This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for A Study of Sunitinib In Young Patients With Advanced Gastrointestinal Stromal Tumor (NCT01396148), a non-randomized phase 2 study. The primary outcome is Estimated Steady-State Maximum Plasma Concentration (Cmax,ss) of Sunitinib and Its Metabolite.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01396148 |
| Phase | Phase 2 |
| Condition | Gastrointestinal Stromal Tumors |
| Allocation | Non-Randomized |
| Design model | Not Stated |
| Masking | None (open label) |
| Enrollment | 6 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Pfizer |
| Results posted | Yes |
2. Clinical Question
Population
Children and young adults with gastrointestinal stromal tumors (GIST) were eligible. The registry describes a children’s group as ages 6 years to <18 years and a young-adult group as ages 18 years to <21 years. The study enrolled 6 participants. Its stated focus was advanced GIST in these age groups.
Intervention
The interventions listed are sunitinib malate dose escalation and sunitinib malate. The study description says participants would be treated with sunitinib. Its stated aims included assessing safety, pharmacokinetics and tolerability, as well as tumor responses and overall survival. The registry record does not report the dosing schedule or how dose escalation was implemented.
Comparator
This was a nonrandomized study with no masking. The registry record does not describe a control treatment or a randomized comparison. The listed age groups should not be read as equivalent treatment and control arms: without random allocation and a stated control group, differences between groups would not isolate a treatment effect.
Primary question
The primary endpoint was estimated steady-state maximum plasma concentration (Cmax,ss) of sunitinib and its metabolite SU012662. It summarizes drug concentrations across stated sampling times in the first three cycles and several post-dose times on Day 1 of Cycle 1. This is a pharmacokinetic question about drug exposure, not a direct measure of tumor response or survival. The registry record does not report the endpoint’s numerical results.
3. Trial Design
The registry identifies this as a completed phase 2 study, while the official title calls it a phase I/II study. It was nonrandomized and unmasked. The registry lists an enrollment of 6 and describes children and young adults with GIST as the study population. Its intervention listings are sunitinib malate dose escalation and sunitinib malate. The record does not explain how participants were assigned to these interventions, whether all participants received both, or how dosing differed by age group.
The age-group descriptions are children ages 6 years to <18 years and young adults ages 18 years to <21 years. These descriptions identify the intended groups, but the registry record does not report how many participants were enrolled in each group. Since allocation was not randomized and no control treatment is described, the groups do not constitute a like-for-like treatment comparison.
The study description identifies safety, pharmacokinetics and tolerability as aims, with tumor responses and overall survival also to be assessed. The registered primary endpoint is estimated steady-state maximum plasma concentration of sunitinib and SU012662. Listed secondary outcomes cover adverse events, laboratory abnormalities, objective response, duration of response, progression-free survival and overall survival. The record lists 22 outcome measures and 0 analyses. These registry entries describe the study’s intended scope; they do not provide numerical findings for the primary endpoint or the listed secondary outcomes.
The registry gives a start date of 2012-06, a primary completion date of 2017-08 and a completed status. It does not report a detailed protocol, a sample-size justification, an interim-analysis plan or the statistical analysis plan. The record’s absence of those details means that design choices should not be inferred from the outcome labels or from the study title.
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
| Stage | Sunitinib |
|---|---|
| STARTED | 6 |
| COMPLETED | 5 |
| NOT COMPLETED | 1 |
Reasons for not completing this period:
| Reason | Sunitinib |
|---|---|
| Patient Decision | 1 |
Analysis population for the primary outcome, as defined in the registry: The PK population included all treated participants with at least one PK observation.
