title: Pilot study of duloxetine for treatment of aromatase inhibitor-associated musculoskeletal symptoms.
abstract: BACKGROUND
  Approximately 50% of postmenopausal women with hormone receptor-positive early stage breast cancer treated with an aromatase inhibitor (AI) develop musculoskeletal symptoms. Standard analgesics are relatively ineffective. Duloxetine is a serotonin norepinephrine reuptake inhibitor with proven efficacy for treatment of multiple chronic pain states. The authors investigated the hypothesis that duloxetine is efficacious for treatment of AI-associated musculoskeletal symptoms.
  
  
  METHODS
  The authors performed a single-arm, open-label phase 2 study of duloxetine in postmenopausal women with breast cancer who developed new or worsening pain after treatment with an AI for at least 2 weeks. Patients were treated with duloxetine for 8 weeks (30 mg for 7 days, then 60 mg daily). The primary endpoint was a 30% decrease in average pain score over 8 weeks, and secondary outcomes included change in average and worst pain, pain interference, depression, sleep quality, and hot flashes. Statistical analysis was done with t tests for paired data.
  
  
  RESULTS
  Twenty-one of 29 evaluable patients (72.4%) achieved at least a 30% decrease in average pain, and 18 of 23 patients (78.3%) who completed protocol-directed treatment continued duloxetine. The mean percentage reduction in average pain severity between baseline and 8 weeks was 60.9% (95% confidence interval [CI], 48.6%-73.1%), and in maximum pain severity it was 59.9% (95% CI, 47.0-72.7%). The most common adverse events were grade 1 or 2 fatigue, xerostomia, nausea, and headache.
  
  
  CONCLUSIONS
  Duloxetine appears to be effective and well tolerated for treatment of AI-associated musculoskeletal symptoms. Future randomized, placebo-controlled studies are warranted.
authors.affiliation: Breast Oncology Program, University of Michigan Comprehensive Cancer Center, Ann Arbor, Michigan, USA.
authors.forename: N Lynn
authors.initials: NL
authors.lastname: Henry
authors.forename: Mousumi
authors.initials: M
authors.lastname: Banerjee
authors.forename: Max
authors.initials: M
authors.lastname: Wicha
authors.forename: Catherine
authors.initials: C
authors.lastname: Van Poznak
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Smerage
authors.forename: Anne F
authors.initials: AF
authors.lastname: Schott
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Griggs
authors.forename: Daniel F
authors.initials: DF
authors.lastname: Hayes
mesh_terms: D000328:Adult; D000368:Aged; D047072:Aromatase Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D059350:Chronic Pain; D000068736:Duloxetine Hydrochloride; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009140:Musculoskeletal Diseases / Q000139:chemically induced / Q000188:drug therapy* / Q000473:pathology; D010146:Pain / Q000139:chemically induced / Q000188:drug therapy*; D010865:Pilot Projects; D017698:Postmenopause; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use*; D013876:Thiophenes / Q000627:therapeutic use*
chemical_list: D047072:Aromatase Inhibitors; D000068736:Duloxetine Hydrochloride; D017367:Selective Serotonin Reuptake Inhibitors; D013876:Thiophenes