2.2. Study Design and Participant Selection
ICH
This study was conducted between 30 October 2019 and 6 January 2020 in Guelph, ON, Canada, and recruited participants from the general population in Guelph and the surrounding area. On-site monitoring was conducted according to the Clinical Monitoring Plan. The data management and statistical analyses for this study were conducted according to Standard Operating Procedures based on the International Council for Harmonization (ICH; The study protocol and related documents were approved by Canadian Shield Ethics Review Board (REB Tracking Number: 19-10-001; Burlington, ON, Canada) on 29 October 2019. A sample size calculation determined that a minimum total sample of The investigator or investigator’s representative explained the nature of the study to the participant or the participant’s legally authorized representative and answered all questions regarding the study. Participants were informed that their participation was voluntary and that any study report or publication of the study results would not disclose the participant’s identity without specific consent. Participants wishing to participate in the study, or their legally authorized representative, were required to sign a statement of informed consent that met the requirements of local regulations, ICH guidelines, and the research ethics board. The authorized person obtaining the informed consent also signed the informed consent form (ICF). A copy of the ICF was provided to the participant or the participant’s legally authorized representative. Written informed consent was obtained prior to any study-related procedures.Participants enrolled in this study were healthy adults between 18–69 years of age with a body mass index (BMI) of 18.0 to 34.9 kg/mThis was a randomized, double-blind, placebo-controlled three-arm parallel-group study (CONSORT Diagram; Participants collected a fecal sample within 72 h prior to the Day 0 visit and transferred it to the clinic site within 24 h of collection. Stool samples for microbiome analysis were collected using the OMNIgene-Gut kits as per the manufacturer’s instructions. During the baseline visit (Day 0), the participants were randomized to receive one of three study interventions as indicated by the randomization scheme: High dose (7 g resistant potato starch (RPS)), low dose (3.5 g RPS combined with 3.5 g digestible corn starch), or placebo (7 g digestible corn starch). The randomization scheme was generated by Nutrasource Pharmaceutical and Nutraceutical Services using SAS 9.4 PROC PLAN with Seed Number: 1887363180. Seventy-five participants were randomized into 25 blocks, with each block containing 3 participants. The first dose of study intervention was demonstrated by study staff and administered by mixing the product in approximately 125 mL of cool or room temperature water and having the participant drink it immediately before the investigational product settled. Participants were instructed to consume the investigational product in the morning. Bowel habit/daily diaries, stool collection supplies, and a 31-day supply of the study intervention were provided to the study participants during the baseline visit.At Visit 3 (Week 1), previous bowel habit diaries, unused study interventions, and empty product packaging were collected, and compliance was calculated. New bowel habit diaries and stool collection supplies were provided to the participants. At Visit 4 (Week 4, the final study visit), previous bowel habit diaries, unused study products, and empty packaging were collected, and compliance was calculated. Participants collected fecal samples within 72 h prior to Visit 3 (Week 1) and Visit 4 (Week 4) and transferred them to the clinic site within 24 h of each collection.Participants returned all sachets, including any open or unopened sachets, during both the 3rd and 4th visits. Compliance was calculated based on the amount of study product consumed compared to the total amount of study product expected to have been consumed for the given duration. Compliance for this study was considered acceptable if participants consumed an average of ≥80% of the study product for the given duration. Safety profiles were based on the safety analysis set (SAF; 