Testing the hypothesis that treatment with NRX-101 is superior to standard of care (lurasidone) in improving symptoms of depression as measured by the total Montgomery Åsberg Depression Rating Scale (MADRS-10) score in patients with bipolar depression and subacute suicidal ideation and behavior (SSIB) which does not require hospitalization.

 NMDA antagonist drugs have been shown to reduce symptoms of depression and suicidal ideation. NRX-101 is composed of D-cycloserine (DCS) an NMDA antagonist and lurasidone (5HT2a atypical antipsychotic and antidepressant). In the phase, 2 clinical study of bipolar depression and acute suicidal ideation and behavior, (in patients requiring hospitalization) patients received an initial infusion of ketamine and then NRX-101 for 6 weeks. In that phase 2 study, NRX-101 showed the ability to maintain remission from depression and suicidality over 6 weeks when taken twice daily. In this current outpatient study, for patients with bipolar depression and subacute suicidality (not requiring hospitalization), ketamine will not be used.