Table 1.

Subtype selective compounds for GABA_A receptors

Compound	Receptor subtype	Binding/Functional selectivity	Indication	Development status
L-838,417	Partial agonist at α2, α3, α5	Functional	Anxiolytic	Preclinical
TPA023 (MK-0777)	Partial agonist at α2, α3	Functional	Anxiolytic, Schizophrenia	Phase 2
TPA023B	Partial agonist at α2, α3	Functional	Anxiolytic, Schizophrenia	Phase 1
TPA123	Partial agonist at α1, α2, α3, α5	Functional	Anxiolytic	On hold
MRK-409 (MK-0343)	Partial agonist at α2, α3	Functional	Anxiolytic	Phase 1/Halted
TP003	Agonist at α3	Functional	Anxiolytic	On hold
Ocinaplon	Partial agonist at α2, α 3, α5	Functional	Anxiolytic	On hold
NS11394	Full agonist at α1	Functional	Anxiolytic	Preclinical
	Agonist at α5
	Partial agonist at α3, α5
MRK-016	Full inverse agonist at α5	Functional	Cognition enhancer	Phase 1/Halted
α5IA	Partial inverse agonist at α5	Functional	Cognition enhancer	Phase 1/Halted
RO4938581	Full inverse agonist at α5	17–40-fold binding selectivity for α5	Cognition enhancer	Preclinical
L-655,708 (FG8094)	Very weak inverse agonist at α5	30–70-fold binding selectivity for α5	Cognition enhancer	Preclinical
SH-053-2′F-R-CH3	Full agonist at α5	8–10-fold binding selectivity for α5	Schizophrenia ?	Preclinical
	Partial agonist at α1, α2, α3
Gaboxadol	Supra-maximal agonist at α4β3δ	> 10-fold binding selectivity for α4	Hypnotic	Phase 3/Halted