RX-3117 in Combination With Abraxane® in Subjects With Metastatic Pancreatic Cancer: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for RX-3117 in Combination With Abraxane® in Subjects With Metastatic Pancreatic Cancer (NCT03189914), a na phase 1, phase 2 study. The primary outcome is Number of Participants With Treatment-related Adverse Events as Assessed by CTCAE v4.0 (Phase 1 and 2).

2. Clinical Question

The central statistical question is therefore descriptive: what safety information does the registry report for participants receiving the combination, and how much can that information establish about treatment-related adverse events? The record lists 46 participants enrolled and separates posted adverse-event information into a Phase 1 group and a Phase 2 group. Those groups received the same named combination, but their different study phases do not make them randomized comparison groups.

The study also lists pharmacokinetic outcomes for RX-3117 and several clinical outcomes, including overall response rate, time to response, duration of response, progression-free survival, and time to progression. These outcomes indicate the range of questions the study registered, but their results are not reported in the information available in the registry record. The study design and listed endpoints do not, by themselves, establish comparative efficacy or a treatment effect.

3. Trial Design

The registry lists NCT03189914 as a completed Phase 1/2 study of RX-3117 in combination with Abraxane® for metastatic pancreatic cancer. Its title describes an open-label study of safety, pharmacokinetics, pharmacodynamics, and efficacy. The brief summary describes a Phase 1b/2a, multicenter, two-stage study: a dose-finding Phase 1 portion followed by a two-stage Phase 2a portion. The Phase 2a portion is described as using the combination as first-line therapy.

The registered model is single-group, masking is none, and allocation is NA. There is no separate control group. Consequently, the Phase 1 and Phase 2 groups are not randomized arms that can be interpreted as a controlled comparison. The study description gives an RX-3117 dosing range of 500 - 700 mg/ day for 5 days on/ 2 days off for 3 weeks, with 1 washout week per cycle. Abraxane is described as 75 - 125 mg/m\^2 once per week for 3 weeks, with 1 washout week per cycle.

The registry reports enrollment of 46, a start date of 2017-10-02, a primary completion date of 2019-10-01, and completed status. It lists 26 outcome measures and no analysis entries. The primary outcome is the number of participants with treatment-related adverse events assessed using CTCAE v4.0 over 9 months. Listed secondary outcomes include RX-3117 exposure measures, overall response rate, time to response, duration of response, progression-free survival, and time to progression.

The registry record does not report the sample-size justification, detailed statistical plan, analysis populations, or any interim-analysis plan. The stated two-stage description is part of the study summary; further operational details are not reported in the registry record. The two phases and their posted safety counts should therefore be read as descriptive study information, not as evidence from a randomized comparison.

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: Phase 1: The arm was designed as a dose de-escalation. De-escalation was not required during Phase 1, therefore, the starting dose 700mg RX-3117 + 125 mg/m\^2 Abraxane was the only dose tested.

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 Number of Participants With Treatment-related Adverse Events as Assessed by CTCAE v4.0 (Phase 1 and 2), measured over 9 months.

The primary endpoint is the number of participants with treatment-related adverse events assessed using CTCAE v4.0. Its timeframe is 9 months. In plain terms, the endpoint is a participant count: it concerns how many participants experienced at least one event judged treatment-related, rather than the total number of event episodes or a measure of event severity alone. The registry’s description specifies treatment-related adverse events, while the posted serious adverse-event information is reported separately; those measures should not be treated as interchangeable.

Safety is an important focus in a study combining a drug being evaluated with another treatment. Counting affected participants gives a direct descriptive account of how many people had the specified outcome during the defined observation period. In general, a count can be easier to interpret when the population at risk and the event definition are clear. The registry identifies CTCAE v4.0 as the assessment framework and gives a 9-month timeframe, but the primary endpoint result itself is not reported in the registry record.

