title: Qutenza (capsaicin) 8% patch onset and duration of response and effects of multiple treatments in neuropathic pain patients.
abstract: BACKGROUND
  Qutenza (capsaicin) 8% patch is used to treat various neuropathic indications, including postherpetic neuralgia (PHN) and human immunodeficiency virus-associated neuropathy (HIV-AN).
  
  
  OBJECTIVE
  We conducted a meta-analysis of Qutenza studies to describe clinical phenomena of effects of Qutenza treatment better, such as onset and duration of pain relief, and the need for retreatments.
  
  
  METHODS
  The meta-analyses combined individual patient data (1313 participants with PHN and 801 with HIV-AN) from 7 completed randomized, double-blind, controlled studies. Studies had similar designs, and all used the Qutenza patch (8% capsaicin) and a low-dose control patch (0.04% capsaicin). A 30% response was defined as a ≥30% decrease in mean pain intensity score during week 2 to end of follow-up; complete pain relief was defined as an average pain intensity ≤1 during week 2 to end of follow-up. Duration of response was calculated using the data from long-term studies as the time from onset of response to offset of response, retreatment, or end of follow-up (whichever occurred first).
  
  
  RESULTS
  Overall 44% of PHN and 41% of HIV-AN patients had a 30% response, and 11% and 7%, respectively, had complete pain relief 2 to 12 weeks after treatment with Qutenza. The mean (median) onset of response to Qutenza was 3.4 (1) days for PHN and 6.5 (4) days for HIV-AN (delayed due to an initial increase in discomfort). The mean (median) duration of response after 1 Qutenza treatment was 5 (3) months. Of the patients followed-up for 12 months, 40% PHN and 36% HIV-AN patients had a 30% response, and 9% and 10%, respectively, had complete pain relief from week 2 to end of follow-up.
  
  
  CONCLUSIONS
  Qutenza is effective in a high proportion of patients. In patients who respond to Qutenza, analgesia starts within a few days of treatment and lasts on average 5 months.
authors.affiliation: *Analgesic Solutions, Natick ‡LLX Solutions, Watertown §Biobridges, Wellesley, MA †FocusBiocom, Durango, CO ∥Astellas Pharma Global Development, Leiderdorp, The Netherlands.
authors.forename: Joy
authors.initials: J
authors.lastname: Mou
authors.forename: Florence
authors.initials: F
authors.lastname: Paillard
authors.forename: Barry
authors.initials: B
authors.lastname: Turnbull
authors.forename: Jeremiah
authors.initials: J
authors.lastname: Trudeau
authors.forename: Malcolm
authors.initials: M
authors.lastname: Stoker
authors.forename: Nathaniel P
authors.initials: NP
authors.lastname: Katz
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002211:Capsaicin / Q000008:administration & dosage*; D016208:Databases, Factual / Q000706:statistics & numerical data; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000150:complications; D006801:Humans; D008297:Male; D008875:Middle Aged; D051474:Neuralgia, Postherpetic / Q000188:drug therapy*; D010146:Pain / Q000188:drug therapy* / Q000209:etiology / Q000821:virology; D010147:Pain Measurement; D016032:Randomized Controlled Trials as Topic; D018689:Sensory System Agents / Q000008:administration & dosage*; D013997:Time Factors; D057968:Transdermal Patch; D055815:Young Adult
chemical_list: D018689:Sensory System Agents; D002211:Capsaicin