Clinical trial NCT06916689: Efficacy And Tolerability Of Asymmetric Split Regimen For Bowel Preparation
Official title: Efficacy And Tolerability Of The Asymmetric Split Regimen With A Very Low Volume Bowel Preparation: Split-The-Split Study
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Colon Preparation
Polyps Colorectal
Keywords: Asymmetric split regimen
Bowel preparation
Colon cleansing
Very low volume preparation
1L PEG + ascorbate
Lead sponsor: ASST Rhodense
Sponsor class: OTHER
First posted: 2025-04-08
Enrollment: 236
Sex: ALL
Minimum age (years): 50
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: DIAGNOSTIC

Brief summary: The investigators aimed to compare the efficacy for bowel cleansing of a split-dose regimen with a low morning dose of PEG solution (Asymmetric; 25% of the dose is given on the day of the procedure and 75% of the dose is given on the day before) with the standard split-dose regimen in patients undergoing screening and surveillance colonoscopy using a very low volume bowel preparation (1L PEG+Ascorbate). Consecutive outpatients undergoing screening and surveillance colonoscopy were enrolled in a randomized, single-blind, non-inferiority clinical trial. Patients were randomly assigned to: group A, asymmetric split dose regimen (0,75 L of PEG + ASC the day before and 0,25 L 2:30 hours before colonoscopy); group B, symmetric split dose regimen (0,5 L of PEG + ASC the day before and 0,5 L 3 hours before colonoscopy). Primary endpoint was the proportion of adequate bowel cleansing. Moreover, all patients filled in a validated, nurse-administered questionnaire assessing compliance, tolerability and safety of bowel preparation.

Detailed description: Prospective observational, single-blind study conducted in two endoscopy centers belonging to the same Local Health Authority. The two bowel preparation regimens under study (symmetric split and asymmetric split) will be compared in a population of patients undergoing screening for colorectal cancer.

Patient enrollment, product prescription, and the subsequent pre-endoscopic evaluation of safety, tolerability, acceptability, and compliance will be carried out by an assistant who will not be blinded to the type of preparation used.

Endoscopic evaluation, however, will be performed by an experienced endoscopist who will be blinded to the type of bowel preparation administered to the patient.

The bowel preparation product used consists of a very low-volume solution of Macrogol (3350) + Ascorbic Acid (1 liter) (PLENVU®, Norgine).

Bowel cleanliness level assessed using the Boston Bowel Preparation Scale adn overall tolerability of bowel preparation are primary outcomes.

Patient compliance and safety; the number of detected lesions, the percentage of complete colonoscopies, the duration of the colonoscopy, the degree of discomfort/pain perceived by the patient during the examination, and procedure-related complications are secondary outcomes.

Patients will be assigned to the two treatment groups according to a computer-generated sequence.

Data will be expressed as mean and standard deviation for quantitative variables and as frequencies for qualitative variables. The comparison between the two groups will be performed using the t-test for quantitative variables and the chi-square (χ²) test for qualitative variables.

Eligibility criteria: Inclusion Criteria:

* All patients scheduled as outpatient for screening or surveillance colonoscopy

Exclusion Criteria:

* Inpatients
* refusal of split dose regimen for bowel preparation
* previous history of colorectal resection
* severe cardiac disease
* advanced (stage IV and V) chronic kidney disease
* pregnancy; ileus
* suspected bowel obstruction or toxic megacolon
* known inflammatory bowel disease
* known or suspected allergy to PEG.

Primary outcomes:
measure: Quality of bowel prepreparation
timeFrame: 2 days
Secondary outcomes:
measure: Adenoma detection rate
timeFrame: 2 days
measure: Rate of the occurrence of adverse events
timeFrame: 2 days
measure: Compliance
timeFrame: 2 days
measure: Tolerability of the preparation, as reported by the patient on a Validated Questionnaire
timeFrame: 2 days
Other outcomes:
Locations:
city: Garbagnate Milanese
country: Italy
facility: ASST Rhodense
state: Lombardia
Study officials:
affiliation: ASST Rhodense
name: Gianpiero Manes
role: PRINCIPAL_INVESTIGATOR
References: