A Phase II Trial of Sutent (Sunitinib; SU011248) for Recurrent Anaplastic Astrocytoma and Glioblastoma: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Phase II Trial of Sutent (Sunitinib; SU011248) for Recurrent Anaplastic Astrocytoma and Glioblastoma (NCT00606008), a na phase 2 study. The primary outcome is Number of Participants With Progression Free Survival (PFS) at 6 Months Utilizing McDonald Criteria for Response, Progression and Relapse.

2. Clinical Question

The study summary describes the purpose as examining whether sunitinib changes the cancer, slows or stops tumor growth, and is safe. Those aims are distinct from evidence of a comparative treatment effect: without a control group, the design can describe outcomes among treated participants but cannot directly estimate how those outcomes compare with what would have happened without sunitinib.

3. Trial Design

This was a Phase II, completed, single-group study sponsored by H. Lee Moffitt Cancer Center and Research Institute. The registry lists enrollment of 30 participants and the conditions as anaplastic astrocytoma and glioblastoma. The record gives a start date of 2007-03 and a primary completion date of 2012-08.

All participants were assigned to the Sutent Treatment group in the record. Sunitinib malate was administered daily for 4 weeks at a dose of 50 mg, followed by a 2 week study-drug-free break. Masking was listed as none, and allocation was recorded as NA. This is not a randomized comparison. The AA and GB cohorts are subgroups defined by diagnosis; they should not be interpreted as like-for-like treatment and control groups.

The primary endpoint is the number of participants with progression-free survival at 6 months according to McDonald criteria. The stated population for that outcome is all participants. Secondary outcomes are best overall response and the number of participants with related Grade 3 and greater adverse events. The record lists three outcome measures, but does not report their numerical results.

The registry record does not report a detailed treatment adherence plan, criteria for stopping treatment, follow-up schedule beyond the named 6-month primary timeframe, or procedures for handling treatment interruptions. A planned sample-size justification, randomization procedure, and masking procedure are not reported; the design is single-group, allocation is NA, and masking is none. The record marks the study completed, but completion status alone does not indicate whether the primary endpoint was met or what the observed outcome was.

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: Study patients were stratified by tumor histology (AAor GB).

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: All participants

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 Progression Free Survival (PFS) at 6 Months Utilizing McDonald Criteria for Response, Progression and Relapse, measured over 6 Months.

The primary endpoint is the number of participants with progression-free survival at 6 months, assessed using McDonald criteria for response, progression and relapse. It is a count of participants at a specified time, rather than a reported estimate of the time until progression. The registry gives the outcome unit as participants and defines the population as all participants.

The criteria describe complete response as disappearance of all lesions and tumor-related disease signs and symptoms. Partial response requires a 50% decrease in the sum of the longest diameters of target enhancing lesions relative to pretreatment measurements. Stable disease means neither enough shrinkage to meet partial response nor enough increase to meet progression, using the smallest sum of the longest diameter since treatment started as reference. Progression or relapse includes an increase of at least 25% in the sum of diameters of a measured enhancing lesion relative to pretreatment measurements, or new enhancing lesions.

In general, a fixed-time progression-free survival endpoint can summarize how many participants meet the study’s progression-free definition at a clinically specified assessment point. It is useful because it focuses on tumor status rather than tumor shrinkage alone. The registry record does not report the number meeting this endpoint, the handling of participants with missing assessments, or details of how deaths were incorporated into the endpoint definition. Without the observed count and its analysis, the primary endpoint’s result and precision cannot be assessed.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the endpoint count?

The primary outcome is specified as a number of participants with progression-free survival at 6 months. The endpoint is therefore a participant count at a fixed assessment time, interpreted according to the stated McDonald response, progression and relapse criteria. It is not presented as a hazard ratio or as a median time-to-event estimate. The record does not give the actual count or a statistical estimate around it.

