A Phase 2 Randomized Trial of DCL-101, a Novel Pill-Based Colonoscopy Prep, vs 4L Polyethylene Glycol-Electrolyte Solution

Abstract

Introduction: DCL-101, a novel Pill Prep, is compositionally identical to standard 4L polyethylene glycol-electrolyte solution (PEG-ELS) and delivers the salt encapsulated, with PEG 3350 coadministered as a taste-free oral solution. The aim of this study was to compare the safety, taste, and tolerability of DCL-101 with 4L PEG-ELS in outpatients preparing for colonoscopy, with a secondary objective to assess efficacy.

Methods: This was a multicenter, randomized, investigator-blinded, phase 2 clinical trial of 45 adult patients undergoing outpatient colonoscopy. Patients were randomized 2:1 to either DCL-101 (3L in cohort 1; 4L in cohort 2) or 4L PEG-ELS, each administered with split dosing. Safety was assessed over 3 post-treatment clinic visits. Tolerability was measured using the Lawrance Bowel-Preparation Tolerability Questionnaire and the Mayo Clinic Bowel Prep Tolerability Questionnaire. Efficacy was determined by expert central readers, blinded to treatment, using the Ottawa Bowel Preparation Quality Scale, Boston Bowel Preparation Scale, and Aronchick scale.

Results: Both DCL-101 doses had superior taste and tolerability relative to 4L PEG-ELS. All adverse events were grade 1 with no significant differences in adverse events among the 3 regimens. There were no significant differences in efficacy among the 3 treatments as defined by the centrally read Ottawa Bowel Preparation Quality Scale, Boston Bowel Preparation Scale, or Aronchick scores. There were no inadequate preps as judged by the site endoscopist.

Discussion: DCL-101 Pill Prep is a novel strategy that vastly improves the taste and tolerability of PEG-ELS solutions with safety and efficacy comparable with split-dose 4L PEG-ELS solutions.

Trial registration: ClinicalTrials.gov NCT02910440.

Conflict of interest statement

Guarantor of article: Dale R. Bachwich, MD.

Specific author contributions: Dale R. Bachwich, MD, and James D. Lewis, MD, MSCE, contributed equally to this article and are cofirst authors. D.R.B., J.D.L., and V.O.K.: conception and design; analysis and interpretation of the data; drafting of the article; critical revision of the article for important intellectual content; and final approval of the article. B.C.J.: conception and design; analysis and interpretation of the data; critical revision of the article for important intellectual content; and final approval of the article. A.H.C.: analysis and interpretation of the data; critical revision of the article for important intellectual content; and final approval of the article. M.L.K.: conception and design; analysis and interpretation of the data; critical revision of the article for important intellectual content; and final approval of the article. All the authors had full access to the data during the creation of this manuscript, and all authors approved the final version of this article, including the authorship list.

Financial support: This study was funded in full by Dark Canyon Laboratories, LLC, Rapid City, South Dakota (darkcanyonlabs.com). No governmental or nonprofit grants were used to support this work. Study sponsors were involved in study design, interpretation of the data, and writing of the report. Data collection and initial analysis was performed by Robarts Clinical Trials, and additional statistical analysis was performed by Theresa P. Stern, PhD.

Potential competing interests: D. R. Bachwich: Shareholder, Board Member, and Executive of Dark Canyon Laboratories, LLC. J. D. Lewis: Shareholder and Advisory Board Member of Dark Canyon Laboratories, LLC. V. O. Kowal: Shareholder, Board Member, and Executive of Dark Canyon Laboratories, LLC. B. C. Jacobson: Consultant to Dark Canyon Laboratories, LLC, and Motus GI Holdings. A. H. Calderwood: Consultant to Dark Canyon Laboratories, LLC. M. L. Kochman: Shareholder and Advisory Board Member of Dark Canyon Laboratories, LLC; Consultant to Olympus, Boston Scientific, and Pentax; Shareholder and Consultant to Virgo Surgical Video Solutions.

ClinicalTrials.gov identifier: NCT02910440.

Figures

Figure 1.

CONSORT diagram for (a) cohort 1 and (b) cohort 2. ECG, electrocardiogram; GI, gastrointestinal; PEG-ELS, polyethylene glycol-electrolyte solution.

Figure 2.

Mayo Questionnaire Tolerability Scores for (a) cohort 1 and (b) cohort 2. DCL-101 at both doses has superior tolerability than PEG-ELS 4L. PEG-ELS, polyethylene glycol-electrolyte solution.

Figure 3.

Mayo Questionnaire Tolerability Scores. More patients were mostly willing to use DCL-101 4L again compared with PEG-ELS 4L. PEG-ELS, polyethylene glycol-electrolyte solution.

Figure 4.

Exploratory question regarding dread once prep was one-half completed for (a) cohort 1 and (b) cohort 2. Patients taking DCL-101 reported less dread than those taking PEG-ELS. PEG-ELS, polyethylene glycol-electrolyte solution.