The FDA-NIMH-MATRICS guidelines for clinical trial design of cognitive-enhancing drugs: what do we know 5 years later?

The Food and Drug Administration (FDA)-National Institute of Mental Health (NIMH)-Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) clinical trial guidelines for cognitive-enhancing drugs in schizophrenia and the MATRICS Consensus Cognitive Battery (MCCB) were designed to facilitate novel compound development in the treatment of cognitive impairments. Several studies have recently utilized the FDA-NIMH-MATRICS guidelines and MCCB and allow an evaluation of the feasibility of guideline implementation and MCCB performance. In light of the study results, we would recommend the following inclusion criteria revisions-(1) clinical status and symptom inclusion criteria: maximum allowed score for hallucinations and delusions should be increased from moderate to moderately severe and the negative symptom criterion should be dropped in phase 2 studies; (2) antipsychotic medication inclusion criteria: first-generation antipsychotics should be allowed, but only in the context of no concomitant anticholinergic agents and minimal extrapyramidal symptoms, and antipsychotic polypharmacy should be allowed in the absence of pertinent pharmacokinetic or pharmacodynamic considerations; and (3) people who use illicit substances should not be allowed in phase 1B or 2A proof-of-concept studies but may be included in phase 2B and 3 studies in which proof of effectiveness and generalizability of results become more important goals. These revisions are recommended to enhance recruitment while maintaining sufficient methodological rigor to ensure the validity of study results. The MCCB has been shown to have excellent psychometric characteristics, including reliability for multisite clinical trials, clinical relevance for real-world functioning, and possible sensitivity to behavioral treatment, and should continue to serve as the standard outcome measure for cognitive enhancement studies in schizophrenia.