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: The full analysis set (FAS) included all enrolled participants regardless of what treatment, if any, was received.
| Characteristic | Unit | Sunitinib |
|---|---|---|
| Participants analysed | 6 | |
| Age, Continuous | years | 14.3 (SD 1.4) |
| Sex: Female, Male: Female | Participants | 5 |
| Sex: Female, Male: Male | Participants | 1 |
| Race/Ethnicity, Customized: White | participants | 5 |
| Race/Ethnicity, Customized: Asian | participants | 1 |
6. Primary Endpoint
The registry lists the primary outcome as Estimated Steady-State Maximum Plasma Concentration (Cmax,ss) of Sunitinib and Its Metabolite, measured over pre-dose on Day 1, Day 12-18 and Day 25-29 of Cycle 1,2, 3 and 2, 4, 6, 8 hours post-dose on Day 1 Cycle 1.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | nanograms per milliliter (ng/mL) |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is estimated steady-state maximum plasma concentration (Cmax,ss), measured in nanograms per milliliter (ng/mL), for sunitinib and its metabolite SU012662. A maximum plasma concentration describes the highest concentration observed or estimated in blood after dosing. The steady-state qualifier refers, in general pharmacokinetic usage, to exposure after concentrations have approached a repeating pattern across doses. The registry describes the endpoint as an estimate and specifies the mean and standard deviation as its summary statistics.
The stated sampling schedule includes pre-dose measurements on Day 1, Day 12-18 and Day 25-29 of Cycle 1, 2 and 3, as well as measurements 2, 4, 6 and 8 hours post-dose on Day 1 of Cycle 1. The description says summarized data for all time points was reported. This endpoint is used to characterize drug exposure and its variability in the study population. It is a pharmacokinetic measure, not itself an assessment of tumor shrinkage, disease progression, survival or tolerability.
The PK population includes all treated participants with at least one PK observation. The registry record does not report the numerical mean or standard deviation, the number with usable measurements, or how estimates were derived from the observations. It therefore does not support a numerical interpretation of the primary endpoint or a comparison of exposure between age groups.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a pharmacokinetic primary endpoint but does not report its numerical result. In particular, no mean or standard deviation for Cmax,ss is stated. Without those estimates, readers cannot determine the reported concentration level, the observed dispersion, or whether exposure differed between children and young adults. The record’s description of the endpoint and collection schedule tells readers what was intended to be measured, not what the measurements showed.
The study enrolled 6 participants and was nonrandomized. These registry entries place important limits on interpretation: the record does not establish a randomized comparison, and the listed age groups are not a control group. Any differences by age, if reported elsewhere, could reflect participant or treatment differences rather than age alone. The registry record does not report group-specific results or an analysis of between-group differences.
The record lists safety, tolerability, tumor response and survival among the study aims or outcomes. It does not report numerical results for objective response, duration of response, progression-free survival or overall survival. The adverse-event summary reports 0 serious adverse events and 0 deaths among the stated group, alongside 6 participants with other adverse events. Those figures describe the registry’s recorded safety categories; they do not provide detail about event types, severity distributions, timing or treatment attribution for each event.
A mean is a measure of the central value of observations, while a standard deviation describes their spread. In general, the standard deviation is not a measure of uncertainty in the estimated mean. A confidence interval, if reported, would help express uncertainty in an estimate; the registry record does not report a confidence interval for the primary endpoint. Nor does it report a formal hypothesis test for the primary endpoint. Thus, no claim about statistical significance or precision of the pharmacokinetic estimate can be drawn from the information recorded.
The entry of 0 analyses does not mean that no analyses were performed in the study. It means the registry record contains no analyses in that registry field. Likewise, the absence of a numerical endpoint result in this record should not be interpreted as evidence that no data were collected. It means the posted record does not document those results. Conclusions should be limited to the study design, endpoint definitions and adverse-event counts that are actually recorded.
9. Statistical Methods Explained
The primary measure is continuous: each recorded concentration is a numerical quantity on a concentration scale. The registry specifies that Cmax,ss is summarized by a mean and standard deviation. In general, a mean combines observed values into a central summary, while the standard deviation describes how spread out the observations are around that mean. Neither statistic alone shows the full distribution. With a small study population, individual observations can have a substantial influence on the mean, and the standard deviation may itself be imprecisely estimated.
What does the pharmacokinetic endpoint summarize?
