Please select the arm or intervention descriptions that belong to the clinical trial below.
Title: A Phase IIb, Multicenter, Randomized, Double-blind, Parallel Group, Placebo-controlled Efficacy and Safety Study of Adjunctive AZD6765 in Subjects With Severe Major Depressive Disorder (MDD) and a History of Poor Response to Antidepressants
Brief Summary: The purpose of this research study is to determine whether AZD6765 has an effect on the patient's depression when taken together with current depression medication. In addition, information will be gathered on how well AZD6765 is tolerated, investigate the levels of AZD6765 and the levels of the current depression medication in the blood. In addition, the research staff will determine if AZD6765 has any mood or calming effects (how you feel).


Options:
A: Arm Label: A: Ketamine + Naltrexone or placebo; Type: EXPERIMENTAL; Interventions: Drug: Naltrexone | Arm Label: B: Ketamine + Naltrexone or placebo; Type: EXPERIMENTAL; Interventions: Drug: Naltrexone | Intervention Type: DRUG; Name: Naltrexone; Assigned to Arm(s): A: Ketamine + Naltrexone or placebo, B: Ketamine + Naltrexone or placebo
B: Arm Label: 1; Type: EXPERIMENTAL; Interventions: Drug: AZD6765 | Arm Label: 2; Type: EXPERIMENTAL; Interventions: Drug: AZD6765 | Arm Label: 3; Type: PLACEBO_COMPARATOR; Interventions: Drug: Placebo | Intervention Type: DRUG; Name: AZD6765; Assigned to Arm(s): 1, 2 | Intervention Type: DRUG; Name: Placebo; Assigned to Arm(s): 3
C: Arm Label: Intranasal Esketamine 84mg plus Oral Antidepressant; Type: EXPERIMENTAL; Interventions: Drug: Esketamine, Drug: Duloxetine (Oral Antidepressant), Drug: Escitalopram (Oral antidepressant), Drug: Sertraline (Oral Antidepressant), Drug: Venlafaxine Extended Release (XR) (Oral Antidepressant) | Arm Label: Esketamine 56 mg plus Oral Antidepressant; Type: EXPERIMENTAL; Interventions: Drug: Esketamine, Drug: Duloxetine (Oral Antidepressant), Drug: Escitalopram (Oral antidepressant), Drug: Sertraline (Oral Antidepressant), Drug: Venlafaxine Extended Release (XR) (Oral Antidepressant) | Arm Label: Placebo plus Oral Antidepressant; Type: ACTIVE_COMPARATOR; Interventions: Drug: Placebo, Drug: Duloxetine (Oral Antidepressant), Drug: Escitalopram (Oral antidepressant), Drug: Sertraline (Oral Antidepressant), Drug: Venlafaxine Extended Release (XR) (Oral Antidepressant) | Intervention Type: DRUG; Name: Esketamine; Assigned to Arm(s): Esketamine 56 mg plus Oral Antidepressant, Intranasal Esketamine 84mg plus Oral Antidepressant | Intervention Type: DRUG; Name: Placebo; Assigned to Arm(s): Placebo plus Oral Antidepressant | Intervention Type: DRUG; Name: Duloxetine (Oral Antidepressant); Assigned to Arm(s): Esketamine 56 mg plus Oral Antidepressant, Intranasal Esketamine 84mg plus Oral Antidepressant, Placebo plus Oral Antidepressant | Intervention Type: DRUG; Name: Escitalopram (Oral antidepressant); Assigned to Arm(s): Esketamine 56 mg plus Oral Antidepressant, Intranasal Esketamine 84mg plus Oral Antidepressant, Placebo plus Oral Antidepressant | Intervention Type: DRUG; Name: Sertraline (Oral Antidepressant); Assigned to Arm(s): Esketamine 56 mg plus Oral Antidepressant, Intranasal Esketamine 84mg plus Oral Antidepressant, Placebo plus Oral Antidepressant | Intervention Type: DRUG; Name: Venlafaxine Extended Release (XR) (Oral Antidepressant); Assigned to Arm(s): Esketamine 56 mg plus Oral Antidepressant, Intranasal Esketamine 84mg plus Oral Antidepressant, Placebo plus Oral Antidepressant
D: Arm Label: Intranasal Esketamine plus oral antidepressant; Type: EXPERIMENTAL; Interventions: Drug: Esketamine, Drug: Duloxetine (Oral Antidepressant), Drug: Escitalopram (Oral antidepressant), Drug: Sertraline (Oral Antidepressant), Drug: Venlafaxine Extended Release (XR) (Oral Antidepressant) | Arm Label: Placebo plus oral antidepressant; Type: ACTIVE_COMPARATOR; Interventions: Drug: Placebo, Drug: Duloxetine (Oral Antidepressant), Drug: Escitalopram (Oral antidepressant), Drug: Sertraline (Oral Antidepressant), Drug: Venlafaxine Extended Release (XR) (Oral Antidepressant) | Intervention Type: DRUG; Name: Esketamine; Assigned to Arm(s): Intranasal Esketamine plus oral antidepressant | Intervention Type: DRUG; Name: Placebo; Assigned to Arm(s): Placebo plus oral antidepressant | Intervention Type: DRUG; Name: Duloxetine (Oral Antidepressant); Assigned to Arm(s): Intranasal Esketamine plus oral antidepressant, Placebo plus oral antidepressant | Intervention Type: DRUG; Name: Escitalopram (Oral antidepressant); Assigned to Arm(s): Intranasal Esketamine plus oral antidepressant, Placebo plus oral antidepressant | Intervention Type: DRUG; Name: Sertraline (Oral Antidepressant); Assigned to Arm(s): Intranasal Esketamine plus oral antidepressant, Placebo plus oral antidepressant | Intervention Type: DRUG; Name: Venlafaxine Extended Release (XR) (Oral Antidepressant); Assigned to Arm(s): Intranasal Esketamine plus oral antidepressant, Placebo plus oral antidepressant

Answer: B