Risperidone (Risperdal - Janssen), a benzisoxazole derivative, is now available in the USA for treatment of schizophrenia and other psychotic disorders.

Three extended-release injectable formulations of second-generation antipsychotic drugs — two of risperidone (Rykindo, Uzedy) and one of aripiprazole (Abilify Asimtufii) — have been approved by the FDA for treatment of schizophrenia in adults. Rykindo and Abilify Asimtufii are also approved for maintenance treatment of bipolar I disorder in adults. Other extended-release injectable formulations of risperidone and aripiprazole have been available in the US for years (see Table 1).

A recent supplement to the Journal of Clinical Psychiatry, titled "The Expert Consensus Guideline Series: Optimizing Pharmacologic Treatment of Psychotic Disorders," concluded that most experts endorsed use of second-generation (atypical) antipsychotics rather than first-generation drugs, with risperidone (Risperdal - Janssen) the top choice for first episodes, multiple episodes or switches from another drug (JM Kane et al, J Clin Psychiatry 2003; 64 suppl 12:5). The supplement was sponsored by Janssen.

Augmentation with a second-generation (atypical) antipsychotic is a treatment option for patients with major depressive disorder (MDD) whose symptoms persist following antidepressant monotherapy. Aripiprazole (Abilify), olanzapine in a fixed-dose combination with fluoxetine (Symbyax), and extended-release quetiapine (Seroquel XR) have been approved by the FDA for such use.

Paliperidone (Invega - Janssen) has been approved by the FDA in an extended-release formulation for treatment of schizophrenia. It is the primary active metabolite of the second-generation antipsychotic risperidone (Risperdal - Janssen), which is scheduled to lose its patent exclusivity in December 2007.

The FDA has reported that 5106 elderly patients with dementia treated with atypical (second generation) antipsychotics in 17 randomized controlled trials had a higher mortality rate (4.5% vs. 2.6%) than those receiving placebo. Most of the deaths were due to cardiovascular and infectious causes (such as pneumonia). The drugs used in the trials were aripiprazole (Abilify), olanzapine (Zyprexa), quetiapine (Seroquel), and risperidone (Risperdal). As the increase in mortality was considered a class effect, the FDA advisory also included ziprasidone (Geodon), clozapine (Clozaril) and the...

Olanzapine (Zyprexa - Lilly), a thienobenzodiazepine that structurally resembles and binds to many of the same receptors as clozapine (Clozaril), is now available in the USA for treatment of schizophrenia and other psychotic disorders.

Quetiapine (Seroquel - Zeneca), a dibenzothiazepine derivative, has been approved by the FDA for treatment of schizophrenia and other psychotic disorders. It is a new addition to the 'atypical' antipsychotics, which include olanzapine (Zyprexa - Medical Letter, 39:5, 1997), risperidone (Risperdal) and clozapine (Clozaril). Atypical antipsychotic drugs generally are less likely to cause extrapyramidal symptoms than older drugs such as haloperidol (Haldol, and others) or the phenothiazines.

The FDA has approved lumateperone (Caplyta — Intracellular Therapies), an oral second-generation antipsychotic, for once-daily treatment of schizophrenia in adults. It is the 13th second-generation antipsychotic drug to be approved by the FDA for this indication.

Ziprasidone (Geodon - Pfizer), a benzisothiazolyl piperazine, has been approved by the FDA for oral treatment of schizophrenia. An intramuscular formulation will probably be available in the near future.