1. What is causing the reduced drug-placebo difference in recent schizophrenia clinical trials and what can be done about it?
- Author
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Kemp, Aaron S, Schooler, Nina R, Kalali, Amir H, Alphs, Larry, Anand, Ravi, Awad, George, Davidson, Michael, Dubé, Sanjay, Ereshefsky, Larry, Gharabawi, Georges, Leon, Andrew C, Lepine, Jean-Pierre, Potkin, Steven G, and Vermeulen, An
- Subjects
Humans ,Antipsychotic Agents ,Treatment Outcome ,Reproducibility of Results ,Interdisciplinary Communication ,Cooperative Behavior ,Schizophrenia ,Psychiatric Status Rating Scales ,Psychometrics ,Schizophrenic Psychology ,Bias (Epidemiology) ,Placebo Effect ,Dose-Response Relationship ,Drug ,International Cooperation ,Societies ,Medical ,Societies ,Pharmaceutical ,Multicenter Studies as Topic ,Randomized Controlled Trials as Topic ,Clinical Trials ,Phase III as Topic ,Bias ,schizophrenia ,clinical trials ,placebo response ,signal detection ,meeting summary ,ISCTM ,ISCDD ,Dose-Response Relationship ,Drug ,Societies ,Medical ,Pharmaceutical ,Clinical Trials ,Phase III as Topic ,Medical and Health Sciences ,Psychology and Cognitive Sciences ,Psychiatry - Abstract
On September 18, 2007, a collaborative session between the International Society for CNS Clinical Trials and Methodology and the International Society for CNS Drug Development was held in Brussels, Belgium. Both groups, with membership from industry, academia, and governmental and nongovernmental agencies, have been formed to address scientific, clinical, regulatory, and methodological challenges in the development of central nervous system therapeutic agents. The focus of this joint session was the apparent diminution of drug-placebo differences in recent multicenter trials of antipsychotic medications for schizophrenia. To characterize the nature of the problem, some presenters reported data from several recent trials that indicated higher rates of placebo response and lower rates of drug response (even to previously established, comparator drugs), when compared with earlier trials. As a means to identify the possible causes of the problem, discussions covered a range of methodological factors such as participant characteristics, trial designs, site characteristics, clinical setting (inpatient vs outpatient), inclusion/exclusion criteria, and diagnostic specificity. Finally, possible solutions were discussed, such as improving precision of participant selection criteria, improving assessment instruments and/or assessment methodology to increase reliability of outcome measures, innovative methods to encourage greater subject adherence and investigator involvement, improved rater training and accountability metrics at clinical sites to increase quality assurance, and advanced methods of pharmacokinetic/pharmacodynamic modeling to optimize dosing prior to initiating large phase 3 trials. The session closed with a roundtable discussion and recommendations for data sharing to further explore potential causes and viable solutions to be applied in future trials.
- Published
- 2010