This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for A Phase III Trial For Patients With Metastatic Breast Cancer (NCT00191152), a randomized phase 3 study. The primary outcome is Time to Disease Progression (Initial Treatment).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00191152 |
| Phase | Phase 3 |
| Condition | Breast Cancer, Breast Neoplasms, Cancer of the Breast |
| Allocation | Randomized |
| Design model | Crossover |
| Masking | None (open label) |
| Enrollment | 475 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Eli Lilly and Company |
| Results posted | Yes |
2. Clinical Question
Population
Participants with metastatic breast cancer entered a randomized trial of two drug combinations. The registry describes the analysis population as all randomized participants, with 239 assigned to gemcitabine plus docetaxel and 236 assigned to docetaxel plus capecitabine.
Intervention
The initial-treatment regimen was gemcitabine plus docetaxel. The registry describes gemcitabine as intravenous treatment on days 1 and 8 and docetaxel as intravenous treatment on day 1, repeated every three weeks.
Comparator
The comparator was docetaxel plus capecitabine. Docetaxel was given intravenously on day 1 and capecitabine orally twice daily on days 1 through 14, with the regimen repeated every three weeks.
Primary question
Among randomized participants, how long was the interval from randomization to the first documented disease progression or death due to the study disease during initial treatment? The reported comparison used a log-rank test.
The trial also specified crossover to the alternate drug combination after progression: participants initially assigned gemcitabine plus docetaxel could receive capecitabine, while those initially assigned docetaxel plus capecitabine could receive gemcitabine. The primary question concerns the initial-treatment period, not the full sequence of initial and crossover treatments.
The registry reports median time to disease progression of 9.28 months for gemcitabine plus docetaxel and 8.88 months for docetaxel plus capecitabine. Their respective 95% confidence intervals are 7.73 to 10.79 months and 7.37 to 11.05 months. The reported log-rank p-value for the comparison is 0.385. These figures describe the posted endpoint results; they do not by themselves establish equivalence or determine the effect of either regimen after crossover.
3. Trial Design
This was a phase III randomized trial with a crossover model. The registry lists an enrollment of 475 and reports 239 participants in the gemcitabine plus docetaxel group and 236 in the docetaxel plus capecitabine group for the primary endpoint. The allocation was randomized, and masking was listed as none.
The study compared two initial-treatment combinations. Gemcitabine plus docetaxel was compared with docetaxel plus capecitabine. The regimens were scheduled on three-week cycles. The registry describes the gemcitabine combination as gemcitabine 1000 mg/m2 intravenously over 30 minutes on days 1 and 8, together with docetaxel 75 mg/m2 intravenously on day 1. The capecitabine combination included docetaxel 75 mgm/m2 intravenously on day 1 and capecitabine 1000 mg/m2 orally twice daily on days 1 through 14.
Progression initiated the crossover plan. Participants who progressed on gemcitabine plus docetaxel were to receive capecitabine as described for the comparator regimen; participants who progressed on docetaxel plus capecitabine were to receive gemcitabine as described for the other regimen. The primary endpoint is specifically defined for initial treatment, and its censoring rules include the first dose of crossover treatment.
The registry lists the study as completed, with a start date of 2002-02 and primary completion in 2008-11. It does not report the detailed randomization procedure, stratification factors, treatment-adherence summaries, or the rationale for the enrollment target. The record identifies 12 secondary outcomes, including progression-free survival, overall survival, duration of response, and response outcomes during initial or crossover treatment. These additional outcomes address questions distinct from the primary initial-treatment time-to-progression comparison.
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: Not all participants who completed initial treatment went on to crossover treatment. Per protocol, participants had the option to go off study without receiving crossover treatment.
