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 Trastuzumab (Herceptin), Bevacizumab, and Docetaxel (Taxotere) Trial in Stage IV Metastatic Breast Cancer (MBC) Patients (NCT00428922), a na phase 2 study. The primary outcome is Progression-free Survival (PFS) and to Evaluate Safety of the Trastuzumab, Bevacizumab and Docetaxel Regimen..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00428922 |
| Phase | Phase 2 |
| Condition | Breast Cancer |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 26 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Bhuvaneswari Ramaswamy |
| Results posted | Yes |
2. Clinical Question
Population
People with stage IV metastatic breast cancer are the population named in the trial title. The registry lists breast cancer as the condition and records enrollment of 26 participants. Eligibility details, including any biomarker requirements, are not reported in the registry record.
Intervention
The single study group received trastuzumab, bevacizumab, and docetaxel. The arm description lists doses of 6mg/kg, 15mg/kg, and 75 mg/M², respectively. Further details about how treatment was administered are not reported in the registry record.
Comparator
There was no separate comparator group: the model is listed as single group and allocation as NA. The registry does not describe a randomized or like-for-like control comparison.
Primary question
The stated primary objectives were to determine progression-free survival (PFS) and evaluate the safety of the three-drug regimen. The primary outcome is described as median PFS, in months, with a 95% confidence interval and a timeframe of up to 3 years. The actual median and confidence interval are not reported in the registry record.
In practical terms, this study was intended to describe how long participants remained alive without recorded disease progression, while also monitoring safety. PFS is a time-to-event outcome: in general, it concerns the time until progression or death. The registry record does not give the trial’s operational definition of progression, the assessment schedule, or details of how events were confirmed. Those omissions matter when interpreting a time-to-event endpoint, because the event definition and follow-up procedures determine what is counted and when.
The secondary outcomes listed are changes in circulating tumor cells (CTCs) and circulating endothelial cells (CECs) as predictors of PFS and clinical benefit, and overall clinical benefit rate (CR+PR+SD). Numerical findings for these outcomes are not reported in the registry record. The posted information therefore frames the clinical question and intended outcomes, but does not establish the observed PFS or describe the magnitude of clinical benefit.
3. Trial Design
This is a phase II study recorded as completed, with a single-group model and no masking. Enrollment is listed as 26. The registry record describes one treatment group receiving trastuzumab, bevacizumab, and docetaxel; it does not describe a concurrent control group or a randomized allocation. The design can therefore describe outcomes among participants treated in this study, but it cannot make a direct randomized comparison with another treatment.
The registry’s primary outcome description says the study used a single-stage phase II design rather than the more usual two-stage design. Its stated rationale was that waiting to assess PFS among participants in a first stage was impractical. The design description identifies a PFS of 50% at twelve months, corresponding in the record to a median PFS of 12 months, or less as uninteresting, and a PFS of 70% at twelve months, corresponding to a median PFS of twenty months, as worthy of pursuing the regimen in future trials. It gives p0=0.50, p1=0.70, α=0.10, and β= 0.10, and states a total sample size of 39 patients, with 24 or higher progression-free at 12 months.
Those statements describe the planned design, not the observed outcome. Enrollment is listed as 26, and the primary endpoint result is not reported in the registry record. The record does not explain the difference between the planned total sample size of 39 and the enrollment of 26. It also does not report whether the stated decision threshold was reached.
The listed timeframe for the primary outcome is up to 3 years. Start and primary completion dates appear in the registry record, but the record does not provide details about participant-level follow-up, treatment duration, or the timing and frequency of outcome assessments. The study status is completed; completion status alone does not provide an estimate of PFS or a safety conclusion.