Without the endpoint count and its analysis details, the record does not show the observed frequency of the primary outcome, its precision, or how the outcome was handled if participants had incomplete follow-up. The endpoint definition also does not establish a causal relationship by itself: treatment-relatedness is an assessment, and the study has no separate control group for comparison. Thus the endpoint is relevant to describing safety, but the posted registry information is insufficient to quantify its primary result or make a controlled comparison.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The study is registered as a single-group, open-label Phase 1/2 study. These design features matter for statistical interpretation. A single-group design observes outcomes among people receiving the study regimen but does not create a randomized comparison with a control treatment. Open-label means the study is not masked according to the registry. General statistical principle: masking can affect how outcomes are assessed or reported, especially when judgments are involved; the registry does not quantify any such effect in this study.

What does a participant count represent?

The primary endpoint is a count of participants who experienced a treatment-related adverse event, assessed using CTCAE v4.0 over 9 months. The unit is participants, so the endpoint concerns people meeting the event definition rather than the number of event episodes. General statistical principle: when outcomes are recorded as whether each participant did or did not experience an event, the count can be related to a proportion only when the relevant denominator and analysis population are defined. The record identifies the endpoint unit and timeframe but does not report the primary endpoint result or the analysis population used for it.

Event counts also depend on how events are defined, attributed, collected, and followed. Here, the registry describes the endpoint as treatment-related and names CTCAE v4.0. It does not report further adjudication procedures, missing-outcome handling, or details about whether repeated events contribute to the primary measure. Those details are not reported in the registry record and should not be inferred from the endpoint title.

Why does the single-group design limit comparisons?

In a randomized controlled trial, random allocation is used to make treatment groups comparable on average, allowing a between-group contrast to support an estimate of relative effect under the study conditions. This record lists allocation as NA and the model as single-group. The Phase 1 and Phase 2 groups are phases of one study, not a randomized treatment and control pair. Their counts can be described separately, but a difference between them would not isolate a treatment effect. Differences could reflect factors that are not reported, including the characteristics of participants or the conduct of the phases; no particular explanation can be selected from this record.

General statistical principle: uncertainty in a count or estimated event frequency is important, especially when the number of observed participants is limited. A confidence interval expresses a range of values compatible with the data under a statistical model. It does not guarantee that the true value lies in that range, and it does not correct design limitations such as a lack of a control group. No confidence interval for the primary endpoint is reported in the registry record.

What can be learned from the adverse-event summaries?

The registry reports serious adverse-event counts and other adverse-event counts separately for the Phase 1 and Phase 2 groups, along with deaths. These are descriptive safety summaries. The serious adverse-event figures identify how many participants in each group are listed as affected; the listed serious-event terms and percentages provide additional descriptive detail. They do not supply a causal comparison or a complete account of the primary treatment-related adverse-event endpoint. Serious adverse events and all treatment-related adverse events are distinct categories in the information reported, and the primary endpoint result is absent.

General statistical principle: an event percentage is most informative when its numerator, denominator, event definition, and observation period are clear. Percentages can be unstable when based on limited observations, and a percentage alone does not convey uncertainty. The record does not provide inferential estimates for the listed serious-event terms. Their reported percentages should not be converted into comparative claims about the two phases.

How should the planning illustrations be understood?

The sample-size illustrations use assumptions stated as a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect to detect expressed as a fraction of the observed effect. For time-to-event outcomes, the stated planning quantity is total events; for other outcomes, it is participants per arm. These are planning illustrations computed from an observed effect, not the trial’s own design justification. They are not observed power and do not show that this single-group study was powered for a controlled comparison. The registry record does not report the trial’s own sample-size justification or the observed effect used in those illustrations.

General statistical principle: power is a design calculation about the chance of detecting a prespecified effect under assumptions. It is not a measure of how likely a treatment is to be effective, and retrospective calculations based on an observed effect do not replace a prospective design rationale. Because the registry does not report a two-arm randomized comparison, the assumptions in those planning illustrations should not be read as a description of the actual study design.

What is not reported about the statistical plan?

The registry lists 26 outcome measures and no analysis entries. It does not report which statistical models were used, how estimates were adjusted, how incomplete observations were handled, or what analysis populations were defined. It also does not report an interim-analysis plan. These omissions prevent a detailed assessment of endpoint-specific analysis choices or the precision of the reported safety summaries. General statistical principle: methods should be matched to the outcome type and study design, and interpretation should account for uncertainty, missing data, and the number of outcomes examined. The available record does not provide enough analysis detail to determine how those issues were addressed.

