Capsaicin 8% patch: a clinical study in Diabetic Peripheral Neuropathy
Research type
Research Study
Full title
Pain relief with disease modification by Capsaicin 8% patch: a clinical study in Diabetic Peripheral Neuropathy
IRAS ID
239464
Contact name
Praveen Anand
Contact email
Sponsor organisation
Joint Research Compliance Office, Imperial College London and Imperial College Healthcare NHS Trust
Eudract number
2017-004746-17
Duration of Study in the UK
2 years, 0 months, 1 days
Research summary
Research Summary
Current treatments for painful diabetic peripheral neuropathy (nerve damage) have limited efficacy with significant side-effects, and there are no approved treatments to prevent or modify the progression of nerve damage.
Capsaicin 8% patch (skin plaster) is a novel effective, safe and well tolerated topical treatment, licensed for pain in painful diabetic peripheral neuropathy: a single application for 30 minutes can produce pain relief for 3 months or longer.
The aim is to assess objectively whether repeated applications of capsaicin 8% patch, which reduce pain, also modify the underlying neuropathy (repair the nerve damage). We propose to test that repeated applications may increase the regeneration of the nerve fibres as a result of “pruning” the damaged nerve endings, based on recent clinical observations in painful diabetic peripheral neuropathy. Patients will receive capsaicin 8% patch 3-monthly repeat treatments as licensed plus standard of care (SOC), or SOC alone, over a maximum period of 1 year. Outcomes will be evaluated using standard measures including pain scores, sensory tests, and serial skin punch biopsies (3 mm).
This study will provide insights into mechanisms of pain and nerve regeneration, and indicate the potential of capsaicin 8% patch for nerve repair (disease modification). Our aim is to demonstrate that a new effective, safe and well-tolerated topical treatment, the capsaicin 8% patch (skin plaster), is particularly suited for chronic pain from nerve damage in diabetic patients. Our studies may lead to its use as the first-line treatment for pain from nerve damage, and the first treatment to change the course of Painful Diabetic Neuropathy.
Summary of Results
We have conducted a study to assess the beneficial effects of the Capsaicin 8% patch in diabetic peripheral neuropathy. We have shown pain relief, functional improvement and regeneration of nerve fibres, for an increasing major unmet global need. There is currently no licensed treatment for nerve regeneration and restoration in diabetic or any other peripheral neuropathy.
The study initially recruited patients with painful diabetic neuropathy, of which 35 were to be treated with the Capsaicin 8% patch and 15 received standard care alone. The study was later extended to include 25 patients with non-painful diabetic neuropathy, due to the evidence of nerve regeneration in the painful diabetic neuropathy group, in addition to pain relief.
Improvement of nerve fibres density and regeneration of nerve fibres were observed in both painful and non-painful diabetic neuropathy patients after a 30-minute Capsaicin 8% patch application to the feet and distal calf. Further, there was an improvement in sensory function, and neuropathic pain in the painful neuropathy group. In contrast, and in accord with previous studies, the control group (standard of care alone) showed a decrease in regenerating nerve fibres, as expected with the condition's natural history.
We regard this treatment outcome as “disease-modification”, which is supported by our two published studies in patients with chemo-induced peripheral neuropathy (Anand et al., J Pain Res. 2019) and Non-freezing cold injury / Trench Foot (Anand et al., Front Neurol. 2021). Capsaicin 8% patch treatment significantly increased regeneration and restoration of small sensory nerve fibres, in addition to relief of neuropathic pain.
Our landmark results provide an exciting new prospect for patients with diabetic peripheral neuropathy, which affects their quality of life. It also has implications for the prevention of diabetic foot ulcers, for which loss of nerve fibres and their dysfunction is the major cause.REC name
East of England - Cambridgeshire and Hertfordshire Research Ethics Committee
REC reference
17/EE/0498
Date of REC Opinion
19 Jan 2018
REC opinion
Further Information Favourable Opinion