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 | Trastuzumab, Bevacizumab, and Docetaxel |
|---|---|
| STARTED | 26 |
| COMPLETED | 26 |
| NOT COMPLETED | 0 |
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 | Trastuzumab, Bevacizumab, and Docetaxel |
|---|---|---|
| Participants analysed | 26 | |
| Age, Continuous | years | 54 (38 to 73) |
| Sex: Female, Male: Female | Participants | 26 |
| Sex: Female, Male: Male | Participants | 0 |
| Region of Enrollment: United States | patients | 26 |
6. Primary Endpoint
The registry lists the primary outcome as Progression-free Survival (PFS) and to Evaluate Safety of the Trastuzumab, Bevacizumab and Docetaxel Regimen., measured over up to 3 years.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | 95% Confidence Interval |
| Unit | months |
| Endpoint classification | Time-to-Event Analysis |
The primary outcome is described as progression-free survival (PFS), with the parameter reported as a median in months and dispersion described by a 95% confidence interval. In general, PFS is a time-to-event measure concerning the time until disease progression or death. The exact event definition used in this trial, including how progression was assessed and whether particular events were handled in a special way, is not reported in the registry record.
A median summarizes the time-to-event distribution by identifying the point at which the estimated proportion of participants who remain event-free reaches one half. It is often used when follow-up times differ or when not everyone has experienced the event by the end of observation. A confidence interval conveys uncertainty around an estimate; it is not a guarantee that the true value lies within that interval. The registry lists a 95% confidence interval as the planned dispersion measure, but does not report the median or its interval.
PFS is relevant to the stated study objective because it captures time without documented progression or death, rather than only whether an event occurred at a single fixed visit. The registry’s design description also discusses PFS at twelve months as a decision point. The actual PFS estimate, the number of events, and the number of participants still under observation at relevant times are not reported in the registry record. The second primary objective was safety, but a detailed safety analysis plan is not reported there.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a completed phase II study of a three-drug regimen and states that its primary objectives were PFS and safety. It lists enrollment of 26 and describes one treatment group. However, it does not report the observed median PFS, its 95% confidence interval, a PFS estimate at twelve months, or a hazard ratio. Consequently, the posted record does not support a numerical conclusion about the duration of PFS in this group or the precision of such an estimate.
The design description supplies planning benchmarks: PFS of 50% at twelve months or less was designated uninteresting, while PFS of 70% at twelve months was described as worthy of pursuing the regimen in future trials. It also states the planned single-stage design parameters and a target total sample size of 39. These are prospective design statements, not findings. They should not be read as evidence that either benchmark was achieved. The record does not say whether the decision rule was met, and enrollment is listed as 26 rather than the planned total of 39.
Because this is a single-group study without a comparator, any reported outcome would describe participants in this study rather than a randomized contrast between treatments. In general, an uncontrolled study cannot separate the observed course from other explanations as well as a randomized comparison can. This is a design limitation, not a reason to dismiss descriptive results; it does define the scope of what such results can show. Here, the absence of a reported primary endpoint result makes even a descriptive numerical assessment unavailable from the registry record.
The safety fields list 26 participants at risk for serious adverse events and 0 affected, and 26 at risk for other adverse events and 26 affected. These counts should be read as the registry’s posted group-level figures, not as a complete account of event types, severity, timing, or attribution. The record does not provide serious adverse event terms, and the death count is not reported. The other adverse event count indicates that all 26 listed as at risk were listed as affected in that category, but does not explain which events occurred.
The listed secondary outcomes concern CTCs, CECs, and overall clinical benefit rate. Their numerical results are not reported in the registry record. The registry lists four outcome measures and zero analyses. It does not provide an analysis population, a missing-data approach, or details of statistical methods used to produce any results. Therefore, interpretation should stay close to what is explicitly recorded: the study’s aims and design are described, but key efficacy results and much of the supporting analysis are not.
9. Statistical Methods Explained
The registry describes a phase II, single-group study with a time-to-event primary outcome. The following explains the statistical ideas behind the stated design in general terms and distinguishes planned values from observed findings. The primary endpoint result itself is not reported in the registry record.
