Lanicemine (AZD6765) is an NMDA antagonist developed by AstraZeneca, which is being studied for the treatment of major depression. It was originally developed as a neuroprotective agent, but was redeveloped as an antidepressant following the observation that the anesthetic drug ketamine has potent antidepressant effects, but also has hallucinogenic side effects which make it unsuitable for use as an antidepressant in most circumstances.