Trial Outcomes & Findings for ICON-2: FMT and Bezlotoxumab Compared to FMT and Placebo for Patients With IBD and CDI (NCT NCT03829475)

NCT ID: NCT03829475

Last Updated: 2025-12-09

Results Overview

positive test for CDI by EIA toxin

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

61 participants

Primary outcome timeframe

8 weeks

Results posted on

2025-12-09

Participant Flow

Participant milestones

Participant milestones
Measure
FMT + Bezlo
Participants received an FMT via colonoscopy (250ml) as well as a single IV infusion of bezlotoxumab (10mg/kg) that took place over 60 minutes. Bezlotoxumab: This is a a fully human monoclonal antibody that binds to C. difficile toxin B, and is indicated to prevent recurrence of CDI in adults at risk for recurrent CDI (rCDI). Fecal Microbiota Transplantation: FMT is an infusion of prescreened donor stool that will be administered via colonoscopy
FMT + Placebo
Participants received a single FMT via colonoscopy (250ml) and a placebo (saline) infusion (250cc) over 60 minutes. Placebo: placebo is an infusion of normal saline. Fecal Microbiota Transplantation: FMT is an infusion of prescreened donor stool that will be administered via colonoscopy
Overall Study
STARTED
30
31
Overall Study
COMPLETED
30
31
Overall Study
NOT COMPLETED
0
0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Partial Mayo only applies to subjects with Ulcerative Colitis

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
FMT + Bezlo
n=30 Participants
Participants received an FMT via colonoscopy (250ml) as well as a single IV infusion of bezlotoxumab (10mg/kg) that took place over 60 minutes. Bezlotoxumab: This is a a fully human monoclonal antibody that binds to C. difficile toxin B, and is indicated to prevent recurrence of CDI in adults at risk for recurrent CDI (rCDI). Fecal Microbiota Transplantation: FMT is an infusion of prescreened donor stool that will be administered via colonoscopy
FMT + Placebo
n=31 Participants
Participants received a single FMT via colonoscopy (250ml) and a placebo (saline) infusion (250cc) over 60 minutes. Placebo: placebo is an infusion of normal saline. Fecal Microbiota Transplantation: FMT is an infusion of prescreened donor stool that will be administered via colonoscopy
Total
n=61 Participants
Total of all reporting groups
Age, Continuous
38.5 years
n=30 Participants
34 years
n=31 Participants
38 years
n=61 Participants
Sex: Female, Male
Female
14 Participants
n=30 Participants
14 Participants
n=31 Participants
28 Participants
n=61 Participants
Sex: Female, Male
Male
16 Participants
n=30 Participants
17 Participants
n=31 Participants
33 Participants
n=61 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
n=30 Participants
0 Participants
n=31 Participants
0 Participants
n=61 Participants
Race (NIH/OMB)
Asian
0 Participants
n=30 Participants
1 Participants
n=31 Participants
1 Participants
n=61 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=30 Participants
0 Participants
n=31 Participants
0 Participants
n=61 Participants
Race (NIH/OMB)
Black or African American
2 Participants
n=30 Participants
1 Participants
n=31 Participants
3 Participants
n=61 Participants
Race (NIH/OMB)
White
27 Participants
n=30 Participants
27 Participants
n=31 Participants
54 Participants
n=61 Participants
Race (NIH/OMB)
More than one race
0 Participants
n=30 Participants
0 Participants
n=31 Participants
0 Participants
n=61 Participants
Race (NIH/OMB)
Unknown or Not Reported
1 Participants
n=30 Participants
2 Participants
n=31 Participants
3 Participants
n=61 Participants
Baseline Calprotectin
930.5 mcg/g
n=30 Participants
241 mcg/g
n=31 Participants
635 mcg/g
n=61 Participants
Baseline Bowel Movement
5 bowel movements
n=30 Participants
4 bowel movements
n=31 Participants
5 bowel movements
n=61 Participants
Baseline Bristol Score
5 units on a scale
n=30 Participants
5 units on a scale
n=31 Participants
5 units on a scale
n=61 Participants
Baseline Partial Mayo
3.5 units on a scale
n=24 Participants • Partial Mayo only applies to subjects with Ulcerative Colitis
2 units on a scale
n=17 Participants • Partial Mayo only applies to subjects with Ulcerative Colitis
3 units on a scale
n=41 Participants • Partial Mayo only applies to subjects with Ulcerative Colitis
Baseline Harvey Bradshaw Index
7 units on a scale
n=6 Participants • HBI only applies to subjects with Crohn's Disease
6.5 units on a scale
n=14 Participants • HBI only applies to subjects with Crohn's Disease
6.5 units on a scale
n=20 Participants • HBI only applies to subjects with Crohn's Disease

