Study of the MUC1 Peptide-Poly-ICLC Adjuvant Vaccine in Individuals With Advanced Colorectal Adenoma: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Study of the MUC1 Peptide-Poly-ICLC Adjuvant Vaccine in Individuals With Advanced Colorectal Adenoma (NCT00773097), a na phase 2 study. The primary outcome is Number of Participants With Anti Muc-1 Antibody.

2. Clinical Question

The clinical motivation described in the registry is that MUC1 is normally present in the colon lining and is expressed in a larger amount and modified form on adenomatous polyps and colorectal cancer. The proposed vaccine was intended to prompt recognition of these changes. That rationale explains why an immune response was measured; it does not establish that the vaccine prevented polyps from recurring or advancing.

The primary question is therefore about an immune-response measure in a selected population, not a direct comparison of cancer outcomes between vaccine and control groups. The registry also names autoimmune response and adverse events associated with the study agent as secondary outcomes. Their results are not reported in the registry record.

3. Trial Design

This completed Phase 2 study is registered as a single-group trial of MUC1 peptide vaccine with Poly-ICLC in people with a history of advanced colorectal adenoma. The registry lists enrollment of 46, allocation as not applicable, and masking as none. It lists the study start as 2008-10 and primary completion as 2011-10. The sponsor is Robert Schoen.

The study has no listed control arm. Consequently, its design does not provide a like-for-like comparison between participants receiving the vaccine and participants assigned to another treatment or to no treatment. The registry identifies the intervention as a biological agent and describes the goal as evaluating immune response. Its primary outcome is the number of participants with anti-MUC1 antibody at 52 weeks.

Six of the 46 people who consented did not receive vaccine. The registry gives the reasons: 4 had abnormal screening laboratory tests, 1 did not meet criteria for an advanced adenoma, and 1 declined to participate. These details matter when interpreting who entered the treated group and any outcome analysis. The number of participants included in the primary-outcome analysis is not reported in the registry record.

The registry lists three outcome measures, including the primary antibody outcome and secondary outcomes for autoimmune response and adverse events associated with the study agent. It has no analysis records. That does not establish what analyses investigators may have performed outside the registry; statistical methods and outcome results are not reported in the registry record. The record does not describe a randomized comparison, and no control-group estimate can be interpreted from this study.

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: The subjects were excluded if they had a history of a heritable cancer syndrome, autoimmune disease, or a malignancy within 5 years before the enrollment, excluding nonmelanoma skins cancer.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Of the 46 subjects who consented to participate, 6 did not receive vaccine: 4 had abnormal screening laboratory test, 1 did not meet criteria for an advanced adenoma, and 1 declined to participate

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.

Population: A total of 39 subjects completed the 52 weeks of the study.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With Anti Muc-1 Antibody, measured over 52 weeks.

The primary endpoint is the number of participants with anti-MUC1 antibody, assessed at 52 weeks. It is intended to capture an immune response to the MUC1 peptide vaccine administered with Poly-ICLC in people with a history of advanced colorectal adenoma. The registry describes the outcome as a participant count rather than a continuous antibody concentration.

As a general statistical point, a count endpoint can describe how many people satisfy a defined outcome, but its interpretation depends on the criteria used to classify participants as having that outcome. The threshold or assay rule used to define an anti-MUC1 antibody response is not reported in the registry record. The antibody result itself, including the number meeting the endpoint, is also not reported in the registry record.

An immune-response endpoint is relevant to the study’s stated purpose of evaluating whether the vaccine prompts a response to MUC1. It is not a direct measure of whether advanced adenomas recur, progress, or lead to colorectal cancer. The registry describes prevention of polyp recurrence or progression as the broader development goal, but those are not the listed primary endpoint. The reported endpoint description alone cannot establish a clinical prevention effect.

The named assessment time is 52 weeks. The registry does not report how many participants completed that assessment, how missing antibody measurements were handled, or whether any additional time points informed the primary analysis.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry classifies the primary outcome as a number of participants with an event. In this study, the event is having anti-MUC1 antibody at the 52-week assessment. This is a binary classification at the participant level: each participant is counted as meeting or not meeting the endpoint, according to criteria that are not reported in the registry record. The observed count and analysis denominator are also not reported in the registry record.

As a general statistical explanation, a binary outcome can be presented as a count, a proportion, or a comparison of proportions. A count without its denominator does not convey how common the outcome was among those assessed. A proportion still needs a clearly defined analysis population and a clear rule for handling participants whose outcome is unavailable. Those details are not reported in the registry record for the primary outcome.

A confidence interval is a range expressing uncertainty around an estimate under a specified statistical method. In general, its width depends on the amount of information and the variability in the data, as well as the method used. No confidence interval or other measure of precision for the primary antibody outcome is reported in the registry record. The outcome count and denominator needed to understand a direct estimate are not reported either.

