Ipilimumab + Nivolumab w/Thoracic Radiotherapy for Extensive-Stage Small Cell Lung Cancer: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Ipilimumab + Nivolumab w/Thoracic Radiotherapy for Extensive-Stage Small Cell Lung Cancer (NCT03043599), a na phase 1, phase 2 study. The primary outcome is Phase I: Confirmation of Recommended Phase II Dose.

2. Clinical Question

These objectives address different questions. The Phase I safety run-in is described as a way to confirm a dose for the later phase among participants receiving the combined treatment after chemotherapy. The Phase II objective focuses on the proportion of participants who remain alive without progression at the specified follow-up landmark. A dose-confirmation outcome is not itself an estimate of tumor control, and a progression-free-survival estimate would not by itself establish what would have occurred under another treatment strategy.

Because the study has no concurrent comparator group, its clinical question is descriptive: what dose and outcomes were observed among participants treated according to this study approach? A single-group result cannot isolate the contribution of radiotherapy, ipilimumab, nivolumab, or their sequence from other influences. The registry record does not report an outcome estimate for either objective, so the planned questions should not be mistaken for results.

3. Trial Design

The registry record describes a Phase I and Phase II study with a single-group model. Allocation is listed as not applicable, and masking is listed as none. The record reports enrollment of 21 and status as completed. The study start date is 2017-02-13, and the primary completion date is 2018-10-26. Those registry entries describe the trial record; they do not establish how many participants contributed data to each analysis.

The treatment strategy is described as consolidative ipilimumab and nivolumab with thoracic radiotherapy after platinum-based chemotherapy. The brief summary specifies 4-6 cycles of chemotherapy and radiotherapy of 30 Gy in 10 fractions. The arm description states that radiotherapy was followed by a 14 to 21 day break before study drug treatment began. The interventions listed are thoracic radiation therapy, ipilimumab, and nivolumab.

The Phase I portion is characterized as a safety run-in intended to confirm the recommended Phase II dose. Its registered primary outcome is expressed as a number, with a unit of mg/kg dose and a 13-week timeframe. The description says investigators would initially enroll 6 patients and wait until completion of the safety observation period following initiation of combination treatment. The registry record does not report the dose selected or the results of that observation.

The Phase II portion is described as estimating the 6-month progression-free survival rate. Overall survival is listed as a secondary outcome. The record lists three outcome measures but zero analyses. It does not report whether the planned Phase II estimate was calculated, how follow-up was handled, or which participants were included in an analysis. The absence of a randomized control arm means that any reported outcomes would describe this treated group rather than a randomized treatment contrast.

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

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 Phase I: Confirmation of Recommended Phase II Dose, measured over 13 weeks.

The registered primary outcome is “Phase I: Confirmation of Recommended Phase II Dose.” It is recorded as a number, uses mg/kg dose as its unit, and has a 13-week timeframe. The accompanying description frames the Phase I portion as a safety run-in among participants receiving thoracic radiotherapy followed by ipilimumab and nivolumab after platinum-based chemotherapy. The goal is to confirm a dose for the Phase II portion. The registry record does not report the selected dose or a numerical endpoint result.

In general, a dose-confirmation outcome in an early-phase study concerns whether a candidate dose is suitable to carry forward under the study’s safety observations. It is distinct from an outcome measuring disease control or survival. The registry’s Phase II objective is to estimate the 6-month progression-free survival rate, while overall survival is listed as a secondary outcome. These are clinically different outcomes: progression-free survival concerns time without documented progression or death, whereas overall survival concerns time until death from any cause. The record does not provide the operational definitions, event assessments, or estimates for those outcomes.

The 13-week timeframe attached to the Phase I primary outcome should not be read as the follow-up period for the Phase II progression-free-survival objective. Nor does the stated Phase II objective establish that a 6-month rate was observed or reported. The registry record describes objectives and outcome measures, but does not report outcome analyses.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a single-group study with Phase I and Phase II portions. It does not report a statistical analysis plan, analysis methods, or analysis results. The explanations below are general statistical context, not a description of methods confirmed to have been used in this trial.

