Schizophrenia Drug Face-Off: No Clear Winner
Surprise Finding: Older Antipsychotics Can Be as Good as New Ones
'Traditional' Drug vs. Newer 'Atypical' Drugs continued...
Clinical trials show that the drugs work better than no drugs at all. But the trials never told doctors how the drugs would work relative to one another. That's why the NIMH sponsored the trial, known as the Clinical Antipsychotic Trials of Intervention Effectiveness or CATIE.
The trial included Trilafon to represent the traditional antipsychotic drugs. It also included four other atypical antipsychotics. Clozaril was not included in the first phase of the trial because it will be tested as a second-line treatment for patients who switch from one of the original drugs in the trial. Those results will be reported later.
A sixth atypical antipsychotic drug, Abilify, wasn't included because the FDA had not approved it by the time of the trial.
What happened in phase 1 of the CATIE trial?
"Zyprexa was somewhat better in efficacy but had the most side effects," Lieberman said. "The biggest surprise was that the oldest medication [Trilafon] was comparable to at least three of the new medications and not much worse than Zyprexa. Contrary to expectations, the old drug did not cause more Parkinson's symptoms than the new drugs."
Some scientists involved in designing the study hadn't even thought the old drugs were worth including in the trial, says study investigator Robert Rosenheck, MD, of Yale University.
"Many of us thought the question was decided and the old drugs were of no value," Rosenheck said at the news conference. "Because we were willing to ask a question that most people thought they knew the answer to, we were able to get a surprising answer."
Doctors Get New Insight
The study findings aren't what everyone hoped for, notes University of Colorado researcher Robert Freedman, MD, in an editorial accompanying the CATIE report.
"The results could be viewed as discouraging," Freedman writes. "No drug provided the majority of patients a treatment that lasted the full 18 months of the study. ... Only 36% of the patients receiving the most effective drug, [Zyprexa], completed the trial."
But Rosenheck tells WebMD that patients who are happy with their schizophrenia medication don't enter clinical trials.