Microbiome as a ThErapeutic Response Biomarker

To investigate the potential of gut microbiota as a biomarker of responsiveness to treatment and to evaluate treatment related changes in fecal microbiota composition among posterior segment uveitis patients.

Study Population: Up to 150 participants with uveitis may be enrolled in this study across up to 21 participating sites.

Design: This is a prospective, case-control ancillary study. Participants will be asked to provide a stool sample, blood sample, and complete an on-line Diet History Questionnaire (DHQ). The study will last approximately three years, with two years for recruitment and one year for follow-up. Participants must be co-enrolled in the parent ADVISE protocol (NCT 03828019.) in order to be eligible for this study.

Outcome Measures: The primary outcome answers whether there is a gut microbial signature at baseline that can predict therapeutic response among uveitis patients. Additionally, this study will explore whether the gut microbial ecology change differentially in response to conventional immunosuppressives or tumor necrosis factor inhibitors (TNFi) treatment. Secondary outcomes include exploring if there are molecular or immune phenotypic markers of activity or therapeutic response: To identify molecular correlates of disease activity and treatment response through transcriptional profiling (bulk ribonucleic acid (RNA) sequencing of whole blood samples collected in PAXgene tubes or a similar RNA stabilizing tube) and to identify immunophenotypic correlates of activity and treatment response through flow cytometry analysis (using Transfix tubes or a similar direct draw collection tubes used to stabilize venous blood at the point of collection and preserve whole blood specimens for immunophenotyping by flow cytometry.)