Cmax is the maximum plasma concentration, and the “ss” notation denotes a steady-state measure. Pharmacokinetic measures are used to describe how a drug is present in the body over time. The listed sampling schedule includes pre-dose observations on specified days across cycles and several post-dose observations on Day 1 of Cycle 1. The endpoint description says summarized data for all time points was reported. The registry record does not explain the estimation procedure used to derive Cmax,ss from the sampling data, so the precise computational method cannot be reconstructed from this entry.
The PK population is defined as treated participants with at least one PK observation. This definition sets an analysis population based on treatment and data availability; it does not mean every treated participant necessarily contributed measurements at every scheduled time. The record does not state how missing or unusable concentrations were handled, whether any observations were excluded, or how many participants contributed to the primary summary. A population definition is not a substitute for a missing-data method.
How should uncertainty be understood?
General statistical interpretation distinguishes variability among participants from uncertainty about an estimated quantity. The standard deviation describes dispersion in the observed concentrations. A confidence interval would describe a range of values compatible with the data under a specified statistical method and assumptions. No confidence interval is reported in the registry record for the primary endpoint, and no standard error or hypothesis test is given. The record therefore does not support a formal assessment of precision beyond identifying the planned summary statistics.
For repeated concentration measurements, observations from the same participant are generally related rather than independent. General pharmacokinetic analyses may account for repeated measurements and the timing of collection, but the registry record does not describe a model or other estimation procedure. It is not possible to determine from the entry whether participant-level dependence, deviations from scheduled times, or other aspects of the sampling process were incorporated into the reported estimate.
What can the listed outcome measures establish?
The record lists secondary outcomes covering treatment-emergent and treatment-related adverse events, serious adverse events, clinically significant laboratory abnormalities, objective response, duration of response, progression-free survival and overall survival. These outcomes answer different questions. Adverse-event counts describe the number of participants meeting an event definition; response outcomes describe tumor status under specified criteria; time-to-event outcomes concern the time until an event or censoring. The record does not provide numerical results for most of these outcomes, nor does it specify the analysis methods, response criteria or censoring rules in this entry.
For time-to-event outcomes, general methods may account for participants whose event has not been observed by the end of follow-up. Such observations are commonly treated as censored, and interpretation depends on the follow-up and censoring assumptions. The registry record does not report the follow-up distribution, censoring details or survival-analysis method. No survival estimate can therefore be interpreted from the listed outcome names alone.
What do the planning assumptions mean?
The registry’s planning illustration is described as based on an observed effect, with two-sided significance level 0.05, equal allocation between two arms and a normal approximation. It says that the effect to detect is a stated fraction of the observed effect, and that time-to-event planning uses a total number of events while other planning gives participants per arm. Such calculations are prospective planning illustrations, not observed study outcomes and not evidence of the probability that the completed study detected an effect.
The record explicitly distinguishes those planning assumptions from the trial’s own design. In particular, equal allocation in a planning illustration does not establish that this nonrandomized study assigned participants equally, or that its age groups were comparable. The registry record does not provide the observed effect used in that illustration, a trial-specific sample-size justification or a statistical analysis plan. Consequently, the illustration cannot be used to infer the trial’s intended power or to interpret the absence of a reported result.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 22 outcome measures spanning pharmacokinetics, safety, tumor response and survival. When a study considers multiple outcomes or multiple comparisons, general statistical practice may address multiplicity: the chance of false-positive findings can increase when many statistical tests are conducted. Methods such as prespecifying a primary outcome, adjusting significance thresholds or describing findings as exploratory can help readers understand that risk. The registry record does not report a multiplicity procedure or explain how the listed outcomes were prioritized beyond identifying the primary endpoint.
The entry lists 0 analyses. This registry entry does not provide inferential analysis results, test statistics, confidence intervals or p-values for the primary or secondary outcomes. It also does not report whether outcomes were changed, added or omitted after study initiation. Such information is not reported in the registry record, so readers cannot assess the relationship between any analyses and a prespecified statistical plan.
