Objective: The uptake of new antipsychotic medications among children has not been studied adequately. Although ziprasidone received Food and Drug Administration approval for the treatment of psychotic disorders among children in June 2009, it first became available for off-label use by children in 2001 and presented an excellent case study for off-label market entry. The objective of this study was to determine the pattern of initiation and switching for off-label use of ziprasidone among Michigan children who were insured by Medicaid in the first year that ziprasidone was available.
Methods: We conducted a retrospective study by using Michigan Medicaid data for patients who were aged <21 years and had 2 years of continuous enrollment and at least 1 prescription for ziprasidone in the first year the medication was available. The main outcome measures were proportion of children prescribed ziprasidone as their first antipsychotic, with evidence of treatment resistance, and by a psychiatrist.
Results: In the first year, 292 individuals who met criteria were prescribed ziprasidone. Approximately 53% had a diagnosis of psychosis. Explosive personality disorder and oppositional defiant disorder were the next most common diagnoses. For 33% of individuals, this was the first antipsychotic medication. Only 12% of individuals showed evidence of treatment resistance to other antipsychotic medications before switching to ziprasidone.
Conclusions: During the period when ziprasidone had no approved pediatric usages, a small percentage of patients who were prescribed ziprasidone showed evidence of treatment resistance, the primary expected indication. Some prescribing for ziprasidone in the first year in this population could be considered inappropriate considering what was known about the safety and efficacy of ziprasidone in children and adolescents at the time. "Fail first" and prior authorization policies may be appropriate in the first year a medication is available so as to protect children from potential serious harm.