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 Rollover Study of Weekly Paclitaxel (BMS-181339) in Patients With Advanced or Recurrent Esophageal Cancer (NCT00971841), a na phase 2 study. The primary outcome is Number of Adverse Events (AEs) Per Participant.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00971841 |
| Phase | Phase 2 |
| Condition | Esophageal Cancer |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 1 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Bristol-Myers Squibb |
| Results posted | Yes |
2. Clinical Question
Population
The study enrolled a participant with advanced or recurrent esophageal cancer who had completed the previous Phase 2 study, CA139-540. Eligibility for continued treatment depended on the treating investigator’s assessment that paclitaxel should continue. The registry record reports one participant enrolled, so the observed experience represents one person rather than a broad sample of patients.
Intervention
The intervention was paclitaxel given by one-hour intravenous infusion on Days 1, 8, 15, 22, 29, and 36, followed by one week of rest. The record describes this as six weeks on and one week off, with a 49-day treatment course. The Day 1 dose was the same dose level as the last dose in the prior study: 100mg/m2, 80 mg/m2, or 60 mg/m2. Treatment was to continue until disease progression.
Comparator
There was no comparator group. The design is listed as single group, with allocation recorded as not applicable and no masking. The participant’s experience therefore cannot be contrasted with a concurrent control arm in this study.
Primary question
The primary outcome was the number of adverse events per participant, assessed weekly from Day 1 to 4 years. The study description emphasizes assessment of adverse-event severity and long-term safety. A secondary outcome was the number of participants with complete tumor response. The registry record does not report the observed primary or secondary outcome values, so it does not answer how many adverse events occurred or whether complete response was recorded.
3. Trial Design
This was a Phase 2, single-group rollover study of paclitaxel in esophageal cancer. Its stated purpose was to provide access to continued paclitaxel therapy for participants who had completed the earlier Phase 2 study CA139-540 and whose treating investigator considered ongoing treatment appropriate. The study also aimed to assess the severity of observed adverse reactions for long-term safety. This context matters: the study was not structured as a randomized comparison of paclitaxel with another treatment or with no treatment.
The registry lists enrollment of one participant and status as completed. The study began in 2008-03, and primary completion was recorded as 2012-04. These dates describe the study record and do not, by themselves, establish how long the participant received treatment or the completeness of follow-up for each outcome.
Paclitaxel was scheduled as a one-hour intravenous infusion on Days 1, 8, 15, 22, 29, and 36, followed by one week of rest. The record describes the cycle as six weeks on and one week off, with each course lasting 49 days. The Day 1 dose level matched the last dose received in CA139-540: 100mg/m2, 80 mg/m2, or 60 mg/m2. The listed treatment duration was until disease progression.
Allocation was not applicable, masking was none, and the model was single group. These features mean that the record describes an individual treatment experience rather than a blinded or controlled estimate of a treatment contrast. The registry record does not report a statistical analysis plan, a sample-size justification, or interim analyses. Completion status should not be mistaken for a report of the study’s outcomes: the outcome values and analysis results are not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Before assignment: To be enrolled in Study CA139-557, participants with advanced or recurrent esophageal cancer must have completed original Study CA139-540 (NCT 00344552) and investigator(s) deemed that continuing treatment with paclitaxel would benefit the participant.
Overall Study
| Stage | Paclitaxel |
|---|---|
| STARTED | 1 |
| COMPLETED | 1 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: Only one participant enrolled in the study so all results represent one participant.
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.
| Characteristic | Unit | Paclitaxel |
|---|---|---|
| Participants analysed | 1 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 1 |
| Age, Categorical: >=65 years | Participants | 0 |
| Age Continuous | years | 47 (SD NA) |
| Sex: Female, Male: Female | Participants | 1 |
| Sex: Female, Male: Male | Participants | 0 |
| Region of Enrollment: Japan | participants | 1 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Adverse Events (AEs) Per Participant, measured over Weekly Day 1 to 4 years.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | adverse events |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was the number of adverse events per participant, with a stated timeframe of weekly assessment from Day 1 to 4 years. An adverse event was defined as a new unfavorable symptom, sign, or disease, or worsening of a preexisting condition; the definition explicitly allowed that the event might not have a causal relationship with treatment. Severity was judged and graded according to National Cancer Institute Common Toxicity Criteria version 2.0.
A count endpoint records how many events are observed rather than measuring a single event or a time-to-event outcome. It can describe the burden of reported events, while severity grading can distinguish events of different clinical seriousness. These are general properties of count and severity outcomes, not evidence about what happened to this participant.