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("RX-3117 + Abraxane Phase 1", "RX-3117 + Abraxane Phase 2")
n      <- c(8, 38)
events <- c(8, 38)
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  RX-3117 + Abraxane Phase 1  8  8  100.0  63.1  100.0  67.6  100.0  66.4  99.7
ARM  RX-3117 + Abraxane Phase 2  38  38  100.0  90.7  100.0  90.8  100.0  91.0  99.9

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 26 outcome measures, including the primary treatment-related adverse-event count and secondary pharmacokinetic, response, and time-to-event outcomes. It reports no analysis entries. A multiplicity-adjustment strategy, such as a plan for controlling the chance of false-positive findings across several statistical tests, is not reported in the registry record. The record also does not report which outcomes were designated for formal hypothesis testing, so the listed measures should not be treated as a set of confirmed statistical findings.

Missing-data methods are not reported in the registry record. This includes how incomplete follow-up, unavailable outcome assessments, or withdrawal from the study were handled in the primary endpoint analysis. The analysis population or populations are also not reported. Enrollment is reported as 46, but the registry information does not establish which participants contributed to each endpoint analysis or whether all enrolled participants were included in every outcome summary.

These gaps matter because outcome estimates depend on the population analyzed and on how missing observations are addressed. General statistical principle: excluding participants with incomplete data can affect an estimate if their outcomes differ from those observed, while different assumptions about missing outcomes can lead to different results. No particular missing-data method or analysis population can be inferred. The primary endpoint result itself is not reported in the registry record, so its precision and sensitivity to missing data cannot be assessed.

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 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: febrile neutropenia (12.5%), anaemia (12.5%), hyperbilirubinaemia (12.5%), embolism (12.5%), small intestinal obstruction (5.3%).

The registry reports serious adverse-event information separately for the RX-3117 + Abraxane Phase 1 and Phase 2 groups. In Phase 1, the group at risk is 8, with 3 participants listed as having serious adverse events; other adverse events are listed for 8 of 8 participants, and deaths are listed as 0. In Phase 2, the group at risk is 38, with 18 participants listed as having serious adverse events; other adverse events are listed for 38 of 38 participants, and deaths are listed as 2.

The listed serious adverse-event terms include febrile neutropenia, anaemia, hyperbilirubinaemia, and embolism at 12.5% each, and small intestinal obstruction and acute cholecystitis at 5.3% each. These are registry-reported terms and percentages. The record does not provide further event-level context in the information available.

These figures are descriptive, not a randomized comparison. The phases are not like-for-like control groups, and the summaries do not establish that the regimen caused every listed event. The serious adverse-event counts should also not be substituted for the primary endpoint, which counts participants with treatment-related adverse events over 9 months. That primary endpoint result is not reported in the registry record.

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

The registry shows that the study was completed and that the posted record contains descriptive adverse-event information for participants receiving RX-3117 with Abraxane®. It reports serious adverse-event counts, other adverse-event counts, deaths, and selected serious-event terms with percentages for the Phase 1 and Phase 2 groups. These observations are useful as a record of what was reported for those groups, but they do not provide a controlled estimate of the regimen’s effect.

The primary safety endpoint is the number of participants with treatment-related adverse events assessed using CTCAE v4.0 over 9 months. Its result is not reported in the registry record. The registry also lists response and time-to-event outcomes, as well as pharmacokinetic outcomes, but their results are not reported in the information available. Therefore, the registry record does not establish a primary endpoint rate, comparative efficacy, or a treatment effect on the listed outcomes.

General statistical principle: a descriptive count is not a causal estimate. Without a separate control group, outcomes among participants receiving a regimen cannot show how those same participants would have fared under another treatment or without the regimen. Likewise, an absence of a reported result in the registry is not evidence that an outcome was absent; it means the result is not reported in the registry record.

