Interleukin-2 in Metastatic Kidney Cancer: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Interleukin-2 in Metastatic Kidney Cancer (NCT01702909), a na phase 2 study. The primary outcome is Number of Participants With Response Using RECIST Criteria.

2. Clinical Question

The study record lists an enrollment of 7 and a status of terminated. Its primary completion date is 2014-12. Those entries describe the registry record, but do not supply a participant-level account of enrollment, treatment, follow-up, or response. The distinction matters: a stated objective and a defined endpoint describe what the study sought to evaluate, not what its results demonstrated.

Median duration of response and median survival are listed as secondary outcomes. Their inclusion indicates additional questions about the duration of tumor response and survival, but no estimates or analysis results for these outcomes are reported in the registry record. The clinical question can therefore be described from the protocol-style endpoint wording, while the answer based on observed outcomes remains unavailable in the record.

3. Trial Design

This was a phase II, single-group study of interleukin-2 in metastatic kidney cancer. The registry record identifies Western Regional Medical Center as the sponsor. The listed enrollment is 7. The study started in 2012-09, had a primary completion date of 2014-12, and is marked terminated. These registry entries describe the planned and recorded study status; they do not establish how many participants received treatment or completed follow-up.

The study had no separate control arm: the model is single-group and allocation is listed as NA. Masking is listed as none. Thus, the design is not a randomized comparison and does not support a like-for-like treatment contrast. Any response observed in a single group would need to be interpreted as an outcome among treated participants, rather than as an effect estimated by comparison with a concurrent control group.

The intervention is named as interleukin-2, and the official title describes moderate dose bolus interleukin-2. The registry record does not report the dose details or a complete administration schedule. Its brief summary states that the study aimed to determine whether the dose and schedule used would help increase tumor shrinkage. That purpose should not be confused with a result.

The primary endpoint was the number of participants with response using RECIST criteria. Radiographic studies were described as occurring after every 2 cycles (6 weeks), until disease progression or death from any cause up to 2 years. The primary outcome record also states that no data was collected. The registry record lists Median Duration of Response and Median Survival as secondary outcomes, but does not report their results. It lists 3 outcome measures and 0 analyses. The statistical analysis plan, participant flow, reasons for termination, and detailed follow-up information are 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

Analysis population for the primary outcome, as defined in the registry: No data was collected

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 Response Using RECIST Criteria, measured over Measured until Disease Progression or death from any cause up to 2 year.

The primary endpoint is the number of participants with response using RECIST criteria. It is a tumor-response endpoint based on radiographic assessment rather than a direct measure of survival or symptoms. The record describes RECIST v1.0 assessment of target lesions using CT scans. Complete response means disappearance of all target lesions; partial response means a >=30% decrease in the sum of the longest diameter of target lesions. The record defines overall response rate using complete and partial responses among participants receiving interleukin-2.

Response criteria offer a standardized way to classify change in measurable tumors. Using a prespecified threshold can make radiographic response assessments more consistent than relying on an informal judgment that a tumor has shrunk. Repeated imaging can also identify whether a response is observed during the stated follow-up period. These are general features of a response endpoint; they do not establish that assessments were completed or that response occurred in this study.

The registry record says radiographic assessments were performed after every 2 cycles (6 weeks), until disease progression or death from any cause up to 2 years. It also states “No data was collected” for the primary outcome population. No response count or response rate is reported in the registry record. Consequently, the endpoint is defined, but its observed value cannot be interpreted from the recorded outcome information. The registry record also does not provide details on independent review, handling of unevaluable scans, or the analysis population used to calculate response.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The study is classified as phase II and single-group. These labels describe the study stage and comparison structure; they do not, by themselves, specify a statistical analysis. The record lists allocation as NA and masking as none. Because there is no separate control group, the study does not estimate a treatment contrast between randomized groups. Any valid interpretation of an observed response would concern the treated group and would require appropriate outcome data, which are not reported for the primary endpoint.

What does a response endpoint represent?

The primary endpoint counts participants meeting response criteria. The registry record describes RECIST v1.0 for target lesions assessed by CT scan. Complete response is defined as disappearance of all target lesions; partial response is defined as a >=30% decrease in the sum of the longest diameter of target lesions. The record describes overall response rate as the proportion based on complete and partial responses among participants receiving interleukin-2. This is a binary classification at the participant level: each participant is classified according to whether the response criteria are met.

As a general statistical matter, a response proportion is interpretable only alongside the number assessed and the rules for handling missing or unevaluable assessments. A confidence interval can express uncertainty around an estimated proportion, with wider intervals generally indicating less precision. No response estimate, confidence interval, or analysis population is reported in the registry record, so no interval can be interpreted for this trial.