What does a single-group design allow?

In a single-group study, outcomes are described among participants receiving the study strategy. With no concurrent comparison arm, the analysis does not estimate a randomized difference between treatments. A count or rate in the treated group can summarize what was observed in that group, but it cannot by itself show what would have happened to comparable participants receiving another strategy. This distinction is important for both survival outcomes and adverse events.

The record lists allocation as not applicable and masking as none. It does not describe random assignment or blinded outcome assessment. Those design features should not be inferred from the Phase I/Phase II labels. The record also does not explain whether any additional allocation or assessment procedures were used.

How should a dose-confirmation outcome be understood?

In general, early-phase dose evaluation uses safety observations to inform selection of a dose for further study. The registered Phase I outcome is a number expressed in mg/kg dose, with a 13-week timeframe. Its description refers to a safety observation period after combination treatment begins. The record does not give the selected dose, rules for dose selection, criteria for classifying safety events, or a numerical result. It therefore cannot be used to reconstruct how a dose decision was made.

The Phase I objective and the Phase II objective are not interchangeable. Dose confirmation concerns the dose intended for subsequent study; the Phase II objective concerns the 6-month progression-free survival rate. The record does not report whether or how the Phase I result informed treatment in the Phase II portion.

What would a survival analysis generally require?

General explanation: time-to-event outcomes use both whether an event occurred and the time until that event. Participants who have not had an event by the end of observation may contribute partial follow-up rather than a known event time; survival methods account for this through censoring. A survival estimate can depend on the event definition, follow-up schedule, censoring rules, and analysis population. The registry record does not report these details for progression-free survival or overall survival.

A rate at a specified landmark, such as the stated 6-month progression-free-survival objective, summarizes survival status at that time point under the chosen event definition and analysis method. It does not describe every feature of the time-to-event pattern. Interpretation also depends on how progression was assessed and how participants without complete follow-up were handled. These operational details are not reported in the registry record.

A confidence interval is, in general, a way to express uncertainty around an estimate. It reflects sampling variability under the method’s assumptions; it does not correct for bias from study design or incomplete outcome ascertainment. The record does not report a progression-free-survival estimate or its interval, so neither the level nor the precision of that outcome can be assessed from the registry information.

What do the safety counts represent?

General explanation: adverse-event counts describe recorded events or participants with events, depending on the outcome definition. A count of participants with at least one event differs from a count of all event episodes, because one participant may experience more than one event. The safety entries list participants at risk and participants affected for serious and other adverse events, along with deaths. The record does not explain event coding rules, attribution, severity grading, or whether recurrent events were counted separately.

In general, event percentages in a single group are descriptive. They do not estimate excess risk relative to a control group. An apparent event frequency can also be influenced by the length and completeness of safety follow-up and by how events were solicited and classified. Those details are not reported in the registry record, so the listed counts and terms should be read as registry summaries rather than as a complete causal assessment.

What does the lack of analysis details mean?

The record lists three outcome measures and zero analyses. It does not identify an analysis population, a missing-data strategy, a statistical model, or an approach to multiplicity. Those omissions prevent readers from checking whether an analysis followed a prespecified plan or how uncertainty was calculated. They also prevent reconstruction of an endpoint estimate from the registry description alone.

General statistical explanation: when a study has multiple outcomes, researchers need to distinguish the primary question from secondary and exploratory questions. If many hypotheses are tested, the chance of at least one apparently unusual result can increase. Prespecified outcome priorities and multiplicity procedures can help readers interpret collections of tests, but the record does not report such procedures. No method should be assumed from the study’s phase or its listed objectives.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists three outcome measures, including the Phase I dose-confirmation outcome and overall survival as a secondary outcome, and describes the Phase II objective of estimating 6-month progression-free survival. It lists zero analyses. The record does not report how the primary, secondary, or Phase II objectives were prioritized in the final analyses, whether other outcomes were analyzed, or whether any multiplicity procedure was used.