The registry record says that all results represent one participant because only one participant enrolled. It does not report the primary endpoint value, event-level details, or a severity distribution. Therefore, the endpoint definition is available, but its observed result cannot be characterized from the registry record. The secondary outcome, the number of participants with complete response to tumor, is also listed, but its result is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The record supports a narrow description of study structure and reported safety counts. It describes a completed, single-group Phase 2 rollover study with one participant enrolled. The participant had completed a prior study and was considered by the treating investigator to be an appropriate candidate for continued paclitaxel. There was no concurrent comparator, and the registry lists no masking. These design features make the record descriptive rather than a controlled estimate of comparative treatment effects.
The posted safety figures list one participant at risk for serious adverse events and zero participants affected by serious adverse events. For other adverse events, the figures list one participant at risk and one affected. These are participant-level counts in the registry’s safety summary; they do not give the total number of individual event episodes, their timing, their severity, or their relationship to paclitaxel. The deaths value is not reported in the registry record. The primary endpoint’s number of adverse events per participant is also not reported, so the safety summary cannot be used to reconstruct that endpoint.
With one participant, the observations describe that participant’s recorded experience only. They cannot establish how often similar events would occur in a wider patient population, nor can they provide a stable estimate of between-participant variation. A zero in the serious-event affected count is an observed registry entry for this study, not evidence that serious events would be absent in other patients or settings.
The registry record lists complete tumor response as a secondary outcome, but does not report its value. No tumor-response result, estimate of treatment effect, confidence interval, or hypothesis-test result is reported in the registry record. The record therefore does not permit an efficacy conclusion. Likewise, the treatment schedule and intended duration describe the protocol, not actual treatment exposure or a demonstrated clinical effect.
Any statistical interpretation should keep the distinction between an observed count and a population-level rate in view. A rate requires an appropriate exposure-time denominator and a clearly specified analysis; neither is reported for the primary endpoint. The record also does not report the analysis population beyond noting that all results represent one participant. Statistical precision and generalizability cannot be assessed from a single participant’s outcome summary, especially when the main endpoint value and its supporting details are not reported.
9. Statistical Methods Explained
The design determines which statistical questions the data can answer. A single-group study observes outcomes under one treatment strategy; without a comparison group, it does not estimate a difference between treatment strategies. In a randomized trial, allocation helps make groups comparable on average, while masking can reduce some forms of bias in assessment. This study lists allocation as not applicable and masking as none, and it is described as single group. These are design details, not evidence that the study was intended to test a comparative effect.
What does a count endpoint capture?
A count endpoint records the number of events in a defined observation period. Count data are nonnegative and may be unevenly distributed: many people can have few events while a smaller number have more. As a general statistical matter, a count model may need to account for over-dispersion, meaning that variation is greater than a simple model expects. If observation time differs between participants, rates and exposure time may also matter. Those considerations require event counts, follow-up or exposure information, and a specified analysis. The registry record reports one participant and a weekly-to-4-years timeframe, but does not report the primary count result or a model used to analyze it.
Common count-data models include Poisson and negative-binomial approaches. This is general methodological context, not a description of the analysis used in this study: the statistical model is not reported in the registry record. A model’s assumptions should not be inferred from the endpoint being a count. In particular, the record does not identify whether the outcome was modeled as a count, converted to a rate, or described without inferential modeling.
Why does over-dispersion matter?
In general, a model that understates variability can produce confidence intervals that are too narrow and tests that appear more decisive than the data justify. A confidence interval communicates uncertainty around an estimate under the chosen statistical model and its assumptions. It does not correct a weak design or create information absent from the data. For this study, the registry record does not report an estimate, confidence interval, or model-based analysis. With one participant, between-participant variability cannot be estimated from the enrolled group in a meaningful population-level way.
How should severity grading be understood?
The endpoint description says adverse-event severity was judged and graded using National Cancer Institute Common Toxicity Criteria version 2.0. Severity grading is a classification of the reported event’s seriousness under a defined framework; it is distinct from deciding whether treatment caused the event. The registry’s adverse-event definition explicitly includes events that may not have a causal relationship with treatment. The record does not report individual event terms or grades, so the safety counts alone cannot show the severity profile.
What can a confidence interval or test add?
