A Phase II Evaluation of Dasatinib (Sprycel®, NSC #732517) in the Treatment of Persistent or Recurrent Epithelial Ovarian, Fallopian Tube, or Primary Peritoneal Carcinoma: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Phase II Evaluation of Dasatinib (Sprycel®, NSC #732517) in the Treatment of Persistent or Recurrent Epithelial Ovarian, Fallopian Tube, or Primary Peritoneal Carcinoma (NCT00671788), a na phase 2 study. The primary outcome is Progression-free Survival at 6 Months.

2. Clinical Question

3. Trial Design

This was a phase II, single-group trial sponsored by the Gynecologic Oncology Group. The registry lists enrollment as 35 and describes treatment with dasatinib for persistent or recurrent epithelial ovarian, fallopian tube, or primary peritoneal carcinoma. Allocation is listed as not applicable, and masking as none. The design therefore does not include a randomized treatment allocation or a blinded comparison group.

Patients received oral dasatinib once daily on days 1-28. Courses repeated every 28 days in the absence of disease progression or unacceptable toxicity. Laboratory biomarker analysis was also listed as an intervention. The registry identifies frequency and severity of adverse events assessed by CTCAE v3.0, progression-free survival, and overall survival as secondary outcomes. It lists five outcome measures, but does not report the analyses for these outcomes.

The registry lists the study as starting in 2008-06, reaching primary completion in 2010-12, and having completed status. These dates and status describe the administrative record, not the availability of a numerical primary outcome. The progression assessment schedule, eligibility details, handling of treatment discontinuation, and statistical analysis plan are not reported in the registry record. With no concurrent control group, outcome observations characterize the treated group and do not by themselves estimate a 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

Reasons for not completing this period:

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: Eligible and treated participants

6. Primary Endpoint

The registry lists the primary outcome as Progression-free Survival at 6 Months, measured over Scans to assess progression were done every other cycle for the first 6 months; every three months thereafter; and any time if clinically indicated based on symptoms or physical signs suggestive of progressive disease..

The primary endpoint was progression-free survival at 6 months, reported as a percentage of participants. It is intended to describe the share of the study group meeting the protocol’s progression-free definition at a specified follow-up point. Such an endpoint can summarize disease status over time while incorporating a defined assessment schedule, but the registry record does not give the observed percentage or the associated 90% confidence interval.

Progression was defined using RECIST v1.0: a 20% increase in the sum of the longest diameter of target lesions, using the smallest sum recorded since study entry as reference; unequivocal progression of existing non-target lesions; or appearance of one or more new lesions. CT or MRI was used to follow measurable disease. Scans were scheduled every other cycle for the first 6 months, every three months thereafter, and at any time when symptoms or physical signs suggested progression. The description also mentions rising serum tumor marker levels as a reason for clinically indicated assessment. Responses were to be confirmed by repeat imaging 4 weeks after documentation.

The endpoint’s clinical interpretation depends on these definitions and on the timing and completeness of assessments. The registry record does not state how missing scans or participants without evaluable follow-up were handled in calculating the endpoint.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a single-group phase II study and identifies a binary percentage endpoint: progression-free survival at 6 months. Its stated dispersion measure is a 90% confidence interval. The numerical estimate and interval are not reported in the registry record. The following statistical explanations are general; they clarify how such methods are ordinarily interpreted without adding an unreported analysis to this trial.

What does a confidence interval express?

A confidence interval conveys uncertainty around an estimate. For a percentage, it indicates a range of values reasonably compatible with the data under the interval’s statistical assumptions. A narrower interval generally indicates greater precision, while a wider interval indicates less precision. It is not a guarantee that the true value lies within the displayed range, nor does it measure the probability that a particular treatment effect is true. The registry’s stated 90% confidence level does not reveal the interval’s width; that would require the estimate and interval limits, which are not reported in the registry record.

The confidence interval also does not address all sources of uncertainty. It describes sampling uncertainty under the analysis used, but cannot remove uncertainty from outcome definitions, incomplete follow-up, measurement practices, or design limitations. In a single-group study, an interval around the observed percentage would describe that group’s endpoint estimate, not a randomized treatment contrast.

How does the endpoint become a percentage?

In general, a binary percentage summarizes participants classified into one of two outcome categories under a specified rule and time point. Here, the endpoint description identifies progression criteria and a 6-month horizon. To interpret an estimate, readers would also need to know the analysis denominator, how participants without a documented assessment were classified, and how time-to-progression information was handled. These details are not reported in the registry record. The stated enrollment alone does not establish the denominator used for the primary endpoint.

The registry’s progression criteria draw on lesion measurements and the appearance of new lesions. Imaging is scheduled over follow-up, with additional assessment when clinically indicated. A measured endpoint can depend on when scans occur: progression is observed at an assessment, while the biological change may have occurred between assessments. This is a general feature of outcomes assessed at intervals. The record gives the planned assessment timing but does not report scan completion or deviations.

What does the single-group design allow?