In general, multiplicity matters when investigators examine several outcomes or make several statistical comparisons. Without a prespecified approach, a reader may have difficulty distinguishing confirmatory findings from exploratory observations. That general concern does not imply that any particular analysis was conducted in this study; the analysis details are not reported in the registry record.

Missing-data methods and analysis populations are also not reported in the registry record. The enrollment entry of 21 does not establish the number included in an outcome analysis. The record does not state how many participants had complete follow-up, how incomplete follow-up was handled, or whether any participants were excluded from an analysis. For time-to-event outcomes, the rules for censoring and the handling of missing event assessments can affect interpretation. For safety outcomes, the length and completeness of observation can influence which events are captured.

These omissions limit reproducibility and make it difficult to judge whether the outcome data were analyzed as planned. They do not establish that data were missing or that multiplicity adjustments were required; those details are simply 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 0% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: neoplasms benign, malignant and unspecified -other (33.3%), lung infection (28.6%), death (23.8%), diarrhea (19.0%), copd exacerbation (9.5%).

The registry lists one Combination Therapy group. Serious adverse events were reported for 13 of 21 participants at risk. Other adverse events were reported for 21 of 21 participants at risk, and deaths were reported for 6 participants. These are descriptive registry counts; the record does not provide a comparator group or a causal assessment linking events to a particular intervention.

The listed serious-event terms and percentages are Neoplasms benign, malignant and unspecified -Other (33.3%), Lung Infection (28.6%), Death (23.8%), Diarrhea (19.0%), COPD Exacerbation (9.5%), and Hyponatremia (9.5%). These percentages should be read as registry summaries for the listed terms. The record does not specify whether they represent participants with at least one event, all event episodes, or a particular event-attribution category.

The listed Death term and the separate deaths count should not be treated as evidence that study treatment caused those deaths. The registry record does not report attribution, timing, event definitions, or a comparison of rates. Safety counts also depend on the amount and completeness of observation. These details are not reported in the registry record, so the figures describe recorded safety information but do not establish comparative risk.

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

The registry record describes a completed single-group trial of consolidative ipilimumab and nivolumab with thoracic radiotherapy after platinum-based chemotherapy for extensive-stage small cell lung cancer. It records a Phase I dose-confirmation objective and a Phase II objective to estimate 6-month progression-free survival. It also lists overall survival as a secondary outcome and reports selected safety counts.

Those entries describe the study’s aims and recorded safety information; they are not numerical efficacy results. The registry record does not report the recommended Phase II dose, a progression-free-survival estimate, an overall-survival estimate, or analyses of those outcomes. It therefore does not establish the observed magnitude or precision of the planned clinical outcomes. The completed status and enrollment entry do not substitute for those missing results.

Even if descriptive outcomes were available, the single-group design would limit interpretation. A treated-group outcome cannot, on its own, determine how outcomes would differ under another treatment strategy. Without a concurrent control group, differences attributable to treatment cannot be separated from differences in participant characteristics, disease course, prior therapy, subsequent care, or other influences. This is a design limitation, not a claim about the direction of any result.

The safety counts likewise do not establish comparative risk or causation. Serious adverse events, other adverse events, deaths, and listed event terms are reported for the treatment group, but the registry does not provide the context needed to attribute events to a particular component or compare their frequency with another group. No medical conclusion about the treatment should be drawn from these registry entries alone.

The most defensible interpretation is narrow: the registry records the trial’s design, treatment sequence, objectives, enrollment, status, and safety summaries. It does not report the analyses needed to answer the numerical outcome questions. Readers seeking estimates, uncertainty intervals, or detailed analysis methods would need information not reported in the registry record.