Initial Treatment
| Stage | Gemcitabine Plus Docetaxel | Docetaxel Plus Capecitabine |
|---|---|---|
| STARTED | 239 | 236 |
| Received Initial Treatment | 236 | 227 |
| COMPLETED | 98 | 83 |
| NOT COMPLETED | 141 | 153 |
Reasons for not completing this period:
| Reason | Gemcitabine Plus Docetaxel | Docetaxel Plus Capecitabine |
|---|---|---|
| Adverse Event | 43 | 67 |
| Physician Decision | 40 | 31 |
| Withdrawal by Subject | 40 | 28 |
| Lost to Follow-up | 0 | 6 |
| Other | 18 | 21 |
Crossover Treatment
| Stage | Gemcitabine Plus Docetaxel | Docetaxel Plus Capecitabine |
|---|---|---|
| STARTED | 77 | 81 |
| Received Treatment | 76 | 80 |
| COMPLETED | 50 | 53 |
| NOT COMPLETED | 27 | 28 |
Reasons for not completing this period:
| Reason | Gemcitabine Plus Docetaxel | Docetaxel Plus Capecitabine |
|---|---|---|
| Adverse Event | 8 | 8 |
| Physician Decision | 7 | 7 |
| Withdrawal by Subject | 6 | 9 |
| Lost to Follow-up | 2 | 1 |
| Other | 4 | 3 |
Analysis population for the primary outcome, as defined in the registry: Intent-to-treat (ITT) population: all randomized participants. Censored participants in initial treatment: 68 gemcitabine/docetaxel arm; 83 docetaxel/capecitabine arm.
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 | Gemcitabine Plus Docetaxel | Docetaxel Plus Capecitabine | Total |
|---|---|---|---|---|
| Participants analysed | 239 | 236 | 475 | |
| Age Continuous | years | 55.8 (SD 11.77) | 54.6 (SD 11.60) | 55.2 (SD 11.69) |
| Sex: Female, Male: Female | Participants | 237 | 1 | 238 |
| Sex: Female, Male: Male | Participants | 2 | 235 | 237 |
| Region of Enrollment: United States | participants | 173 | 166 | 339 |
| Region of Enrollment: Taiwan | participants | 15 | 18 | 33 |
| Region of Enrollment: Mexico | participants | 14 | 15 | 29 |
| Region of Enrollment: Puerto Rico | participants | 4 | 1 | 5 |
| Region of Enrollment: Argentina | participants | 11 | 13 | 24 |
| Region of Enrollment: Brazil | participants | 1 | 1 | 2 |
| Region of Enrollment: Australia | participants | 11 | 12 | 23 |
| Region of Enrollment: Korea, Republic of | participants | 10 | 10 | 20 |
| Karnofsky Performance Status-Baseline: <=60 Needs increasing assistance up to Death (0) | units on a scale | 0 | 0 | 0 |
| Karnofsky Performance Status-Baseline: 70 - Unable to carry on normal activity | units on a scale | 16 | 15 | 31 |
| Karnofsky Performance Status-Baseline: 80 - Activity with effort; some signs of disease | units on a scale | 44 | 40 | 84 |
| Karnofsky Performance Status-Baseline: 90 - Normal activity; minor signs of disease | units on a scale | 101 | 101 | 202 |
| Karnofsky Performance Status-Baseline: 100 - Normal no complaints; no evidence of disease | units on a scale | 74 | 75 | 149 |
| Karnofsky Performance Status-Baseline: Missing | units on a scale | 4 | 5 | 9 |
| Race/Ethnicity: Caucasian | participants | 160 | 158 | 318 |
| Race/Ethnicity: African Descent | participants | 23 | 12 | 35 |
| Race/Ethnicity: Oriental | participants | 28 | 30 | 58 |
| Race/Ethnicity: Hispanic | participants | 26 | 36 | 62 |
| Race/Ethnicity: Other | participants | 2 | 0 | 2 |
6. Primary Endpoint
The registry lists the primary outcome as Time to Disease Progression (Initial Treatment), measured over Randomization date to the earliest date of first documented disease progression date or the date of death if the participant died due to study disease (up to 82 months).
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | 95% Confidence Interval |
| Unit | months |
| Endpoint classification | Time-to-Event Analysis |
The primary endpoint was time to disease progression during initial treatment, measured in months. It was defined as the time from randomization to the earliest of first documented disease progression or death due to the study disease. The registry describes the observation period as up to 82 months.
This is a time-to-event endpoint: the outcome is the time until a specified event, rather than a measurement taken at one fixed visit. It can use information from participants whose event has not been observed by the end of their follow-up, provided their follow-up is handled as censored. In this trial, the registry says censoring occurred at the earliest of death not due to the study disease, last contact while alive without progression, start of other anti-tumor therapy, or first dose of crossover treatment.
