title: Long-term efficacy and tolerability of clozapine combined with ziprasidone or risperidone.
abstract: BACKGROUND
  Treatment resistance in schizophrenia often leads to add-on of atypical antipsychotics to clozapine.
  
  
  METHODS
  In a randomized trial, we recently obtained evidence for comparable efficacy and differential side effects of clozapine in combination with ziprasidone (CZ, N=12) versus risperidone (CR, N=12). Here, we present the open-label, long-term evaluations of these patients after 26 and 52 weeks.
  
  
  RESULTS
  Sustained improvements of psychopathology as assessed by PANSS (positive and negative syndrome scale), SANS (scale for the assessment of negative symptoms), and HAMD (Hamilton depression scale) were documented in both subsamples being treated according to protocol, while dropouts reduced the study sample after 26 (CZ: reduced by -4; CR: -2) and 52 weeks (CZ: -0; CR: -5). We observed a slight increase of akathisia in the CZ group whereas general clozapine-associated side effects improved.
  
  
  CONCLUSIONS
  The combinations of clozapine with ziprasidone or risperidone exhibit long-term efficacy, but the level of evidence is limited. Further head-to-head comparisons of atypical antipsychotics as add-on to clozapine are necessary.
authors.affiliation: Central Institute of Mental Health, Department of Psychiatry and Psychotherapy, University of Heidelberg, Mannheim, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Kuwilsky
authors.forename: B
authors.initials: B
authors.lastname: Krumm
authors.forename: S
authors.initials: S
authors.lastname: Englisch
authors.forename: H
authors.initials: H
authors.lastname: Dressing
authors.forename: M
authors.initials: M
authors.lastname: Zink
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D003024:Clozapine / Q000009:adverse effects / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004351:Drug Resistance; D004359:Drug Therapy, Combination; D006801:Humans; D008875:Middle Aged; D010879:Piperazines / Q000009:adverse effects / Q000627:therapeutic use*; D011569:Psychiatric Status Rating Scales; D018967:Risperidone / Q000009:adverse effects / Q000627:therapeutic use*; D012702:Serotonin Antagonists / Q000009:adverse effects / Q000627:therapeutic use*; D013844:Thiazoles / Q000009:adverse effects / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents; D010879:Piperazines; D012702:Serotonin Antagonists; D013844:Thiazoles; C092292:ziprasidone; D003024:Clozapine; D018967:Risperidone