In a randomized comparison, treatment groups can support estimation of a difference between assigned strategies, subject to the trial’s assumptions and conduct. A single-group study has no internal randomized contrast. Its endpoint can describe outcomes in participants who received the study treatment, but it cannot isolate treatment effects from the course of disease or other influences using a concurrent control. Comparisons with experience outside the trial would require appropriate external data and careful accounting for differences; such a comparison is not reported in the registry record.

Masking is listed as none. In general, lack of masking can affect outcomes that involve judgment or reporting, although imaging-based progression criteria provide explicit rules for classification. The registry does not report who reviewed scans, whether review was independent, or whether assessment procedures were otherwise standardized beyond the stated schedule and criteria. No inference about those procedures should be added to the record.

How should planning calculations be read?

Sample-size calculations are planning illustrations, not observed evidence about the trial’s result. The registry’s stated assumptions for the illustrations include a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect specified as a fraction of the observed effect. For time-to-event calculations, the stated quantity is a total number of events; for other calculations, it is participants per arm. These assumptions do not describe this single-group trial’s actual allocation, and the illustrations should not be read as observed power. The registry record does not report the trial’s own sample-size justification or statistical plan. No planning count or detectable effect should be inferred from the assumption statement alone.

In general, power calculations describe the chance of detecting a specified effect under an assumed model, if the assumptions hold. They do not measure whether an observed finding is reliable, and retrospective calculations based on an observed effect can be misleading because the observed estimate is itself uncertain. Planning for a fraction of an observed effect illustrates sensitivity to the assumed effect size; it does not establish that the study was designed to detect that particular effect.

What is over-dispersion, and is it reported?

Over-dispersion is a general statistical issue in which observed variability exceeds what a model assumes. When that occurs, standard errors based on the simpler model may be too small, making intervals too narrow and tests too optimistic. It can arise in some count or clustered-data settings, depending on the data structure and model. The registry record does not report an over-dispersion assessment or a model for the primary endpoint. Since the primary result and analysis are not reported, it is not possible to determine whether this issue applied to the trial’s analysis.

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("Dasatinib")
n      <- c(34)
events <- c(7)
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  Dasatinib  34  7  20.6  8.7  37.9  10.3  36.8  10.4  36.9

11. Multiplicity, Missing Data and Analysis Populations

The registry lists progression-free survival at 6 months as the primary endpoint and identifies frequency and severity of adverse events, progression-free survival, and overall survival as secondary outcomes. It also lists laboratory biomarker analysis. Multiple outcomes or analyses can raise multiplicity concerns: when many hypotheses are tested, the chance of at least one apparently notable result can increase. Whether adjustment is needed depends on the objectives, analysis plan, and interpretation intended for each outcome. A multiplicity strategy is not reported in the registry record.

The record lists five outcome measures and zero analyses. That information does not supply numerical outcome estimates, hypothesis tests, or an account of which outcomes were analyzed. The registry record does not report a prespecified testing hierarchy, adjustment procedure, interim analyses, or a statistical analysis plan. Their presence or absence beyond what is explicitly recorded cannot be inferred.

Missing-data handling is also not reported. The record does not specify how participants without an assessment at 6 months were treated, how incomplete imaging follow-up affected endpoint classification, or how treatment discontinuation and censoring were handled. These decisions matter because the endpoint depends on follow-up and imaging assessments. The registry enrollment figure does not establish the analysis population or denominator for the primary outcome.

The adverse-event entries use a safety population at risk of 34 in the dasatinib group, while the registry enrollment is 35. The reason for this difference is not reported in the registry record, and no reconciliation should be assumed. The registry does not describe a full analysis-population framework, such as whether an intention-to-treat or evaluable-participant population was used for efficacy outcomes. These reporting gaps limit assessment of how complete, comparable, or prespecified the analyses were.

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 0% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: obstruction, gi - small bowel nos (14.7%), pain: abdominal pain nos (8.8%), rhinitis (2.9%), cardiac general - other (2.9%), weight loss (2.9%).

The registry lists serious adverse events for the dasatinib group with 34 participants at risk and 18 affected. It lists other adverse events with 34 at risk and 33 affected. These are separate entries and should be read as counts of participants recorded as affected in the respective categories, not as counts of individual event episodes. A participant may experience more than one type of event; the record does not describe overlap among terms.

The listed serious-event terms include obstruction, GI - small bowel NOS at 14.7%, pain: abdominal pain NOS at 8.8%, and rhinitis, cardiac general - other, weight loss, and distention at 2.9% each. These percentages describe the registry’s listed terms; the record does not provide further detail on event timing, duration, severity grading for each term, or attribution. The outcome description identifies adverse events assessed by CTCAE v3.0, but that does not establish that every listed event was caused by the study drug.

The deaths entry is null, so deaths are not reported in that registry entry. This is not evidence that no deaths occurred. The safety denominator is also not the same as the enrollment figure, and the reason is not reported. These safety figures are descriptive and should not be treated as a comparison with another treatment group, since this was a single-group study.

