Safety, Tolerability, and Biosignature of Humanized Prebiotics in Healthy Adults: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Safety, Tolerability, and Biosignature of Humanized Prebiotics in Healthy Adults (NCT06068894), a randomized na study. The primary outcome is Mean Composite PROMIS Maximum Scores.

2. Clinical Question

3. Trial Design

This was a randomized, parallel-group trial with quadruple masking, according to the registry. Its stated purpose was to evaluate the safety and tolerability of GOS and hGOS in healthy adults, and to examine biological measures associated with intestinal health. The registry identifies the study as completed. Its listed start date is 2024-06-13, and its primary completion date is 2025-03-26. The phase is recorded as NA.

The interventions were lactosamine-enriched humanized galacto-oligosaccharides (hGOS), GOS, and matching placebo. The study summary frames the dose as 15 g/day, while the individual arm descriptions give a range of 10-15 g/day for the supplements and placebo. Each arm description specifies an intervention period of 4 weeks. The powders could be added to a non-alcoholic beverage. More detail on dose selection, adherence, or how doses within the stated range were chosen is not reported in the registry record.

The primary measure was a composite PROMIS maximum gastrointestinal symptom score, assessed between week 0 and week 4. The stated secondary outcomes include mean percent change in relative abundance of beneficial bacteria and concentrations of interleukin-1α, interleukin-1ß, interleukin-6, interleukin-8, interleukin-12, interleukin-17, and interleukin-18. The registry lists 13 outcome measures overall.

The record reports enrollment of 60 but does not give the number assigned to each arm for the primary outcome analysis. It also does not report participant characteristics, allocation procedures beyond randomization, masking roles, adherence, or reasons for discontinuation. The sponsor is the University of North Carolina, Chapel Hill.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Before assignment: Sixty participants signed informed consent and enrolled in the study. Before the baseline visit (Week 0), 10 participants voluntarily withdrew consent, leaving 50 participants who completed the baseline assessment.

Overall Study

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Mean Composite PROMIS Maximum Scores, measured over Between week 0 (Baseline) and week 4.

The primary endpoint is titled Mean Composite PROMIS Maximum Scores. It measures gastrointestinal symptom severity using items from a GI questionnaire. The registry groups items into seven domains: abdominal pain, bloating, abdominal distension, flatulence, constipation, diarrhea, and nausea. Each item is scored from 0 to 4, with 0 described as never and 4 as always. For each domain at each visit, the domain score is the maximum item score. The composite PROMIS maximum is then described as the maximum severity score cumulatively across all seven domains at that visit, representing the participant's worst GI symptoms at that time.

The registry gives the composite score a range of 0-28 and says lower scores represent lowest GI symptoms. It specifies a mean and standard deviation as the summary statistics and identifies the timeframe as between week 0 (baseline) and week 4. Repeated symptom assessment can describe how reported symptoms vary over the intervention period. In general, a composite measure offers a way to represent multiple symptom domains together, while its maximum-based construction emphasizes the most severe recorded symptom information under the registry's scoring description.

The primary endpoint results, group summaries, and any estimated between-group effects are not reported in the registry record. The record also does not specify how the primary comparison was defined or how missing questionnaire items were handled.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes random allocation, quadruple masking, and a parallel model. Randomization is generally used to reduce systematic differences between intervention groups at assignment. Masking is generally intended to limit the influence of knowledge about assigned treatment on participant experience, care, measurement, or assessment. The record does not identify which people or roles were included in the quadruple masking, nor does it describe the allocation sequence or concealment procedures. The design labels alone do not establish how these procedures were implemented.

A parallel design means that the groups receive their assigned interventions during the same study period rather than crossing over between treatments. Here, the listed interventions are hGOS, GOS, and placebo, with an intervention period of 4 weeks. The registry describes the powder preparations and the beverage format. The summary states an aim to establish safety of a 15 g/day dose, whereas arm descriptions state 10-15 g/day. The record does not explain the difference between these dose descriptions or specify the dose received by each participant.

The primary outcome is a continuous score summarized as a mean with standard deviation. In general, a mean describes the average score and a standard deviation describes the spread of individual scores around that average. Those summaries can help readers understand both the typical score and how varied scores are, but they do not by themselves quantify a treatment contrast. For a group comparison, an effect estimate would ordinarily state the contrast being estimated and its uncertainty. No such primary-outcome estimate is reported in the registry record.

The endpoint description applies a maximum-based scoring approach within symptom domains and across the domains. Such a score can emphasize the worst recorded symptom rather than the typical level across all items. That feature can make the measure responsive to severe symptom reports, while also meaning that a change in the composite may reflect a change in the most severe domain rather than a broad change across every symptom. This is a general interpretation of maximum-based composite scores, not a reported finding from this trial.

