Pain response profile of patients with fibromyalgia treated with duloxetine.
OBJECTIVE
This study examined the time course for minimal clinically significant improvement in pain severity during the initial 12 weeks of treatment in patients with fibromyalgia taking duloxetine.


METHODS
Four double-blind, placebo-controlled trials of duloxetine were pooled. Patients received duloxetine 60 mg/d, 120 mg/d, or placebo. Clinically significant treatment response (>or=30% reduction in pain severity on the 24-hour average pain severity of the Brief Pain Inventory scale) was assessed over 12 weeks.


RESULTS
At endpoint, 46.9% of duloxetine 60-mg-, 48.6% of duloxetine 120-mg-, and 32.1% of placebo-treated patients (P<0.001 for both doses) had >or=30% improvement on average pain from baseline. The probabilities of achieving >or=30% response at Weeks 1, 2, 4, 8, and 12 among duloxetine 60-mg-treated patients were 27%, 44%, 45%, 47%, and 49%, respectively, and among duloxetine 120-mg-treated patients were 35%, 43%, 53%, 53%, and 51%, respectively (P<0.01 vs. placebo at each week, for both doses). Among patients who did not respond by Weeks 1, 2, 4, and 8, the percentages of duloxetine 60-mg-treated patients who achieved a response by the endpoint of the study were 36.9%, 29.8%, 28.9%, and 26.9%, respectively.


CONCLUSIONS
This article examines the time course for minimal clinically significant improvement in pain severity in duloxetine-treated patients with fibromyalgia. It provides information about continued treatment in patients who do not initially respond to duloxetine. This information could potentially help physicians facing clinical decisions about management of fibromyalgia with duloxetine.
Bradley
Laurence A
LA
University of Alabama at Birmingham, Birmingham, AL, USA.
Wohlreich
Madelaine M
MM
Wang
Fujun
F
Gaynor
Paula J
PJ
Robinson
Michael J
MJ
D'Souza
Deborah N
DN
Mease
Philip J
PJ
D018759:Adrenergic Uptake Inhibitors / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D000068736:Duloxetine Hydrochloride; D005260:Female; D005356:Fibromyalgia / Q000150:complications* / Q000188:drug therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000188:drug therapy* / Q000209:etiology*; D010147:Pain Measurement / Q000379:methods; D013876:Thiophenes / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
D018759:Adrenergic Uptake Inhibitors; D013876:Thiophenes; D000068736:Duloxetine Hydrochloride