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

The registry record establishes that this was a phase II, single-group evaluation of dasatinib in persistent or recurrent ovarian, fallopian tube, or primary peritoneal carcinoma. It specifies the treatment schedule, the primary endpoint, and the rules used to define progression. It also includes adverse-event counts for the dasatinib group. Those details help readers understand what the study set out to assess and how some outcomes were classified.

The record does not report the observed six-month progression-free survival percentage or its 90% confidence interval. It therefore does not establish the size or precision of the primary endpoint. The completed status and primary completion date do not supply a missing outcome estimate. Nor does the record report the secondary outcome results or the biomarker findings.

Even with a numerical endpoint estimate, the single-group design would describe outcomes among treated participants rather than provide a randomized estimate of the difference attributable to treatment. The absence of a concurrent comparator limits causal interpretation. It also means that a comparison with other treatments cannot be made from this record alone.

The listed safety counts can be used to describe how many participants were recorded as affected in the serious and other adverse-event categories. The event terms and percentages provide additional descriptive detail. They do not, without an appropriate comparison or further clinical context, establish that the treatment caused an event or quantify risk relative to another option. The null deaths entry means the record does not report deaths in that field; it should not be read as a claim that none occurred.

Overall, the registry record supports a description of trial design, endpoint definitions, treatment exposure, and selected safety information. It does not provide enough outcome reporting to judge the primary endpoint’s result or its precision, and it does not support comparative efficacy conclusions.

14. Why This Trial Matters Statistically

This trial illustrates an important distinction between an endpoint definition and an endpoint result. The registry specifies progression-free survival at 6 months, the imaging schedule, and RECIST v1.0 criteria. Those details define what investigators intended to measure. Without the observed percentage and its 90% confidence interval, however, readers cannot evaluate the estimate or its precision. Clear endpoint descriptions are useful, but they do not replace outcome reporting.

The single-group design is also statistically important. It can provide a description of outcomes in a treated cohort, but it lacks an internal randomized comparator for estimating a treatment contrast. This limits what can be concluded even when outcomes are measured carefully. The design should be kept in view whenever interpreting a phase II result or considering how it might compare with other evidence.

The registry also highlights the difference between enrollment and a particular outcome’s analysis population. It reports enrollment of 35 and safety denominators of 34. The reason for the difference is not reported, and the primary endpoint denominator is not available. Transparent accounting of who was included in each analysis helps readers assess missing follow-up and interpret outcome percentages.

Finally, the safety entries show why counts, terms, and denominators need to be read together. The registry reports serious and other adverse-event counts in the treated group, along with selected term percentages, but those descriptions are not a controlled comparison and do not establish causation. Taken together, the record offers useful methodological context while leaving central efficacy and analysis details unreported.

15. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The principal limitation for interpretation is that the registry record does not report the primary endpoint result. Although progression-free survival at 6 months and a 90% confidence interval are specified, neither the estimate nor interval limits are present. The record also does not report secondary outcome results, despite listing progression-free survival, overall survival, and adverse events among the outcomes.

The study was single-group and unmasked, with allocation listed as not applicable. There is no concurrent randomized comparator in the registry design, so a causal treatment contrast is unavailable from the trial structure. The record does not describe external controls or comparative analyses. The lack of masking may be relevant to outcome assessment or reporting in general, but scan-review procedures and independent assessment are not reported.

Important analysis details are absent. The registry record does not report the statistical analysis plan, sample-size justification, primary endpoint analysis population, missing-data rules, censoring approach, or handling of participants without a 6-month scan. It describes an imaging schedule but does not report assessment completion or deviations. The listed enrollment and safety denominators do not resolve the endpoint’s denominator or explain the difference between those entries.

Safety reporting is also limited in the record: deaths are null in the adverse-event entry, and further event-level detail and attribution are not reported. The listed adverse-event figures remain descriptive and cannot be compared with a control group in this design. These limitations mean the record can describe the trial’s stated methods and selected safety counts, but cannot support a full evaluation of efficacy, precision, or comparative safety.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: A Phase II Evaluation of Dasatinib (Sprycel®, NSC #732517) in the Treatment of Persistent or Recurrent Epithelial Ovarian, Fallopian Tube, or Primary Peritoneal Carcinoma — NCT00671788.
• Registry record last updated 2016-04-15; status last verified 2016-03.
• Results first posted 2014-07-18.
• 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

NCT00671788 is a completed phase II, single-group study sponsored by the Gynecologic Oncology Group. It evaluated oral dasatinib in persistent or recurrent epithelial ovarian, fallopian tube, or primary peritoneal carcinoma. The registry lists enrollment as 35 and a primary endpoint of progression-free survival at 6 months, expressed as a percentage with a 90% confidence interval.

The record describes RECIST v1.0 progression criteria and an imaging schedule, but does not report the primary endpoint estimate or interval. It also does not report the listed secondary outcome results or a statistical analysis plan. Safety entries list 18 of 34 participants affected by serious adverse events and 33 of 34 affected by other adverse events; deaths are null in the record. The design has no concurrent comparator, so the registry supports descriptive interpretation rather than a randomized treatment comparison.