In general, a count endpoint is a direct way to report how many people in a study meet a defined outcome. To interpret it fully, readers need the number assessed, the outcome definition, and information about missing or unevaluable observations. Here, the outcome population is described as all participants, but the registry does not report assessment completeness or missing-data handling. Thus it is not possible to determine from the record whether every enrolled participant contributed an observed endpoint assessment.

How do the response criteria work?

The registry description distinguishes complete response, partial response, stable disease, and progression or relapse. Complete response is defined by disappearance of lesions and tumor-related signs and symptoms. Partial response uses a 50% reduction in the sum of longest diameters of target enhancing lesions compared with pretreatment measurements. Stable disease is the category that meets neither the stated shrinkage threshold for partial response nor the increase threshold for progression, with the smallest sum since treatment began serving as reference. Progression or relapse includes an increase of at least 25% relative to pretreatment measurements or the appearance of new enhancing lesions.

In general, standardized response criteria make tumor assessments more reproducible by specifying how lesion changes are classified. The registry record does not report additional assessment procedures, such as who reviewed scans or whether review was independent. Those details should not be assumed.

What can a single-group design estimate?

This study is identified as single-group, with no masking and allocation recorded as NA. In general, a single-group trial can describe outcomes among participants receiving the study intervention. It does not include a concurrent control group to separate treatment-associated outcomes from the natural course of disease, other care, or differences in participant characteristics. The AA and GB cohorts are diagnostic cohorts, not control arms, and should not be treated as a randomized comparison.

For a comparative treatment question, random assignment can help balance known and unknown prognostic factors between groups. That design feature is absent. Even if outcome counts were posted, a within-study count would not by itself supply a controlled estimate of what would have happened under an alternative treatment. No comparative treatment-effect estimate is reported.

What do uncertainty measures add?

In general, a confidence interval describes the range of values reasonably compatible with data under a stated statistical model and gives readers information about precision. A p-value addresses compatibility of data with a specified null hypothesis under the model; it is not the probability that a treatment works. Neither a confidence interval nor a p-value for the primary endpoint is reported in this registry record. A count alone, even if available, would not communicate the same information about uncertainty.

The record lists no outcome analyses. It does not report a statistical model, adjustment strategy, confidence intervals, or hypothesis-testing procedure. This means the posted record does not support a reconstruction of the inferential analysis. It also does not support a claim that a result was statistically significant or not significant.

How should planning illustrations be understood?

In general, a sample-size planning illustration asks how many participants might be needed to detect an assumed effect under specified design assumptions. Such an illustration is conditional on the chosen effect and assumptions, and it is not an observed result or a measure of the trial’s actual statistical power. The registry record does not report a trial-specific sample-size justification. Any planning illustration based on an observed effect should be understood as hypothetical planning, not as observed power; it cannot substitute for the missing primary outcome result.

The record describes a binary outcome type and a participant count, but provides no numerical efficacy estimate from which to judge the size or precision of the primary result. The registered enrollment of 30 is a study characteristic, not itself evidence that the study had adequate precision or that a planned effect could be detected. The rationale for that enrollment is not reported.

Why can event counts be difficult to compare?

In general, adverse-event counts depend on how events are defined, the duration and completeness of follow-up, attribution rules, and whether the unit is participants or event occurrences. A count of participants affected is not necessarily the same as a count of distinct events, because one participant may experience more than one event. The record labels the relevant figures as participants affected, but does not give a detailed event-counting specification or the observation period for the safety summary.

Over-dispersion is a general statistical issue that can arise when event variation exceeds what a simple count model expects; in such settings, standard errors from an overly restrictive model can be too small. No count model or over-dispersion assessment is reported for this study, and no such analysis should be inferred. The posted safety counts are descriptive information, not a substitute for a specified statistical comparison.

