Immunologic Effects of CDX-301 and CDX-1140 in Resectable Pancreatic Cancer Patients: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Immunologic Effects of CDX-301 and CDX-1140 in Resectable Pancreatic Cancer Patients (NCT04536077), a randomized phase 2 study. The primary outcome is Amount of Intratumoral Conventional Dendritic Cells (cDCs).

2. Clinical Question

3. Trial Design

This was a randomized, open-label, parallel-group Phase 2 trial sponsored by Washington University School of Medicine. Its title describes testing the immunologic effects of CDX-301 and CDX-1140 in patients with resectable pancreatic cancer. The registry record lists pancreatic cancer and related condition descriptions. It reports enrollment of 16 and a terminated status. The start date is 2021-08-13, and the primary completion date is 2023-11-21. The reason for termination is not reported in the registry record.

The two arms differed in whether participants received CDX-301 before CDX-1140. In the monotherapy arm, participants received one intravenous CDX-1140 infusion at 1.5 mg/kg. In the combination arm, participants received CDX-301 at 75 mcg/kg/day by subcutaneous injection on Days 1-5, then CDX-1140 at 1.5 mg/kg intravenously on Day 8, with a plus-or-minus 1-day window. Surgery was to follow CDX-1140 administration by 7-12 days in both arms. The registry record also lists a research blood draw as an intervention.

The primary endpoint was assessed at surgery, estimated to occur between day 8 and day 20. Although enrollment was 16, the posted endpoint summaries contain 4 participants in each arm. The endpoint description says that participants were excluded from the overall number analyzed when there was insufficient tumor for additional analysis or the tumor was small. The registry record does not explain the disposition of all enrolled participants or provide a participant flow account.

Randomization does not by itself establish how allocation was implemented. The sequence-generation method, allocation concealment, and any stratification factors are not reported in the registry record. Masking is listed as none. The protocol's statistical plan, sample-size justification, and any interim analyses are also not reported in the registry record.

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.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Participants were not included in the overall number of participants analyzed if there was insufficient tumor for additional analysis or small tumor size.

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 Amount of Intratumoral Conventional Dendritic Cells (cDCs), measured over At time of surgery (estimated to be between day 8 and day 20).

The primary endpoint is the amount of intratumoral conventional dendritic cells (cDCs), expressed as a percentage of total cells. It is recorded as a mean with standard deviation and is assessed at surgery, estimated to occur between day 8 and day 20. The posted arm summaries give the mean and standard deviation for the tissue samples included in each arm's endpoint analysis.

In general, a cell percentage describes the share of cells in a specified sample that belong to a particular cell category. Here, the measure focuses on conventional dendritic cells within tumor tissue, rather than a blood measurement or a clinical outcome such as survival. The registry's central hypothesis concerns an immunologic effect of adding CDX-301 to CDX-1140, so a tumor immune-cell measure addresses that stated research question.

A mean summarizes the measured values in an arm, while the standard deviation describes how spread out those values are around the mean. Neither statistic alone conveys the precision of the between-arm comparison. The registry record does not report confidence intervals for this endpoint, nor does it provide a statistical analysis of the arm contrast. The reason for selecting this particular cell population as the primary endpoint beyond the stated immunologic objective is not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The posted primary outcome is continuous: each observation is a percentage, and the registry reports a mean and standard deviation for each arm. The reported analysis summaries are descriptive. No between-arm inferential analysis is listed in the registry record, and the record does not report a confidence interval or p-value for the primary endpoint.

What does the mean describe?

In general, the mean is the arithmetic average of the observed measurements in a group. For this trial, it summarizes the intratumoral cDC percentage among participants included in the endpoint analysis. An arm mean does not show the full distribution of individual measurements. Different sets of observations can produce the same mean, and a mean can be influenced by unusually high or low values. Individual participant measurements and distribution plots are not reported in the registry record.

What does the standard deviation describe?

In general, the standard deviation describes the dispersion of measurements around their mean, in the same units as the measurements. Here, that unit is percentage of total cells. Greater spread means the observed values are more dispersed around the group mean; it does not directly quantify uncertainty in the mean or in the difference between arms. A standard error or confidence interval would address precision more directly, but neither is reported for this outcome in the registry record.

With a small analyzed group, the observed spread and mean may be strongly affected by individual observations. That is a general feature of estimates based on limited data, not evidence about what happened to any particular participant in this trial. The registry record does not include participant-level values, so the degree of skew, the presence of outliers, and the shape of the endpoint distribution cannot be evaluated from the posted summaries.

How should a between-arm comparison be assessed?

In general, a between-arm estimate quantifies the contrast in endpoint values, while a confidence interval communicates the range of values reasonably compatible with the data and analysis assumptions. A p-value, when used, addresses compatibility with a specified null model; it does not describe the size or clinical importance of an effect. None of these inferential quantities is posted for the primary endpoint. The registry record does not report an adjusted or unadjusted treatment-effect estimate or a statistical test.

For a continuous endpoint, a statistical comparison would need to account for the endpoint's scale and the assumptions of the chosen model. In general, the variability and distribution of the measurements matter. The registry record does not state whether any distributional checks, transformations, covariate adjustments, or robust methods were planned or used. Those details should not be inferred from the descriptive mean and standard deviation.

