To evaluate the relapse prevention of AXS-05 relative to placebo in subjects with treatment resistant depression (TRD).

This is a randomized, double-blind, placebo-controlled study to evaluate AXS-05 compared to placebo in delaying relapse of depressive symptoms in patients with TRD who are in stable remission after treatment with AXS-05.

Key Eligibility Criteria:

• Ongoing symptoms of depression despite receiving treatment with two or more prior antidepressants during the current major depressive episode, prior to receiving AXS-05
• Agree to use adequate method of contraception for the duration of the study
• Additional criteria may apply

Double (Participant, Investigator)