Open Label Ketamine Treatment for Major Depressive Disorder in Veterans

Open-label, single-group treatment trial of up to six IV ketamine infusions (0.5 mg/kg over 40 minutes) given once or twice weekly to Veterans with major depressive disorder; follow-up at 1, 3 and 6 months.

Primary objectives are to assess safety and tolerability in this population and to examine longer-term clinical effects; all participants continue usual standard care during the trial.