title: Early response predicts subsequent response to olanzapine long-acting injection in a randomized, double-blind clinical trial of treatment for schizophrenia.
abstract: BACKGROUND
  In patients with schizophrenia, early non-response to oral antipsychotic therapy robustly predicts subsequent non-response to continued treatment with the same medication. This study assessed whether early response predicted later response when using a long-acting injection (LAI) antipsychotic.
  
  
  METHODS
  Data were taken from an 8-week, randomized, double-blind, placebo-controlled study of olanzapine LAI in acutely ill patients with schizophrenia (n = 233). Early response was defined as ≥ 30% improvement from baseline to Week 4 in Positive and Negative Syndrome Scale (PANSS0-6) Total score. Subsequent response was defined as ≥ 40% baseline-to-endpoint improvement in PANSS0-6 Total score. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and predictive accuracy were calculated. Clinical and functional outcomes were compared between Early Responders and Early Non-responders.
  
  
  RESULTS
  Early response/non-response to olanzapine LAI predicted later response/non-response with high sensitivity (85%), specificity (72%), PPV (78%), NPV (80%), and overall accuracy (79%). Compared to Early Non-responders, Early Responders had significantly greater improvement in PANSS0-6 Total scores at all time points and greater baseline-to-endpoint improvement in PANSS subscale scores, Quality of Life Scale scores, and Short Form-36 Health Survey scores (all p ≤ .01). Among Early Non-responders, 20% demonstrated response by Week 8. Patients who lacked early improvement (at Week 4) in Negative Symptoms and Disorganized Thoughts were more likely to continue being non-responders at Week 8.
  
  
  CONCLUSIONS
  Among acutely ill patients with schizophrenia, early response predicted subsequent response to olanzapine LAI. Early Responders experienced significantly better clinical and functional outcomes than Early Non-responders. Findings are consistent with previous research on oral antipsychotics.
  
  
  BACKGROUND
  F1D-MC-HGJZ: Comparison of Intramuscular Olanzapine Depot With Placebo in the Treatment of Patients With Schizophrenia http://clinicaltrials.gov/ct2/show/NCT00088478?term=olanzapine+depot&rank=3Registry identifier - NCT00088478.
authors.affiliation: Global Health Outcomes, Eli Lilly and Company, USA.
authors.forename: Haya
authors.initials: H
authors.lastname: Ascher-Svanum
authors.forename: Fangyi
authors.initials: F
authors.lastname: Zhao
authors.forename: Holland C
authors.initials: HC
authors.lastname: Detke
authors.forename: Allen W
authors.initials: AW
authors.lastname: Nyhuis
authors.forename: Anthony H
authors.initials: AH
authors.lastname: Lawson
authors.forename: Virginia L
authors.initials: VL
authors.lastname: Stauffer
authors.forename: William
authors.initials: W
authors.lastname: Montgomery
authors.forename: Michael M
authors.initials: MM
authors.lastname: Witte
authors.forename: David P
authors.initials: DP
authors.lastname: McDonnell
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000627:therapeutic use; D001569:Benzodiazepines / Q000008:administration & dosage / Q000627:therapeutic use*; D003692:Delayed-Action Preparations / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007273:Injections, Intramuscular; D008297:Male; D008875:Middle Aged; D000077152:Olanzapine; D011237:Predictive Value of Tests; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D012559:Schizophrenia / Q000188:drug therapy*; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D014150:Antipsychotic Agents; D003692:Delayed-Action Preparations; D001569:Benzodiazepines; D000077152:Olanzapine