PRIMARY outcome

Timeframe: 8 weeks

positive test for CDI by EIA toxin

Outcome measures

Outcome measures
Measure
FMT + Bezlo
n=30 Participants
Participants received an FMT via colonoscopy (250ml) as well as a single IV infusion of bezlotoxumab (10mg/kg) that took place over 60 minutes. Bezlotoxumab: This is a a fully human monoclonal antibody that binds to C. difficile toxin B, and is indicated to prevent recurrence of CDI in adults at risk for recurrent CDI (rCDI). Fecal Microbiota Transplantation: FMT is an infusion of prescreened donor stool that will be administered via colonoscopy
FMT + Placebo
n=31 Participants
Participants received a single FMT via colonoscopy (250ml) and a placebo (saline) infusion (250cc) over 60 minutes. Placebo: placebo is an infusion of normal saline. Fecal Microbiota Transplantation: FMT is an infusion of prescreened donor stool that will be administered via colonoscopy
Number of Participants With Clostridium Difficile Recurrence
4 Participants
1 Participants

Adverse Events

FMT + Bezlo

Serious events: 5 serious events
Other events: 16 other events
Deaths: 0 deaths

FMT + Placebo

Serious events: 4 serious events
Other events: 15 other events
Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure
FMT + Bezlo
n=30 participants at risk
Participants received an FMT via colonoscopy (250ml) as well as a single IV infusion of bezlotoxumab (10mg/kg) that took place over 60 minutes. Bezlotoxumab: This is a a fully human monoclonal antibody that binds to C. difficile toxin B, and is indicated to prevent recurrence of CDI in adults at risk for recurrent CDI (rCDI). Fecal Microbiota Transplantation: FMT is an infusion of prescreened donor stool that will be administered via colonoscopy
FMT + Placebo
n=31 participants at risk
Participants received a single FMT via colonoscopy (250ml) and a placebo (saline) infusion (250cc) over 60 minutes. Placebo: placebo is an infusion of normal saline. Fecal Microbiota Transplantation: FMT is an infusion of prescreened donor stool that will be administered via colonoscopy
Gastrointestinal disorders
IBD Flare
3.3%
1/30 • Number of events 1 • Adverse event data was collected through Week 26 (6 months).
0.00%
0/31 • Adverse event data was collected through Week 26 (6 months).
Gastrointestinal disorders
Colectomy
3.3%
1/30 • Number of events 1 • Adverse event data was collected through Week 26 (6 months).
0.00%
0/31 • Adverse event data was collected through Week 26 (6 months).
Gastrointestinal disorders
Hospitalization
3.3%
1/30 • Number of events 1 • Adverse event data was collected through Week 26 (6 months).
0.00%
0/31 • Adverse event data was collected through Week 26 (6 months).
Gastrointestinal disorders
IBD flare
3.3%
1/30 • Number of events 1 • Adverse event data was collected through Week 26 (6 months).
0.00%
0/31 • Adverse event data was collected through Week 26 (6 months).

