A Phase 3 interventional study of RBX2660 in Clostridium Difficile Infection Recurrence, sponsored by Ferring Pharmaceuticals. Completed at 12 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-04-24.
Sponsored by Ferring Pharmaceuticals · Phase 3, Interventional, and Treatment
This trial will be initiated to explore whether RBX2660 (REBYOTA®) could be suitable for administration by the practice of colonoscopy. More specifically, the purpose of this trial is to explore the safety and clinical effectiveness of RBX2660 when delivered by colonoscopy to adults with rCDI. The experience of physicians will be documented through a physician-experience questionnaire to explore the usability of RBX2660 in clinical practice for colonoscopic administration. Furthermore, to explore the patient-experience of RBX2660 treatment, each trial participant will be offered to undergo a structured interview.
877 studies on the registry are indexed under Diarrhea; 76 are open to participants now.
This study's enrollment of 41 is below the median of 137 across 738 interventional studies indexed under Diarrhea.
Browse Diarrhea studies →Ferring Pharmaceuticals is the lead sponsor of 249 studies on the registry; 4 are open to participants now.
Of its 15 completed or terminated interventional studies of FDA-regulated products, 14 (93%) have results posted.
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Exclusion Criteria:
Drug: RBX2660
RBX2660 should be administered to the right side of the colon (i.e., between the ileocecal valve and the hepatic flexure of the colon).
Also known as: REBYOTA®
Number of Participants With RBX2660-related Treatment-emergent Adverse Events (TEAEs) After RBX2660 Treatment Delivered by Colonoscopy Through 8 Weeks, or Treatment Failure
Time frame: 8 weeks after RBX2660 treatment delivered by colonoscopy
Number of Participants With Recurrence of Clostridioides Difficile Infection (CDI) Within 8 Weeks After RBX2660 Treatment Delivered by Colonoscopy.
Time frame: Within 8 weeks after RBX2660 treatment delivered by colonoscopy
Time to CDI Recurrence From Baseline Through 8 Weeks After RBX2660 Treatment Delivered by Colonoscopy
Time frame: 8 weeks after RBX2660 treatment delivered by colonoscopy
Physician-experience, as Determined by Questionnaire, Documenting Subjective Experience of Investigators on Usability of RBX2660 in Clinical Practice When Delivered by Colonoscopy
Time frame: At Day 1 (baseline visit)
Physician Perception of Patient Benefit, as Determined by Number of Participants With Clinician Global Impression of Improvement (CGI-I) at 8 Weeks, or at Treatment Failure, After RBX2660 Treatment Delivered by Colonoscopy
Time frame: 8 weeks after RBX2660 treatment delivered by colonoscopy
Patient-experience Interview at 8 Weeks, or at Treatment Failure, After RBX2660 Treatment Delivered by Colonoscopy
Time frame: 8 weeks after RBX2660 treatment delivered by colonoscopy
Number of Participants With Treatment-emergent Adverse Events up to 8 Weeks or Treatment Failure After RBX2660 Treatment
Time frame: Up to 8 weeks after RBX2660 treatment delivered by colonoscopy
Number of Participants With Serious Adverse Events (SAEs)
Time frame: Up to 8 weeks after RBX2660 treatment delivered by colonoscopy
Number of Participants With Any Adverse Events of Special Interest (AESIs)
Time frame: Up to 8 weeks after RBX2660 treatment delivered by colonoscopy
Number of Participants With Adverse Events Leading to Death or Intensive Care Unit (ICU) Admission
Time frame: Up to 8 weeks after RBX2660 treatment delivered by colonoscopy
| Milestone | RBX2660 |
|---|---|
| Started | 41 |
| Completed | 39 |
| Not completed | 2 |
| Withdrew: Withdrawal by subject | 2 |
| Participants | RBX2660 |
|---|---|
| Number of Participants With RBX2660-related Treatment-emergent Adverse Events (TEAEs) After RBX2660 Treatment Delivered by Colonoscopy Through 8 Weeks, or Treatment Failure | 18 |
