Emergence of Bacterial Resistance to Antibiotics in the Digestive Microbiota of Patients Treated With Anticancer Drugs

Launched by CENTRE GEORGES FRANCOIS LECLERC · Jul 22, 2025

Keywords

ClinConnect Summary

This clinical trial is studying how certain cancer treatments might cause changes in the bacteria living in the gut, specifically looking at whether these treatments lead to the development of antibiotic-resistant bacteria. Some chemotherapy drugs not only attack cancer cells but may also affect gut bacteria in a way that could make them resistant to antibiotics. The study aims to understand how these changes might impact the immune system, the health of the gut lining, and the overall effectiveness of cancer treatments.

Adults over 18 who have not yet started chemotherapy and who are about to receive treatment for specific cancers—such as cervical, endometrial, gynecological, pancreatic, or certain types of head, bladder, or breast cancers—may be eligible. Participants will be divided into two groups based on the type of chemotherapy they receive: one group getting treatments that affect gut bacteria in this way, and another group getting treatments that do not. If you join the study, you’ll provide stool and blood samples twice—once shortly after starting chemotherapy and again after the third treatment cycle. These samples will help researchers learn more about how the treatments affect gut bacteria and overall health. The study is not yet recruiting but hopes to improve understanding of how cancer therapies interact with the body’s bacteria, which could lead to better care in the future.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • Men and women over 18
• • Chemotherapy-naive patients.
• * Patients due to start chemotherapy/radio chemotherapy who meet the criteria of the cohorts listed below :
• • 1. Squamous cell carcinoma of the upper aerodigestive tract (Non-metastatic, locally advanced, operable or not; Patients receiving concomitant radiochemotherapy using a platinum salt (cisplatin, carboplatin))
• • 2. Cervical and endometrial cancer (ocally advanced, Non-metastatic; Patients receiving concomitant radiochemotherapy using a platinum salt (cisplatin, carboplatin))
• • 3. Gynecological cancer (advanced stage ; Patient to receive platinum salt + paclitaxel chemotherapy)
• • 4. Mammary carcinoma (localised; Patient to receive adjuvant or neoadjuvant chemotherapy with epirubicin and cyclophosphamide without other associated treatment (targeted therapy / immunotherapy))
• • 5. Urothelial carcinoma (all stage ; Patient to receive neoadjuvant or adjuvant chemotherapy with platinum salt and gemcitabine)
• • 6. Pancreatic adenocarcinoma (localised or metastatic ; Patients to be treated with gemcitamine alone or in combination with nab-paclitaxel)
• • OMS ≤ 2
• • Affiliation with a French social security scheme or beneficiary of such a scheme.
• • Signed informed consent indicating that the patient has understood the purpose and procedures of the study and agrees to participate in the study and to abide by the study requirements and restrictions
• Exclusion Criteria:
• • Patients unable to collect / send stools for medical, geographical, social or psychological reasons.
• • Patients who have already received chemotherapy/radiochemotherapy.
• • Use of anti-infectives for systemic use within 6 months prior to the first sampling, or any other concomitant disease/condition that may influence stool analysis.
• • Pregnant women and nursing mothers.
• • Persons deprived of their liberty by judicial or administrative decision; persons under compulsory psychiatric care; persons admitted to a health or social institution for purposes other than research.
• • Adults subject to a legal protection measure - safeguard of justice, guardianship or curatorship - or unable to express their consent.