Patients with schizophrenia who fail to respond to standard antipsychotic medications have better outcomes if they begin taking the drug clozapine, an atypical antipsychotic drug, instead of moving on to another standard antipsychotic, according to a new study at Columbia University Medical Center.
Typically, when one traditional antipsychotic medication fails to yield results, clinicians change to another traditional antipsychotic. Clozapine is often seen as a drug of last resort, although it is the only medication approved by the FDA for treatment-resistant schizophrenia.
The findings show that while on clozapine, patients have fewer hospitalizations, tend to stay on the new medication longer and are less likely to need to use additional antipsychotics.
“These results give clinicians important guidance for how to help an extremely vulnerable group of people,” said T. Scott Stroup, M.D., lead author of the study, and professor of psychiatry at Columbia University Medical Center and a research psychiatrist at New York State Psychiatric Institute. “By helping individuals with treatment-resistant schizophrenia get effective treatment sooner we can expect better outcomes.”
Schizophrenia is a severe mental illness that affects approximately one percent of the adult population. Antipsychotics are effective at treating symptoms for most patients, but up to 30 percent do not respond well to these medications and are considered to have treatment-resistant schizophrenia.
While studies have shown that clozapine is effective for these cases, the effectiveness of clozapine in clinical practice has not previously been studied in depth.
For the study, researchers looked at national Medicaid data of 6,246 schizophrenia patients whose treatment patterns were consistent with treatment resistance. It is the largest study directly comparing the effectiveness of clozapine with standard antipsychotics in this population in routine practice settings.
The findings are encouraging and timely as the FDA recently broadened access to clozapine. Up until now, access to clozapine has been limited, in part because of the risk of agranulocytosis, a condition that can make people vulnerable to contracting infections. A system has been in place for 25 years to successfully manage the risks of agranulocytosis, using regular monitoring of white blood cell levels.
Leading experts thus believe the limits on use of clozapine have been overly restrictive. The new FDA rules still require regular blood monitoring, but allow physicians to make decisions based on benefits and risks for individual patients rather than rigidly following general standards.
The findings are published in the American Journal of Psychiatry.