Bowel-cleansing efficacy of the 1L polyethylene glycol-based bowel preparation NER1006 (PLENVU) in patient subgroups in two phase III trials

Factors affecting the quality of bowel preparation for colonoscopy in hard-to-prepare patients: Evidence from the literature

Adequate bowel cleansing is critical for a high-quality colonoscopy because it affects diagnostic accuracy and adenoma detection. Nevertheless, almost a quarter of procedures are still carried out with suboptimal preparation, resulting in longer procedure times, higher risk of complications, and higher likelihood of missing lesions. Current guidelines recommend high-volume or low-volume polyethylene glycol (PEG)/non-PEG-based split-dose regimens. In patients who have had insufficient bowel cleansing, the colonoscopy should be repeated the same day or the next day with additional bowel cleansing as a salvage option. A strategy that includes a prolonged low-fiber diet, a split preparation regimen, and a colonoscopy within 5 h of the end of preparation may increase cleansing success rates in the elderly. Furthermore, even though no specific product is specifically recommended in the other cases for difficult-to-prepare patients, clinical evidence suggests that 1-L PEG plus ascorbic acid preparation are associated with higher cleansing success in hospitalized and inflammatory bowel disease patients. Patients with severe renal insufficiency (creatinine clearance < 30 mL/min) should be prepared with isotonic high volume PEG solutions. Few data on cirrhotic patients are currently available, and no trials have been conducted in this population. An accurate characterization of procedural and patient variables may lead to a more personalized approach to bowel preparation, especially in patients undergoing resection of left colon lesions, where intestinal preparation has a poor outcome. The purpose of this review was to summarize the evidence on the risk factors influencing the quality of bowel cleansing in difficult-to-prepare patients, as well as strategies to improve colonoscopy preparation in these patients.

Effects on BBPS score with bowel preparation time and dosage

BACKGROUND

To evaluate the effects on the Boston Bowel Preparation Scale (BBPS) score with different bowel preparation times and dosages.

METHODS

Six hundred patients who underwent colonoscopy in the Endoscopy Center of Ningbo No.9 Hospital in 2021 were recruited and randomly assigned to 3 groups: Group A: "4-hour 1 + 2L" bowel preparation regimen; Group B: "6-hour 1 + 2L" bowel preparation regimen; and Group C: "4-hour 0 + 2L" bowel preparation regimen. BBPS score among these groups is compared and analyzed in the Statistical Product and Service Solutions software.

RESULTS

There was no difference in baseline characteristics among the three groups of patients (P > .05). There was no significant difference in the BBPS score between Group B and Group C, whereas the BBPS score in Group A was significantly higher than that in Groups B and C (P < .05).

CONCLUSION

The "4-hour 1 + 2L" bowel preparation regimen can obtain higher BBPS score for colonoscopy, which is suggested to be the optimal plan for colonoscopy patients of the time and dosage. Definitely, higher BBPS score can improve the quality of colonoscopy diagnosis and treatment consequence.

The Effectiveness and Tolerability of a Very Low-Volume Bowel Preparation for Colonoscopy Compared to Low and High-Volume Polyethylene Glycol-Solutions in the Real-Life Setting

Adequate bowel cleansing is essential for high-quality colonoscopy. Recently, a new very low-volume 1 litre (1L) polyethylene glycol (PEG) plus ascorbate solution (ASC) has been introduced. Our aims were to assess the effectiveness and tolerability of this product compared to low-volume 2L PEG-ASC and high-volume 4L PEG solutions, in a real-life setting. In six endoscopy units in Sweden, outpatients undergoing colonoscopy were either prescribed solutions according to local routines, or the very low-volume solution in split dose regimen. Bowel cleansing effectiveness and patient experience was assessed using the Boston Bowel preparation scale (BBPS) and a patient questionnaire. A total of 1098 patients (mean age 58 years, 52% women) were included. All subsegment and the total BBPS scores were significantly greater for 1L PEG-ASC in comparison to other solutions (p < 0.05 for 1L PEG-ASC and 4L PEG for transverse and left colon, otherwise p < 0.001). Nausea was more frequent with 1L PEG-ASC compared to 2L PEG-ASC (p < 0.001) and vomiting were more often reported compared to both other solutions (p < 0.01 and p < 0.05 for 2L PEG-ASC and 4L PEG, respectively). Smell, taste, and total experience was better for 1L PEG-ASC compared to 4L PEG (p < 0.001), and similar compared to the 2L PEG-ASC. In conclusion, 1L PEG-ASC leads to better bowel cleansing compared to 2L PEG-ASC or 4L PEG products, with similar or greater patient satisfaction.

1L NER1006 can improve rates of adequate and high-quality bowel cleansing in the right colon: a post hoc analysis of two randomised clinical trials

BACKGROUND

The right colon is difficult to cleanse compared with other colon segments. This post hoc analysis of two randomised clinical trials (MORA and NOCT) examined whether 1L polyethylene glycol (PEG) NER1006 and two mid-volume alternatives could improve adequate and high-quality cleansing in the right colon among patients with complete cleansing assessments.

METHODS

Patients received NER1006 (N2D), 2L PEG plus ascorbate (2LPEG) or oral sulphate solution (OSS) as a 2-day evening/morning split-dosing regimen or NER1006 as a same-day morning-only dosing regimen (N1D). Patients had full segmental scoring assigned by treatment-blinded central readers using the Harefield Cleansing Scale. The right colon adequate (score ≥ 2) and high-quality (score ≥ 3) cleansing success of NER1006 (N2D and N1D) versus 2LPEG and OSS was analysed individually and as pooled groups (N2D vs. 2LPEG/OSS). We assessed the comparative right colon cleansing rates of the N2D versus 2LPEG/OSS in overweight males. We also performed a multivariable regression analysis to examine factors affecting cleansing in the right colon.

RESULTS

A total of 1307 patients were included. Pooled N2D showed significantly improved rates of adequate-level cleansing in the right colon compared with 2LPEG (97.5% [504/517] vs. 94.6% [246/260]; p = 0.020) and OSS (97.5% [504/517] vs. 93.8% [244/260]; p = 0.006). In MORA, the rate of adequate right colon cleansing did not significantly differ between N1D and 2LPEG (95.2% [257/270] vs. 94.6% [246/260]; p = 0.383). The rate of right colon high-quality cleansing was significantly improved with N2D or N1D vs. 2LPEG (p < 0.001 for both), and was numerically higher with N2D versus OSS (p = 0.11). In overweight males, NER1006 delivered numerically higher adequate (p = 0.398) and superior high-quality (p = 0.024) cleansing rates versus 2LPEG/OSS. Multivariable regression analysis showed NER1006 was associated with adequate and high-quality cleansing (p = 0.031 and p < 0.001), while time between preparation and colonoscopy was negatively associated (p = 0.034 and p = 0.006).

CONCLUSIONS

NER1006 delivered improved rates of adequate and high-quality right colon cleansing compared with 2LPEG and OSS. The increased rate of high-quality cleansing with NER1006 versus its comparators was also seen in overweight males.