| Participants | RBX2660 |
|---|---|
| Number of Participants With Recurrence of Clostridioides Difficile Infection (CDI) Within 8 Weeks After RBX2660 Treatment Delivered by Colonoscopy. | 2 |
| Weeks | RBX2660 |
|---|---|
| Time to CDI Recurrence From Baseline Through 8 Weeks After RBX2660 Treatment Delivered by Colonoscopy | 0 |
| Participants | RBX2660 |
|---|---|
| Preparations before administration — Somewhat positive | 2 |
| Preparations before administration — Positive experience | 20 |
| Preparations before administration — Very positive experience | 19 |
| Preparations before administration — Somewhat negative experience | 0 |
| Preparations before administration — Neutral experience | 0 |
| Ease of administration — Somewhat positive | 0 |
| Ease of administration — Positive experience | 17 |
| Ease of administration — Very positive experience | 21 |
| Ease of administration — Somewhat negative experience | 1 |
| Ease of administration — Neutral experience | 2 |
| Activities following administration — Somewhat positive | 1 |
| Activities following administration — Positive experience | 16 |
| Activities following administration — Very positive experience | 21 |
| Activities following administration — Somewhat negative experience | 0 |
| Activities following administration — Neutral experience | 3 |
| Overall experience using RBX2660 — Somewhat positive | 1 |
| Overall experience using RBX2660 — Positive experience | 23 |
| Overall experience using RBX2660 — Very positive experience | 14 |
| Overall experience using RBX2660 — Somewhat negative experience | 1 |
| Overall experience using RBX2660 — Neutral experience | 2 |
| Participants | RBX2660 |
|---|---|
| Very much improved | 26 |
| Much improved | 13 |
| Participants | RBX2660 |
|---|---|
| Very Much Improved | 26 |
| Much Improved | 13 |
| Participants | RBX2660 |
|---|---|
| Adverse events | 18 |
| Mild adverse events | 14 |
| Moderate adverse events | 3 |
| Severe adverse events | 2 |
| Potentially Life-threatening | 1 |
| Adverse events leading to discontinuation | 0 |
| Serious adverse events | 2 |
| Adverse events leading to death | 0 |
| Participants | RBX2660 |
|---|---|
| Number of Participants With Serious Adverse Events (SAEs) | 2 |
| Participants | RBX2660 |
|---|---|
| Number of Participants With Any Adverse Events of Special Interest (AESIs) | 2 |
| Participants | RBX2660 |
|---|---|
| Number of Participants With Adverse Events Leading to Death or Intensive Care Unit (ICU) Admission | 2 |
Collected over 8 weeks. Non-serious events are listed at a 5% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| RBX2660 | 0/41 (0%) | 2/41 (4.9%) | 6/41 (14.6%) |
| Event | RBX2660 |
|---|---|
| Colitis UlcerativeGastrointestinal disorders | 1/41 |
| Brain NeoplasmNeoplasms benign, malignant and unspecified (incl cysts and polyps) | 1/41 |
| Event | RBX2660 |
|---|---|
| Abdominal DistensionGastrointestinal disorders | 3/41 |
| ConstipationGastrointestinal disorders | 3/41 |
| Age, Continuous(Years) | RBX2660 |
|---|---|
| Mean | 61.2 ± 14.9 |
| Sex: Female, Male(Participants) | RBX2660 |
|---|---|
| Female | 36 |
| Male | 5 |
| Ethnicity (NIH/OMB)(Participants) | RBX2660 |
|---|---|
| Hispanic or Latino | 1 |
| Not Hispanic or Latino | 40 |
| Unknown or Not Reported | 0 |
| Race (NIH/OMB)(Participants) | RBX2660 |
|---|---|
| American Indian or Alaska Native | 0 |
| Asian | 0 |
| Native Hawaiian or Other Pacific Islander | 0 |
| Black or African American | 2 |
| White | 39 |
| More than one race | 0 |
| Unknown or Not Reported | 0 |
| Number of Previous CDI Episodes(Episodes) | RBX2660 |
|---|---|
| Mean | 3.2 ± 1.8 |
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: No
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Studies of the drug tested here: RBX2660