Biomarker Opportunities to Enrich Clinical Trial Populations for Drug Development in Schizophrenia and Depression

Developing new innovative and effective medications for such broad disease indications as schizophrenia and major depression is challenged by the great heterogeneity in pathophysiology and phenotype inherent in these clinical diagnoses. Targeting development efforts to a subset of those patients who may share a homogeneous set of disease-mediating features may offer a more effective pathway for bringing drugs to market. Disease prognostic and treatment predictive biomarkers may be used to identify subpopulations of patients that are more likely to respond to a specific treatment. Enrichment of clinical trials with such tailored populations may enhance signal detection through testing potential drugs that target a disease substrate common to the patient cohort under investigation. Such an approach has the potential to improve the efficiency and success rate of the clinical trials for CNS drug development. Several examples from recent clinical trial investigations in schizophrenia and major depression illustrate the potential benefit of such an enrichment strategy. With increasing discovery and identification efforts for relevant prognostic and predictive biomarkers in schizophrenia and depression, an increased probability of successful drug development to meet unsatisfied therapeutic needs across major psychiatric disorders may be achieved.