A median time-to-event value describes the time by which the estimated event distribution reaches its midpoint. It is not the average time, and it does not describe the experience of every participant. The registry reports medians and 95% confidence intervals for each randomized group. The endpoint is useful for comparing the timing of progression or disease-related death while accounting for differing follow-up and censoring, but the interpretation depends on how censoring and events were recorded and analyzed.
Because crossover begins after progression, the primary endpoint focuses on the initial assigned regimen. It does not measure the total duration or outcome of the subsequent treatment sequence.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The reported median time to disease progression was 9.28 months for gemcitabine plus docetaxel, with a 95% confidence interval from 7.73 to 10.79 months. For docetaxel plus capecitabine, the median was 8.88 months, with a 95% confidence interval from 7.37 to 11.05 months. The reported log-rank p-value for the comparison was 0.385.
The medians are estimates of the midpoint of each group’s time-to-event distribution. Their confidence intervals communicate uncertainty in those estimates. A confidence interval is not a range containing the individual outcomes of most participants; it describes statistical uncertainty about the estimated quantity under the analysis method. The interval estimates overlap, but overlap alone is not a formal test of the between-group comparison. The registry’s reported log-rank analysis is the relevant posted comparison result.
The log-rank p-value summarizes how compatible the observed separation between the groups’ time-to-event patterns is with a null hypothesis of no difference, under the test’s assumptions. A p-value of 0.385 is not a probability that the null hypothesis is true, nor does it quantify the size of a treatment effect. It does not establish that the regimens are equivalent. Demonstrating equivalence or non-inferiority would require a prespecified margin and an analysis designed for that question; such details are not reported in the registry record.
The group medians are close as point estimates, but the registry does not report a hazard ratio or a confidence interval for a between-group effect in the primary results. Medians alone do not show the full shape of the event-time distributions. They cannot establish whether any difference was consistent throughout follow-up, whether the curves crossed, or how the event patterns varied over time. Those details are not reported in the registry record.
There were 239 and 236 participants in the respective primary-endpoint groups. The registry identifies the analysis population as all randomized participants. It also reports 68 censored participants in the gemcitabine plus docetaxel group and 83 in the docetaxel plus capecitabine group. Censoring means that the event time was not observed under the endpoint definition before a listed censoring event. These counts do not, on their own, explain why each participant was censored or how censoring affected the estimate.
The result therefore supports a focused reading: the registry reports group-specific median times and a log-rank test for initial treatment. It does not provide enough detail to infer equivalence, to characterize every part of the time-to-event distributions, or to assess outcomes after crossover from this primary result alone.
9. Statistical Methods Explained
Time-to-event methods are used when the outcome is the time until an event, such as disease progression or death under a defined endpoint. Participants may have different lengths of follow-up. Some have the event observed, while others leave observation without an event being recorded for that endpoint. Such observations are censored rather than treated as if the event occurred at the time follow-up ended.
What does the median represent?
A median time-to-event estimate marks the point at which the estimated event distribution reaches its midpoint. It is distinct from a mean, which averages observed event times, and it does not imply that every participant experienced the event at that time. The registry reports a median of 9.28 months for gemcitabine plus docetaxel and 8.88 months for docetaxel plus capecitabine. Each estimate has a 95% confidence interval: 7.73 to 10.79 months and 7.37 to 11.05 months, respectively.
A confidence interval represents uncertainty in an estimate under the statistical procedure used. Its width reflects the precision of that estimate, but it is not a guarantee about an individual participant’s outcome. The registry does not report the detailed procedure used to construct these intervals. The median estimates and their intervals are group-specific; they are not themselves a confidence interval for the difference between groups.
How does censoring enter the analysis?
The endpoint definition treats progression or death due to the study disease as an event, whichever occurs first. The registry says participants were censored at the earliest of death not due to the study disease, last contact while alive without progression, start of other anti-tumor therapy, or first dose of crossover treatment. Censoring retains the information that a participant remained under observation and event-free up to a particular point, without claiming that an event occurred then.
