Lubeluzole was developed as a neuroprotective substance for use in acute ischaemic stroke. Its biological function is related to its ability to alter the biochemical cascade that leads to irreversible neural damage in the penumbra by preventing an increase in extracellular glutamate and normalizing neuronal excitability in the peri-infarct region. Phase II and early phase III trials indicated an improvement in neurological outcome, whereas a final large randomized and placebo controlled trial did not show superiority versus placebo.