Neuropathic Pain
Current Pharmacological Treatments of Neuropathic Pain and Unmet Needs
High-Dose Capsaicin
Mechanism of Action
Dose and Administration, and Benefits of Localized Rather Than Systemic Analgesia
Clinical Trial Data That Led to its Launch, Including the Recent EC Approval for Expanded Treatment Options
References | Study design | Diagnosis | N verum/N placebo | Treatment | Outcome | Percentage of adverse events | |
---|---|---|---|---|---|---|---|
[29] | Multicenter, double-blind, randomized, controlled | Postherpetic neuralgia | 206/196 | One 60-min application of 640 μg/cm2 capsaicin 8% patch | One 60-min application of 3.2 μg/cm2 capsaicin 0.04% patch | ≥30% reduction in pain intensity of 42% in verum versus 32% in control group Mean change in numeric pain rating scale score: −29.6% in verum versus −19.9% in control group | Verum: 99%, control: 88%; any adverse event |
[31] | Multicenter, double-blind, randomized, controlled (conformational study) | Postherpetic neuralgia | 194/186 | One 60-min application of 640 μg/cm2 capsaicin 8% patch | One 60-min application of 3.2 μg/cm2 capsaicin 0.04% patch | ≥30% reduction in pain intensity of 46% in verum versus 34% in control group 32.0% mean reduction from baseline in pain in verum versus 24.4% in control group | Verum: 98%, control: 87%; any adverse event |
[30] | Randomized, double-blind, controlled study (with open-label extension) | Postherpetic neuralgia | 32/12 Open-label extension: 15/7 | One 60-min application of 640 μg/cm2 capsaicin 8% patch | One 60-min application of 3.2 μg/cm2 capsaicin 0.04% patch | Mean change in numeric pain rating scale score: −32.7% in verum versus −4.4% in control group | Verum: 42%, control: 17%; any adverse event |
[32] | Multicenter, double-blind, randomized, controlled (dose finding) | Postherpetic neuralgia | 200/73 | One 30, 60 or 90-min application of 640 μg/cm2 capsaicin 8% patch | One 30, 60 or 90-min application of 3.2 μg/cm2 capsaicin 0.04% patch | Mean percent reductions in numeric pain ratings from baseline were 26.5% in total verum versus 17.3% in the pooled control group 60-min treatment with mean percent reduction in average pain scores of 28% | Verum: 59%, control: 56%; ≥1 adverse event |
[34] | Multicenter, double-blind, randomized, controlled | Painful HIV-associated neuropathy | 225/82 | One 30, 60 or 90-min application of 640 μg/cm2 capsaicin 8% patch | One 30, 60 or 90-min application of 3.2 μg/cm2 capsaicin 0.04% patch | ≥30% reduction in pain intensity of 33% in verum versus 18% in control group Reduction in pain ratings in 23% of patients on verum versus 11% of patients on control Mean pain reductions in 30-, 60- and 90-min groups: 27.7, 15.9, and 24.7% | Verum: 72%, control: 55%; any adverse event |
[33] | Double-blind, randomized, controlled | Painful HIV-associated neuropathy | 332/162 | One 30 or 60-min application of 640 μg/cm2 capsaicin 8% patch | One 30 or 60-min application of 3.2 μg/cm2 capsaicin 0.04% patch | Pain reduction not different between total groups (−29.5% verum versus −24.5% control) Pain reduction not different between 30-min groups (−26.2% verum versus −19.1% control) Pain reduction not different between 60-min groups (−32.8% verum versus −30% control) | Verum: 93%, control: 83%; ≥1 adverse event |