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Rifaximin for the Treatment of Gastrointestinal Toxicities Related to Pertuzumab-Based Therapy in Patients With Stage I-III HER2 Positive Breast Cancer

Phase II Trial of Rifaximin in Patients With Early Stage HER2 Positive Breast Cancer With Gastrointestinal Toxicities Related to Pertuzumab-Based Therapy

Status
Terminated
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04249622
Enrollment
20
Registered
2020-01-31
Start date
2020-09-18
Completion date
2022-12-27
Last updated
2025-09-16

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Anatomic Stage IA Breast Cancer AJCC v8, Anatomic Stage IB Breast Cancer AJCC v8, Anatomic Stage I Breast Cancer AJCC v8, Anatomic Stage IIA Breast Cancer AJCC v8, Anatomic Stage IIB Breast Cancer AJCC v8, Anatomic Stage II Breast Cancer AJCC v8, Anatomic Stage IIIA Breast Cancer AJCC v8, Anatomic Stage IIIB Breast Cancer AJCC v8, Anatomic Stage III Breast Cancer AJCC v8, Anatomic Stage IIIC Breast Cancer AJCC v8, HER2 Positive Breast Carcinoma, Prognostic Stage IA Breast Cancer AJCC v8, Prognostic Stage IB Breast Cancer AJCC v8, Prognostic Stage I Breast Cancer AJCC v8, Prognostic Stage IIA Breast Cancer AJCC v8, Prognostic Stage IIB Breast Cancer AJCC v8, Prognostic Stage II Breast Cancer AJCC v8, Prognostic Stage IIIA Breast Cancer AJCC v8, Prognostic Stage IIIB Breast Cancer AJCC v8, Prognostic Stage III Breast Cancer AJCC v8, Prognostic Stage IIIC Breast Cancer AJCC v8

Brief summary

This phase II trial studies how well rifaximin works for the treatment of gastrointestinal toxicities related to pertuzumab-based therapy in patients with stage I-III HER2 positive breast cancer. Rifaximin may reduce the incidence and severity of pertuzumab induced gastrointestinal toxicities without interrupting or delaying the chemotherapy schedule.

Detailed description

PRIMARY OBJECTIVE: I. To evaluate the reduction rate of grade \>= 2 abdominal toxicities, including abdominal distension, abdominal pain, diarrhea, dyspepsia, stomach pain, and typhlitis according to the National Cancer Institute Common Terminology for Adverse Events version 5.0 (NCI CTCAE v5.0) with the use of rifaximin in stage II-III HER-2 positive breast cancer patients with pertuzumab induced gastrointestinal toxicities. SECONDARY OBJECTIVES: I. Evaluate dose reductions, dose delays and discontinuation of treatment with pertuzumab due to gastrointestinal side effects. II. Evaluate and measure the change in the Bristol stool scale before and after rifaximin treatment. III. Evaluate and measure the change in the 4-point Likert scale patient questionnaire before and after rifaximin treatment. CORRELATIVE STUDY OBJECTIVES: I. Evaluate changes in the fecal microbiome, hydrogen breath test, and permeability test before and after rifaximin. II. Evaluate changes in the fecal microbiome, hydrogen breath test, and permeability test before and after pertuzumab-based chemotherapy. III. Evaluate the difference in the fecal microbiome, hydrogen breath test, and permeability test among patients with or without pertuzumab induced gastrointestinal toxicities (PIGT). OUTLINE: Patients are assigned to 1 of 2 arms. ARM I (GRADE \>= 2 PIGT): Patients that experience PIGT after receiving first standard of care cycle of pertuzumab-based chemotherapy receive rifaximin orally (PO) twice daily (BID) on days 1-5 and standard of care pertuzumab-based chemotherapy on day 1. Treatment repeats every 21 days for up to 5 cycles in the absence of disease progression or unacceptable toxicity. ARM II (GRADE =\< 1 PIGT): Patients that do not experience PIGT after receiving first standard of care cycle of pertuzumab-based chemotherapy continue receiving standard of care pertuzumab-based chemotherapy on day 1. Treatment repeats every 21 days for up to 5 cycles in the absence of disease progression or unacceptable toxicity.