Why does the assessment schedule matter?

The record describes radiographic studies after every 2 cycles (6 weeks), until disease progression or death from any cause up to 2 years. A schedule defines when measurements were intended to be collected and can affect which responses are detected. In general, assessment timing, missed scans, and the definition of the response window can influence an endpoint. The record does not report whether the intended assessments occurred, how missed assessments were handled, or whether response was confirmed by repeat imaging.

What can a single-group design estimate?

In general, a single-group study can describe the outcomes observed among treated participants, if those outcomes are collected and analyzed. It cannot directly estimate what would have happened to comparable participants under a different intervention or without the study treatment. A randomized control group can help distinguish treatment-related differences from other influences; this study has no such group. Historical or external comparisons may be informative in some settings, but they require assumptions about comparability that are not established in this record.

What is the role of sample-size planning?

Sample-size calculations are planning tools: they describe the number of participants that might be needed under stated assumptions to detect a specified effect with a chosen level of statistical power. They do not measure the probability that a completed study’s result is correct. The registry record’s planning assumptions describe a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of the observed effect. Those assumptions are illustrations, not the design of this single-group trial. They do not establish that the study was planned with a control arm, and no numerical planning result is reported in the registry record.

When a sample-size illustration is based on an observed effect, it is conditional on that effect estimate and should not be described as observed power. The record does not report an observed primary effect estimate, and the primary outcome population is marked as having no data collected. Therefore, the assumptions alone cannot provide a trial-specific basis for evaluating precision or adequacy of enrollment.

What analysis details are unavailable?

The registry record lists 0 analyses. It does not report a statistical analysis plan, an estimated response proportion, a confidence interval, a hypothesis test, or handling of missing outcome data. The record also does not specify a population definition for the primary analysis beyond the statement that no data was collected. Without these details and results, readers cannot reproduce an outcome analysis or determine how the endpoint was operationalized in practice.

General statistical interpretation should distinguish a prespecified measurement rule from an estimated result. RECIST criteria and an imaging schedule identify what was intended to be measured. They do not supply evidence that a response occurred, nor do they determine the precision of a response estimate. For this record, the method is described more fully than the outcome analysis, and the reported primary outcome information is insufficient to estimate response.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists 3 outcome measures, including the primary response endpoint and the secondary outcomes Median Duration of Response and Median Survival. It does not report a statistical analysis plan, a hierarchy among secondary outcomes, or a strategy for controlling the chance of false-positive findings across multiple outcomes. Multiplicity procedures and planned testing rules are therefore not reported in the registry record. No inferential results are reported for which multiplicity adjustment could be assessed.

The record lists 0 analyses, and the primary outcome population is described as having no data collected. It does not explain whether data were missing, whether measurements were not obtained, or whether outcomes were collected but not entered. Those possibilities have different implications and cannot be distinguished from the registry record. Missing-data methods, rules for unevaluable scans, and the treatment of participants who discontinued are not reported in the registry record.

The analysis population is also not described. Although the listed enrollment is 7, the record does not say how many participants received treatment or were eligible for each outcome analysis. It does not state whether analyses were intended to include all enrolled participants, only treated participants, or only participants with evaluable assessments. Such population definitions can affect interpretation, particularly for a response endpoint that depends on imaging assessments.

In general, multiple outcomes and incomplete follow-up can complicate interpretation because the reported estimate may depend on which outcomes and participants are included. Here, the absence of analyses and outcome estimates means there is no basis to evaluate those issues empirically. The reasons for termination and any changes to outcomes or analysis plans are not reported in the registry record.

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 5% reporting threshold.

Most frequent non-serious adverse event terms

The registry safety listing reports 7 participants at risk for serious adverse events and 0 affected. For other adverse events, it reports 7 at risk and 7 affected. It also reports 7 deaths. These are counts recorded for the adverse-events group; they are not a comparison between treatment arms, because the study is single-group.

The zero serious-event count should be read as the registry’s reported count, not as proof that no serious event could have occurred outside the recorded data. The record does not list serious adverse-event terms, timing, severity details, or the method used to collect or classify events. The list of top serious terms is empty. The distinction between “serious” and “other” adverse events is a classification distinction, not a measure of whether an event was caused by treatment.

The death count is not accompanied by a cause, timing, attribution, or participant-level description. The registry record does not establish whether deaths were related to treatment, disease progression, or another cause. Counts alone also do not provide event rates over person-time or describe when events occurred. Because there is no control group, these figures cannot estimate a comparative safety effect.

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

The record establishes that a phase II, single-group study of interleukin-2 in metastatic kidney cancer was registered, with a RECIST-based response endpoint and a stated imaging schedule. It also records an enrollment of 7, a terminated status, and listed secondary outcomes of Median Duration of Response and Median Survival. These details describe the study’s design and intended questions.

