Seventy participants completed the trial, from 72 initially randomized to one of the following 36-day treatment arms: onfasprodil 0.16 mg/kg infused once weekly; onfasprodil 0.16 mg/kg infused biweekly, alternating with biweekly placebo infusion; onfasprodil 0.32 mg/kg weekly; onfasprodil 0.32 mg/kg biweekly alternating with placebo; placebo weekly; and ketamine 0.5 mg/kg (not to exceed 40 mg) weekly. The investigators reported adjusted mean differences of pooled results vs placebo in MADRS reduction from baseline for onfasprodil 0.16 mg/kg, 0.32 mg/kg and ketamine of -8.25, -5.71, and -5.67, respectively. "There were fewer and less intense side effects, particularly with the lower dose (0.16 mg/kg), which was at least equivalent to the higher dose (0.32 mg), and perhaps slightly better." Dosing every other week will be much more acceptable to patients than weekly or twice per week," Shelton pointed out. Rapid onset and sustained efficacy of onfasprodil (MIJ821), a novel NR2B Negative allosteric modulator, in patients with treatment-resistant depression: a phase 2, randomized, placebo-controlled, proof-of-concept study.