title: Economic impact of therapeutic substitution of a brand selective serotonin reuptake inhibitor with an alternative generic selective serotonin reuptake inhibitor in patients with major depressive disorder.
abstract: BACKGROUND
  To reduce pharmacy costs, managed care organizations encourage therapeutic substitution from brand to a generic product. However, little is known about whether these cost-containment strategies can also potentially lower total expenditures for payers in treatment of major depressive disorder (MDD).
  
  
  OBJECTIVE
  To compare economic outcomes of patients with MDD who were switched from a brand selective serotonin reuptake inhibitor (SSRI) to an alternative generic SSRI for nonmedical reasons versus patients who continued on the brand SSRI.
  
  
  METHODS
  Adult MDD patients in the Ingenix Impact Database (2003-2007) were considered "switchers" if they received treatment with a brand SSRI and were later switched to an alternative generic SSRI for nonmedical reasons. Patients who remained on the brand SSRI (nonswitchers) were matched 1:1 with switchers. All-cause, mental health-related, and MDD-related rates of hospitalizations/emergency department (ED) visits and costs over 6 months were compared both descriptively and by using adjusted regression models. A subgroup analysis on patients who were switched from escitalopram (Lexapro) to an alternative generic SSRI was also performed.
  
  
  RESULTS
  The study included 4449 matched pairs. Compared with nonswitchers, switchers had higher risk of all-cause, mental health-related, and MDD-related use of hospitalizations/ED visits (OR 1.15, 1.34, and 1.54, respectively; all p < 0.01) and higher risk-adjusted mental health-related and MDD-related medical costs ($219 and $222, respectively; both p < 0.05). Subgroup analysis on escitalopram showed similar results; switchers experienced higher risk of any-cause, mental health-related, and MDD-related use of hospitalizations/ED visits (OR 1.21, 1.41, and 1.53, respectively; all p < 0.01) and higher risk-adjusted MDD-related medical costs ($151; p < 0.05).
  
  
  CONCLUSIONS
  Compared with patients who continued on their patented SSRIs, patients who switched to a generic SSRI incurred more resource use of hospitalizations/ED visits and higher MDD-related health-care costs. The effects of therapeutic substitution should be carefully examined, because use of generic alternatives may not be a cost-saving strategy when total health-care costs are considered.
authors.affiliation: Analysis Group Inc., Boston, MA, USA. ewu@analysisgroup.com
authors.forename: Eric Q
authors.initials: EQ
authors.lastname: Wu
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Yu
authors.forename: Veronique
authors.initials: V
authors.lastname: Lauzon
authors.forename: Karthik
authors.initials: K
authors.lastname: Ramakrishnan
authors.forename: Maryna
authors.initials: M
authors.lastname: Marynchenko
authors.forename: Rym
authors.initials: R
authors.lastname: Ben-Hamadi
authors.forename: Steven
authors.initials: S
authors.lastname: Blum
authors.forename: M Haim
authors.initials: MH
authors.lastname: Erder
mesh_terms: D000328:Adult; D000928:Antidepressive Agents / Q000191:economics / Q000627:therapeutic use; D015283:Citalopram / Q000191:economics / Q000627:therapeutic use; D003362:Cost-Benefit Analysis; D003865:Major Depressive Disorder / Q000188:drug therapy* / Q000191:economics*; D057915:Drug Substitution / Q000191:economics*; D016568:Drugs, Generic / Q000191:economics* / Q000627:therapeutic use*; D004636:Emergency Service, Hospital / Q000191:economics; D005260:Female; D017048:Health Care Costs; D006760:Hospitalization / Q000191:economics; D006801:Humans; D008297:Male; D017367:Selective Serotonin Reuptake Inhibitors / Q000191:economics* / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000928:Antidepressive Agents; D015283:Citalopram; D016568:Drugs, Generic; D017367:Selective Serotonin Reuptake Inhibitors