In general, confidence intervals express uncertainty around an estimate and show which effect sizes are reasonably compatible with the data and analysis assumptions. A p-value, when reported, addresses how compatible the data are with a specified null hypothesis under a statistical model; it does not measure the size or clinical importance of an effect. Neither a primary estimate, confidence interval, nor p-value is reported in the registry record. The statistical model and any covariate adjustments are also not reported.

The registry's planning description says its sample-size illustrations use the observed effect, a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect, and distinguishes participant-per-arm planning for non-time-to-event outcomes from total-event planning for time-to-event outcomes. These are planning assumptions, not evidence about the trial's observed results or its actual design justification. The registry record does not report the numerical planning illustrations, the fraction values, a sample-size justification, or a calculation for the primary analysis. Such illustrations are not observed power and do not show that the trial had adequate precision.

Over-dispersion is a general issue for count outcomes: it occurs when variability exceeds what a simple count model assumes, and can make standard errors too small if not accommodated. The primary endpoint is described as a continuous symptom score, not a count outcome. The record does not identify a model for the secondary bacterial or biomarker outcomes, so it is not possible to say whether over-dispersion or other distributional features were considered.

For safety summaries, the registry reports counts of affected participants for serious events, other events, and deaths. In general, descriptive counts can identify what was recorded, but a comparative safety analysis also depends on clear event definitions, observation time, exposure, and a stated analytic approach. Those details and any inferential comparison are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists multiple outcome measures: the primary gastrointestinal symptom score and secondary measures involving beneficial bacteria and inflammatory biomarkers. Testing multiple outcomes or contrasts can increase the chance of finding at least one apparently unusual result by chance. In general, a multiplicity plan may identify which outcome is primary, define the family of comparisons, and specify whether or how statistical significance is adjusted. The registry record does not report a multiplicity strategy, a hierarchy among secondary outcomes, or adjusted statistical results. The primary outcome is identified by title, but its analysis is not posted.

The registry names 13 outcome measures overall and lists secondary measures that include mean percent change in relative abundance of beneficial bacteria and concentrations of several interleukins. It does not report estimates or tests for these outcomes. The record also does not report whether all registered outcomes were analyzed, whether outcomes were changed, or whether any analyses were exploratory. No statistical analyses are reported in the posted results.

Missing-data handling is not reported in the registry record. There is no information about missing questionnaires, incomplete follow-up, imputation, or sensitivity analyses. The number contributing data to the primary endpoint at week 0 and week 4 is not reported. Without this information, readers cannot assess whether the analysis included all randomized participants or only participants with available measurements.

The analysis populations are also not reported. The record does not state whether the primary analysis followed assignment regardless of adherence, included only participants who completed treatment, or used another population definition. These choices can affect the interpretation of a randomized comparison. The registry's completion status and enrollment figure do not resolve these analysis questions.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent non-serious adverse event terms

The registry reports no serious adverse events in the hGOS group, the GOS group, or the placebo group. It also reports zero deaths in each group. For other adverse events, it records 1 affected participant in the hGOS group, 0 in the GOS group, and 3 in the placebo group. The numbers at risk listed for these summaries are 17 for hGOS, 17 for GOS, and 16 for placebo.

These figures should be read as registry-reported counts, not as a formal comparison of safety. No statistical analysis, confidence interval, or test of group differences is reported. The record does not give descriptions of the other adverse events, their timing, severity, duration, or relationship to the interventions. It also does not explain whether participants could contribute more than one event to the summaries. The serious-event terms list is empty.

In general, a zero count means that no event of that specified category was recorded in the reported group; it does not establish that the underlying risk is zero. A numerical difference in observed counts alone does not establish a treatment-related difference, especially without event definitions, follow-up details, and an uncertainty estimate. The short intervention period of 4 weeks is the period described for treatment, but the record does not give further safety follow-up details.

12. What the Result Does, and Does Not, Mean

This registry record is useful for understanding the trial's design, intended outcomes, and the form of its safety reporting. It describes a randomized, quadruple-masked, parallel study in healthy adults comparing hGOS and GOS with placebo. The primary outcome was a composite gastrointestinal symptom score assessed from week 0 to week 4. The stated biological aims include examining beneficial gut bacteria and inflammatory biomarkers.

The record does not report the primary symptom-score results or results for the named secondary outcomes. It therefore cannot show whether scores changed, whether groups differed, or how precise any possible difference was. It also does not report a statistical model, group estimates, confidence intervals, or p-values for these outcomes. An endpoint's definition and a trial's completed status are not substitutes for the observed results.

