Clinical and technical evidence

Advice

Published evidence
Overall assessment of the evidence
Recent and ongoing studies

Clinical and technical evidence

A literature search was carried out for this briefing in accordance with the interim process and methods statement. This briefing includes the most relevant or best available published evidence relating to the clinical effectiveness of the technology. Further information about how the evidence for this briefing was selected is available on request by contacting mibs@nice.org.uk.

Published evidence

Three studies, including data from a total of 856 people with venous leg ulcers, are summarised in this briefing.

Table 2 summarises the clinical evidence as well as its strengths and limitations.

Overall assessment of the evidence

The studies in the table include 2 randomised comparisons and 1 retrospective observational comparative study using routinely collected NHS data. In 1 RCT (Moffatt et al. 2008), there was no significant difference in wound healing between Coban 2 and Profore, but Coban 2 performed better in slipping, health-related quality of life and patient preference. The second RCT (Mosti et al. 2011) was done in Italy and compares Coban 2 with the Unna boot, which is not routinely used in the NHS. Coban 2 slipped more but there were no significant differences in wound healing, pain or patient comfort. The observational study (Guest et al. 2015) uses data collected in the NHS and shows that Coban 2 performs best for ulcer healing and health-related quality of life compared with Profore and UrgoKTwo. Patient characteristics were not reported.

All 3 studies included in the briefing were funded by the company and so may be prone to bias. Only 1 study followed people until complete wound healing; the other 2 studies followed people for 8 weeks or 6 months. With the right treatment, venous leg ulcers tend to heal within 3 to 4 months, meaning that a follow-up period of less than 6 months is likely too short.

Table 2 Summary of selected studies

Moffatt et al. (2008)
Study size, design and location	81 people with venous leg ulcers were enrolled in an 8-week, randomised, open-label, crossover clinical trial. Location: 10 centres in UK.
Intervention and comparator(s)	Coban 2 and Profore 4-layer compression bandage.
Key outcomes	Primary outcome: Mean bandage slip at each dressing change: 2.48 cm for Coban 2 and 4.17 cm for Profore. Secondary outcome: No significant differences in wound healing between the bandages. Significantly higher HRQoL scores (physical symptoms and daily living) for Coban 2 compared with Profore. Patient preference was recorded as: 72% Coban 2; 22% Profore; and 6% no preference.
Strengths and limitations	This study was designed to collect outcomes relevant to patient experience, for example: bandage slip and associated HRQoL. The study did not collect data on complete wound healing. Data are collected from an NHS setting. 3M provided financial support for this study.
Mosti et al. (2011)
Study size, design and location	100 people with venous leg ulcers were enrolled in a prospective, multicentre RCT. Follow-up appointments weekly for 3 months, followed by monthly appointments until full wound closure. Location: Italy.
Intervention and comparator(s)	Coban 2 (50 people) and Unna boot (50 people).
Key outcomes	Primary outcome: No significant difference in wound healing, pain or exudate. Secondary outcome: No significant difference in patient comfort between the 2 devices. Bandage slip and skin scaling happened significantly more often with Coban 2 than with Unna boot (11 versus 5 for slip and 21 versus 7 for skin scaling). The authors reported that Coban 2 is easier to apply and remove than Unna boot.
Strengths and limitations	The Unna boot is not routinely used in the UK. The authors describe a 'modified Unna boot' but do not give detail on the modifications. The patient population in the study was 76% female. 3M provided Coban 2 free of charge.
Guest et al. (2015)
Study size, design and location	The case records (the Health Improvement Network database) of 675 people with venous leg ulcers were used to inform a retrospective analysis. Location: UK.
Intervention and comparator(s)	Coban 2 (250 people), Ktwo 2-layer compression bandage (250 people) and Profore 4-layer compression bandage (175 people).
Key outcomes	During the 6-month study period, 51% of venous leg ulcers treated with Coban 2 had healed compared with 40% for Ktwo and 28% for Profore. HRQoL was highest in the Coban-2 group at 0.374 QALY compared with 0.368 QALY for Ktwo and 0.353 QALY for Profore.
Strengths and limitations	This study was funded by a research grant from the company. Data are collected from the NHS. The THIN data cut off at 6 months after first treatment with compression. The authors do not report patient characteristics but stated that the 'average patient' had been considered in the analyses.
Abbreviations: HRQoL, health-related quality of life; QALY, quality-adjusted life years.

Recent and ongoing studies

The following ongoing trials were identified:

Cost Evaluation of Venous Leg Ulcers Management, NCT02728986; location: France; study completion: December 2017; sponsor: 3M.

Randomized Clinical Trial (RCT) to Compare the Efficacy of Coban 2 Versus SSB in the Treatment of Venous Leg Ulcers, NCT00558662; location: UK Belgium, Germany and Netherlands; study completion: November 2011; no results posted; sponsor: 3M.