A Study to Explore the Effect of SP-624 on Brain Network Analytics in Healthy Adults and Adults With Major Depression

A Phase 1, Single-Center, Double-Blind, Randomized, Placebo-Controlled Study to Explore the Effect of SP-624 on Brain Network Analytics in Cohorts of Healthy Adult Subjects and Subjects With Major Depressive Disorder

The main goal of this clinical trial is to learn if the active study drug (code name: SP-624) has any effect on the electrical activity of the brain in adult healthy volunteers and in adults with major depression. Another goal of the study is to learn if SP-624 improves memory and learning in adults with major depression. The study will also provide additional information on the safety of SP-624 and how well it is tolerated in adult healthy volunteers and adults with major depression.

Researchers will compare SP-624 to a placebo (a look-alike substance that contains no drug) to see if SP-624 has any effect on study tests.

Study participants will:

Take capsules of study drug (SP-624 or a placebo) once daily for 2 weeks; visit the clinic at Screening, Day 1 (first dose of study drug), and Day 15 (last dose of study drug) for checkups and tests; and have phone call check-ups on Day 7 and about 1 week after the last dose of study drug.

Key Inclusion Criteria:

• In generally good health
• Body mass index (BMI) between 18.0 and 40.0 kg/m2
• Willing to comply with the requirements of the study
• For participants with depression: must meet study criteria for moderate to severe major depressive disorder

Key Exclusion Criteria:

• Female who is pregnant or breastfeeding.
• Clinically significant health condition or clinically significant abnormal results on screening health tests
• For participants with depression: presence of exclusionary study criteria for co-morbid psychiatric conditions or medication history.