Interventions

OTHERBest Practice

Given standard of care pertuzumab-based chemotherapy

OTHERQuestionnaire Administration

Ancillary studies

DRUGRifaximin

Given PO

Sponsors

Mayo Clinic
Lead SponsorOTHER

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* PRE-REGISTRATION INCLUSION CRITERIA * Age \>= 18 years * Histological confirmation of HER2 positive breast cancer stage I-III per American Joint Committee on Cancer (AJCC) staging 8th edition * Provide written informed consent * Breast cancer patients who will be receiving pertuzumab-based chemotherapy with either TCHP (docetaxel, carboplatin, trastuzumab, and pertuzumab) or docetaxel/paclitaxel, trastuzumab, and pertuzumab * Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0, 1, or 2 * Hemoglobin \>= 10.0 g/dL (obtained =\< 30 days prior to pre-registration) * Absolute neutrophil count (ANC) \>= 1.5 x 10\^9/L (obtained =\< 30 days prior to pre-registration) * Platelet count \>= 100 x 10\^9/L (obtained =\< 30 days prior to pre-registration) * Total bilirubin =\< 1.5 x ULN (institutional upper limit of normal) (obtained =\< 30 days prior to pre-registration) * Aspartate aminotransferase (AST) (serum glutamic-oxaloacetic transaminase \[SGOT\])/alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase \[SGPT\]) =\< 2.5 x ULN (obtained =\< 30 days prior to pre-registration) * Serum or plasma creatinine =\< 1.5 x ULN (obtained =\< 30 days prior to pre-registration) * Calculated creatinine clearance \>= 45 ml/min using the Cockcroft-Gault formula (obtained =\< 30 days prior to pre-registration) * Negative serum pregnancy test done =\< 30 days prior to pre-registration, for person of childbearing potential only * Willingness to return to enrolling institution for follow-up (during the active monitoring phase of the study) * Willingness to provide mandatory stool specimen for correlative research * Ability to complete questionnaire(s) by themselves or with assistance * REGISTRATION INCLUSION CRITERIA * Received pertuzumab based regimens in the adjuvant or neoadjuvant setting * Hemoglobin \>= 8.0 g/dL (obtained =\< 14 days prior to registration) * Absolute neutrophil count (ANC) \>= 1.5 x 10\^9/L (obtained =\< 14 days prior to registration) * Platelet count \>= 100 x 10\^9/L (obtained =\< 14 days prior to registration) * Total bilirubin =\< 1.5 x ULN (institutional upper limit of normal) (obtained =\< 14 days prior to registration) * AST (SGOT)/ALT (SGPT) =\< 2.5 x ULN (obtained =\< 14 days prior to registration) * Serum or plasma creatinine =\< 1.5 x ULN (obtained =\< 14 days prior to registration) * Calculated creatinine clearance \>= 45 ml/min using the Cockcroft-Gault formula (obtained =\< 14 days prior to registration)

Exclusion criteria

* PRE-REGISTRATION

Design outcomes

Primary

MeasureTime frameDescription
Reduction Rate of >= Grade 2 Abdominal Toxicities Including Abdominal Distension, Abdominal Pain, Diarrhea, Dyspepsia, Stomach Pain, and TyphlitisThrough study completion (approximately 2 years, 3 months)Based on the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. The proportion of successes will be estimated by the number of successes divided by the total number of evaluable patients. Confidence intervals for the true success proportion will be calculated according to the approach of Duffy and Santner (1987).

Secondary

MeasureTime frameDescription
Dose Delays of Treatment With PertuzumabUp to 3 yearsNumber of patients that experienced a dose delay with pertuzumab due to gastrointestinal side effects.
Discontinuation of Treatment With PertuzumabUp to 3 yearsThe number of patients that experienced discontinuation of treatment with pertuzumab due to gastrointestinal side effects.
Number of Patient With a Reduction of Mean Number of StoolsUp to 3 yearsNumber of patients that experienced a reduction of mean number of stools recorded while on treatment compared to baseline will be reported
Average Maximum Pertuzumab Induced Gastrointestinal Toxicities (PIGT) ScoreBaseline (at enrollment); following each treatment cycle (21 days +/- 7 days), up to 5 cyclesMaximum PIGT score represents the maximum grade of adverse event experienced by a patient out of all gastrointestinal adverse events. PIGT scores are assessed according to NCI CTCAE v5.0, with a minimum grade of 0 (no event) and maximum grade of 5 (death).
Dose Reductions of Treatment With PertuzumabUp to 3 yearsNumber of patients that experienced a dose reductions with pertuzumab due to gastrointestinal side effects.