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("Sutent Treatment", "AA Cohort Patients", "GB Cohort Patients")
n      <- c(30, 14, 16)
events <- c(4, 2, 2)
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  Sutent Treatment  30  4  13.3  3.8  30.7  5.3  29.7  5.5  29.8
ARM  AA Cohort Patients  14  2  14.3  1.8  42.8  4.0  39.9  4.3  40.5
ARM  GB Cohort Patients  16  2  12.5  1.6  38.3  3.5  36.0  3.8  36.4

11. Multiplicity, Missing Data and Analysis Populations

The record lists one primary endpoint and two secondary outcomes: best overall response, and the number of participants with related Grade 3 and greater adverse events. It does not report a statistical analysis plan or a multiplicity strategy. Multiplicity refers, in general, to the increased chance of at least one false-positive finding when several statistical hypotheses are tested. Approaches such as prioritizing outcomes or adjusting inference can address that issue, but the registry record does not say whether any such approach was planned or used.

No outcome analyses are listed, and numerical results for the primary or secondary outcomes are not reported. Therefore, there are no posted p-values or interval estimates to interpret across outcomes, and no basis to assess whether findings were adjusted for multiple testing. The record does not report interim analyses or stopping rules; neither should be inferred from the Phase II designation or the completed status.

The primary outcome population is described as all participants. The record does not provide more detail about analysis populations, exclusions, adherence requirements, or how participants with missing endpoint assessments were handled. In general, missing outcome data can affect both the count and its interpretation, especially if the likelihood of missingness is related to disease status or treatment experience. No missing-data method, imputation procedure, or sensitivity analysis is reported.

These omissions do not establish that the investigators performed no analysis or had no plan. They mean those methods are not reported in the registry record, so the statistical handling of multiple outcomes and incomplete observations cannot be evaluated from the posted information.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

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: leukocytes (total wbc) (21.4%), platelets (14.3%), rash: hand-foot skin reaction (14.3%), fatigue (asthenia, lethargy, malaise) (12.5%), lymphopenia (7.1%).

The registry safety figures list 11 of 30 participants in the Sutent Treatment group as affected in the serious-event count, and 28 of 30 in the other-event count. For the AA cohort, the corresponding figures are 6 of 14 and 14 of 14. For the GB cohort, they are 5 of 16 and 14 of 16. These are descriptive participant counts, not comparisons against an untreated or randomized control group.

The record also lists serious adverse-event terms with percentages: Leukocytes (total WBC), 21.4%; Platelets, 14.3%; Rash: hand-foot skin reaction, 14.3%; Fatigue (asthenia, lethargy, malaise), 12.5%; Lymphopenia, 7.1%; and Death not associated with CTCAE term - disease progression NOS, 7.1%. The denominator and calculation basis for these term-specific percentages are not reported. They should not be interpreted as rates among all enrolled participants without that information.

The serious-event counts are distinct from the listed secondary outcome of related Grade 3 and greater adverse events; the record does not establish that the two summaries use identical definitions. It also does not report detailed attribution criteria or exposure-adjusted rates. These figures describe what the registry lists, but do not establish that an event was caused by sunitinib.

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

The registry record establishes that a completed Phase II single-group study enrolled 30 participants with recurrent anaplastic astrocytoma or glioblastoma and evaluated sunitinib. It specifies a primary endpoint of the number with progression-free survival at 6 months under McDonald criteria, and it describes the treatment schedule and selected safety counts.

The central efficacy result is not reported in the registry record. There is no numerical count of participants with progression-free survival at 6 months, no reported best overall response result, and no reported numerical result for the secondary outcome concerning related Grade 3 and greater adverse events. Without those outcome results, the posted record cannot show the observed primary endpoint or its precision.

Even with a reported outcome count, the study’s single-group design would limit interpretation. It could describe outcomes in participants who received sunitinib, but would not directly show how those outcomes compare with another treatment or with no study treatment. The diagnosis-defined AA and GB cohorts do not supply randomized controls.

