Saccharomyces boulardii with amoxicillin to protect gut bacteria during early Lyme rash treatment

Effect of Saccharomyces Boulardii CNCM I-745 on Gut Microbiota in Patients Undergoing Antibiotic Therapy (in the Context of Erythema Migrans (Early Skin Form of Lyme Borreliosis))

This test will see if taking the probiotic Saccharomyces boulardii with prescribed amoxicillin helps protect gut bacteria and reduce gastrointestinal symptoms in adults treated for erythema migrans.

Quick facts

• Phase: Phase 4
• Study type: Interventional
• Enrollment: 120 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Biocodex (Industry-sponsored)
• Drugs / interventions: chemotherapy
• Locations: 1 site (Ljubljana)
• Trial ID: NCT06451913 on ClinicalTrials.gov

What this trial studies

Adults with erythema migrans who are prescribed routine amoxicillin (1000 mg twice daily for 14 days) will receive either Saccharomyces boulardii CNCM I-745 500 mg twice daily or a matching placebo alongside their antibiotic. Participants will provide stool samples and complete symptom measures including the Bristol Stool Form Scale and the Gastrointestinal Symptom Rating Scale to track changes in gut microbiota composition and GI symptoms. The study compares microbiome and symptom outcomes between the probiotic and placebo groups during and after antibiotic therapy. Eligibility includes age ≥18, regular bowel movements, ability to complete diaries and sample collection, and appropriate pregnancy testing/contraception for women of childbearing potential.

Who should consider this trial

Good fit: Adults aged 18 or older who are prescribed amoxicillin 1000 mg twice daily for 14 days for erythema migrans, can provide stool samples and diary entries, and meet pregnancy-test/contraception requirements if applicable.

Not a fit: Patients not receiving amoxicillin, those with irregular bowel habits (fewer than about three bowel movements per week), or with conditions that interfere with study assessments are unlikely to benefit from this intervention.

Why it matters

Potential benefit: If successful, the probiotic could reduce antibiotic-related disruption of the gut microbiome and lessen gastrointestinal symptoms in adults treated for early Lyme rash.

How similar studies have performed: Previous studies have shown Saccharomyces boulardii can reduce antibiotic-associated diarrhea and help preserve gut microbiota, so this approach builds on existing evidence though context-specific data in Lyme-related antibiotic use are limited.

Eligibility criteria

Inclusion Criteria:

* Adult Patients, ≥18 years old.
* Who are prescribed antibiotic therapy (as per medical routine practices, amoxicillin 1000 mg bid for 14 days) in the context of erythema migrans (early skin form of Lyme borreliosis).
* Able to comply with study requirements and to provide signed informed consent before any study procedure.
* Has no condition that may interfere with the study assessments.
* Able to fulfil in the diary stool log, according to the physician's opinion.
* Regular defecation (frequency and stool consistency, with at least about three bowel movements a week).
* For women of childbearing potential:
* A negative urine pregnancy test immediately prior to starting the study treatment,
* Agreement to comply with approved methods of contraception during the whole study: unless they meet the criteria of post-menopausal, i.e. 12 months of spontaneous amenorrhea, women of child-bearing potential, defined as all women physiologically capable of becoming pregnant, including women whose career, lifestyle, or sexual orientation precludes intercourse with a male partner, should use one or more acceptable methods of contraception that should be maintained throughout the study.

Exclusion Criteria:

* History of hypersensitivity to the study treatments (active substance or excipients), brewer's or baker's yeast,
* Contraindication and special warning to the study drugs according to the SmPCs,
* History of chronic constipation with passage of fewer than 3 spontaneous bowel movements per week on average,
* History of chronic or recurrent diarrhoea with spontaneous unformed bowel movements equivalent to or more often than 3 times daily,
* Prior gastrointestinal surgery (apart from appendectomy or cholecystectomy performed at least more than one year ago),
* History of Clostridium difficile infection,
* Active gastrointestinal inflammatory disease,
* Known chronic or recurrent systemic disorder that may interfere with the study drug evaluation,
* Immunocompromised (organtransplants, leukaemia, malignant tumours, radiotherapy, chemotherapy,prolonged high dose cortisone treatment, immunosuppressant treament) or critically ill patients (such as autoimmune disease, HIV,…), patients with a central venous catheter,
* Severe hepatic or renal impairment,
* Systemic antibacterial therapy during the 2 months prior to study enrollment,
* New prescription medications during the 2 weeks prior to study enrollment,
* Use of any drug or product that alters gut microbiota or function, such as probiotics, laxatives, antiemetics, cisapride, antisecretory or adsorbent treatments (racecadotril, smectite, activated charcoal), opiates such as loperamide, atropine and other cholinergic agents, 4 weeks prior to study enrollment and during the study,
* Intake of antifungals within 14 days prior to study enrollment,
* Substantial changes in eating habits within 30 days prior to receiving the first dose of IMP product, and during the study as assessed by the Investigator,
* History or presence of drug or alcohol abuse,
* Heavy smoker (more than 10 cigarettes per day),
* Breast-feeding woman,
* Patients enrolled in another interventional clinical trial where they received an investigation treatment within the past 30 days,
* Any condition or personal circumstance that, in the opinion of the investigator, rendered the subject unlikely or unable to comply with the full study protocol

Where this trial is running

Ljubljana

• University Medical Centre Ljubljana — Ljubljana, Slovenia (Recruiting)

Study contacts

• Study coordinator: Gaëlle MARIAULE

Conditions Erythema Migrans of Lyme Disease; Erythema Migrans; Lyme Disease; Gut microbiota; Saccharomyces boulardii CNCM I-745; Lyme borreliosis