title: Results of switching to milnacipran in fibromyalgia patients with an inadequate response to duloxetine: a phase IV pilot study.
abstract: BACKGROUND
  The purpose of this study was to evaluate the safety, tolerability, and efficacy of milnacipran following a direct switch from duloxetine in fibromyalgia patients experiencing inadequate clinical response to duloxetine after receiving treatment for 6 weeks or longer.
  
  
  METHODS
  This exploratory study included 107 patients with fibromyalgia who had been treated with duloxetine 60 mg/day for at least 4 weeks prior to enrollment. Following a 2-week open-label period on duloxetine, patients who had visual analog scale pain scores ≥ 40 and were dissatisfied with current treatment were randomized 4:1 to milnacipran 100 mg/day (n = 86) or placebo (n = 21) for 10 weeks of double-blind treatment. The small placebo group was included solely to blind the study and minimize expectation bias among patients and investigators, and there was no preplanned statistical comparison between treatment groups. The primary efficacy parameter was the percentage of patients rating themselves as "much improved" or "very much improved" on the Patient Global Impression of Change (PGIC) at the final visit. Other efficacy parameters included changes in one-week recall visual analog scale pain, Fibromyalgia Impact Questionnaire Revised (FIQR), and Multiple Ability Self-Report Questionnaire (MASQ).
  
  
  RESULTS
  Of patients switched to milnacipran, 32.9% were classified as PGIC responders, and they also demonstrated improvement in visual analog scale pain, FIQR total, and MASQ total scores (mean changes from baseline were -12.3, -7.77, and -2.39, respectively). Nausea and dizziness were the most common treatment-emergent adverse events in patients switched to milnacipran, reported in 21% and 15%, respectively, of patients in this group.
  
  
  CONCLUSIONS
  Results from this exploratory study suggest that switching from duloxetine to milnacipran may be beneficial in some patients with fibromyalgia who have an inadequate response to duloxetine. Further research investigating the efficacy and safety of switching fibromyalgia therapies is warranted.
authors: Fatigue Consultation Clinic, Salt Lake City, UT.
authors: Lucinda
authors: L
authors: Bateman
authors: Robert H
authors: RH
authors: Palmer
authors: Joel M
authors: JM
authors: Trugman
authors: Yuhua
authors: Y
authors: Lin
keywords: duloxetine; fibromyalgia; milnacipran; switch
references: Arch Gen Psychiatry. 1961 Jun;4:561-71
references: 13688369
references: Clin Rheumatol. 2011 May;30(5):655-64
references: 21057839
references: Rheum Dis Clin North Am. 2009 May;35(2):215-32
references: 19647138
references: Arch Gen Psychiatry. 2002 Mar;59(3):233-9
references: 11879161
references: Biol Psychiatry. 2004 Feb 1;55(3):320-2
references: 14744476
references: J Clin Exp Neuropsychol. 1994 Feb;16(1):93-104
references: 8150893
references: J Clin Psychiatry. 2008 Jan;69(1):95-105
references: 18312043
references: Arthritis Care Res (Hoboken). 2010 May;62(5):600-10
references: 20461783
references: Curr Med Res Opin. 2011 Mar;27(3):673-83
references: 21294700
references: J Manag Care Pharm. 2012 Jul-Aug;18(6):415-26
references: 22839682
references: Nat Rev Rheumatol. 2010 Aug;6(8):439-40
references: 20676122
references: Mayo Clin Proc. 2012 May;87(5):488-96
references: 22560527
references: Patient Educ Couns. 2008 Oct;73(1):114-20
references: 18640807
references: Clin J Pain. 2010 May;26(4):284-90
references: 20393262
references: Appl Health Econ Health Policy. 2011 Mar 1;9(2):125-36
references: 21332254
references: J Clin Psychiatry. 2004 Jan;65(1):37-43
references: 14744166
references: J Sex Marital Ther. 2000 Jan-Mar;26(1):25-40
references: 10693114
references: J Rheumatol. 2011 Jun;38(6):1113-22
references: 21285161
references: BMC Health Serv Res. 2010 Apr 26;10:102
references: 20420681
references: Clin Rheumatol. 2012 Feb;31(2):347-55
references: 21979445
references: Clin Exp Rheumatol. 2009 Sep-Oct;27(5 Suppl 56):S67-74
references: 20074443
references: Arthritis Rheum. 1995 Jan;38(1):19-28
references: 7818567
references: J Psychiatr Pract. 2007 Mar;13(2):97-105
references: 17414685
references: Med Care. 2005 Nov;43(11):1078-86
references: 16224300
references: Arthritis Rheum. 2005 Aug 15;53(4):519-27
references: 16082646