Predictive Models and Enrichment Study Design Strategies

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Registration is open for the: Special Course on Predictive Models and Enrichment Study Design Strategies October 20-22, 2014: The Carolina Inn on the Campus of the University of North Carolina at Chapel Hill, NC (USA) This is a 3-day advanced course designed to help scientists to develop and use predictive models for implementing enrichment study design with particular emphasis in CNS diseases. The very high frequency of failed and negative clinical trials has been recognized as a critical issue for the clinical development of novel antidepressant treatments. A trial is considered failed when the reference treatment does not differentiate from placebo. The level of placebo response has been shown to strongly affect the probability of detecting active treatment superiority. Furthermore, growing evidence indicates that placebo responses in antidepressant and antipsychotic trials have been gradually increasing over time. These findings indicate that there is an urgent need for exploring, evaluating and implementing novel study design to counteract the uncontrolled and time varying level of placebo response and for improving the overall efficiency of clinical trials. In this workshop, we will present and discuss different methodologies for improving the efficiency of placebo-controlled clinical trial of antidepressant drugs by implementing novel study designs and novel methodologies for data analysis. In particular we will discuss the use of enrichment strategies that have been recommended as an effective methodology for improving the efficiency of drug development [Guidance for Industry Enrichment Strategies for Clinical Trials to Support Approval of Human Drugs and Biological Products. Draft Guidance. December 2012]. Three study design strategies will be presented: the sequential parallel comparison design (SPCD) recommended for reducing both the placebo response and the required sample size, the lead-in study design to screen out patients who are likely to be placebo responders using data collected in in a short double blinded placebo lead-in phase, and the adaptive randomization design (ARD) to identify, during the patients accrual process, uninformative centers (centers with excessively low or excessively high placebo response) in an ongoing clinical trial and, based on this information, to implement an adaptive randomization scheme to stop the inclusion of patients in the uninformative centers and increase the inclusion of patients in the informative centers. Two novel methodologies for data analyses will be discussed. The first one, classified as a post-hoc analysis, is based on a novel analytic technique called band-pass filter to minimize the interference of confounding signals such as the ones associated with excessively high or low placebo response characterizing the placebo response in the different recruitment centers. The second methodology proposes a novel approach for estimating the treatment effect (TE) using a Non-Linear Mixed-Effect Model for Repeated Measures approach (NLMMRM). NLMMRM can be considered as the natural generalization of the likelihood-based mixed-effects model for repeated measures (MMRM) approach that is today recognized as the most efficient and reliable method for conducting the primary analysis of continuous endpoints in longitudinal clinical trials. The novel data analysis approach is based on the use of the center-specific level of placebo response as a weighting factor in the evaluation of TE assuming that centers with high placebo response are less informative than the others for estimating the 'true' treatment effect. We will discuss how placebo response models can be used to build prior knowledge on the expected time-course of placebo response and how disease progression models can be used to predict the individual disease trajectory deterioration shape. During the workshop we will illustrate how probabilistic models can be used for classifying subjects as placebo responders or slow/fast disease progressors using a Bayesian framework applied to information collected in an early phase of the trial. The workshop includes lectures and hands-on training on concepts, applications, and software tools. Cases-study in Depression, Alzheimer's disease and in a Rare Diseases (Amyotrophic Lateral Sclerosis) will be used to implement study design where patients with more rapid progression are selected based on a disease-progression model. Additional details on the workshop are available at: http://www.pharmacometricaworkshop.webs.com www.pharmacometricaworkshop.webs.com References R. Gomeni and E. Merlo-Pich. Bayesian modeling and ROC analysis to predict placebo responders using clinical score measured in the initial weeks of treatment in depression trials. Br J Clin Pharmacol. May;63(5):595-613, 2007. E Merlo-Pich and R Gomeni. Model-based Approach and Signal Detection Theory to Evaluate the Performance of Recruitment Centers in Clinical Trials with Antidepressant Drugs. Clin Pharmacol Ther. 2008 Sep;84(3):378-84. E. Merlo-Pich, R. C. Alexander, M. Fava, R. Gomeni. A new population enrichment strategy to improve efficiency of placebo-controlled clinical trial in depression. Clin. Pharmacol. Ther., 2010 Nov;88(5):634-42. R. Gomeni, E. Merlo-Pich. Trial Simulation to estimate Type I error when a population window enrichment strategy is used to improve efficiency of clinical trials in depression. Eur Neuropsychopharmacol. 2012 Jan;22(1):44-52. R. Gomeni, M. Simeoni, M. Zvartau-Hind, M. Irizarry, M. Gold. Disease System Analysis approach for modelling Alzheimer's disease progression in subjects on stable acetylcholinesterase inhibitors therapy. Alzheimers Dement. 2012 Jan; 8(1):39-50. N. Goyal and R. Gomeni. Exposure-Response modeling of anti-depressant treatments: the confounding role of placebo effect. J Pharmacokinet Pharmacodyn. 2013; 40(3):389-99. R. Gomeni R, M. Fava. The Pooled Resource Open-Access ALS Clinical Trials Consortium. Amyotrophic lateral sclerosis disease progression model. Amyotroph Lateral Scler Frontotemporal Degener. 2014 Mar;15(1-2):119-29 R. Gomeni. Use of predictive models in CNS diseases. Current Opinion in Pharmacology. 2014; 14: 23-29. S. Yang, R. Gomeni, M. Beerahee. Does Short-Term Placebo Response Predict the Long-Term Observation? Meta-Analysis on Forced Expiratory Volume in 1 Second From Asthma Trials. The Journal of Clinical Pharmacology, 2014, DOI: 10.1002/jcph.329 [Epub ahead of print]. R. Gomeni and N. Goyal. Adaptive Randomization Study Design in Clinical Trials for Psychiatric Disorders. J Biomet Biostat 2014, 5:187,1-6