A Multiple Dose Study to Evaluate Safety, Tolerability, PK, and Efficacy of SER-155 in Adults Undergoing HSCT
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ClinicalTrials.gov Identifier: NCT04995653 |
Recruitment Status :
Recruiting
First Posted : August 9, 2021
Last Update Posted : November 10, 2022
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Allogeneic Hematopoietic Stem Cell Transplantation | Drug: Vancomycin Pre-Treatment Drug: Vancomycin Placebo Drug: SER-155 Drug: SER-155 Placebo | Phase 1 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 75 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Intervention Model Description: | There are 2 parts or cohorts for the trial. Cohort 1 is an open-label study. Cohort 2 is double-blind, randomized, placebo-controlled study. |
Masking: | Double (Participant, Investigator) |
Primary Purpose: | Treatment |
Official Title: | A Phase 1b Study to Evaluate Safety, Tolerability, Pharmacokinetics, and Efficacy of SER-155 in Adults Undergoing Hematopoietic Stem Cell Transplantation (HSCT) to Reduce the Risk of Infection and Graft vs. Host Disease (GvHD) |
Actual Study Start Date : | November 24, 2021 |
Estimated Primary Completion Date : | May 2025 |
Estimated Study Completion Date : | May 2025 |

Arm | Intervention/treatment |
---|---|
Experimental: Cohort 1 - Open Label Study
Vancomycin & SER-155
|
Drug: Vancomycin Pre-Treatment
Four times daily dosing with Vancomycin Drug: SER-155 Once daily dosing with SER-155 |
Experimental: Cohort 2 - Randomized, Double-Blind, Placebo-Controlled Study
Vancomycin & SER-155 OR Vancomycin placebo & SER-155 placebo
|
Drug: Vancomycin Pre-Treatment
Four times daily dosing with Vancomycin Drug: Vancomycin Placebo Four times daily dosing with Vancomycin Placebo Drug: SER-155 Once daily dosing with SER-155 Drug: SER-155 Placebo Once daily dosing with SER-155 placebo |
- Safety and tolerability of SER-155, including incidence and severity of adverse events, serious adverse events, or adverse events of special interest [ Time Frame: Day 100 ]Incidence and severity of participants with adverse events, serious adverse events, or adverse events of special interest
- Engraftment of SER-155 [ Time Frame: Day 100 ]Prevalence of SER-155 strains in subject stool measured before and after treatment courses
- Abundance of Enterococcus and Enterobacteriaceae [ Time Frame: Day 100 ]
- Combined and individual incidence of bloodstream infections, gastrointestinal infections, and acute Graft-versus Host Disease [ Time Frame: Day 100 ]
- Incidence and duration of febrile neutropenia [ Time Frame: Day 100 ]

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Male and female subjects ≥ 18 years of age undergoing HSCT.
- Planning to undergo allogeneic hematopoietic stem cell transplantation from a human leukocyte antigen matched sibling, haploidentical related donor, HLA-matched unrelated donor, or HLA 1-antigen mismatched unrelated donor, with either bone marrow or peripheral blood stem cells as a graft source, and with any conditioning regimen
Exclusion Criteria:
- Severe colitis of any etiology or active/currently-treated inflammatory bowel disease (IBD) or total colectomy.
- Evidence of relapse or progression of hematologic malignancy (minimal residual disease is allowed).
- Transplant using umbilical cord blood or ex vivo T-cell-depleted HSCT
- Receipt of chimeric antigen receptor T-cell (CAR-T) therapy.
- Received a fecal microbiota transplant (FMT) or any live microbial therapeutic within 3 months prior to Screening.
- Known allergy or intolerance to oral vancomycin.
- Concomitant participation or participation within 14 days or 5 half-lives of another investigational unapproved treatment, whichever is longer.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04995653
Contact: Bina Tejura, MD | 617-945-9626 | clinicalstudies@serestherapeutics.com |
United States, Arizona | |
Mayo Clinic - Scottsdale | Recruiting |
Scottsdale, Arizona, United States, 85259 | |
Contact: Nandita Khera, MD | |
United States, Florida | |
University of Florida - Division of Hematology & Oncology | Not yet recruiting |
Gainesville, Florida, United States, 32610 | |
Contact: Nosha Farhadfar, MD | |
Mayo Clinic - Jacksonville | Not yet recruiting |
Jacksonville, Florida, United States, 32224 | |
Contact: Hemant Murthy, MD | |
United States, Illinois | |
University of Chicago Medical Center | Recruiting |
Chicago, Illinois, United States, 60637 | |
Contact: Satyajit Kosuri, MD | |
United States, Massachusetts | |
Harvard Medical School - Massachusetts General Hospital Cancer Center | Recruiting |
Boston, Massachusetts, United States, 02114 | |
Contact: Zachariah DeFilipp, MD | |
United States, New York | |
Memorial Sloan Kettering Cancer Center | Recruiting |
New York, New York, United States, 10065 | |
Contact: Doris Ponce, MD | |
United States, Washington | |
Fred Hutchinson Cancer Research Center | Not yet recruiting |
Seattle, Washington, United States, 98109 | |
Contact: David Fredricks, MD |
Principal Investigator: | Doris Ponce, MD | MSKCC | |
Study Director: | Bina Tejura, MD | Seres Therapeutics, Inc. |
Responsible Party: | Seres Therapeutics, Inc. |
ClinicalTrials.gov Identifier: | NCT04995653 |
Other Study ID Numbers: |
SER-155-001 |
First Posted: | August 9, 2021 Key Record Dates |
Last Update Posted: | November 10, 2022 |
Last Verified: | November 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Microbiome stem cell transplant |
Vancomycin Anti-Bacterial Agents Anti-Infective Agents |