Other

MeasureTime frameDescription
Difference in the Fecal Microbiome, Hydrogen Breath Test, and Permeability TestUp to 3 yearsDescriptive statistics (mean, sd, median, iqr) and longitudinal plots (raw value, change, change in percentage) will be used to the fecal microbiome, hydrogen breath test, and permeability test among patients with or without PIGT. The study is not powered to detect any differences between the two arms; the main purpose is to quantify and evaluate differences descriptively between patients who develop and do not develop PIGT (between arm 1 and arm 2) to inform subsequent research.
Changes in the Fecal Microbiome, Hydrogen Breath Test, and Permeability Test - PertuzumabBaseline up to 3 yearsDescriptive statistics (mean, sd, median, iqr) and longitudinal plots (raw value, change, change in percentage) will be used to summarize the baseline levels of hydrogen/methane peak by hydrogen breath test, diversity of gut microbiome (number of species) and specific species by fecal microbiome, and levels of urine mannitol and lactulose by permeability test before and after pertuzumab-based chemotherapy.
Changes in the Fecal Microbiome, Hydrogen Breath Test, and Permeability Test - RifaximinBaseline up to 3 yearsDescriptive statistics (mean, standard deviation \[sd\], median, interquartile range \[iqr\]) and longitudinal plots (raw value, change, change in percentage) will be used to summarize the baseline levels of hydrogen/methane peak by hydrogen breath test , diversity of gut microbiome(number of species) and specific species by fecal microbiome, and levels of urine mannitol and lactulose by permeability test before and after rifaximin.

Countries

United States

Participant flow

Participants by arm

ArmCount
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)
Patients that experience PIGT after receiving first standard of care cycle of pertuzumab-based chemotherapy receive rifaximin PO BID on days 1-5 and standard of care pertuzumab-based chemotherapy on day 1. Treatment repeats every 21 days for up to 5 cycles in the absence of disease progression or unacceptable toxicity.\> * Best Practice: Given standard of care pertuzumab-based chemotherapy \> * Questionnaire Administration: Ancillary studies \> * Rifaximin: Given PO
18
Arm II (Pertuzumab-based Chemotherapy)
Patients that do not experience PIGT after receiving first standard of care cycle of pertuzumab-based chemotherapy continue receiving standard of care pertuzumab-based chemotherapy on day 1. Treatment repeats every 21 days for up to 5 cycles in the absence of disease progression or unacceptable toxicity.\> * Best Practice: Given standard of care pertuzumab-based chemotherapy\> * Questionnaire Administration: Ancillary studies
2
Total20

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyAlternative therapy10
Overall StudyDiscontinuation of pertuzumab10
Overall StudyWithdrawal by Subject11

Baseline characteristics

CharacteristicTotalArm I (Rifaximin, Pertuzumab-based Chemotherapy)Arm II (Pertuzumab-based Chemotherapy)
Age, Continuous53.9 years
STANDARD_DEVIATION 9.35
53.8 years
STANDARD_DEVIATION 9.72
55.0 years
STANDARD_DEVIATION 7.07
ECOG Performance Status
0
18 Participants16 Participants2 Participants
ECOG Performance Status
1
2 Participants2 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
1 Participants1 Participants0 Participants
Race (NIH/OMB)
Black or African American
1 Participants1 Participants0 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
18 Participants16 Participants2 Participants
Region of Enrollment
United States
20 participants18 participants2 participants
Sex: Female, Male
Female
20 Participants18 Participants2 Participants
Sex: Female, Male
Male
0 Participants0 Participants0 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 180 / 2
other
Total, other adverse events
18 / 182 / 2
serious
Total, serious adverse events
1 / 180 / 2

Outcome results

Primary

Reduction Rate of >= Grade 2 Abdominal Toxicities Including Abdominal Distension, Abdominal Pain, Diarrhea, Dyspepsia, Stomach Pain, and Typhlitis

Based on the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. The proportion of successes will be estimated by the number of successes divided by the total number of evaluable patients. Confidence intervals for the true success proportion will be calculated according to the approach of Duffy and Santner (1987).

Time frame: Through study completion (approximately 2 years, 3 months)

Population: Only patients that received rifaximin were included in analysis

ArmMeasureValue (NUMBER)
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)Reduction Rate of >= Grade 2 Abdominal Toxicities Including Abdominal Distension, Abdominal Pain, Diarrhea, Dyspepsia, Stomach Pain, and Typhlitis0.833 proportion of participants
Secondary

Average Maximum Pertuzumab Induced Gastrointestinal Toxicities (PIGT) Score

Maximum PIGT score represents the maximum grade of adverse event experienced by a patient out of all gastrointestinal adverse events. PIGT scores are assessed according to NCI CTCAE v5.0, with a minimum grade of 0 (no event) and maximum grade of 5 (death).

