Aspirin for Venous Ulcers: Randomised Trial (AVURT): study protocol for a randomised controlled trial

Aspirin versus placebo for the treatment of venous leg ulcers-a phase II, pilot, randomised trial (AVURT)

BACKGROUND

Venous leg ulcers (VLUs) can take many months to heal and 25% fail to heal. The main treatment for venous leg ulcers is compression therapy and few additional therapies exist. Two previous trials indicated that low-dose aspirin may improve healing time, but these trials were insufficiently robust.

METHODS

A multi-centred, pilot, phase II, randomised, double blind, parallel-group, placebo-controlled, efficacy trial (RCT) was conducted to determine: if aspirin improves VLU healing time; the safety of aspirin in this population; treatment compliance; and the feasibility of recruitment to a phase III trial. We recruited patients from secondary care who were aged ≥ 18 years, had a chronic VLU and not regularly taking aspirin. Participants were randomly assigned (1:1) to receive 300 mg of daily aspirin or placebo in addition to standard care, which consisted of multi component compression therapy aiming to deliver 40 mmHg at the ankle where possible. The randomisation list was stratified by ulcer size (≤ 5 cm2 or > 5 cm2). The primary endpoint was time to ulcer healing, which was defined as 'complete epithelial healing in the absence of scab (eschar) with no dressing required'. Safety outcomes were assessed in all participants who received at least one dose of the study drug.

RESULTS

Twenty-seven patients were recruited from eight sites (target 100 patients). A short time-frame to recruit and a large number of patients failing to meet the eligibility criteria were the main barriers to recruitment. There was no evidence of a difference in time to healing of the reference ulcer following adjustment for log ulcer area and duration (hazard ratio 0.58, 95% confidence interval 0.18 to 1.85; p = 0.357). One expected serious adverse event related to aspirin was recorded. A number of options to improve recruitment were explored.

CONCLUSIONS

There was no evidence that aspirin was effective in expediting the healing of chronic VLUs. However, the analysis was underpowered due to the low number of participants recruited. The trial design would require substantial amendment in order to progress to a phase III (effectiveness) trial.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT02333123. Registered on 5 November 2014.

Venous thromboembolism prophylaxis using the Caprini score

Venous thromboembolism (VTE) including pulmonary embolism (PE) and deep vein thrombosis (DVT) is one of the leading causes of preventable cardiovascular disease in the United States (US) and is the number one preventable cause of death following a surgical procedure. Post-operative VTE is associated with multiple short and long-term complications. We will focus on reviewing the many faces of VTE in detail as they represent common challenging scenarios in clinical practice.

AVURT: aspirin versus placebo for the treatment of venous leg ulcers - a Phase II pilot randomised controlled trial

BACKGROUND

Venous leg ulcers (VLUs) are the most common cause of leg ulceration, affecting 1 in 100 adults. VLUs may take many months to heal (25% fail to heal). Estimated prevalence is between 1% and 3% of the elderly population. Compression is the mainstay of treatment and few additional therapies exist to improve healing. Two previous trials have indicated that low-dose aspirin, as an adjunct to standard care, may improve healing time, but these trials were insufficiently robust. Aspirin is an inexpensive, widely used medication but its safety and efficacy in the treatment of VLUs remains to be established.

OBJECTIVES

Primary objective - to assess the effects of 300 mg of aspirin (daily) versus placebo on the time to healing of the reference VLU. Secondary objectives - to assess the feasibility of leading into a larger pragmatic Phase III trial and the safety of aspirin in this population.

DESIGN

A multicentred, pilot, Phase II randomised double-blind, parallel-group, placebo-controlled efficacy trial.

SETTING

Community leg ulcer clinics or services, hospital outpatient clinics, leg ulcer clinics, tissue viability clinics and wound clinics in England, Wales and Scotland.

PARTICIPANTS

Patients aged ≥ 18 years with a chronic VLU (i.e. the VLU is > 6 weeks in duration or the patient has a history of VLU) and who are not regularly taking aspirin.

INTERVENTIONS

300 mg of daily oral aspirin versus placebo. All patients were offered care in accordance with Scottish Intercollegiate Guidelines Network (SIGN) guidance with multicomponent compression therapy aiming to deliver 40 mmHg at the ankle when possible.

RANDOMISATION

Participants were allocated in a 1 : 1 (aspirin : placebo) ratio by the Research Pharmacy, St George's University Hospitals NHS Foundation Trust, using a randomisation schedule generated in advance by the investigational medicinal product manufacturer. Randomisation was stratified according to ulcer size (≤ 5cm² or > 5cm²).

MAIN OUTCOME MEASURE

The primary outcome was time to healing of the largest eligible ulcer (reference ulcer).

FEASIBILITY RESULTS – RECRUITMENT

27 patients were recruited from eight sites over a period of 8 months. The target of 100 patients was not achieved and two sites did not recruit. Barriers to recruitment included a short recruitment window and a large proportion of participants failing to meet the eligibility criteria.

RESULTS

The average age of the 27 randomised participants (placebo, n = 13; aspirin, n = 14) was 62 years (standard deviation 13 years), and two-thirds were male (n = 18). Participants had their reference ulcer for a median of 15 months, and the median size of ulcer was 17.1 cm². There was no evidence of a difference in time to healing of the reference ulcer between groups in an adjusted analysis for log-ulcer area and duration (hazard ratio 0.58, 95% confidence interval 0.18 to 1.85; p = 0.357). One expected, related serious adverse event was recorded for a participant in the aspirin group.

LIMITATIONS

The trial under-recruited because many patients did not meet the eligibility criteria.

CONCLUSIONS

There was no evidence that aspirin was efficacious in hastening the healing of chronic VLUs. It can be concluded that a larger Phase III (effectiveness) trial would not be feasible.

TRIAL REGISTRATION

Clinical Trials.gov NCT02333123; European Clinical Trials Database (EudraCT) 2014-003979-39.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 55. See the NIHR Journals Library website for further project information.

Evidence-Based Clinical Practice Points for the Management of Venous Ulcers

Venous ulcer is an extremely common aetiology of lower extremity ulceration, which affects approximately 1% population in most of the countries, and the incidence rate increases with age and female gender. Proper assessment and diagnosis of both the patient and ulcer are inevitable in order to differentiate venous ulcers from other lower extremity ulceration and to frame an adequate and individualised management plan. Venous ulcers generally persist for weeks to many years and are typically recurrent in nature. This consensus aims to present an evidence-based management approach for the patients with venous ulcers. Various management options for venous ulcers include compression therapy, minimally invasive procedures like sclerotherapy and ablation techniques, surgical procedures, debridement and medical management with micronised purified flavonoid fraction (MPFF). Compression therapy is the mainstay treatment for venous ulcer. However, in failure cases, surgery can be preferred. Medical management with MPFF as an adjuvant therapy to standard treatment has been reported to be effective and safe in patients with venous ulcer. In addition to standard therapy, diet and lifestyle modification including progressive resistance exercise, patient education, leg elevation, weight reduction, maintaining a healthy cardiac status and strong psychosocial support reduces the risk of recurrence and improves the quality of life in patients with venous ulcer.