(Feb. 2, 2016) In the second half of 2015, the Food and Drug Administration (FDA) approved two new antipsychotic medications for oral use in the United States. Both are simply "me-too" drugs and do not add anything useful to the list of antipsychotics already available.
The first of these is brexpiprazola (trade name: Rexulti). The conception and birth of this drug makes an interesting story. It is manufactured by Otsuka Pharmaceuticals in partnership with Lundbeck. Otsuka also manufactures aripiprazole (Abilify), approved and heavily promoted for the treatment of schizophrenia, bipolar disorder, depression and autism. Sales of Abilify from mid-2013 to mid-2014 totaled $7.2 billion which, according to the research firm IMS Health, made Abilify the most profitable drug in the United States.
When Abilify Went Generic
Unfortunately for Otsuka, Abilify's patent expired; in 2014, a generic version was introduced. This means that, over time, the price of generic aripiprazole will fall sharply, along with Otsuka's profits. So what did Otsuka do? It simply introduced a chemically slightly altered version of aripiprazole, tested it against a placebo as the FDA requires, and presto—brexpiprazole (Rexulti) is being marketed as a new drug ... and sold for the treatment of schizophrenia and depression at about the same high price as Abilify was originally sold for. This is all perfectly legal. Since brexpiprazole has never been compared to aripiprazole in any published trial, it is not known whether it is any different at all.
In fact, aripiprazole (Abilify) is only an average antipsychotic when compared to other antipsychotics. In a definitive comparison of 15 antipsychotic drugs published in 2013 in Lancet, aripiprazole was rated as only average on efficacy and acceptability, considerably behind clozapine and amisulpride1 (which is sold in Europe, but not in the US).
Bottom line: According to the highly respected Medical Letter of August 17, 2015, "There is no reason to prescribe brexpiprazole over generic aripiprazole, which has a much longer record of efficacy and safety and should soon cost much less."
Cariprazine (Vrylar)
The other new antipsychotic to come to market in 2015 was cariprazine (trade name: Vraylar), manufactured by Forest Laboratories. Like the majority of existing antipsychotics already on the market, cariprazine has effects on both dopamine and serotonin receptors. There appears to be nothing unusual about it, including its side effects. Approved by the FDA for the treatment of both schizophrenia and bipolar disorder, it can be taken by mouth once daily, with or without food. The recommended dose for schizophrenia is 1.5 to 6 mg. per day and for bipolar disorder 3 to 6 mg. per day.
Consistent with FDA regulations, cariprazine was only tested against a placebo and to date no study has been carried out comparing it to any other existing antipsychotic. Bottom line: There is no reason so far to expect cariprazine to be any better than any of the existing antipsychotics. As a new antipsychotic on patent, it is likely only to be distinguished by its high cost.
E. FULLER TORREY, MD
Associate Director of Research, Stanley Medical Research Institute
Founder and member of the board, Treatment Advocacy Center
Co-chair, Psychiatric Advisory Board to the Treatment Advocacy Center
* Disclosure: John Davis, MD, the senior author on the Lancet paper, is on the staff of the Stanley Medical Research Institute, a supporting organization of the Treatment Advocacy Center, and a member of the Treatment Advocacy Center's Psychiatric Advisory Board.
References:
1 Leucht S, Cipriani A, Spinali L, et al. Comparative efficacy and tolerability of 15 antipsychotic drugs in schizophrenia: a multiple-treatments meta-analysis. Lancet 2013; 382: 951-962.
Next Week: What the Latest Schizophrenia News Means to Patients, Families and Communities
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