CTP354, also known as C-21191, a novel deuterated subtype-selective GABA(A) modulator. CTP may be potentially useful for treatment of neuropathic pain, spasticity and anxiety disorders. GABAA receptors are found in the nervous system and, when activated, reduce the transmission of certain nerve signals. Several classes of widely used drugs target GABAA receptors, including benzodiazepines, but do not have the receptor subtype selectivity of CTP-354.