Placebo-controlled proof-of-concept clinical trials in (1) acute psychosis for IV OV350, and (2) chronic epilepsy and pain trials for oral AXN-027 will also pave the way for the next generation of KCC2 potentiation therapies, such as KCC2 expression-enhancing approaches, KCC2 gene therapies or alternative formulations/routes of administration tailored to patient’s needs (e.g., oral solution in ASDs/NDDs/DEEs; nasal spray for acute pain/seizures). This evidence concerns the gene SLC12A5 and psychotic disorder.