ETX-155

ETX-155 is an oral, small-molecule neuroactive steroid that acts as a positive allosteric modulator of GABAA receptors, being developed by Climb Bio (formerly Eliem Therapeutics) for central nervous system disorders including depressive disorders and epilepsy.[3][4] As a GABAA receptor modulator, it enhances inhibitory GABAergic neurotransmission at both synaptic and extrasynaptic receptors, aiming to provide antidepressant, anxiolytic, and anticonvulsant effects with once-daily dosing enabled by a long half-life and minimal food-effect pharmacokinetics.[1][3] The compound has completed phase 1 studies in healthy volunteers, showed robust preclinical activity in seizure and depression models, and reached suspended development status in depressive disorders and seizures after a paused phase 2 program to investigate exposure variability between drug product lots.[1][3][4]