conduct requirements to be considered high quality, only seven studies could be considered moderate quality, and the majority of studies (82%) were rated low quality. A low quality study rating calls into question the internal validity of study results and reduces our confidence in the relationship between the interventions and the outcomes. Our conclusions about study quality are also in agreement with the systematic reviews examined in this report. These reviews indicated that the majority of evidence on NPWT was of poor quality.

In their systematic review of clinical studies of NPWT, Peinemann et al.(189) sought to identify unpublished completed or discontinued RCTs to gain a broader knowledge of the NPWT evidence. The authors were concerned that previous systematic review conclusions on efficacy and safety based on published data alone may no longer hold after consideration of unpublished data. The authors invited two NPWT device manufacturers Kinetic Concepts Inc. (V.A.C.®) and BlueSky Medical Group Inc.(BSM)(Versatile 1 Wound Vacuum System) and authors of conference abstracts to provide information on study status and publication status of sponsored trials. Responses were received from 10 of 17 (59%) authors and both manufacturers. BSM, however did not sponsor relevant RCTs and only provided information on case reports. Peienemann et al. concluded that the "lack of access to unpublished study results data raises doubts about the completeness of the evidence base on NPWT."(189)

Our searches did not identify any studies comparing one NPWT system component to another NPWT system component that addressed Key Question 2. No studies of this design were submitted by interested parties. This question was designed to examine studies that compared different dressing sets, tubing, or pumps while maintaining identical components for the other parts of an NPWT system. In particular we were looking for studies that evaluated gauze versus foam dressing sets in various wound types. This would help determine which dressing approach may provide the best potential for wound healing in a variety of wound care situations. The clinical trials now in development or nearing completion examine many different wound types (go to Table 12) but do not address the merits of gauze versus foam within NPWT systems. The recently completed studies from the Cleveland Clinic (NCT00583141; NCT00590369) may address this question but the details of the study design are presently unavailable. The investigators did not wish to disclose any details of the study design prior to publication.

We did identify one high-quality study (116) that compared an electrical pump to a Redon set as vacuum sources while using the same foam dressing set. The findings of this study indicate that the vacuum bottle approach to applying negative pressure to a pressure ulcer is not appropriate. However this study does not directly address any of the questions posed in this report.

Our assessment of adverse events in the evidence base used to address Key Question 3 indicates that the most commonly reported adverse events associated with NPWT are pain, bleeding, and infection. While reports were similar for complications such as bleeding or infection, fewer reports of serious harms (i.e., secondary amputations, graft failure) have been reported when using NPWT compared to patients treated by comparator treatments. Of the 37 studies reporting events, seven (19%) studies described NPWT as a safe treatment. Fewer complications were reported in the NPWT-treated patients than in those receiving other wound therapies in 19 (51%) studies and similar complications were reported in 8 (22%) studies. Due to the lack of studies comparing one NPWT system to another NPWT system, we were unable to determine the severity of adverse events for one NPWT system compared to another (Key Question 4).

Clinical research on NPWT capable of indicating if any one NPWT system or component provides a significant therapeutic distinction requires study design and conduct that will minimize the possibilities for bias. Important study design features that were not typically reported such as concealment of allocation, reporting of randomization methods, use of power analysis to ensure adequate study size, blinding patients and especially wound assessors, and reporting of complete wound healing data will insure the internal validity of study results. None of the studies included in the present review reported that the physicians were blinded to treatment assignment, and only 12% of the studies reported blinding of outcome assessors. In only 7% of studies was there concealment of allocation to treatment, one of the most crucial elements of any randomized controlled trial with failure typically resulting in selection bias.(183,190) Selection bias refers to the presence of systematic differences between the treatment group and the control group at the onset of a study. If the patient groups differ substantially in any way, this may contribute to systematic differences in outcomes that are unrelated to the intervention of interest. The most effective way of guarding against selection bias is to randomly assign patients to treatment groups and fully concealing the treatment allocation process during the randomization.

Findings from one wound type cannot be transferred to another so determining if any one NPWT system or component provides a significant therapeutic distinction relies on numerous high quality studies of several different wound types. In conclusion, the strongest evidence of efficacy will come from properly designed and conducted randomized controlled trials that have been replicated by independent research units.