A Phase 1 interventional study of Best Practice and Clostridium butyricum CBM 588 Probiotic Strain in Hematopoietic and Lymphoid Cell Neoplasm, sponsored by City of Hope Medical Center. Active, not recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-04-07.
Sponsored by City of Hope Medical Center · Phase 1, Interventional, and Supportive care
This pilot trial studies the side effects and how well CBM588 works in improving clinical outcomes in patients who have undergone donor hematopoietic stem cell transplant. Gut microbiota (formerly called gut flora) is the name given to the microbe (bacteria) population living in the intestine. Gut bacteria help the body to digest certain foods that the stomach and small intestine have not been able to digest. CBM588, may increase gut bacteria biodiversity, prevent recurrent symptoms of gastrointestinal toxicity (ranging from diarrhea to life-threatening inflammation of the colon).
PRIMARY OBJECTIVES:
I. In patients with hematologic malignancies who are undergoing standard reduced intensity conditioning regimen (RIC) prior to allogeneic stem cell transplantation, to evaluate the safety and feasibility of Clostridium butyricum CBM 588 probiotic strain (CBM588) treatment by assessing:
Ia. Type, frequency, severity, attribution, time course and duration of adverse events, including diarrhea, bloodstream/intestinal infections.
Ib. Patient compliance, the patients' ability to take CBM588 during the treatment period.
SECONDARY OBJECTIVES:
I. Compare the incidence and severity of adverse events (AE) among CBM588-treated and untreated patients, including diarrhea, bloodstream infections and intestinal infections.
II. Estimate overall survival (OS), cumulative incidence (CI) of chronic graft versus host disease (GVHD), relapse/progression, and non-relapse mortality (NRM) at 100 days, 6 months, 1 year and 2 years.
EXPLORATORY OBJECTIVES:
I. Compare gut microbiome diversity among CBM588-treated/untreated patients. II. Obtain a preliminary estimate of the possible association between gut microbiome diversity and bloodstream infections.
III. Characterize and compare graft versus host disease (GVHD) inflammatory biomarkers (presence, level) among CBM588-treated and untreated patients.
IV. Obtain preliminary estimates of gut microbiome diversity, as assessed by the inverse Simpson Index, in CBM588-treated/untreated patients.
V. Obtain a preliminary estimate of the possible association between gut microbiome diversity and acute GVHD cumulative incidence, including time to onset.
VI. Characterize and compare urinary uindoxyl sulfate, tryptophan and kynurenine levels between CBM588- treated and untreated patients.
VII. To obtain a preliminary estimate of gut microbiome diversity and calorie intake.
VIII. Characterize and compare impact of CBM588 administration on regulatory T cells (T regs) reconstitution between CBM588-treated and untreated patients.
OUTLINE: Patients are randomized to 1 of 2 arms.
ARM I (CBM588): Patients receive standard peri-/post-transplant supportive care and CBM588 orally (PO) twice daily (BID) from day of admission to day 28 in the absence of disease progression or unacceptable toxicity.
ARM II (STANDARD OF CARE): Patients receive standard peri-/post-transplant supportive care.
After completion of study treatment, patients are followed up for 100 days and then up to 2 years.
1,464 studies on the registry are indexed under Hematologic Neoplasms; 433 are open to participants now.
This study's enrollment of 36 is below the median of 45 across 1,068 interventional studies indexed under Hematologic Neoplasms.
Browse Hematologic Neoplasms studies →City of Hope Medical Center is the lead sponsor of 670 studies on the registry; 181 are open to participants now.
Of its 30 completed or terminated interventional studies of FDA-regulated products, 12 (40%) have results posted.
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Documented informed consent of the participant and/or legally authorized representative.
Agreement by females and males of childbearing potential to use an effective method of birth control or abstain from heterosexual activity for the course of the study through at least 3 months after the last dose of protocol therapy.
Exclusion Criteria:
Known or documented history of hypersensitivity to all the listed antibiotics, used for severe infections related to CBM588:
Patients receive standard peri-/post-transplant supportive care and CBM588 PO BID from day of admission to day 28 in the absence of disease progression or unacceptable toxicity.
Other: Best Practice · Drug: Clostridium butyricum CBM 588 Probiotic Strain
Patients receive standard peri-/post-transplant supportive care.
Other: Best Practice
Receive standard peri-/post-transplant supportive care
Also known as: standard of care, standard therapy
Given PO
Also known as: C. butyricum CBM 588 Probiotic Strain, C. butyricum MIYAIRI Strain, C. butyricum Strain MIYAIRI 588, CBM 588, CBM588, Clostridium butyricum MIYAIRI 588, Clostridium butyricum MIYAIRI 588 Probiotic Strain, MIYAIRI 588, MIYAIRI 588 Strain of C. butyricum
Incidence of adverse events
Will be scored according to the modified Bearman Scale and National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE) version 5 scale. Observed toxicities will be summarized in terms of type (organ affected or laboratory determination), severity, time of onset, duration, probable association with the study treatment and reversibility or outcome.
Time frame: From initiation of treatment until end of treatment assessed up to 100 days
Feasibility of CBM588
Will be evaluated by assessment of patients' ability to take half of the specified dose.
Time frame: During the safety lead-in phase
Incidence and severity of adverse events
Assessed by modified Bearman criteria and NCI CTCAE version 5 scale. Will be compared among CBM588 treated and untreated patients.
Time frame: Up to 2 years
Overall survival
Will be estimated using the product-limit method of Kaplan and Meier.
Time frame: Up to 2 years
Cumulative incidence (CI) of chronic graft versus host disease (cGVHD)
Will be estimated using the method described by Gooley et al (1999).
Time frame: Up to 2 years
CI of acute graft versus host disease (aGVHD)
Will be estimated using the method described by Gooley et al (1999).
Time frame: Up to 2 years
CI of relapse/progression of disease
Will be estimated using the method described by Gooley et al (1999).
Time frame: Up to 2 years
Non-relapse mortality
Will be estimated using the method described by Gooley et al (1999).
Time frame: Up to 2 years
Gut microbiome diversity
Will be assessed by the inverse Simpson index. Will be compared among CBM588-treated/untreated patients and assessed by Fisher's exact test or two-sample Wilcoxon test whenever appropriate.
Time frame: Up to 2 years
Gut microbiome diversity and bloodstream infection
Incidence of bloodstream infections and infectious enterocolitis will be evaluated and a preliminary estimate of the association between gut microbiome diversity and blood stream infections will be obtained.
Time frame: Up to 2 years
Gut microbiome diversity aGVHD incidence
Will be obtained based on: 1) evaluation and comparison of presence and levels GVHD/inflammatory biomarkers including TNFR1, ST2, Reg3 alpha, TNF-alpha, IL-8 and TGF-beta 1 between the 2 study arms, and 2) incidence, site (gastrointestinal \[GI\], liver, and skin), severity (grade III-IV GI toxicity per the NCI CTCAE version 5 Scale) and time to onset of aGVHD among treated and untreated patients.
Time frame: Up to 2 years
Levels of tryptophan metabolites
Presence and levels of urinary uindoxyl sulfate, tryptophan and kynurenine (markers of GI GVHD complications) will be evaluated and compared between CBM588-treated and untreated patients.
Time frame: Up to 2 years
Impact on regulatory T cells (T regs)
Presence and levels T regs will be evaluated and compared in blood samples from patients among treated and untreated patients.
Time frame: Up to 2 years
This study is active, not recruiting, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
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