The purpose of this research study is to examine how well a medication called lumateperone (Caplyta) works to relieve depression in older adults with treatment-resistant depression. Lumateperone (Caplyta) is approved by the U.S. Food and Drug Administration to treat Major Depressive Disorder in adults who are also taking another antidepressant medication. This study will compare lumateperone (Caplyta) to placebo (a sugar pill without medication).

This study is a 10-week, randomized, double-blind, placebo-controlled clinical trial designed to evaluate the efficacy and safety of adjunctive lumateperone in older adults with treatment-resistant depression (TRD). Approximately 100 participants aged ≥60 years with unipolar, non-psychotic major depressive disorder will be enrolled across two study sites. Participants will continue their existing antidepressant medication at a stable dose throughout the study and will be randomized to receive either lumateperone or matching placebo administered adjunctively during the treatment phase.

• Screening: Participants who sign consent will go through a screening process. This will involve answering questions about medical history, medications, demographics, mood and emotions as well as completing a brief cognitive test.
• Baseline: If the participant is eligible from the screening visit, they will complete a baseline visit in our research clinic. This will involve answering questions and completing questionnaires about mood and emotions, completing tasks on an iPad to assess thinking, attention, and memory as well as a physical exam. The physical exam will include gathering height and weight, an evaluation for potential medication side effects, a fasting blood draw to measure blood lipids and glucose, and an electrocardiogram (ECG).
• Study Medication: Participants will be randomized (like flipping a coin) to take either lumateperone or placebo (sugar pill). The research team and participant will be blinded to each participant's study medication. Participants will not get to choose whether they take lumateperone or placebo.
• Monitoring visits: We will ask participants to complete visits in the research clinic after one week, two weeks, four weeks, six weeks, and eight weeks following the baseline visit. These visits will be to assess depression symptoms, medication changes, and side effects. We may ask participants to complete additional visits in person or over the phone if they are needed to manage side effects or worsening in depressive symptoms.
• Endpoint visit: After 10-weeks we will ask participants to complete an endpoint visit in the research clinic to measure the effects of lumateperone or placebo. This visit includes answering questions and completing questionnaires about mood and emotions, medication changes, and side effects. Participants will complete tasks on an iPad to assess your thinking, attention, and memory. There will also be a fasting blood draw to measure blood lipids and glucose as well as another ECG.
• Extra visit (if needed): We may ask participants to complete one additional endpoint visit for a final assessment of symptoms.

Inclusion Criteria:

• Age >=60
• Current unipolar non-psychotic major depression determined by SCID-5
• MADRS score >=20 at screening and >=18 at baseline
• Treatment-resistance defined as documented history of non-response to at least two oral medications of adequate dose and duration in this episode or previous episode, OR clinician determination that treatment augmentation is appropriate
• Currently taking oral antidepressant prescribed at least minimum therapeutic dose and for at least six weeks duration
• MMSE score of >/=24

Exclusion Criteria:

• Dementia
• High risk for suicide, defined as a 4 or 5 on C-SSRS (indicating active suicidal ideation with current or recent intent or plan), and unable to be managed safely in the clinical trial. Urgent psychiatric referral will be made in these cases.
• High risk alcohol use: defined as a score of 6 or more on the AUDIT-C
• Medically inappropriate for participation as determined by PIs.

Contact PI