Time frame: Baseline (at enrollment); following each treatment cycle (21 days +/- 7 days), up to 5 cycles

Population: Only patients in arm 1 were included in analysis. Patients in arm 2 did not experience PIGT. Only patients still on treatment were included in each cycle's analysis.

ArmMeasureGroupValue (MEAN)Dispersion
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)Average Maximum Pertuzumab Induced Gastrointestinal Toxicities (PIGT) ScoreBaseline2.17 units on a scaleStandard Deviation 0.38
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)Average Maximum Pertuzumab Induced Gastrointestinal Toxicities (PIGT) ScoreCycle 11.61 units on a scaleStandard Deviation 0.78
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)Average Maximum Pertuzumab Induced Gastrointestinal Toxicities (PIGT) ScoreCycle 21.83 units on a scaleStandard Deviation 0.79
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)Average Maximum Pertuzumab Induced Gastrointestinal Toxicities (PIGT) ScoreCycle 31.71 units on a scaleStandard Deviation 0.85
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)Average Maximum Pertuzumab Induced Gastrointestinal Toxicities (PIGT) ScoreCycle 41.5 units on a scaleStandard Deviation 0.73
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)Average Maximum Pertuzumab Induced Gastrointestinal Toxicities (PIGT) ScoreCycle 51.53 units on a scaleStandard Deviation 0.74
Secondary

Discontinuation of Treatment With Pertuzumab

The number of patients that experienced discontinuation of treatment with pertuzumab due to gastrointestinal side effects.

Time frame: Up to 3 years

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)Discontinuation of Treatment With Pertuzumab0 Participants
Arm II (Pertuzumab-based Chemotherapy)Discontinuation of Treatment With Pertuzumab0 Participants
Secondary

Dose Delays of Treatment With Pertuzumab

Number of patients that experienced a dose delay with pertuzumab due to gastrointestinal side effects.

Time frame: Up to 3 years

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)Dose Delays of Treatment With Pertuzumab1 Participants
Arm II (Pertuzumab-based Chemotherapy)Dose Delays of Treatment With Pertuzumab0 Participants
Secondary

Dose Reductions of Treatment With Pertuzumab

Number of patients that experienced a dose reductions with pertuzumab due to gastrointestinal side effects.

Time frame: Up to 3 years

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)Dose Reductions of Treatment With Pertuzumab10 Participants
Arm II (Pertuzumab-based Chemotherapy)Dose Reductions of Treatment With Pertuzumab0 Participants
Secondary

Number of Patient With a Reduction of Mean Number of Stools

Number of patients that experienced a reduction of mean number of stools recorded while on treatment compared to baseline will be reported

Time frame: Up to 3 years

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Arm I (Rifaximin, Pertuzumab-based Chemotherapy)Number of Patient With a Reduction of Mean Number of Stools7 Participants
Arm II (Pertuzumab-based Chemotherapy)Number of Patient With a Reduction of Mean Number of Stools0 Participants
Other Pre-specified

Changes in the Fecal Microbiome, Hydrogen Breath Test, and Permeability Test - Pertuzumab

Descriptive statistics (mean, sd, median, iqr) and longitudinal plots (raw value, change, change in percentage) will be used to summarize the baseline levels of hydrogen/methane peak by hydrogen breath test, diversity of gut microbiome (number of species) and specific species by fecal microbiome, and levels of urine mannitol and lactulose by permeability test before and after pertuzumab-based chemotherapy.

Time frame: Baseline up to 3 years

Other Pre-specified

Changes in the Fecal Microbiome, Hydrogen Breath Test, and Permeability Test - Rifaximin

Descriptive statistics (mean, standard deviation \[sd\], median, interquartile range \[iqr\]) and longitudinal plots (raw value, change, change in percentage) will be used to summarize the baseline levels of hydrogen/methane peak by hydrogen breath test , diversity of gut microbiome(number of species) and specific species by fecal microbiome, and levels of urine mannitol and lactulose by permeability test before and after rifaximin.

Time frame: Baseline up to 3 years

Other Pre-specified

Difference in the Fecal Microbiome, Hydrogen Breath Test, and Permeability Test

Descriptive statistics (mean, sd, median, iqr) and longitudinal plots (raw value, change, change in percentage) will be used to the fecal microbiome, hydrogen breath test, and permeability test among patients with or without PIGT. The study is not powered to detect any differences between the two arms; the main purpose is to quantify and evaluate differences descriptively between patients who develop and do not develop PIGT (between arm 1 and arm 2) to inform subsequent research.

Time frame: Up to 3 years

Source: ClinicalTrials.gov · Data processed: Feb 9, 2026