A p-value is a measure calculated under a statistical model and a specified null hypothesis; it is not a measure of the size or importance of an effect. The registry record contains no analysis records, and no primary-outcome p-value or hypothesis-testing method is reported in the registry record. The null hypothesis, if any, is not reported in the registry record. In a single-group study, a statistical test would need a defined reference value or other comparison to answer a particular question. Such a reference is not reported in the registry record.

The trial is recorded as single-group, with allocation not applicable and masking none. General methods for randomized comparisons of treatment groups therefore should not be read as if they describe this trial. No randomized treatment contrast is available. Even if an immune response were reported, a single-group result would describe the participants observed under this study’s conditions; by itself it would not estimate a vaccine-versus-control difference.

The study’s sample-size illustrations use a hypothetical two-arm planning framework: two-sided significance level 0.05, equal allocation between two arms, and a normal approximation, with effects described as fractions of an observed effect. These are planning illustrations, not the design of the single-group trial and not observed power. The registry does not report the trial’s own sample-size justification. The primary outcome result is absent, so the effect used for those illustrations cannot be independently interpreted from the registry record. No numerical planning values are stated in this explanation.

As a general concept, power is a design property calculated under assumptions about an effect, variability, sample size, and analysis. A retrospective calculation based on an observed effect does not show the probability that the study’s hypothesis was true, nor does it repair a missing outcome result. Sample-size illustrations should therefore be read as conditional planning exercises rather than evidence about the certainty of the trial findings.

Over-dispersion is a general issue that arises when observed variation in count data exceeds what a chosen model assumes. It can make standard errors too small if the model does not accommodate the extra variability. The registry identifies the primary outcome as a count of participants with an event, but does not report a count model, a dispersion estimate, or an over-dispersion assessment. Because the outcome is described as a participant count for a binary response, the applicability of count-model methods would depend on the actual analysis and data structure; those are not reported in the registry record.

The record lists 3 outcome measures and 0 analysis records. This indicates that outcome descriptions are present without corresponding analysis records in the registry. It does not establish that investigators conducted no analyses; any analyses not represented in the registry are not reported in the registry record. The statistical analysis plan, any adjustment strategy, and the methods used to calculate uncertainty are not reported in the registry record.

For safety outcomes, the registry provides participants at risk and participants affected for the listed group. As a general principle, safety counts are most interpretable when their event definitions, observation periods, ascertainment procedures, and participant denominators are clear. The serious adverse event figures give a denominator of 39 and a count of 0, while the event terms and details are not reported in the serious-event listing. The registry does not report additional methods that would permit a more detailed safety analysis.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("MUC1 Poly-ICLC")
n      <- c(39)
events <- c(39)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  MUC1 Poly-ICLC  39  39  100.0  91.0  100.0  91.0  100.0  91.2  99.9

11. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary antibody outcome and two secondary outcomes: autoimmune response to the MUC1 vaccine and adverse events associated with the study agent. It does not report a multiplicity plan. It is therefore not reported in the registry record whether investigators prespecified a hierarchy, adjusted for multiple comparisons, or treated secondary analyses as descriptive. Without the results and analysis plan, the impact of multiple outcome testing cannot be assessed.

The record contains no analysis records. The number of participants with a 52-week antibody result, the amount of missing primary-outcome data, and the method used to handle missing data are not reported in the registry record. The registry also does not state whether the primary analysis included all consented participants, only participants who received vaccine, or another defined analysis population.

The registry does report that 6 of the 46 people who consented did not receive vaccine, with reasons given for those exclusions. This is useful for understanding participation before vaccination, but it does not describe later follow-up or outcome availability. The record does not report whether those participants were included in any outcome analysis or whether other participants lacked measurements.

As a general statistical point, missing outcomes can affect interpretation if availability is related to participants’ response or other characteristics. The extent and handling of missingness should be described before a result is interpreted. Since the outcome result, denominator, analysis population, and missing-data approach are not reported in the registry record, the direction or size of any missing-data effect cannot be evaluated.

12. Safety Results

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

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 0 participants with serious adverse events among 39 at risk in the MUC1 Poly-ICLC group. It also reports 39 participants with other adverse events among 39 at risk. These are participant counts, not event rates calculated for a different observation period. The registry does not provide serious adverse event terms in its listing, and details such as event type, timing, severity, and duration are not reported in the registry record.

As a general distinction, seriousness is a regulatory classification and is not interchangeable with the intensity of a symptom. A count of serious adverse events therefore does not describe every aspect of tolerability. The other-adverse-event count indicates that participants were recorded in that category, but the registry record does not report the specific events or enough detail to characterize them.

The deaths field is not populated with a count; deaths are not reported in the registry record. That should not be read as a confirmed count of zero. The registry also does not report enough information to determine whether an event was caused by the study agent. The figures are descriptive safety entries and do not establish causation.

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

The registry establishes that a completed Phase 2, single-group study evaluated MUC1 peptide vaccine with Poly-ICLC in people with a history of advanced colorectal adenoma. Its primary outcome was the number of participants with anti-MUC1 antibody at 52 weeks. The registry does not report the primary outcome result, so the observed immune response and its precision cannot be described from this record.