Standard time-to-event analyses generally rely on assumptions about censoring. In general, the methods are most straightforward to interpret when censoring is not related to a participant’s future event time after accounting for the analysis. If censoring is associated with prognosis, the resulting estimates can be difficult to interpret. The registry provides the censoring rules and the counts of censored participants, but does not report reasons for censoring by participant or analyses assessing the censoring assumptions.
What does the log-rank test compare?
The registry reports a log-rank test with p = 0.385. In general, the log-rank test compares event patterns over follow-up between groups, using information about when events and censoring occur. It is not a test of the two reported medians alone. Its result depends on the event-time information across follow-up, not only on the median values.
A p-value describes the compatibility of the observed data with a specified null model, given the analysis method and its assumptions. It is not the probability that the null model is correct, and it does not measure the size or clinical importance of a difference. The registry does not report a hazard ratio for this primary comparison, so the log-rank p-value should not be read as an estimate of the relative event rate or as a direct measure of effect magnitude.
How should the randomized groups be interpreted?
The primary population is described as the intent-to-treat population, meaning all randomized participants. This approach analyzes participants according to their randomized group and preserves the original randomized comparison in the analysis population. The reported endpoint group sizes are 239 and 236. Crossover was planned after progression, and the primary endpoint’s censoring rules include the start of crossover treatment. Thus, the endpoint is an initial-treatment comparison rather than a comparison of complete treatment sequences.
The registry record does not report whether other analysis populations were used for this endpoint, how protocol deviations were handled, or whether adjusted analyses were conducted. It also does not report the detailed statistical model beyond the log-rank test listed for the comparison.
What can planning illustrations say?
Sample-size calculations based on an observed effect are planning illustrations, not observed power and not evidence about the original trial’s design. The stated illustration assumptions are a two-sided significance level of 0.05, equal allocation, and a normal approximation; the effect to detect is a stated fraction of the observed effect. For time-to-event calculations, the quantity is the total number of events, using the Schoenfeld approach. These assumptions describe an illustration, not the trial’s own sample-size justification. The sample-size justification and its underlying design assumptions are not reported in the registry record.
More generally, over-dispersion refers to variability greater than a chosen statistical model expects. When present, it can make uncertainty estimates too optimistic if the model does not account for it. The primary endpoint is a time-to-event outcome analyzed with a log-rank test, and the registry does not report an over-dispersion assessment or a model-based adjustment for it. That concept should not be mistaken for a feature established in this trial.
10. Analyses Reported by the Sponsor
| Method | Estimate | 95% CI | P-value |
|---|---|---|---|
| Log Rank | not reported | 0.385 |
The primary comparison reported in the registry is a log-rank test with p = 0.385. The registry also reports the two group medians and their 95% confidence intervals: 9.28 months (7.73 to 10.79) for gemcitabine plus docetaxel and 8.88 months (7.37 to 11.05) for docetaxel plus capecitabine.
A separate recalculated between-group estimate is not reported for this median time-to-event endpoint. The two group medians and their confidence intervals are not sufficient to reconstruct the event-time data needed to reproduce a log-rank test or derive a hazard ratio. The registry does not report a hazard ratio for this primary comparison. The sponsor’s reported test is therefore the available formal comparison in the record; the medians should be read as descriptive group estimates, not as a substitute for that test.
No discrepancy is identified between a sponsor analysis and a recalculated estimate in the registry information for this endpoint. The posted result does not establish equivalence, and the reported p-value should not be interpreted as the probability that there is no difference. It is a test result under the log-rank analysis.
11. Multiplicity, Missing Data and Analysis Populations
The registry lists 13 outcome measures and 13 analyses, with 12 secondary outcomes in addition to the primary endpoint. The secondary outcomes include progression-free survival, time to disease progression after crossover, duration of response, overall survival, and best overall response during initial or crossover treatment. A trial with multiple outcomes or comparisons raises a multiplicity question: when many statistical tests are performed, the chance of at least one apparently unusual result can increase. Whether and how that concern was addressed is not reported in the registry record.
No multiplicity adjustment, testing hierarchy, or prespecified strategy for interpreting the family of outcomes is reported. The primary log-rank p-value should therefore be read as the reported result for that endpoint, not as evidence that all listed outcomes were evaluated under a single error-controlled procedure. The registry does not report interim analyses or stopping rules for the primary comparison.
