[Comment] Enhancing cognitive function in schizophrenia: we must make better choices

In this issue of the Lancet Psychiatry, Richard S E Keefe and colleagues1 report on the findings from a set of three phase 3 randomised, placebo-controlled, double-blind clinical trials of a drug called iclepertin for the treatment of cognitive impairment associated with schizophrenia (CIAS). Iclepertin is a selective GlyT1 inhibitor that was designed to try to improve NMDA receptor hypofunction in schizophrenia, one mechanism hypothesised to contribute to CIAS.