For the primary endpoint, the PK population includes treated participants with at least one PK observation. This is the only explicit analysis-population definition in the endpoint description. The registry record does not report how missing measurements, incomplete sampling schedules, withdrawals or protocol deviations were handled. It also does not state whether all enrolled participants were treated or whether the PK population included every treated participant.
Missingness can affect both the amount and the representativeness of available data. In general, an analysis based only on observed measurements may be biased if the chance of a measurement being missing is related to the concentration or participant characteristics. The record does not describe missing-data assumptions or sensitivity analyses. These omissions limit assessment of the robustness of the estimates, but do not establish that data were missing or that a particular method was used.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Sunitinib | 0 | 6 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Sunitinib | 0 of 6 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Sunitinib | 6 of 6 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Sunitinib |
|---|---|---|
| Headache | Nervous system disorders | 4 of 6 |
| Neutropenia | Blood and lymphatic system disorders | 3 of 6 |
| Diarrhoea | Gastrointestinal disorders | 3 of 6 |
| Nausea | Gastrointestinal disorders | 3 of 6 |
| White blood cell count decreased | Investigations | 3 of 6 |
| Anaemia | Blood and lymphatic system disorders | 2 of 6 |
| Thrombocytopenia | Blood and lymphatic system disorders | 2 of 6 |
| Dyspepsia | Gastrointestinal disorders | 2 of 6 |
| Decreased appetite | Metabolism and nutrition disorders | 2 of 6 |
| Back pain | Musculoskeletal and connective tissue disorders | 2 of 6 |
The registry’s safety summary lists a Sunitinib group with 6 participants at risk for serious adverse events, 0 with serious adverse events, 6 at risk for other adverse events and 6 with other adverse events. It also records 0 deaths. These are counts in the registry’s categories; they do not describe the specific adverse-event terms or how many events each participant experienced.
A count of participants with an event is different from a count of events. One participant may experience more than one event, while a participant-level count records whether the specified category occurred. The registry record does not provide a list of serious-event terms in this summary. It also does not give event timing, duration, severity distribution or a detailed account of causal attribution. The secondary outcomes include treatment-emergent and treatment-related adverse events and events at least Grade 3, but the numerical results for those outcomes are not reported in this entry.
Zero recorded serious adverse events and zero deaths describe the recorded counts; they do not establish that the risk of such events is absent. In general, safety estimates from a small study can be imprecise, and a count alone cannot characterize the range of possible risks. These registry figures should be read as descriptive safety information, not as a comparative estimate, because the study was nonrandomized and no control group is described.
12. What the Result Does, and Does Not, Mean
The registry record documents a completed, nonrandomized phase 2 study of sunitinib in children and young adults with GIST. It identifies an estimated steady-state maximum plasma concentration of sunitinib and SU012662 as the primary endpoint and defines the PK population as treated participants with at least one PK observation. It also records a small enrollment and provides limited safety counts. These registry entries describe the design and the available registry summary, not the full set of study findings.
The primary endpoint’s mean and standard deviation are not reported in the registry record. Without numerical concentration estimates or an uncertainty measure, readers cannot assess the observed exposure level or its precision. The record also does not report numerical results for the listed tumor response and survival outcomes. Consequently, the endpoint definitions and study aims alone cannot establish what was observed for pharmacokinetics, response or survival.
The safety summary records 6 participants with other adverse events, 0 with serious adverse events and 0 deaths in the listed Sunitinib group. Those counts do not provide a comprehensive characterization of event types, timing or severity, and they are not a comparison with another treatment. A zero count within a study does not show that an event cannot occur outside the study or that risk is absent.
The nonrandomized design and lack of a described control group limit causal interpretation. The age groups should not be treated as randomized treatment arms, and the record does not report group-specific results that would allow an age comparison. More broadly, the registry record does not report the analysis plan, handling of missing data, or inferential results. Statistical conclusions should therefore remain confined to the recorded design, outcome definitions and descriptive counts rather than claims about comparative effects or clinical benefit.