The posted serious adverse-event figures should be interpreted with their group denominators and study phases in mind. They do not establish that the Phase 1 and Phase 2 groups are comparable, and differences between them would not be a randomized treatment contrast. The record does not provide confidence intervals or inferential analyses to characterize uncertainty around the safety summaries. It also does not report missing-data methods or analysis populations.

In statistical terms, the strongest supported interpretation is narrow: the record describes the design and reports certain safety counts among participants in the two study phases. It does not support a conclusion about comparative benefit, comparative harm, or the size and precision of the primary endpoint result. The study’s open-label, single-group structure and the absence of posted primary and secondary outcome analyses constrain what can be inferred.

14. Why This Trial Matters Statistically

This study is statistically notable because its registered aims span dose finding, safety, pharmacokinetics, pharmacodynamics, and efficacy, while the design is listed as open-label and single-group. Those aims involve outcomes with different statistical forms: participant counts for safety, concentration measures for pharmacokinetics, response outcomes, and time-to-event outcomes. Each requires suitable definitions and analysis choices, but the registry record does not report analysis entries or detailed methods.

The record also illustrates the difference between a study’s stated outcomes and its reported results. It lists a primary safety endpoint and multiple secondary outcomes, yet does not report the primary endpoint result or inferential outcome analyses. Outcome names alone cannot answer whether an endpoint was met, how uncertain an estimate was, or how a treatment compared with an alternative.

The Phase 1 and Phase 2 groups provide descriptive information, but they do not create a controlled comparison. This distinction is central when reading safety and efficacy evidence: observed outcomes in a treated group may be reported clearly while still leaving the treatment effect unidentified. The study’s phase structure and single-group model therefore matter as much as the numerical safety counts.

The registry’s planning illustrations also underline a design principle. Calculations based on an observed effect and hypothetical two-arm assumptions are planning exercises, not a retrospective measure of power and not evidence that the actual single-group study had a randomized comparison. Distinguishing design assumptions, observed data, and inferential claims is essential to an accurate statistical reading of a clinical trial record.

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 central design limitation is the absence of a separate control group. The registry lists a single-group model, allocation as NA, and no masking. Outcomes among participants receiving the combination can be described, but the study design does not support a like-for-like randomized treatment contrast. The Phase 1 and Phase 2 groups are study phases, not randomized comparison arms.

The registry does not report the result for the primary endpoint: the number of participants with treatment-related adverse events assessed using CTCAE v4.0 over 9 months. It also does not report results for the listed secondary outcomes or statistical analysis entries. This prevents assessment of the estimated primary outcome, its precision, and the results of the listed pharmacokinetic, response, and time-to-event measures.

Important analysis details are not reported in the registry record. These include the sample-size justification, analysis populations, missing-data methods, interim-analysis plan, and multiplicity strategy. The record does not provide enough information to assess how incomplete observations or multiple outcomes were handled. Enrollment is reported as 46, but the analysis population for each endpoint is not reported.

The posted serious adverse-event information is descriptive and does not replace the primary endpoint result. The record does not provide additional event-level context for the listed terms or inferential comparisons. The open-label design is another interpretive constraint, particularly for outcomes involving assessment or attribution; the record does not quantify any resulting effect. These limitations restrict conclusions to the study design and the specific safety counts reported.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: RX-3117 in Combination With Abraxane® in Subjects With Metastatic Pancreatic Cancer — NCT03189914.
• Registry record last updated 2023-12-06; status last verified 2023-11.
• Results first posted 2023-12-06.
• 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

NCT03189914 is a completed, open-label Phase 1/2 single-group study of RX-3117 with Abraxane® in metastatic pancreatic cancer. The registry reports enrollment of 46 and describes a dose-finding Phase 1 portion followed by a Phase 2a portion. The primary endpoint is the number of participants with treatment-related adverse events assessed using CTCAE v4.0 over 9 months.

The record reports serious adverse-event counts, other adverse-event counts, deaths, and selected serious-event terms for the Phase 1 and Phase 2 groups. It does not report the primary endpoint result, secondary outcome results, or analysis entries. The phases are not a randomized comparison, and the record does not report the statistical plan, analysis populations, missing-data methods, or sample-size justification.