Why can over-dispersion matter?

In general, over-dispersion means that variation in the observed data is greater than a statistical model expects. If a model assumes less variability than the data contain, standard errors can be too small and uncertainty can be understated. This concept is relevant when selecting or assessing a model, but the posted summaries do not establish whether over-dispersion was present in this endpoint. The registry record does not report a model or diagnostic assessment for the primary outcome.

Randomization is intended to support a fair comparison between assigned groups, but it does not eliminate uncertainty, missing outcome data, or problems arising from small analyzed groups. In this trial, the endpoint analysis includes fewer participants per arm than the overall enrollment. The endpoint description identifies tumor tissue availability and size as reasons for exclusion, but the registry does not state whether those exclusions were related to treatment assignment or endpoint values. The potential effect of those exclusions on the comparison cannot be quantified from the posted summaries.

What is reported about analysis planning?

The registry record does not report the statistical analysis plan, the sample-size justification, a prespecified method for comparing the arms, or interim analyses. A planning illustration based on an observed effect would not be an observed trial result or evidence of the trial's power; any such sample-size estimates are planning quantities. The posted record does not provide a recalculated between-arm comparison for this continuous endpoint, because values needed for that comparison are marked as missing or not estimable. No planning figure should be interpreted as a property of the participants' observed outcomes.

In general, a well-described statistical report identifies the target population, analysis set, handling of missing observations, model, effect estimate, uncertainty interval, and any multiplicity adjustment. Those details help readers understand what a result estimates and how dependent it is on assumptions. For this trial, the endpoint definition and exclusion note are available, but the broader analysis details are not reported in the registry record. Interpretation should therefore remain at the level of the posted arm summaries and the limits they impose.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("CDX-1140 Monotherapy", "CDX-1140 + CDX-301")
n   <- c(4, 4)
m   <- c(0.9615, 2.631)
sp  <- c(0.3699, 0.8024)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  CDX-1140 Monotherapy  4  0.962  0.370  0.373  1.550
CARM  CDX-1140 + CDX-301  4  2.631  0.802  1.354  3.908

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists one primary outcome measure and no secondary outcomes posted. It reports no analyses. The multiplicity approach is not reported in the registry record. With no posted inferential tests, there is no stated adjustment for multiple testing to evaluate. The existence of a single listed primary endpoint does not establish what analyses may have been planned or conducted outside the posted record.

The primary outcome description states that participants were not included in the overall number analyzed if there was insufficient tumor for additional analysis or if the tumor was small. The endpoint summaries include 4 participants in each arm, whereas the adverse event summaries list 7 at risk in each arm. These are outcome-specific counts; they should not be combined or treated as the same analysis population. The registry record does not explain why the counts differ or provide a detailed flow of participants from enrollment through endpoint assessment.

Missing-data methods are not reported in the registry record. It does not state whether missing endpoint values were imputed, whether participants with unavailable tissue were excluded from all analyses, or whether sensitivity analyses were performed. The record also does not give enough detail to assess whether tissue availability or tumor size could have affected the arm comparison. The primary endpoint results should therefore be read as summaries of the analyzed tissue observations, not necessarily as summaries of everyone enrolled or randomized.

Analysis population definitions beyond the endpoint's stated exclusion are not reported in the registry record. The record does not specify whether the primary endpoint analysis followed an intention-to-treat principle or another defined approach. It also does not report a protocol-level statistical plan or a rationale for the number enrolled.

12. 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 serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: nausea (14.3%), vomiting (14.3%), flu like symptoms (14.3%), disease progression (14.3%), pneumonitis (14.3%).

The registry record reports serious adverse event counts for participants listed as at risk in each arm. In the monotherapy arm, 7 were at risk for serious adverse events and 1 was affected. In the combination arm, 7 were at risk and 3 were affected. These are counts as posted, not an adjusted comparison. The record does not provide a statistical analysis of the difference or enough detail to determine the timing, duration, or relationship of the events to study treatment.

For other adverse events, the record lists 7 at risk and 7 affected in each arm. Death counts are 2 in the monotherapy arm and 3 in the combination arm. The registry record does not provide information in these summaries about causes of death, timing, or attribution. Counts alone do not show whether events were related to treatment.

The listed serious adverse event terms are nausea, vomiting, flu like symptoms, disease progression, and pneumonitis, each reported as 14.3%. The registry record does not specify in this listing how those terms are distributed across the arms or whether the percentages represent participants or event occurrences. These figures should be read as posted event summaries, not as evidence that one regimen caused a particular event or that the arms differ in safety.

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

The primary result is a descriptive comparison of intratumoral cDC percentages at surgery. The posted means are higher in the CDX-1140 plus CDX-301 arm than in the CDX-1140 monotherapy arm. The registry reports a combination-arm mean of 2.631% of total cells and reports a mean and standard deviation for each arm. The endpoint summaries are based on 4 participants per arm. No confidence interval, p-value, or formal between-arm analysis is reported in the registry record.