13. Why This Trial Matters Statistically
This study is statistically notable because it focuses on pharmacokinetic measurement in children and young adults with GIST, while also listing safety, response and survival outcomes. Drug-concentration data address exposure and variability, questions that differ from whether tumors respond or how long participants remain free of progression. Keeping these estimands separate helps prevent a pharmacokinetic endpoint from being interpreted as a clinical outcome.
The registry’s age-defined groups also illustrate why design matters when interpreting subgroup information. Children and young adults are described separately, but allocation is nonrandomized and no control treatment is recorded. Comparisons across those groups, if available elsewhere, would not by themselves isolate the effect of age or treatment. Clear group-specific estimates, participant counts and methods would be needed to assess how informative such comparisons are.
The record further illustrates the distinction between an outcome being planned and its results being available in a registry entry. It lists 22 outcome measures but 0 analyses, and it provides no numerical primary pharmacokinetic result. Readers therefore need to distinguish the stated endpoint and measurement schedule from quantitative evidence about the endpoint. Reporting estimates with suitable measures of uncertainty and explaining analysis populations and missing-data handling are important for transparent interpretation.
Finally, the recorded safety counts are descriptive rather than comparative. The absence of recorded serious events in a small, nonrandomized study cannot by itself provide a precise characterization of safety. The entry is useful for identifying the questions addressed and the limitations of the available summary, while also showing why detailed results and methods are essential to statistical interpretation.
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 main limitation of the registry record is that it does not report numerical results for the primary pharmacokinetic endpoint. Although the endpoint and its mean-and-standard-deviation summary are specified, no concentration estimate, dispersion estimate or confidence interval is recorded. The description therefore supports understanding of the intended measurement but not interpretation of the observed exposure.
The study enrolled 6 participants and was nonrandomized. The record does not describe a control treatment or randomized assignment, and the age groups cannot be treated as like-for-like controls. The numbers enrolled in each age group and their group-specific outcomes are not reported in this entry. This limits assessment of any age-related pattern and rules out a controlled comparison based on the registry information alone.
Detailed treatment and measurement procedures are also not reported. The registry lists dose escalation and sunitinib malate, but does not explain dosing, assignment to the listed interventions, adherence or changes in treatment. It provides a sampling schedule but does not describe the method used to estimate Cmax,ss or how incomplete sampling was handled.
The entry does not report a statistical analysis plan, sample-size justification, interim-analysis plan, multiplicity approach, missing-data method or survival-analysis details. It lists secondary outcomes but supplies no numerical results for response, progression-free survival or overall survival. Safety reporting is limited to participant counts and does not give the event terms or a detailed account of severity, timing or attribution. These gaps are limitations of the registry record and should not be taken to establish that the underlying study did not collect or analyze those data.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Study of Sunitinib In Young Patients With Advanced Gastrointestinal Stromal Tumor — NCT01396148.
- Registry record last updated 2019-03-27; status last verified 2019-03.
- Results first posted 2018-03-12.
- 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.
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18. Record Summary
The registry identifies a completed, nonrandomized phase 2 study of sunitinib in children and young adults with advanced GIST. The official title describes it as a phase I/II study. Enrollment is recorded as 6, and the listed age groups are children ages 6 years to <18 years and young adults ages 18 years to <21 years.
The primary endpoint is estimated steady-state maximum plasma concentration of sunitinib and its metabolite SU012662, summarized by mean and standard deviation. The PK population comprises treated participants with at least one PK observation. Secondary outcomes include adverse events, laboratory abnormalities, objective response, duration of response, progression-free survival and overall survival.
The safety summary records 0 serious adverse events and 0 deaths, with 6 participants in the other adverse-event category. The registry lists 22 outcome measures and 0 analyses, and does not report the numerical primary endpoint result or numerical results for the listed response and survival outcomes. The record gives a start date of 2012-06, a primary completion date of 2017-08 and completed status.