NCT04791644: Microbiote

Faecal Microbiota Characterization in Lynch Syndrome (LS) Patients With or Without Colorectal Neoplasia

Status unknown Last updated 18 May 2021

What this trial tests

trial in Lynch Syndrome in 285 participants. Status unknown.

Timeline

20 April 2021

Primary endpoint
30 December 2024

30 December 2024

Quick facts

Lead sponsor	Assistance Publique - Hôpitaux de Paris
Status	Status unknown
Study type	OBSERVATIONAL
Enrollment	285
Start date	20 April 2021
Primary completion	30 December 2024
Estimated completion	30 December 2024
Sites	1 location across France

Conditions studied

• Lynch Syndrome — all drugs for Lynch Syndrome →

Sponsor

Assistance Publique - Hôpitaux de Paris — full company profile →

Who can join

Adults 18 to 75, any sex, with Lynch Syndrome. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

Colorectal cancer (CRC) is the second cause of cancer-related death in western countries. CRC prevention and screening are major public health issues. Better knowledge of colorectal carcinogenesis could lead to better prevention. Gut microbiota (GM) is a complex community of bacteria, fungi, protozoa, viruses and bacteriophages which live in a symbiotic and epigenetic relationship with the host. GM can promote either digestive health or CRC through inflammatory and proliferative effects.

Lynch syndrome (LS) is the most common familial CRC syndrome with a lifetime CRC risk of 52% in women and 69% in men. The risk of CRC depends upon type of altered mismatch-repair gene and environmental factors (diet, exercise, obesity, tobacco and alcohol intake, etc.). Regular surveillance including annual or biannual colonoscopy is recommended in LS patients.

Chemoprevention has the potential to represent a cost-effective intervention in these high-risk patients and could allow a delay in colonoscopy surveillance. Regular low dose aspirin use is associated with a 20 to 30% reduction in the risk of sporadic colonic adenomas and CRC. The real benefit of aspirin is still to be consolidated. AAS-Lynch trial is an ongoing prospective multicenter (n=37), double-blind, placebo-controlled, randomized clinical trial, designed to investigate whether daily aspirin, at a dose of 100 or 300 mg compared with placebo, would decrease the occurrence or recurrence of colorectal adenomas in LS patients. The primary endpoint is the number of patients with at least one adenoma detected by chromo-endoscopy 48 months after initial colon clearance. At randomization and at the end of study, stool collection, blood collection, quality of life questionnaire, validated food frequency questionnaire (SU-VI-MAX2) and physical activity questionnaire are performed.

The ongoing AAS-Lynch study allow accessing to a unique fecal collection in very well characterized LS patients including a comprehensive dietary evaluation at high risk for colorectal neoplasia and planned colonoscopy surveillance during a 48 months follow-up, exposed or not exposed to chronic low dose aspirin. The expertise of the scientific consortium with state of the art microbiota analysis, the comprehensive collection of data and the prospective design of the study will allow the evaluation of the true role of gut microbiota in CRC carcinogenesis.

Publications & conference data

2 peer-reviewed publications reference this trial (live from Europe PMC):

1. Loss of symbiotic and increase of virulent bacteria through microbial networks in Lynch syndrome colon carcinogenesis.
   Sadeghi M, Mestivier D, Carbonnelle E, Benamouzig R, et al · · 2023 · cited 2× · PMID 38375206 · DOI 10.3389/fonc.2023.1313735
2. A Century of Bacteriophages: Insights, Applications, and Current Utilization.
   Dkhili S, Ribeiro M, Slama KB. · · 2025 · PMID 41301576 · DOI 10.3390/antibiotics14111080