A Safety Trial to Evaluate an Orally Ingested Yeast Modified to Express a Tetra-specific Anti-tox… (NCT07649096) | Clinical Trial Compass
Not Yet RecruitingPhase 1
A Safety Trial to Evaluate an Orally Ingested Yeast Modified to Express a Tetra-specific Anti-toxin for Clostridioides Difficile
86 participantsStarted 2026-06-15
Plain-language summary
This is a Phase 1, first-in-human, double-blind, placebo-controlled, adaptive-design, single-site study, involving dose exploration cohorts.
During Part A, up to 4 cohorts, each consisting of approximately 14 healthy adult study participants, will be randomly allocated to receive either FZ002 or placebo. Part A is designed to begin with Cohort 1 evaluating the highest proposed dose of study product. This is intended to represent the "ceiling" (highest level) of the ranges of doses to be evaluated in the study. In the event of a safety or tolerability concern in Cohort 1, a dose de-escalation will be evaluated in Cohorts 2-4 until a safe and well-tolerated dose is identified. If no safety or tolerability concerns are identified at the completion of a cohort, the study will proceed to Part B with the approval of the independent Safety Monitoring Committee (SMC). This adaptive design allows for the progression of the study from Part A to Part B without necessarily progressing through all 4 cohorts in Part A if there is a lack of safety or tolerability concerns.
During Part B, an initial 'sentinel' Cohort 5 "some-risk" adult study participants will be randomly allocated to receive a single daily dose of FZ002 or placebo for 28 consecutive days. This is intended to represent the "floor" (lowest level) of doses to be evaluated in the study. A Protocol Safety Review Team (PSRT) will review the available safety data from the first 7 days of Cohort 5. If there is a lack of safety or tolerability concerns over the first 7-days of dosing for Cohort 5, then Cohort 6 will be opened for enrollment. Cohort 6 "some-risk" adult study participants will evaluate the "floor" and "ceiling" dose of FZ002 versus placebo.
The primary objective is to evaluate safety and clinical tolerability of oral doses of FZ002 or placebo when taken for up to 28 days.
Who can participate
Age range
18 Years – 75 Years
Sex
ALL
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
Inclusion criteria
. Provides written informed consent prior to the initiation of any trial procedures.
. Is able to understand and agrees to comply with all planned trial procedures and be available for all study visits, including:
. Receiving 28 days of blinded oral study product
. Providing blood and self-collected stool samples
. Is a non-pregnant individual, aged 18-75 years, inclusive, at the time of enrollment.
. Has no more than 1 single Grade 1 screening laboratory abnormality that is not clinically significant. If the participant has more than 1 Grade 1 abnormality, it must be approved by the Division of Microbiology and Infectious Diseases \[DMID\] Medical Monitor (MM).
Questions worth asking your doctor
Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.
1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?
Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
Questions for the trial coordinator
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
What they're measuring
1
Occurrence of serious adverse events (SAEs)
Timeframe: Through Day 208
2
Occurrence of solicited adverse events (AEs)
Timeframe: Through Day 35
3
Occurrence of unsolicited AEs
Timeframe: Through Day 57
4
The occurrence of any positive yeast blood culture for Saccharomyces
Timeframe: Days 8 and 29
Trial details
NCT IDNCT07649096
SponsorNational Institute of Allergy and Infectious Diseases (NIAID)
. Participants of childbearing potential: use of adequate contraception for at least 4 weeks prior to enrollment and agreement to use such a method during trial participation and for an additional 4 weeks after the last dose of blinded study product. Note: Definitions of participants of childbearing potential and adequate contraception are provided in Section 13.1.
. Agrees to refrain from ingestion of probiotics\* or fermented foods\*\* from 7 days prior to study product administration, while on blinded study product, and through Day 36 (Visit 6).
Exclusion criteria
. Dwells in a long-term care or skilled nursing facility (living independently with limited nursing care is allowable).
. Known to be pregnant or has a positive pregnancy test at screening or enrollment.
. Currently breastfeeding a child.
. Known to have significant hypersensitivity to any components of the study product; including S. boulardii (or any S. boulardii-based nutritional supplement), hydroxypropyl methylcellulose, and Microcrystalline cellulose \[MCC\].
. Known to have significant hypersensitivity to a first-line antifungal therapy (i.e., fluconazole or amphotericin B) against Saccharomyces.
. Known to be immunocompromised or have known or suspected congenital or acquired immunodeficiency, as determined by the investigator.
. Receipt of immunosuppressive therapy such as anti-cancer chemotherapy or radiation therapy within 3 years of enrollment.
. Receipt of chronic (\>/=14 days) immunosuppressive corticosteroids at a dose of \>/=20 mg prednisone daily or prednisone equivalent within 30 days of enrollment, including oral, parenteral, or high-dose inhaled\* corticosteroids.