Schizophrenia experts interpret the result of an extensive head-to-head comparison of five treatments. Schizophrenia patients frequently change or discontinue treatments. The jury is out on some side effects.
Patients are about as happy with new schizophrenia drugs, some of which are a decade old, as they are with a drug from a half century ago, the initial results of a new study show.
The study, funded by the National Institutes of Health and published in the September 22 issue of the New England Journal of Medicine, measured the rate that patients taking one of five different drugs chose to stop treatment or change drugs. It is not uncommon for schizophrenia patients to change medications frequently.
All five of the drugs studied had high discontinuation rates. Zyprexa (olanzapine), a new drug, had the lowest rate at 64 percent. The 75 percent discontinuation rate for Etrafon, or Trilafon, (perphenazine)-a 1950s drug-was comparable to the second-generation drug Risperdal (risperidone) at 74 percent. It was also lower than the rates for the new drugs, Seroquel (quetiapine) at 82 percent, and Geodon (ziprasidone) at79 percent.
The researchers designed the study to evaluate not just symptoms but “functional measures” of schizophrenia treatment, said John Hsiao, NIMH’s government project officer for the study. Among these measures were patient satisfaction and compliance.
The results demonstrate that the current treatments are not entirely effective, he added. “Many patients only have partial responses to these agents and all of the drugs have substantial side effects,” said Stephen Marder, professor of psychology at the Semel Institute at the University of California Los Angeles. “None of the drugs clearly has an advantage over the others.”
The discontinuation rates are also high because doctors commonly change schizophrenia patients’ medications several times before they find the best option, explained Robert Rosenheck, professor of psychology at the Yale University School of Medicine and co-investigator on the study.
“In reality, clinicians use all of the medications until they find the right one,” said Leslie Citrome, professor of psychology at New York University’s School of Medicine.
Although olanzapine had the lowest discontinuation rate, it also had the most significant side effects, including weight gain and metabolic problems.
But the results available so far are unlikely to tell the whole story.
Marder pointed out that the 18-month trial was too short to detect the neurological side effect, tardive dyskinesia, that clinicians believe is stronger in older schizophrenia drugs. He also noted that trial participants with tardive dyskinesia were not put on the old drug, perphenazine, although the rest of the drugs were assigned randomly.
Although schizophrenia experts praised the study, they are waiting for additional results to be released. Many are particularly interested in the affect of different drugs on cognition, the patient’s ability to think. Although conclusive data is not yet available, some psychologists and clinicians hold that second-generation drugs are better at improving cognitive functions, Citrome said.
The investigators expressed concern that the partial results will prompt financial decision makers to push first-generation schizophrenia drugs like perphenazine, because they cost less than newer treatments.
“Government agencies will say perphenazine is just as good, so why not use perphenazine because it’s cheaper,” Citrome said.