This result is an observation about an immunologic endpoint in tumor tissue. It does not, by itself, demonstrate a change in tumor size, disease progression, survival, or another clinical outcome. The registry's central hypothesis concerns anti-tumor immunity, but the posted primary measure is the amount of one category of immune cell as a percentage of total cells. A difference in this measure cannot by itself establish the broader biological or clinical consequences of treatment.

The findings also do not establish whether the observed contrast is precise or likely to be reproduced. The analyzed group is small, individual values are unavailable, and the record does not report an inferential comparison. The stated exclusions for insufficient tumor tissue or small tumor size may limit how directly the endpoint summaries represent all enrolled participants. Missing-data handling and the analysis population are not described in detail.

The serious adverse event summaries are counts in separate outcome populations, not a direct comparison of treatment-related risk. The record lists affected participants, participants at risk, other adverse events, deaths, and serious event terms, but does not provide sufficient detail about timing, attribution, or event distribution by arm for the listed terms. These summaries should not be interpreted as establishing causation.

The trial's terminated status is part of the registry record, but the reason is not reported. It should not be used to infer why the study ended or to explain the posted results. Overall, the record supports a description of the endpoint and safety summaries, while leaving substantial uncertainty about precision, missing data, analysis methods, and the clinical meaning of the observed immune-cell difference.

14. Why This Trial Matters Statistically

This trial is statistically notable because its primary question is framed around an immunologic measure rather than a direct clinical outcome. The endpoint expresses intratumoral conventional dendritic cells as a percentage of total cells at surgery. That creates a quantitative comparison between randomized arms, while keeping the interpretation specific to tumor tissue and the cell population measured. It is important not to extend that measure to outcomes that were not reported.

The posted endpoint summaries also illustrate why analyzed counts and enrollment totals are not interchangeable. The record reports enrollment of 16, but the primary endpoint summaries include 4 participants in each arm, and the adverse event summaries list 7 at risk in each arm. Each count belongs to its stated outcome context. The reason the endpoint counts are lower is partly described through the tissue sufficiency and tumor-size exclusion note, but a complete participant flow and explanation of the outcome-specific counts are not reported.

Statistical interpretation depends not only on the direction of the group means but also on variability, precision, and the analysis plan. The registry gives means and standard deviations but no interval estimate or inferential test for the primary comparison. It therefore offers limited information for judging how uncertain the contrast is. The absence of posted analysis details also prevents readers from assessing modeling choices, missing-data procedures, or any adjustment for multiple comparisons.

The trial highlights the difference between a biologically motivated endpoint and evidence of a clinical effect. A measured difference in an immune-cell percentage can address the stated immunologic question, but the record does not report evidence that connects this endpoint to clinical benefit. Careful statistical reporting would make that boundary clear while documenting how the endpoint population was formed and how uncertainty was quantified.

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 primary endpoint analysis is based on 4 participants in each arm, despite an overall enrollment of 16. The endpoint description states that participants could be excluded from the overall number analyzed because of insufficient tumor for additional analysis or small tumor size. The registry record does not provide a full participant flow, identify the disposition of every participant, or explain the difference between the endpoint and safety counts.

Only descriptive endpoint summaries are posted. There is no reported confidence interval, p-value, treatment-effect estimate, or statistical model for the arm comparison. Without these, the precision of the observed difference cannot be assessed from the registry record. Individual participant observations are also not reported, limiting assessment of distribution shape, outliers, and variability within arms.

The registry record does not report the method for random sequence generation or allocation concealment. It lists the trial as open-label, and does not provide a statistical analysis plan, sample-size justification, interim analysis information, missing-data method, or analysis population definition beyond the tissue-related exclusion note. The reason for termination is not reported. The primary endpoint is an immunologic measure at surgery, so the posted result does not answer questions about clinical outcomes that are not reported as endpoints.

Safety summaries provide counts and listed event terms, but do not state event timing, treatment attribution, causes of death, or the arm distribution of the listed serious event terms. These limitations constrain comparisons between arms and interpretation of the safety findings.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Immunologic Effects of CDX-301 and CDX-1140 in Resectable Pancreatic Cancer Patients — NCT04536077.
• Registry record last updated 2024-10-08; status last verified 2024-09.
• Results first posted 2024-10-08.
• 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

NCT04536077 is a randomized, open-label, parallel-group Phase 2 trial sponsored by Washington University School of Medicine. It studied CDX-1140 monotherapy versus CDX-1140 with CDX-301 in resectable pancreatic cancer. The registry record reports enrollment of 16, a start date of 2021-08-13, a primary completion date of 2023-11-21, and terminated status. The reason for termination is not reported.

The primary endpoint was the mean percentage of intratumoral conventional dendritic cells at surgery, estimated between day 8 and day 20. The posted summaries include 4 participants per arm. The mean is higher in the combination arm, but no inferential comparison or confidence interval is reported. The endpoint description notes exclusions for insufficient tumor tissue or small tumor size.

Serious adverse event summaries list 7 participants at risk in each arm, with 1 affected in the monotherapy arm and 3 in the combination arm. The record also lists other adverse events, deaths, and serious event terms without enough detail to establish causation. Statistical planning and analysis methods are not reported in the registry record.