High-concentration capsaicin in HIV-associated neuropathy: Clinical evidence and cases

HIV-associated neuropathy (HIV-AN) occurs frequently in patients with HIV infection or AIDS, but it is one of the more difficult forms of peripheral neuropathic pain to treat effectively. Results of two randomized, double-blind trials indicated that a 30-minute application of a high-concentration capsaicin (8% w/w) patch (NGX-4010; QUTENZA™) is the optimal dosage to alleviate pain associated with HIV-AN. A subsequent integrated efficacy analysis of the two trials revealed that a 30-minute application of the high-concentration capsaicin patch produced significantly greater pain relief than a low-concentration capsaicin (0.04% w/w) control patch (mean reduction in Numeric Pain Rating Scale score from baseline to Weeks 2-12; −27.0% vs −15.7%; p = 0.003). After application of the high-concentration capsaicin patch, significant pain reduction was apparent by Week 2 and this was maintained throughout the 12-week assessment period. In addition, significantly more patients responded to the high-concentration capsaicin patch than to control across other endpoints measured. Pain relief was evident regardless of concomitant pain medication and antiretroviral therapy. As the high-concentration capsaicin patch was also well tolerated, with only transient, localized application site-related reactions, these clinical data indicate that the high-concentration capsaicin patch could provide a promising new treatment for painful HIV-AN.