13. Why This Trial Matters Statistically

This trial is statistically notable for bringing together an early-phase dose-confirmation objective and a later-phase clinical outcome objective within a single-group study. The distinction matters because a dose selected through safety observation answers a different question from an estimate of progression-free survival. The registry record describes both aims, but does not report their numerical results or analyses.

The treatment sequence is also central to interpreting the study question. Participants were described as receiving thoracic radiotherapy after platinum-based chemotherapy, with a break before ipilimumab and nivolumab. The registry therefore describes a treatment strategy with multiple components and a specified sequence. In a single-group design, outcomes cannot be assigned separately to radiotherapy, either study drug, the sequence, or other aspects of care.

Statistically, the absence of a concurrent comparator changes what can be learned. A single-arm study can describe outcomes and safety observations in its participants, but it cannot provide a randomized estimate of the difference from another strategy. The distinction between descriptive observation and comparative evidence is particularly important when the registry states an outcome objective but does not post an estimate, interval, or analysis method.

The record also illustrates why registry objectives and registry results should be read separately. A stated goal to estimate a 6-month progression-free-survival rate does not show that an estimate was reported. Likewise, a completed study status does not supply endpoint results. The registry lists three outcome measures and zero analyses, leaving important questions about outcome definitions, follow-up, analysis populations, and missing data unanswered.

These features make the record useful for understanding the design and its limits, while also defining what cannot be inferred from it. The design and objectives are explicit; the clinical outcome analyses are not reported in the registry record.

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.

Several limitations are specific to the available registry record. It identifies a single-group study with no masking and no separate comparator arm. Accordingly, the record cannot support a randomized treatment contrast. Any descriptive outcome from the group would also be difficult to separate from the effects of prior chemotherapy, the natural course of disease, or other care.

The treatment strategy combines thoracic radiotherapy with ipilimumab and nivolumab after platinum-based chemotherapy. A single group receiving the combined sequence cannot identify the contribution of each component. The record describes a 14 to 21 day break between radiotherapy and study drug treatment, but does not report whether treatment delivery or adherence varied among participants.

The registry reports enrollment of 21, but does not report the analysis populations, participant flow, follow-up completeness, or endpoint-specific denominators. It does not provide a Phase I dose result, a Phase II progression-free-survival estimate, or an overall-survival estimate. The methods for progression assessment, event attribution, censoring, and missing data are not reported in the registry record.

Safety interpretation is also limited by the absence of a comparison group and by missing detail about event definitions, attribution, timing, and observation. The listed counts and percentages therefore should not be interpreted as comparative or causal estimates. Finally, the record does not report the statistical analysis plan or any multiplicity approach, making it impossible to assess whether analyses followed prespecified procedures. These limitations concern what the registry record reports and do not establish what may appear in other records.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Ipilimumab + Nivolumab w/Thoracic Radiotherapy for Extensive-Stage Small Cell Lung Cancer — NCT03043599.
• Registry record last updated 2024-12-20; status last verified 2024-12.
• Results first posted 2019-10-11.
• 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

NCT03043599 is a completed Phase I/Phase II, single-group study sponsored by H. Lee Moffitt Cancer Center and Research Institute. The registry reports enrollment of 21, a start date of 2017-02-13, and a primary completion date of 2018-10-26. The study concerns consolidative ipilimumab and nivolumab with thoracic radiotherapy after platinum-based chemotherapy for extensive-stage small cell lung cancer.

The Phase I primary outcome concerns confirmation of the recommended Phase II dose over a 13-week safety observation period. The Phase II objective is to estimate the 6-month progression-free-survival rate; overall survival is listed as a secondary outcome. The registry lists three outcome measures and zero analyses. It reports safety counts for serious and other adverse events and deaths, but does not report the primary dose result or clinical outcome estimates. Allocation is listed as not applicable, and masking as none.