The adverse-event summary records no serious adverse events and no deaths in any group, alongside the reported counts for other adverse events. These descriptive findings do not demonstrate that an intervention caused or prevented an event, and they do not establish comparative safety. Event details, attribution, and statistical uncertainty are not reported.

In general, a trial result is interpreted by considering the estimated effect, its uncertainty, the outcome definition, and the analysis population—not merely whether an outcome was planned or whether a trial was completed. For this record, the absence of posted estimates prevents that fuller assessment. The study's stated safety and biological questions remain distinct from conclusions that would require reported outcome data.

The registry record also does not establish that any measured biological change would correspond to a meaningful change in symptoms or health. The trial concerns healthy adults and the described intervention period is 4 weeks; its record does not report longer-term outcomes. These limitations define what can be inferred from the posted information, rather than making a claim about the interventions themselves.

13. Why This Trial Matters Statistically

This study raises a statistical question that is common in early clinical research: how to interpret a trial designed to examine both tolerability and several biological measures. Its randomized, quadruple-masked, parallel design identifies a comparative framework, while the primary endpoint combines information from multiple gastrointestinal symptom domains. The score's maximum-based construction is important because it emphasizes the most severe symptom information in the registry's scoring description.

Several dimensions of uncertainty would matter for interpretation: the size of any group contrast, variation in symptom scores, missing observations, and the number of participants contributing to the analysis. The registry does not report the primary results or these analysis details. As a result, the design can be described, but the precision of the primary estimate cannot be assessed from the posted results.

The study also names bacterial and inflammatory outcomes alongside its symptom endpoint. When research measures multiple outcomes, a clear plan for prioritizing and interpreting them is important. The registry record lists 13 outcome measures but does not report a multiplicity strategy or numerical secondary results. This makes it impossible to distinguish confirmatory findings from exploratory patterns on the basis of the posted information.

The safety counts offer a reminder that descriptive event totals and comparative evidence are different. Counts can show what was recorded in each group, but interpretation also depends on event definitions, follow-up, attribution, and uncertainty. These considerations are especially relevant when the record gives no inferential analysis.

The statistical value of the record is therefore mainly in its stated design and outcome definitions. It makes the intended comparison and measurement approach visible, while the absence of outcome estimates limits conclusions about the findings. This distinction helps readers separate a trial's research question from evidence that would answer it.

14. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The principal limitation for interpreting this trial record is that numerical results for the primary endpoint are not reported. There are no group means, standard deviations, between-group estimates, confidence intervals, or p-values for the composite PROMIS maximum score. Results for the listed secondary outcomes are also not reported. This prevents assessment of effect direction, magnitude, and precision.

The study summary describes a 15 g/day dose, while the arm descriptions state 10-15 g/day. The registry record does not explain this difference or specify participants' actual doses. The primary outcome is described as a mean score between week 0 and week 4, but the record does not state the exact comparison, model, or handling of repeated measurements.

Participant-level characteristics, arm-specific assignment counts for the primary outcome, adherence, discontinuations, and reasons for missing data are not reported in the registry record. Nor does it define analysis populations or describe imputation and sensitivity analyses. These omissions limit assessment of who contributed to the estimates and how missing observations could affect interpretation.

The record does not identify the roles covered by quadruple masking, detail the randomization process, or report a multiplicity plan. It lists adverse-event counts but not event descriptions, severity beyond the serious/other grouping, timing, attribution, or statistical comparisons. These limits do not imply that procedures or analyses were absent; they mean the relevant details are not reported in the registry record.

Finally, the intervention period is described as 4 weeks and the population as healthy adults. Longer-term outcomes and broader population characteristics are not reported, limiting conclusions about durability or applicability beyond the population and period described.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Safety, Tolerability, and Biosignature of Humanized Prebiotics in Healthy Adults — NCT06068894.
• Registry record last updated 2026-02-05; status last verified 2025-12.
• Results first posted 2026-02-05.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

18. Record Summary

The registry record describes NCT06068894, titled Safety, Tolerability, and Biosignature of Humanized Prebiotics in Healthy Adults. It lists the University of North Carolina, Chapel Hill as sponsor, enrollment of 60, randomized allocation, quadruple masking, a parallel model, and completed status. The phase is recorded as NA.

The study compared hGOS and GOS with matching placebo in healthy adults. The arm descriptions specify a 4-week intervention. The primary endpoint was mean composite PROMIS maximum gastrointestinal symptom scores between week 0 and week 4. Named secondary outcomes include beneficial bacteria and interleukin concentrations.

The registry reports no serious adverse events or deaths in any group, and gives counts for other adverse events. It does not report the primary outcome estimates, secondary outcome results, or statistical analyses. The record therefore describes the design and planned measures without providing enough outcome information to estimate the comparative effects.