A Phase 2 interventional study of Probiotic Agent and Placebo in Post-Acute COVID-19 Syndrome, sponsored by Rush University Medical Center. Completed at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-08-07.
Sponsored by Rush University Medical Center · Phase 2, Interventional, and Treatment
The goal of this clinical trial is to learn if probiotics can improve symptoms and quality of life in participants with Long COVID.
The goal of this clinical trial is to learn if probiotics can improve symptoms and quality of life in participants with Long COVID. The main questions it aims to answer are:
Researchers will compare probiotics to a placebo (a look-alike substance that contains no probiotics) to see if probiotics work to treat Long COVID.
Participants will take the study medication (placebo or probiotic) for 4 months. They will then cross over (take the other medication) for an additional 4 months. Participants will complete a survey at baseline, 4 months, and 8 months.
520 studies on the registry are indexed under Post-Acute COVID-19 Syndrome; 186 are open to participants now.
This study's enrollment of 194 is above the median of 60 across 361 interventional studies indexed under Post-Acute COVID-19 Syndrome.
Browse Post-Acute COVID-19 Syndrome studies →Rush University Medical Center is the lead sponsor of 394 studies on the registry; 61 are open to participants now.
Of its 30 completed or terminated interventional studies of FDA-regulated products, 25 (83%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Probiotic pill taken once daily
Drug: Probiotic Agent
Identical placebo pill taken once daily
Other: Placebo
BlueBiology: Ultimate Care probiotic pill taken once daily for a four-month period.
Also known as: BlueBiotics: Ultimate Care
Placebo produced to be identical in taste and appearance to the probiotic agent, taken once daily for a four-month period.
Difference in Long COVID Severity
Defined as the percentage change from moderate-to-severe Long COVID to mild Long COVID using the Long COVID Symptoms and Severity Score (LC-SSS) tool between groups with subgroup analysis by Long COVID trajectory
Time frame: Baseline, Four, and Eight Months
Difference in LC-SSS Total Score
Defined as the change in the LC-SSS total score between groups with subgroup analysis by individual symptom scores and Long COVID trajectory
Time frame: Baseline, Four, and Eight Months
Difference in Quality of Life
Defined as the change in score for PROMIS-29 physical and mental health and the PROMIS SF-Cognitive Function 8a scale between groups with subgroup analysis by Long COVID trajectory
Time frame: Baseline, Four, and Eight Months
Difference in Return to Work and Activity
Defined as the change in the Work Productivity and Activity Impairment tool scores between groups with subgroup analysis by Long COVID trajectory
Time frame: Baseline, Four, and Eight Months
Plan to share: No
No publications or documents are linked to this record.
This study is completed, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Rush University Medical Center