In general, a confidence interval can show the range of estimates compatible with the observed data under a statistical model. A hypothesis test evaluates data against a specified null hypothesis and assumptions. Neither can be interpreted without an estimate, a defined comparison or target, and a stated analytic method. The registry record lists no analyses, and it does not report test statistics, p-values, or intervals. It is therefore not possible to describe inferential precision or statistical significance for the primary endpoint.
What do planning calculations mean?
Sample-size calculations are planning tools for a future study, not observed outcomes and not evidence of the probability that this completed study detected an effect. The planning assumptions described in the record refer to a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and effects expressed as fractions of an observed effect. The record does not report the trial’s own sample-size justification. Any planning illustration based on an observed effect should be read as an assumption-dependent projection for a proposed design, not as observed power or as a result of this one-participant, single-group study. A two-arm planning setup also does not change the actual design of the rollover study.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary adverse-event count outcome and a secondary outcome of the number of participants with complete tumor response. Considering more than one outcome can raise a multiplicity issue: when several hypotheses are tested, the chance of at least one apparently unusual result can increase if each is assessed separately. Statistical approaches can address this, for example by defining one primary test in advance or adjusting for multiple comparisons. This is general context only. The registry record does not report a multiplicity procedure, a hierarchy of statistical tests, or results for either outcome.
The registry record lists no analyses. It does not report whether an analysis plan was finalized before outcome data were reviewed, whether any interim analyses took place, or how any testing across outcomes was handled. Those details should not be inferred from the Phase 2 designation or from the listed outcome order.
Missing-data methods are also not reported in the registry record. The record does not describe how incomplete follow-up, missed weekly assessments, discontinuation, or unavailable outcome information would be handled. The listed timeframe runs from weekly assessment on Day 1 to 4 years, but this does not establish that observations were available for the full timeframe. The deaths value is not reported in the registry record, and the primary endpoint value is not reported.
The analysis population is described only to the extent that the primary outcome notes one participant enrolled and says all results represent that participant. The record does not report a named analysis population, such as an intention-to-treat or per-protocol population, or rules for including participants in an analysis. With one enrolled participant, missingness or exclusion could be especially consequential, but the record does not provide enough detail to determine whether that occurred.
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 |
|---|---|---|---|
| Paclitaxel | 0 | 1 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 1% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Paclitaxel | 1 of 1 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Paclitaxel |
|---|---|---|
| neutrophil count decrease | Investigations | 1 of 1 |
| alopecia | Skin and subcutaneous tissue disorders | 1 of 1 |
| back pain | Musculoskeletal and connective tissue disorders | 1 of 1 |
| blood pressure increased | Investigations | 1 of 1 |
| chills | General disorders | 1 of 1 |
| contusion | Injury, poisoning and procedural complications | 1 of 1 |
| cough | Respiratory, thoracic and mediastinal disorders | 1 of 1 |
| cystitis | Infections and infestations | 1 of 1 |
| decreased appetite | Metabolism and nutrition disorders | 1 of 1 |
| dizziness | Nervous system disorders | 1 of 1 |
The registry safety summary lists one participant at risk for serious adverse events and zero affected by serious adverse events. It also lists one participant at risk for other adverse events and one affected. These are participant counts, not a complete description of the number, timing, or severity of individual events. The primary endpoint is the number of adverse events per participant, but that endpoint value is not reported in the registry record.
The adverse-event definition includes new unfavorable symptoms, signs, or diseases, as well as worsening of a preexisting condition, and allows that an event may not be causally related to treatment. Accordingly, a recorded adverse event should not automatically be interpreted as caused by paclitaxel. The record says severity was graded using National Cancer Institute Common Toxicity Criteria version 2.0, but does not give the event-level grades or terms in the information reported.
The deaths entry is not reported in the registry record. It should not be read as a reported zero. The serious-event count of zero is the registry’s reported affected-participant figure for this study; with one participant, it is a description of the recorded study experience, not a precise estimate of risk in a broader population.
12. What the Result Does, and Does Not, Mean
The record documents a rollover study intended to allow continued paclitaxel treatment for a participant who had completed a prior Phase 2 study and was assessed by the treating investigator as appropriate for continued therapy. It also documents a long-term safety objective, a weekly adverse-event assessment timeframe, and an outcome definition based on adverse-event counts and severity grading. The posted safety summary records no participant affected by a serious adverse event and one affected by other adverse events, among one participant at risk in each category.
Those observations do not establish the frequency of adverse events in a larger population. A single participant’s experience cannot characterize the range of outcomes across patients, and the summary lacks event-level details needed to describe the number, timing, type, or severity of events. The deaths value is not reported in the registry record. The primary endpoint value and the complete-response result are also not reported.