What does a median PFS summarize?
For a time-to-event outcome, the median is a summary of the distribution of event times. It is not the average time for every participant, and it does not mean that each participant experiences the event at that time. Some participants may have an event earlier, while others may remain event-free longer or have incomplete follow-up. Time-to-event methods are designed to account for differing follow-up and censoring, where a participant’s event time is not observed during the available observation period.
The registry names median PFS in months and a 95% confidence interval. In general, the confidence interval expresses uncertainty in an estimate. A narrower interval indicates greater precision than a wider interval, while the estimate alone does not show its precision. No median or interval is posted here, so the precision of the primary PFS estimate cannot be assessed from the registry record.
What does the single-stage design describe?
The registry says the study used a single-stage phase II design because it considered waiting for first-stage PFS assessment impractical. Its description sets out two planning benchmarks: p0=0.50 and p1=0.70, stated in terms of PFS at twelve months. In general, p0 and p1 represent design reference values for a less promising and a more promising outcome, respectively. They are not observed rates. The registry also lists α=0.10 and β= 0.10. In general, alpha is a design tolerance for a false-positive decision under the null reference, while beta is a design tolerance for failing to identify the alternative under the design assumptions. These quantities characterize the planned decision procedure; they do not report the uncertainty of an observed trial result.
The record states that the design leads to a total sample size of 39 patients and that 24 or higher should be progression-free at 12 months. Those are design specifications. The enrollment field lists 26. The record does not explain why enrollment differs from the planned total, whether the decision rule was applied, or what number was progression-free at twelve months. The planned threshold must therefore not be treated as an observed count.
Why does a single group limit comparisons?
A single-group study has no concurrent control arm in the registry record. In general, this means outcomes can be described within the treated group, but a treatment contrast cannot be estimated from a randomized comparison in the study. Comparisons with historical expectations can be part of a phase II design, but the registry’s planned benchmarks are not a substitute for an observed control group. Differences between this group and a historical reference may reflect patient selection, follow-up, outcome assessment, or other factors, as well as treatment.
Allocation is listed as NA, masking as none, and the model as single group. These entries are consistent with the absence of a randomized comparator. The registry does not report additional procedures intended to reduce bias in assessment or analysis. In general, lack of masking can matter when outcomes depend on judgment; the extent of that concern depends on the endpoint and assessment procedures, which are not described in detail.
What can a confidence interval and hazard ratio contribute?
A confidence interval is useful alongside an estimate because it shows the range of values compatible with the analysis under its assumptions. For PFS, it helps communicate how precisely the median is estimated. It does not account automatically for every source of bias or uncertainty, such as differences in outcome assessment or missing follow-up.
A hazard ratio can summarize the relative event rate over time in a specified comparison. In general, its interpretation depends on the comparison groups, model assumptions, and the proportional-hazards framework when that framework is used. The registry record does not report a hazard ratio or a comparator group for this trial. The primary outcome is described as a median, and the posted record does not give enough information to assess a hazard-ratio analysis.
How should sample-size illustrations be read?
Any sample-size illustrations displayed with this page are planning calculations, not evidence of observed power. In general, a planning calculation asks how many participants or events might be needed under specified assumptions to detect a chosen effect with a chosen significance level. The figures depend on the assumptions and are not an analysis of what the completed study actually found. The registry’s design description gives its own single-stage planning target; that target should be distinguished from any later illustration.
The registry record does not report the observed effect needed to interpret a sample-size illustration, a sponsor-reported hazard ratio, or an analysis using a comparator. It also does not report the statistical analysis methods used for the posted endpoint results. Without those details, planning illustrations cannot establish that the study was adequately sized for a particular observed result, and they cannot replace a reported estimate with its uncertainty.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists four outcome measures and zero analyses. It identifies PFS and safety as the primary objectives, with secondary outcomes involving CTC changes, CEC changes, and overall clinical benefit rate (CR+PR+SD). The registry record does not report how many statistical tests were planned or conducted for these outcomes, whether any outcome was designated as primary for a particular analysis, or how multiplicity was handled.
