Summary of the comparative effectiveness review on off-label use of atypical antipsychotics

Abstract

Background: Conventional and atypical antipsychotic medications are approved by the FDA for treatment of schizophrenia and bipolar disorder. Over many decades, the widespread use of conventional antipsychotics produced various side effects requiring additional medications, such as the atypical antipsychotics. Beginning in 2006, 9 atypical antipsychotic drugs have been approved by the FDA for indications that were previously off-label uses: aripiprazole (as augmentation for major depressive disorder [MDD] and for autism spectrum disorders), asenapine, clozapine, iloperidone, olanzapine (in combination with fluoxetine for MDD and bipolar depression), paliperidone, quetiapine (quetiapine and quetiapine XR [extended release] as monotherapy in bipolar depression and quetiapine XR as augmentation for MDD), risperidone (for autism spectrum disorders), and ziprasidone. In 2006, the Agency for Healthcare Research and Quality (AHRQ) published a systematic review on the comparative effectiveness of off-label uses of atypical antipsychotics. Since that time, numerous studies have been published evaluating these therapies in various new off-label uses; new or increased adverse effects have been observed with off-label uses; new atypical antipsychotics have been approved; and previously off-label uses have been approved for some atypical antipsychotics. Hence, AHRQ published an updated review in September 2011 that summarized the benefits and harms of atypical antipsychotics in the treatment of attention-deficit hyperactivity disorder/attention deficit disorder (ADHD), anxiety, behavioral disturbances of dementia and severe geriatric agitation, depression, eating disorders, insomnia, obsessive-compulsive disorder (OCD), personality disorder, post-traumatic stress disorder (PTSD), substance use and dependence disorders, and Tourette's syndrome. The new report also investigated topics for which data in the previous report were found to be insufficient to make conclusions, including subpopulations (i.e., race/ethnicity, gender) that would benefit most from atypical antipsychotics, appropriate dose, and time needed to see clinical improvement. The 2011 review included the following atypical antipsychotics: aripiprazole, olanzapine, quetiapine, risperidone, and ziprasidone; no clinical trials were found for off-label use of the 3 most recently FDA-approved atypical antipsychotics (asenapine, iloperidone, and paliperidone).

Objectives: To (a) familiarize health care professionals with the methods and findings from AHRQ's 2011 Comparative Effectiveness Review (CER) of off-label use of atypical antipsychotics, (b) encourage consideration of the clinical and managed care applications of the review findings, and (c) identify limitations and gaps in the existing research with respect to the benefits and risks of off-label use of atypical antipsychotics.

Summary: Antipsychotic medications are FDA approved for the treatment of schizophrenia and bipolar disorder. Conventional antipsychotics have been widely used for decades and spurred the development of the atypical antipsychotics. Atypical antipsychotics were produced and are now being used for patients who may have experienced various side effects while using conventional antipsychotics.In 2006, an AHRQ study reviewed off-label uses of atypical antipsychotics (excluding clozapine because of its association with potentially fatal bone marrow suppression and the requirement for frequent blood tests for safety monitoring). Findings indicated that the most common off-label uses of these drugs included depression, OCD, PTSD, personality disorders, Tourette's syndrome, autism, and agitation in dementia. The reviewers concluded in 2006 that overall there was not sufficiently high strength of evidence of efficacy for any off-label use of atypical antipsychotics. There was, however, strong evidence for an increased risk of adverse events with off-label use, including significant weight gain and sedation and increased mortality among the elderly.Since the 2006 review, significant developments occurred in the use of atypical antipsychotics, including FDA approval of the atypical antipsychotics asenapine, iloperidone, and paliperidone and FDA approval of previous off-label uses: (a) quetiapine and quetiapine XR as monotherapy in bipolar depression; (b) quetiapine XR as augmentation therapy for MDD; (c) aripiprazole as augmentation therapy for MDD; (d) olanzapine/fluoxetine combination for MDD; (e) olanzapine/fluoxetine combination for bipolar depression; and (f) risperidone and aripiprazole for autism spectrum disorders. Additional studies have been published for new off-label uses, and there have been reports of new or increased adverse effects for off-label uses.Further review of previously insufficient information was warranted on subpopulations where treatment modification such as dosing may increase efficacy. The 2006 review did not have sufficient information to make conclusions regarding subpopulations (i.e., race/ethnicity, gender) that would benefit most from atypical antipsychotics, appropriate dosing, and the duration of treatment needed to see clinical improvement. The updated AHRQ report in 2011 reviewed off-label uses of atypical antipsychotic medications in anxiety, ADHD, behavioral disturbances of dementia and severe geriatric agitation, MDD, eating disorders, insomnia, OCD, PTSD, personality disorders, substance abuse, and Tourette's syndrome; autism was included in the 2006 review but is now reviewed in a separate report of the comparative effectiveness of antipsychotics for on-label uses. The significant findings in the updated review include (a) small but statistically significant benefits for olanzapine, aripiprazole, and risperidone for elderly patients with dementia; (b) quetiapine appears superior to placebo for general anxiety disorder (GAD); (c) risperidone was associated with benefits in the treatment of OCD; and (d) adverse events are common. Atypical antipsychotics were not effective in the treatment of eating disorders or personality disorder. The evidence did not support the use of atypical antipsychotics in the treatment of substance abuse, and data were inconclusive for the use of these medications for insomnia. The number needed to harm (NNH) was calculated for adverse events in elderly patients, including risk of death (NNH = 87), stroke (NNH = 53 for risperidone), extrapyramidal symptoms (NNH = 10 for olanzapine and NNH = 20 for risperidone), and urinary symptoms (NNH = 16 to 36). Adverse events in nonelderly adults included weight gain (particularly with olanzapine), fatigue, sedation, akathisia (with aripiprazole), and extrapyramidal symptoms.