The study does not include a concurrent comparator. As a result, the record cannot isolate a treatment effect by contrasting outcomes under paclitaxel with outcomes under another strategy. The fact that treatment was intended to continue until disease progression is a protocol description, not evidence about actual treatment duration or disease course.
No efficacy conclusion follows from the study title, treatment schedule, or completed status. The secondary response outcome is listed without its result, and no effect estimate, confidence interval, or inferential analysis is reported. Nor does the serious adverse-event count establish that serious events would not occur in other participants. The most defensible interpretation is limited to the registry’s design and its small set of posted safety counts, while recognizing that key outcome and analysis details are not reported.
13. Why This Trial Matters Statistically
This study is statistically instructive because its rollover purpose and single-participant enrollment place clear limits on the questions its record can address. Rollover studies can describe continued treatment experience in a selected group, especially when treatment continuation depends on clinical judgment after an earlier study. That selection context differs from a design intended to estimate outcomes in an unselected population. Here, the record explicitly describes eligibility through completion of CA139-540 and an investigator’s assessment that paclitaxel should continue.
The distinction between describing an individual outcome and estimating a population pattern is central. The registry lists one participant, while the primary endpoint is a participant-level event count intended to inform safety. A count from one person can document that person’s reported experience, but it cannot provide a reliable estimate of variation between people. The posted serious and other adverse-event participant counts are similarly descriptive and should not be treated as population rates.
The record also illustrates why endpoint definitions and results must be read separately. It defines adverse events broadly, including events that may not be caused by treatment, and specifies a severity-grading framework. Yet the primary count, event terms, and grades are not reported in the registry record. A clear definition improves interpretability, but it does not substitute for outcome data.
Finally, a completed study is not necessarily a fully reported study. The registry identifies the study as completed and lists its outcomes, but does not report outcome values or analyses. For statistical readers, that distinction prevents a protocol description from being mistaken for evidence of efficacy or a comprehensive safety estimate. It also highlights the importance of outcome reporting, analysis methods, and follow-up details when interpreting even a small descriptive study.
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 most direct limitation is enrollment of one participant. The resulting safety summary is an account of one participant’s recorded experience and cannot support reliable estimates of population event rates or between-participant variability. The absence of a comparator further limits interpretation: outcomes cannot be contrasted with a concurrent alternative, and the design does not estimate a comparative treatment effect.
The registry record does not report the primary adverse-event count, the complete-response outcome, event terms, grades, or the deaths value. It therefore provides limited detail for assessing the nature and timing of safety observations, and it does not permit interpretation of the listed tumor-response outcome. The stated weekly-to-4-years timeframe does not demonstrate how much observation time was actually completed.
Allocation was not applicable and masking was none. The record does not report a statistical analysis plan, a sample-size justification, interim analyses, multiplicity handling, missing-data methods, or a named analysis population. The basis for any analysis decisions therefore cannot be assessed from the registry record. The record also does not report whether all planned assessments were completed or how discontinuation and follow-up were managed.
The rollover eligibility context may limit how well the experience applies to people who did not complete the previous study or whose investigator did not recommend continued therapy. The actual dose level for the enrolled participant is not specified in the record, which lists possible dose levels. Together, the single-group design, enrollment of one participant, and missing outcome and analysis details make broad conclusions inappropriate.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Rollover Study of Weekly Paclitaxel (BMS-181339) in Patients With Advanced or Recurrent Esophageal Cancer — NCT00971841.
- Registry record last updated 2013-07-26; status last verified 2013-07.
- Results first posted 2013-07-19.
- 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 describes a completed Phase 2, single-group rollover study of weekly intravenous paclitaxel in advanced or recurrent esophageal cancer. Its purpose was to allow continued treatment after completion of the earlier study CA139-540 when the treating investigator considered continued therapy appropriate, and to assess long-term safety. Enrollment was one participant. The record lists no comparator and no masking.
The primary outcome was the number of adverse events per participant, assessed weekly from Day 1 to 4 years, with severity graded using National Cancer Institute Common Toxicity Criteria version 2.0. Complete tumor response was listed as a secondary outcome. The posted safety summary records zero participants affected by serious adverse events and one affected by other adverse events, with one participant at risk in each category. The deaths value, primary endpoint result, and secondary outcome result are not reported in the registry record. No analyses are listed.