In general, examining several outcomes or several analyses can increase the chance of a chance finding if each is interpreted without an adjustment or a prespecified hierarchy. That general concern does not establish that an adjustment was required or omitted in this trial: the statistical plan is not reported in the registry record. The listed count of zero analyses does not explain whether analyses were not entered, were not performed, or were reported elsewhere.
Missing-data procedures and analysis populations are not reported in the registry record. It does not state whether the primary analysis included all enrolled participants, only participants who began treatment, or another defined group. It also does not describe how incomplete follow-up, censored observations, or missing biomarker measurements were handled. These details are important for interpreting time-to-event and secondary outcome estimates, but should not be inferred from the enrollment count or study status.
The record therefore permits a description of the intended outcomes, but not a full appraisal of multiplicity control, missing-data handling, or the population used in analysis. Numerical results for the secondary outcomes are not reported in the registry record.
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 |
|---|---|---|---|
| Trastuzumab, Bevacizumab, and Docetaxel | 0 | 26 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Trastuzumab, Bevacizumab, and Docetaxel | 26 of 26 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Trastuzumab, Bevacizumab, and Docetaxel |
|---|---|---|
| Infection | Infections and infestations | 24 of 26 |
| Fatigue | General disorders | 24 of 26 |
| Epistaxis | Respiratory, thoracic and mediastinal disorders | 22 of 26 |
| Arthralgia | Musculoskeletal and connective tissue disorders | 21 of 26 |
| Myalgia | Musculoskeletal and connective tissue disorders | 19 of 26 |
| Diarrhea | Gastrointestinal disorders | 19 of 26 |
| Mucositis | Gastrointestinal disorders | 19 of 26 |
| Nausea | Gastrointestinal disorders | 18 of 26 |
| Dyspnea | Respiratory, thoracic and mediastinal disorders | 16 of 26 |
| Headaches | Nervous system disorders | 15 of 26 |
The posted safety figures list one treatment group, with 26 participants at risk for serious adverse events and 0 affected. For other adverse events, the group lists 26 at risk and 26 affected. These are participant counts in the registry record. They do not give the event types, severity grades, timing, duration, or whether an event was judged related to treatment.
No serious adverse event terms are listed. The death count is not reported in the registry record. The figure of 0 affected for serious adverse events should be read as the posted count for that category, not as proof that no safety events of any kind occurred. The figure of 26 affected for other adverse events means all 26 participants listed at risk in that category are listed as affected; the record does not say whether each participant had one event or multiple events.
In general, adverse event counts require context about definitions, observation time, ascertainment, and completeness of reporting. Those details are not available. The safety figures are therefore a limited summary rather than a comprehensive account of safety. They cannot be used to compare safety with another regimen because no comparator group is described.
12. What the Result Does, and Does Not, Mean
This record shows that a phase II study of trastuzumab, bevacizumab, and docetaxel was completed and lists 26 participants in a single treatment group. It states that the study aimed to evaluate PFS and safety, and describes a single-stage design based on PFS at twelve months. It also lists secondary outcomes involving CTCs, CECs, and clinical benefit.
The registry record does not report the observed median PFS, its 95% confidence interval, the proportion progression-free at twelve months, or numerical findings for the secondary outcomes. It therefore does not show whether the planned PFS benchmark was met. The design’s planned values and decision threshold describe what the trial intended to assess; they are not results. The planned total sample size of 39 and the enrollment of 26 are both recorded, but the reason for the difference is not reported.
Since there is no comparator group, the trial cannot provide a randomized estimate of how outcomes differ between this regimen and another treatment. Even if within-group results were available, they would describe observed outcomes in this study rather than establish what would have happened to the same participants under a different treatment. The posted safety counts are also limited: they do not describe specific events, severity, or attribution.