Other adverse events

Other adverse events
Measure
FMT + Bezlo
n=30 participants at risk
Participants received an FMT via colonoscopy (250ml) as well as a single IV infusion of bezlotoxumab (10mg/kg) that took place over 60 minutes. Bezlotoxumab: This is a a fully human monoclonal antibody that binds to C. difficile toxin B, and is indicated to prevent recurrence of CDI in adults at risk for recurrent CDI (rCDI). Fecal Microbiota Transplantation: FMT is an infusion of prescreened donor stool that will be administered via colonoscopy
FMT + Placebo
n=31 participants at risk
Participants received a single FMT via colonoscopy (250ml) and a placebo (saline) infusion (250cc) over 60 minutes. Placebo: placebo is an infusion of normal saline. Fecal Microbiota Transplantation: FMT is an infusion of prescreened donor stool that will be administered via colonoscopy
Gastrointestinal disorders
Fecal urgency
3.3%
1/30 • Adverse event data was collected through Week 26 (6 months).
0.00%
0/31 • Adverse event data was collected through Week 26 (6 months).
Gastrointestinal disorders
Flatulence
3.3%
1/30 • Adverse event data was collected through Week 26 (6 months).
3.2%
1/31 • Adverse event data was collected through Week 26 (6 months).
Metabolism and nutrition disorders
Anorexia
3.3%
1/30 • Adverse event data was collected through Week 26 (6 months).
0.00%
0/31 • Adverse event data was collected through Week 26 (6 months).
Injury, poisoning and procedural complications
Dermatitis Radiation
3.3%
1/30 • Adverse event data was collected through Week 26 (6 months).
0.00%
0/31 • Adverse event data was collected through Week 26 (6 months).
Renal and urinary disorders
Urinary incontinence
3.3%
1/30 • Adverse event data was collected through Week 26 (6 months).
0.00%
0/31 • Adverse event data was collected through Week 26 (6 months).
Infections and infestations
Herpes Simplex Reactivation
0.00%
0/30 • Adverse event data was collected through Week 26 (6 months).
3.2%
1/31 • Adverse event data was collected through Week 26 (6 months).
Vascular disorders
Flushing
0.00%
0/30 • Adverse event data was collected through Week 26 (6 months).
3.2%
1/31 • Adverse event data was collected through Week 26 (6 months).
Gastrointestinal disorders
Bloating
0.00%
0/30 • Adverse event data was collected through Week 26 (6 months).
3.2%
1/31 • Adverse event data was collected through Week 26 (6 months).
Immune system disorders
Allergic reaction
3.3%
1/30 • Adverse event data was collected through Week 26 (6 months).
0.00%
0/31 • Adverse event data was collected through Week 26 (6 months).
Vascular disorders
Thrombocytopenia
0.00%
0/30 • Adverse event data was collected through Week 26 (6 months).
3.2%
1/31 • Adverse event data was collected through Week 26 (6 months).
General disorders
COVID-19 Infection
3.3%
1/30 • Adverse event data was collected through Week 26 (6 months).
0.00%
0/31 • Adverse event data was collected through Week 26 (6 months).
Gastrointestinal disorders
Diarrhea
26.7%
8/30 • Adverse event data was collected through Week 26 (6 months).
22.6%
7/31 • Adverse event data was collected through Week 26 (6 months).
Gastrointestinal disorders
Rectal Bleeding
3.3%
1/30 • Adverse event data was collected through Week 26 (6 months).
0.00%
0/31 • Adverse event data was collected through Week 26 (6 months).
Gastrointestinal disorders
Abdominal Pain
23.3%
7/30 • Adverse event data was collected through Week 26 (6 months).
19.4%
6/31 • Adverse event data was collected through Week 26 (6 months).
Gastrointestinal disorders
Nausea
0.00%
0/30 • Adverse event data was collected through Week 26 (6 months).
3.2%
1/31 • Adverse event data was collected through Week 26 (6 months).
Gastrointestinal disorders
Vomiting
0.00%
0/30 • Adverse event data was collected through Week 26 (6 months).
6.5%
2/31 • Adverse event data was collected through Week 26 (6 months).
Gastrointestinal disorders
Constipation
0.00%
0/30 • Adverse event data was collected through Week 26 (6 months).
3.2%
1/31 • Adverse event data was collected through Week 26 (6 months).
Skin and subcutaneous tissue disorders
Chest Rash
0.00%
0/30 • Adverse event data was collected through Week 26 (6 months).
3.2%
1/31 • Adverse event data was collected through Week 26 (6 months).
General disorders
Fatigue
6.7%
2/30 • Adverse event data was collected through Week 26 (6 months).
3.2%
1/31 • Adverse event data was collected through Week 26 (6 months).
General disorders
Headache
3.3%
1/30 • Adverse event data was collected through Week 26 (6 months).
3.2%
1/31 • Adverse event data was collected through Week 26 (6 months).
General disorders
Fever
3.3%
1/30 • Adverse event data was collected through Week 26 (6 months).
3.2%
1/31 • Adverse event data was collected through Week 26 (6 months).

Additional Information

Jessica Allegretti MD MPH

Brigham and Women's Hospital

Phone: 617-525-7322

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place