Pilot study evaluating the efficacy of subcutaneous ketamine for the treatment of depression in the elderly

Open-label, non-randomised, single-group Phase II study in older adults (≥65) with MDD (n=24). Phase 1: all participants receive subcutaneous ketamine 0.3 mg/kg then 0.6 mg/kg one week apart; responders may enter Phase 2 maintenance.

Primary outcome is change in Geriatric Depression Scale (GDS). Phase 2 maintenance dosing is individualised (1–2x/week up to 3 months). Safety and tolerability monitored throughout.