Probiotic Administration for Adolescent Depression

This double-blind, placebo-controlled clinical trial will examine the effect of probiotic Visbiome on the brain and gut microbiome of individuals 15 to 24 years of age.

This trial will evaluate the effects of Visbiome 450 billion CFU taken orally twice daily on the biological signature of left hippocampal (HP) resting-state functional connectivity (RSFC) and gut microbiome composition in individuals between the ages of 15 and 24 years.This study will assess the safety and tolerability of Visbiome at this dosage. Participants will be enrolled in the study for a total of eight weeks and randomized to the probiotic or placebo group. Follow-up assessments will take place every two weeks and will be conducted either through Zoom video visits or in person. The primary outcomes of the study include the effects of the intervention on neural connectivity and gut microbiome composition. Neural connectivity will be assessed by measuring the left HP RSFC using functional magnetic resonance imaging (fMRI). Gut microbiome composition will be evaluated by assessing beta diversity through stool samples collected at baseline and post-intervention. The safety and tolerability of the intervention will be carefully monitored throughout the study. Adverse events will be systematically collected at each visit, graded for severity, and evaluated for their relationship to the probiotic intervention. Tolerability will be assessed using the Generic Assessment of Side Effects - Probiotics (GASE-P). This measure will be administered at baseline and every two weeks throughout the study period.