The absence of a control group limits what a single-group result could establish even if the immune-response count were available. Without a comparator, the study cannot provide a direct estimate of how outcomes differed between vaccinated and unvaccinated participants. The registry does not report a treatment-effect estimate or an inferential analysis for the primary endpoint.

The antibody endpoint measures an immune response, not whether adenomas recurred or progressed, or whether colorectal cancer developed. Those outcomes are part of the broader rationale described in the registry, but their results are not reported in the registry record. An immune-response measure should not be treated as proof of a prevention effect.

The safety entry reports 0 participants with serious adverse events among 39 at risk, and 39 participants with other adverse events among 39 at risk. The listing does not provide detailed event descriptions, and deaths are not reported in the registry record. These entries offer limited descriptive information; they do not establish whether events were caused by the vaccine or characterize the full safety profile.

In general, a study result is more informative when the endpoint definition, analysis population, observed estimate, and uncertainty are all available. Here, the registry record gives the endpoint description and some enrollment and safety details, but not the primary result, its denominator, or the statistical analysis. Interpretation should remain within those limits.

14. Why This Trial Matters Statistically

This trial illustrates why the clinical question and the measured endpoint need to be distinguished. The stated development goal concerns preventing adenomas from recurring or advancing, while the primary endpoint is an antibody response at 52 weeks. The endpoint addresses immune response, but it is not itself a direct measure of polyp recurrence, progression, or colorectal cancer.

The single-group design also illustrates the difference between observing an outcome and estimating a comparative effect. A study without a control group can describe outcomes among its participants if those results are reported, but it does not directly establish what would have happened under a different treatment or no treatment. The registry record does not report the primary outcome result, making even a descriptive response estimate unavailable.

Enrollment and outcome denominators are not interchangeable. The record gives enrollment of 46 and states that 6 people who consented did not receive vaccine. It does not report how many participants had an evaluable antibody measurement at 52 weeks. This leaves a key element of a response count—the population assessed—unclear in the registry record.

The safety entries further show why counts need context. The record lists participants at risk and affected for serious and other adverse events, but provides limited event detail and does not report deaths. Counts can communicate the scope of recorded events, but they do not by themselves resolve event type, timing, causality, or completeness of follow-up.

Statistically, the record is a useful example of the limits of registry descriptions without posted outcome analyses. The design, endpoint, enrollment information, and selected safety counts can be identified, while effect estimates, uncertainty, analysis populations, and missing-data methods remain unreported. These distinctions are essential when explaining what a clinical study can and cannot support.

15. 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 interpretation is that the registry record does not report the primary antibody result. It also does not report the number of participants assessed at 52 weeks, the endpoint classification rule, or an estimate of uncertainty. Consequently, neither the observed response count nor its precision can be evaluated.

The single-group design has no control group and is not a randomized comparison. Any reported outcome would therefore lack a direct concurrent comparison for distinguishing changes associated with vaccination from other influences. The registry’s allocation field is not applicable, and masking is listed as none.

Enrollment does not identify the primary analysis population. The record states that 6 of 46 people who consented did not receive vaccine and gives their reasons, but does not report the number who completed follow-up or had an evaluable antibody measurement. The analysis population and missing-data methods are not reported in the registry record.

The endpoint is an immune-response measure rather than a clinical outcome of adenoma recurrence, progression, or colorectal cancer. Although prevention is part of the stated rationale, results for those outcomes are not reported in the registry record. The antibody response criteria and assay details are also not reported, limiting assessment of how the endpoint was defined.

Safety information is limited to participant counts. Serious adverse event terms are not listed, and deaths are not reported in the registry record. Event timing, severity, duration, and causal attribution are not reported. Finally, the registry has no analysis records, so statistical methods, multiplicity handling, and the prespecified analysis plan are not reported in the registry record.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Study of the MUC1 Peptide-Poly-ICLC Adjuvant Vaccine in Individuals With Advanced Colorectal Adenoma — NCT00773097.
• Registry record last updated 2019-01-07; status last verified 2019-01.
• Results first posted 2014-02-03.
• 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.

19. Record Summary

NCT00773097 is a completed Phase 2, single-group study of MUC1 peptide vaccine with Poly-ICLC in people with a history of advanced colorectal adenoma. Enrollment was 46; the registry lists no masking and allocation as not applicable. The study started in 2008-10, with primary completion in 2011-10.

The primary outcome was the number of participants with anti-MUC1 antibody at 52 weeks. The registry also lists autoimmune response and adverse events associated with the study agent as secondary outcomes. The antibody result and statistical analyses are not reported in the registry record.

Six people who consented did not receive vaccine, for the reasons recorded in the registry. For the MUC1 Poly-ICLC group, the safety entries list 0 participants with serious adverse events among 39 at risk and 39 participants with other adverse events among 39 at risk. Deaths are not reported in the registry record.