These omissions do not establish that the regimen had favorable or unfavorable outcomes. They mean that the registry information is insufficient to quantify the primary efficacy result or fully characterize safety. A reader should distinguish the stated objectives and design from outcome evidence, and should not treat completion status or a planned design threshold as a finding.
13. Why This Trial Matters Statistically
This trial is statistically notable for the way its registry description connects a time-to-event objective with a single-stage phase II decision design. The record explains why the investigators chose not to wait for a first-stage PFS assessment, then states reference values for PFS at twelve months and a planned decision threshold. That makes the distinction between design assumptions and observed results especially important: planned benchmarks describe the question the study set out to answer, not the answer itself.
The design also illustrates a common limitation of single-group studies. A single group can support descriptive summaries, including a time-to-event estimate if results and follow-up data are reported, but it does not provide a randomized comparison. The registry lists allocation as NA and the model as single group, so there is no like-for-like control arm in the record. The scope of any conclusions must reflect that structure.
There is also a clear reporting issue for statistical interpretation. The registry lists a planned total sample size of 39 and enrollment of 26, yet does not explain the difference or report the primary PFS estimate. It lists four outcome measures and zero analyses, without a statistical analysis plan, missing-data methods, or analysis populations. This makes it difficult to assess how the intended design was carried out or how results should be evaluated.
Finally, the example shows why a completed status is not the same as a reported result. The record contains design information and limited safety counts, but not the key efficacy estimate. Statistical interpretation depends not only on the design but also on transparent reporting of estimates, uncertainty, and analysis methods.
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 principal limitation of the registry information is that the primary PFS result is not reported. The record names median PFS and a 95% confidence interval but gives neither the estimate nor the interval. It also does not report the PFS proportion at twelve months, which is central to the stated design benchmarks. As a result, the efficacy objective cannot be evaluated from this record.
The study has a single-group design and no comparator. Any outcomes that were observed could not be interpreted as a randomized contrast with another treatment. The registry lists enrollment of 26 while the design description states a planned total sample size of 39; the reason for this difference is not reported. It is also not clear from the registry whether the specified decision rule was applied.
Important endpoint details are missing, including the operational definition of progression, assessment schedule, censoring rules, and follow-up completeness. Analysis populations, missing-data procedures, and statistical methods are not reported in the registry record. The record also does not report numerical results for the listed secondary outcomes or explain how multiple outcomes and analyses were handled.
Safety reporting is limited to group-level counts. Specific serious adverse event terms are absent, the death count is not reported, and the other adverse event count has no accompanying descriptions of event type, severity, or attribution. These limitations constrain interpretation of both efficacy and safety; they do not imply that unreported findings were favorable or unfavorable.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Trastuzumab (Herceptin), Bevacizumab, and Docetaxel (Taxotere) Trial in Stage IV Metastatic Breast Cancer (MBC) Patients — NCT00428922.
- Registry record last updated 2018-08-09; status last verified 2018-07.
- Results first posted 2016-02-12.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
The registry record describes a completed phase II, single-group study of trastuzumab, bevacizumab, and docetaxel for people with stage IV metastatic breast cancer. Enrollment is listed as 26, allocation as NA, and masking as none. The stated primary objectives were PFS and safety; the primary outcome is described as median PFS in months with a 95% confidence interval, over a timeframe of up to 3 years.
The design description states a single-stage plan, PFS benchmarks at twelve months, and a planned total sample size of 39. The record does not report the observed median PFS, its confidence interval, or numerical results for the listed secondary outcomes. It lists 26 participants at risk and 0 affected for serious adverse events, and 26 at risk and 26 affected for other adverse events. Serious event terms are not listed, and the death count is not reported.
The record does not provide the analysis methods, missing-data procedures, or analysis populations. It describes study aims and design but leaves the principal efficacy result unavailable for interpretation.