Mechanism- and experience-based strategies to optimize treatment response to the capsaicin 8% cutaneous patch in patients with localized neuropathic pain

Abstract

The capsaicin 8% cutaneous patch is an emergent new treatment option for patients with peripheral neuropathic pain. In randomized controlled clinical studies relevant pain relief for 12 weeks was achieved in about one third of patients following a single application. The first part of this paper is a review of the pathophysiology, pharmacology, and published clinical trials with the capsaicin 8% cutaneous patch. The second part reports on outcomes of an interdisciplinary expert workshop, where new treatment results of three major German pain centers were presented and reviewed with the objectives of obtaining responder rates for different pain syndromes, assessing maintenance of effect under real-life conditions, and giving recommendations for practical care.

The 12 week responder rates with pain relief of ≥30% were comparable in patients with mononeuropathies (37.9%) and postherpetic neuralgia (38.8%). Similar responder rates were seen in a subgroup of patients with cervical spine radiculopathy and back pain (46.7%). In HIV-associated neuropathy the responder rates were high (47.8%) but lower in patients with other polyneuropathies (17.6%). Response rates were nearly identical after 1 week (46.6%) and 4 weeks (43.3) and dropped only slightly at 12 weeks (37.4%). In a subgroup of 54 patients who underwent a second treatment, efficacy was maintained. Response rates in patients with or without lidocaine pretreatment were comparable.

Treatment with the capsaicin 8% cutaneous patch was generally safe and well tolerated.

The workshop panel recommended further investigation of opportunities to improve the application procedure and to perform studies on the skin penetration and distribution of capsaicin. A modified quantitative sensory testing (QST) should be developed for clinical practice in order to better understand the correlation of sensory profiles and response to capsaicin treatment.

Keywords::

• Capsaicin
• Capsaicin 8% cutaneous patch
• Clinical experience
• Consensus workshop
• Peripheral neuropathic pain
• Responder rate

Transparency

Declaration of funding

The documentation of treatment results and the interdisciplinary workshop were funded by Astellas Pharma GmbH, Munich.

Declaration of financial/other relationships

R.-D.T. has been invited to this workshop by Astellas, he received research grants from Astellas, Boehringer Ingelheim, and Dr. Kade, has been an advisor for Acron Molecules, Pfizer, Grunenthal, Astellas, and DIMDI, and he has participated in the Speakers Bureau of Boehringer Ingelheim, Astellas, Mundipharma, and Grunenthal.

C.S. has received research grants from Genzyme, has been an advisor for UCB, Astellas, and Pfizer, and has participated in the Speakers Bureau of Allergan, Baxter, CSL Behring, Eli Lilly, Genzyme, and Pfizer.

G.A. has received research grants from Abbott and ViiV Healthcare and has received honoraria as consultant from Abbott, Astellas, BMS, Gilead, and ViiV. R.B. has received grants or research funding from Pfizer, Genzyme, Grünenthal, the German Federal Ministry of Education and Research (BMBF), the German Research Network on Neuropathic Pain, Modelling Pain Switches, and the German Research Foundation (DFG); has served as a member of the IMI ‘Europain’ collaboration (which includes the following industry members: AstraZeneca, Pfizer, Esteve, UCB-Pharma, Sanofi Aventis, Grünenthal, Eli Lilly, Neuroscience Technologies, and Boehringer Ingelheim); and has participated in speakers bureaus for Pfizer, Genzyme, Grünenthal, Mundipharma, Allergan, Sanofi Pasteur, Medtronic, Eisai, UCB BioSciences, Eli Lilly, Boehringer Ingelheim, Astellas, Novartis, and Bristol-Myers Squibb. F.B. has received sponsorships from Eli Lilly and research grants from Eli Lilly, Allergan, and Grünenthal; was a consultant for Eli Lilly, Pfizer, and Astellas; and has participated in speakers bureaus for Eli Lilly and Pfizer. T.C. has received sponsorships from Astellas and Mundipharma; was a consultant for Astellas and Esai; and has participated in speakers bureaus for Astellas, Medtronic, and Mundipharma. R.F. has received honoraria as consultant for Astellas, Eli Lilly, Forest Research, Grünenthal, HRA, and Pfizer and has participated in speakers bureaus for Astellas, Eli Lilly, Grunenthal, and Pfizer. H.-H.G. has received speaker’s honoraria from Eli Lilly, MSD, Mundipharma, and Pfizer. M.-L.H. is an employee of Astellas. I.W.H. has received sponsorship honoraria from Astra-Zeneca, BMS, Boehringer Ingelheim, GSK, Gilead, Grünenthal, MSD, and Pfizer. He has received a research grant from Gilead and participated in advisory boards for Astellas and Boehringer Ingelheim. K.-U.K. is a consultant for and/or received speaker fees from Astellas, Berlin Chemie, betapharm, Boehringer Ingelheim, Grünenthal, Mundipharma, Eli Lilly, medi Bayreuth, MSD, and Sharp & Dohme. A.L. has received honoraria for advising Astellas. S.S. has received a research grant from Astellas, and has participated in speakers bureaus for Eli Lilly and Pfizer. S.S. has received a research grant from Astellas. C.M. has received grants or research funding from Pfizer, the German Federal Ministry of Education and Research (BMBF), the German Research Network on Neuropathic Pain; has served as a member of the IMI ‘Europain’ collaboration (which includes the following industry members: AstraZeneca, Pfizer, Esteve, UCB-Pharma, Sanofi Aventis, Grünenthal, Eli Lilly, Neuroscience Technologies, and Boehringer Ingelheim); was a consultant for Mundipharma GmbH, MSD GmbH, Lilly GmbH, Grünenthal GmbH, Astellas GmbH, Sanofi; and has participated in Advisory Boards for Pfizer. T.W. has received sponsorships from Astellas, Grünenthal, Mundipharma, Pfizer, and Teva; in addition he received personal research grants from Astellas, Mundipharma, Pfizer, and Teva. R.J. has disclosed that he has received royalties from Grünenthal GmbH for advisory Board membership, and from Pfizer GmbH and Astellas GmbH for lectures. H.-H.N. has disclosed that he is a consultant to Astellas. G.W. has disclosed that he is on the speakers bureau for Astellas, Grünenthal, Mundipharma and Medtronic; he is a consultant to Grünenthal and Amgen and received grants from MHMRC. H.J. has disclosed that he is a consultant to Abbott. R.R. has disclosed that he is on the Scientific Advisory boards of Astellas, Pfizer, Grünenthal, and Eisai, and has received lecture fees from Astellas, Pfizer, Eli Lilly and Grünenthal.

Acknowledgments

Franz Gerstheimer (medwiss-extern GbR, Aachen) provided medical writing assistance funded by Astellas GmbH.