Cipralisant (GT-2331) is an H3-receptor ligand developed by Gliatech in the late 1990s. The drug exhibits complex pharmacology: it behaves as an antagonist in a guinea pig jejunum contraction assay and mouse disogenia model, as a partial agonist in a rat brain synaptosome model, and as a full agonist at recombinant H3 receptors. In preclinical models, cipralisant enhanced wakefulness and improved learning in developmental rat models. In 2000 cipralisant was investigated in the clinical trials for the treatment of attention-deficit hyperactivity disorder, but due to the bankruptcy of Gliatech the development of the drug was discontinued.