title: Clinical outcomes following switch from venlafaxine ER to desvenlafaxine in nonresponders and responders.
abstract: OBJECTIVE
  This post hoc analysis examined efficacy and tolerability of open-label desvenlafaxine in patients with major depressive disorder switched from blinded placebo, venlafaxine extended release (ER), or desvenlafaxine.
  
  
  METHODS
  Patients who completed 8 weeks of double-blind therapy with placebo (n = 176), venlafaxine ER (n = 175), or desvenlafaxine (n = 143) enrolled in a 10-month, open-label extension study and received desvenlafaxine 200 to 400 mg/d. Efficacy (17-item Hamilton Depression Rating Scale [HDRS(17)]) was assessed separately for nonresponders and responders to double-blind treatment. Tolerability during the first month of open-label desvenlafaxine was assessed.
  
  
  RESULTS
  Among nonresponders (n = 134) to double-blind placebo, venlafaxine ER, and desvenlafaxine, mean decreases in HDRS(17) scores were -10.9, -7.3, and -7.7, respectively; HDRS(17) response rates were 67%, 53%, and 48%, respectively. Although responders (n = 360) to double-blind placebo, venlafaxine ER, and desvenlafaxine had more modest decreases on the HDRS(17), response rates were higher (84%, 87%, and 83%, respectively). Rates of adverse events were highest during week 1, and decreased afterward for the remainder of the first month of treatment.
  
  
  CONCLUSIONS
  Among nonresponders to 8 weeks of double-blind venlafaxine ER, desvenlafaxine, or placebo, 48% to 67% subsequently responded to open-label desvenlafaxine. Over 80% of responders to double-blind therapy maintained response on open-label desvenlafaxine. The switch from venlafaxine ER to desvenlafaxine was well tolerated.
authors.affiliation: Pfizer Inc., Collegeville, PA, USA. christine.guico-pabia@pfizer.com
authors.forename: C J
authors.initials: CJ
authors.lastname: Guico-Pabia
authors.forename: Q
authors.initials: Q
authors.lastname: Jiang
authors.forename: P T
authors.initials: PT
authors.lastname: Ninan
authors.forename: M E
authors.initials: ME
authors.lastname: Thase
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000465:Algorithms; D003511:Cyclohexanols / Q000008:administration & dosage* / Q000009:adverse effects; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000009:adverse effects; D003865:Major Depressive Disorder / Q000188:drug therapy*; D000069468:Desvenlafaxine Succinate; D004311:Double-Blind Method; D004351:Drug Resistance / Q000187:drug effects; D057915:Drug Substitution; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010919:Placebos; D016896:Treatment Outcome; D000069470:Venlafaxine Hydrochloride; D055815:Young Adult
chemical_list: D003511:Cyclohexanols; D003692:Delayed-Action Preparations; D010919:Placebos; D000069470:Venlafaxine Hydrochloride; D000069468:Desvenlafaxine Succinate