Treatment Study of Bipolar Depression

Randomised, crossover, treatment trial in patients with treatment-resistant bipolar I or II depression evaluating safety and efficacy of a single IV ketamine infusion (0.5 mg/kg) versus active comparator midazolam (0.045 mg/kg) given two weeks apart.

Primary objectives are rapid antidepressant efficacy and safety; key inclusion requires IDS-C30 ≥32 and prior failure of at least three adequate pharmacotherapy trials; participants maintained on divalproex ER and off other psychotropics per protocol.