A skin patch that delivers an 8% capsaicin formulation intradermally and that first received US Food and Drug Administration approval in 2009 for the treatment of postherpetic pain now has agency approval for the treatment of neuropathic pain associated with diabetic peripheral neuropathy of the feet in adults, according to a company announcement on July 21.
The patch, marketed as Qutenza, is a topical, nonsystemic, nonopioid pain treatment and is "the first and only treatment of its kind to deliver prescription strength capsaicin directly into the skin," according to Averitas Pharma, which will market the patch in the United States.
"Pain associated with diabetic neuropathy is an extremely challenging condition to diagnose, treat and manage effectively, which has a significant quality of life impact for many patients," said David M. Simpson, MD, lead investigator of the STEP study that established the patch's efficacy in this setting. He is professor of neurology at the Icahn School of Medicine at Mount Sinai, New York City.
"In addition, patients are dissatisfied with unresolved pain and the side effects associated with current systemic treatments," noted Simpson in the company press release.
The STEP pivotal trial randomly assigned 389 diabetic neuropathy patients to receive a single, 30-minute application of either the active, capsaicin-releasing patch or a placebo patch to a painful area on their feet. The primary efficacy endpoint was the average change in daily pain score on the Numeric Pain Rating Scale during weeks 2–8 following the single treatment.
Results showed an overall average 27% decline from baseline for patients who received active treatment and an average 21% drop from baseline among control patients, a statistically significant difference (J Pain. 2017 Jan 1;18:42-53).
There were no new safety problems and no treatment discontinuations because of drug-related treatment-emergent adverse effects, including serious adverse effects that were considered drug related. The most common adverse effects from treatment were application-site reactions, most often application-site pain, which occurred in 34% of patients treated with the active patch and in 8% treated with a placebo patch.
In routine practice, patch application usually occurs in a physician's office. According to the label, application time can be up to 60 minutes, and repeat treatment is possible every 3 months. Topical capsaicin reversibly desensitizes and functionally impairs a skin receptor, the transient receptor potential vanilloid 1 receptor, which plays a key role in pain signaling.
The Quetenza patch has been available in the European Union for the treatment of adult patients with diabetes who have peripheral neuropathic pain, either alone or in combination with other medicinal products for pain, for 5 years.
The STEP trial was sponsored by Astellas Pharma. The 8% capsaicin skin patch (Qutenza) is marketed worldwide by Grünenthal and in the United States by Averitas Pharma, a Grünenthal subsidiary. Simpson has consulted for and received research grants from Astellas Pharma, Acorda, and Viromed and has received speaking honoraria from Acorda.
Cite this: FDA OKs Capsaicin Patch for Diabetic Neuropathy Foot Pain - Medscape - Jul 23, 2020.