The record does not establish the observed response. The primary endpoint population is marked “No data was collected,” and no response count or rate is reported. No results for duration of response or survival are reported either. Consequently, the registry information cannot show whether tumor shrinkage occurred, how often it occurred, how long any response lasted, or what survival was observed.

Nor does this record estimate a causal effect of interleukin-2. The study has no control group, so it does not compare outcomes with a concurrent group receiving another treatment or no study treatment. Even if outcome estimates were available, interpretation would be limited to what a single-group design can establish. General factors such as participant selection, disease course, and follow-up can affect outcomes and cannot be separated from treatment effects through a control comparison that this design does not include.

The safety counts should also be interpreted descriptively. The registry reports 0 serious adverse events, 7 other adverse events, and 7 deaths, but does not report event details or causal attribution. Those figures do not establish why deaths occurred or whether events were caused by treatment.

Thus, the primary statistical conclusion is about the limits of the recorded evidence: the endpoint is defined, but its outcome is not reported. The study’s objective is not itself evidence of benefit or lack of benefit. A missing estimate is not a zero response estimate, and it should not be interpreted as demonstrating that an effect was absent.

13. Why This Trial Matters Statistically

This trial matters statistically because it illustrates the difference between a well-defined endpoint and a reported result. The registry describes a RECIST response measure, including radiographic assessment and response criteria, but the primary outcome population is recorded as having no data collected. Without an observed response count or estimate, the central clinical question cannot be answered from the registry record.

The single-group design also clarifies what study structure can and cannot establish. A treated-group outcome can be described when data are available, but without a control group there is no direct estimate of how outcomes differ from an alternative. This is not a flaw unique to this record; it is a general limit of interpretation for studies without a concurrent comparison group. It is especially important not to mistake the study objective for a treatment effect.

The registry’s status of terminated and its listed enrollment of 7 provide useful context, but they do not explain why the study ended or how many participants had evaluable outcomes. The reasons for termination and the analysis population are not reported. The safety counts are also limited to descriptive tallies without event terms or attribution.

Finally, the record demonstrates why reporting includes more than naming an endpoint. Readers need outcome estimates, denominators, uncertainty measures, analysis populations, and information about missing data to judge the evidence. Here, the registry records the intended response question but not the data needed to estimate its answer. That distinction prevents unsupported conclusions in either direction.

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 primary limitation specific to this study record is the absence of collected primary outcome data: the population field for the response endpoint says “No data was collected.” The registry record therefore does not provide a response count, response rate, or uncertainty estimate. It also reports 0 analyses, leaving no analytical results to evaluate or reproduce.

The design is single-group, with allocation listed as NA and masking as none. There is no concurrent comparator, so the record cannot support a direct comparative treatment-effect estimate. The listed enrollment of 7 does not reveal the number treated, assessed, or included in an analysis. Participant flow and analysis-population definitions are not reported in the registry record.

Although the response criteria and imaging schedule are described, the record does not say whether scans were completed as planned, how unevaluable or missed assessments were handled, or whether response required confirmation. The reason for the terminated status is not reported. It is also not reported whether there were changes to the planned study procedures or outcome definitions.

Secondary outcomes include Median Duration of Response and Median Survival, but no estimates or follow-up details are reported. For safety, the record gives counts but no serious-event terms, event timing, death causes, or treatment attribution. These omissions limit both benefit and harm interpretation. The record does not provide enough information to determine whether missing outcomes reflect uncollected assessments, incomplete reporting, or another circumstance.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Interleukin-2 in Metastatic Kidney Cancer — NCT01702909.
• Registry record last updated 2018-02-08; status last verified 2018-02.
• Results first posted 2017-09-27.
• 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

NCT01702909 is a phase II, single-group study titled “Interleukin-2 in Metastatic Kidney Cancer.” Western Regional Medical Center is listed as sponsor. The intervention is interleukin-2; allocation is NA, masking is none, and the study status is terminated. Listed enrollment is 7. The study started in 2012-09 and has a primary completion date of 2014-12.

The primary endpoint is the number of participants with response using RECIST criteria. The registry describes radiographic assessments after every 2 cycles (6 weeks), until disease progression or death from any cause up to 2 years, but states that no data was collected for the primary outcome population. Median Duration of Response and Median Survival are listed as secondary outcomes. The registry lists 3 outcome measures and 0 analyses.

The adverse-event listing reports 0 serious adverse events, 7 participants with other adverse events, and 7 deaths. Event details, causes, and attribution are not reported in the registry record. The available information describes the study design and intended measures but does not provide primary efficacy results.