For the first time NHS patients in Wales with peripheral nerve pain (known as peripheral neuropathic pain) can be treated with a patch containing capsaicin, which can provide at least 12 weeks pain relief following a single 30- or 60-minute application.1,2
The capsaicin patch has received a recommendation from the AWMSG for use as an option for the treatment of peripheral neuropathic pain (PNP) in non-diabetic adults in combination with other medicinal products for pain and in patients who have not received adequate benefit from, or are intolerant to, alternative conventional treatments.1 (See full AWMSG recommendation in notes to editors.)
Peripheral neuropathic pain is caused by damage to pain-sensing nerves. This nerve damage can happen as a result of a range of different diseases, medications or traumatic injuries. This treatment uses a synthetic form of capsaicin, the substance found in chilli peppers which gives them their ‘heat’, to change the way these pain-sensing nerves work in the area of skin affected.3
Exactly how many people suffer from neuropathic pain is not known but estimates for the percentage of the population affected typically range from 1 to 2%, however some sources estimate prevalence to be as high as 8%.4,5 It is a complex and difficult to treat disorder that can have a detrimental effect on a patient’s quality of life.6,7 Studies suggest that, at present, only around a third of patients receiving treatment for neuropathic pain achieve adequate pain relief.8
“Neuropathic pain is often difficult to manage and can have a significant impact on a patient’s quality of life. The pain can be difficult to explain and most people affected describe feelings such as pins and needles, stabbing sensation, burning sensation or sometimes sharp shooting pain like an electric shock,” said Dr Arun Bhaskar, Consultant in Pain Medicine, Anaesthesia and Critical Care, the Christie NHS Foundation Trust. "Many conventional treatments are limited by factors such as side-effects and drug-drug interactions which has led to an interest in localised treatments for peripheral neuropathic pain. A single treatment with the capsaicin patch can give people suffering with peripheral neuropathic pain relief for at least 12 weeks, and gives doctors an effective and well tolerated treatment option for this challenging condition.”
The efficacy and safety of the capsaicin patch have been investigated in a clinical trial programme involving 1,327 patients who received at least one application.2 Pain relief can take up to two weeks to take full effect and relief from pain can be maintained for at least twelve weeks following a single application. Significant reductions in pain were achieved with the capsaicin patch when used alone or in combination with other treatments for pain.2
The most commonly reported side effects with the capsaicin patch are transient and self-limiting application site reactions such as pain and erythema that tend to be mild to moderate in intensity.2
Use of conventional therapies for peripheral neuropathic pain can be restricted by factors such as systemic side effects, drug-drug interactions, slow onset of action, the need for titration and multiple daily dosing.9,10,11 Since the capsaicin patch is designed to act on the affected area, only a small amount of capsaicin is absorbed into the body and there is therefore a low potential for systemic side effects2,9,10 such as sedation and dizziness that may be experienced with other treatments currently prescribed for neuropathic pain.. The capsaicin patch has to be applied by a healthcare professional.
The capsaicin patch is approved by the European Medicines Agency for the treatment of peripheral neuropathic pain in non-diabetic adults either alone or in combination with other medicinal products for pain.2 After pre-treating the painful area with a local anaesthetic to minimise any treatment-related discomfort, the capsaicin patch is applied to the area of pain and left in place for either 30 minutes (when used on the feet) or 60 minutes (when used elsewhere on the body).2 After each application of the capsaicin patch pain relief can be maintained for at least twelve weeks. Treatment can be repeated, if required, after 90 days.2 As a result of treatment-related increases in pain, transient increases in blood pressure may occur during and shortly after the Qutenza treatment.
The patch delivers a high-dose of a synthetic form of capsaicin directly to the hyperactive pain sensing nerves in the skin that are the source of neuropathic pain. Applied to the area of pain, the high concentration of capsaicin contained in the treatment is released into the skin which overstimulates the pain sensing nerves. Overstimulating the pain sensing nerves makes them become “defunctionalised”, effectively making them unresponsive to stimuli that normally cause pain for patients with peripheral neuropathic pain.12
Results from a clinical trial found that 44% of patients with PHN treated with the patch reported ≥ 30% mean decrease in pain over weeks two to twelve following patch application compared with 33% of controls (p=0.05).9 In the same study, twelve weeks post-treatment, 55% of patients treated with capsaicin patch reported improvement in pain relief (as defined by Patient Global Impression of Change [PGIC] scale) compared to 43% of controls (p=0.04).9
A clinical trial of the capsaicin patch in patients with painful HIV neuropathy found that 42% of patients in the 30 minute application group experienced ≥ 30% mean decrease in pain over weeks two to twelve compared with 18% of controls (p= 0.0015).10 These results are noteworthy as the majority of treatments trialled in HIV patients have proven ineffective, even treatments proven to be effective in other neuropathic pain disorders.10
In February 2011 the Scottish Medicines Consortium (SMC) recommended the capsaicin patch for restricted use within NHS Scotland in patients with post-herpetic neuralgia (PHN) who have not achieved adequate pain relief from, or who have not tolerated, conventional first and second line treatments.13 The capsaicin patch has not been reviewed by the National Institute for Health and Clinical Excellence (NICE).
Full AWMSG Recommendation
Capsaicin patch (Qutenza) is not recommended for use alone for the treatment of peripheral neuropathic pain (PNP) in non-diabetic adults.
Capsaicin patch (Qutenza) is recommended as an option for restricted use within NHS Wales for the treatment of peripheral neuropathic pain (PNP) in non-diabetic adults in combination with other medicinal products for pain and in patients who have not received adequate benefit from, or are intolerant to, alternative conventional treatments.