The serious and other adverse-event counts offer descriptive safety information, but do not by themselves establish causation. The registry also lists serious-event terms and percentages, while the basis for those percentages is not reported. The counts cannot be treated as a comparative estimate of excess risk.

Accordingly, the record supports conclusions about study structure, registered aims, endpoint definitions, and the posted safety summaries. It does not support a conclusion that sunitinib did or did not improve outcomes, nor does it establish the size or statistical certainty of a treatment effect. The absence of posted numerical efficacy results is an important limit, not evidence of either a favorable or unfavorable result.

14. Why This Trial Matters Statistically

This trial is statistically informative as an example of the distinction between a registered question and a reported result. The registry defines a fixed-time progression-free survival endpoint and names response criteria, but does not report the numerical primary outcome. A well-defined endpoint is necessary for interpretation, but it cannot answer the research question without the observed data and an account of their uncertainty.

The single-group design also illustrates the difference between describing outcomes and estimating comparative effects. Counts among treated participants may characterize what happened during a study, while a treatment comparison asks what would have happened to similar participants under an alternative. Without a randomized comparator, that counterfactual is not directly observed. The AA and GB cohorts are useful disease categories in the record, but do not create a control group.

For safety, the record shows counts of participants affected and lists several serious-event terms. Those data can communicate the presence of reported events, while their meaning depends on definitions, denominators, follow-up, and attribution. The registry does not provide all of those details for the term-specific percentages. Reading the counts carefully avoids turning descriptive summaries into causal or comparative claims.

Finally, the record demonstrates why completion status and enrollment are not substitutes for outcome reporting. The study is marked completed and reports enrollment of 30, yet numerical results for the primary and secondary outcomes are not posted. Statistical interpretation depends on the outcome estimates, uncertainty, analysis population, and methods—not only on the study design or its stated aims.

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.

A major limitation of the available record is that it does not report numerical results for the primary progression-free survival endpoint or the two secondary outcomes. No confidence intervals, p-values, or effect estimates are reported, so the size and precision of the study’s outcome findings cannot be assessed.

The trial has no concurrent comparator and is listed as single-group, with masking none and allocation NA. This prevents a controlled comparison within the study. The disease cohorts should not be treated as equivalent randomized arms: they represent AA and GB diagnoses and have different cohort sizes.

The record does not report the sample-size justification, detailed statistical analysis plan, multiplicity handling, interim analyses, missing-data methods, or sensitivity analyses. It identifies the primary outcome population as all participants but does not explain how missing or unevaluable assessments were handled. The endpoint description does not state detailed procedures for assessment timing, review, or death handling.

Safety interpretation is also limited by absent detail about the observation period, event attribution, and the denominator for the term-specific percentages. The serious-event and other-event summaries should not be conflated with the separately listed secondary outcome of related Grade 3 and greater adverse events, for which no result is reported. The posted counts are descriptive and cannot isolate treatment causation.

These limitations concern what the registry record reports; they do not establish what analyses investigators may have conducted outside the record.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: A Phase II Trial of Sutent (Sunitinib; SU011248) for Recurrent Anaplastic Astrocytoma and Glioblastoma — NCT00606008.
• Registry record last updated 2012-11-19; status last verified 2012-09.
• Results first posted 2012-10-31.
• 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

The record describes NCT00606008, a completed Phase II single-group study of sunitinib malate for recurrent anaplastic astrocytoma and glioblastoma. Enrollment was 30. Treatment was daily for 4 weeks at 50 mg, followed by a 2 week study-drug-free break. The primary endpoint was the number of participants with progression-free survival at 6 months using McDonald criteria, with all participants named as the outcome population.

Secondary outcomes were best overall response and participants with related Grade 3 and greater adverse events. Numerical results for the primary and secondary outcomes are not reported in the registry record. The safety record lists affected-participant counts and serious-event terms, but does not provide enough detail to support comparative or causal interpretation. No outcome analyses, statistical analysis plan, or sample-size justification are reported.