The primary analysis population is described as intent-to-treat, including all randomized participants. The registry reports 239 participants assigned to gemcitabine plus docetaxel and 236 assigned to docetaxel plus capecitabine. It also reports 68 and 83 censored participants, respectively, for initial treatment. Censoring is part of the time-to-event analysis and is distinct from a general account of missing data.
The endpoint definition identifies specific censoring events, including last contact without progression and first dose of crossover treatment. It does not report a fuller accounting of missing measurements, loss to follow-up by reason, or sensitivity analyses for missingness and censoring. Detailed handling of missing data outside the stated time-to-event censoring rules is not reported in the registry record. Likewise, the record does not describe the statistical analysis plan in enough detail to determine whether all secondary analyses used the same population or methods.
12. 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 |
|---|---|---|---|
| Gemcitabine Plus Docetaxel | 72 | 237 | 30.4% |
| Docetaxel Plus Capecitabine | 55 | 226 | 24.3% |
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 |
|---|---|
| Gemcitabine Plus Docetaxel | 233 of 237 |
| Docetaxel Plus Capecitabine | 221 of 226 |
Most frequent serious adverse event terms
| Event term | Organ system | Gemcitabine Plus Docetaxel | Docetaxel Plus Capecitabine |
|---|---|---|---|
| Neutropenia | Blood and lymphatic system disorders | 25 of 237 | 7 of 226 |
| Febrile neutropenia | Blood and lymphatic system disorders | 9 of 237 | 9 of 226 |
| Pyrexia | General disorders | 4 of 237 | 5 of 226 |
| Leukopenia | Blood and lymphatic system disorders | 6 of 237 | 2 of 226 |
| Vomiting | Gastrointestinal disorders | 4 of 237 | 3 of 226 |
| Diarrhoea | Gastrointestinal disorders | 2 of 237 | 4 of 226 |
| Pneumonia | Infections and infestations | 3 of 237 | 3 of 226 |
| Dehydration | Metabolism and nutrition disorders | 4 of 237 | 2 of 226 |
| Dyspnoea | Respiratory, thoracic and mediastinal disorders | 4 of 237 | 2 of 226 |
| Fatigue | General disorders | 3 of 237 | 2 of 226 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Gemcitabine Plus Docetaxel | Docetaxel Plus Capecitabine |
|---|---|---|---|
| Neutropenia | Blood and lymphatic system disorders | 193 of 237 | 73 of 226 |
| Fatigue | General disorders | 129 of 237 | 120 of 226 |
| Nausea | Gastrointestinal disorders | 113 of 237 | 118 of 226 |
| Diarrhoea | Gastrointestinal disorders | 111 of 237 | 108 of 226 |
| Alopecia | Skin and subcutaneous tissue disorders | 86 of 237 | 98 of 226 |
| Anaemia | Blood and lymphatic system disorders | 113 of 237 | 59 of 226 |
| Peripheral sensory neuropathy | Nervous system disorders | 78 of 237 | 83 of 226 |
| Vomiting | Gastrointestinal disorders | 71 of 237 | 74 of 226 |
| Palmar-plantar erythrodysaesthesia syndrome | Skin and subcutaneous tissue disorders | 15 of 237 | 129 of 226 |
| Anorexia | Metabolism and nutrition disorders | 59 of 237 | 59 of 226 |
Serious events with the highest arm-level rate: neutropenia (10.5%), febrile neutropenia (4.0%), leukopenia (2.5%), pyrexia (2.2%), pulmonary embolism (2.1%).
The registry reports serious adverse events for 237 participants at risk in the gemcitabine plus docetaxel group, with 72 affected, and 226 at risk in the docetaxel plus capecitabine group, with 55 affected. These are participant counts as recorded; they should not be interpreted as treatment effects without further analysis. The registry also lists other adverse events for 233 of 237 and 221 of 226 participants, respectively.
Among the listed serious adverse event terms, the registry reports neutropenia at 10.5%, febrile neutropenia at 4.0%, leukopenia at 2.5%, pyrexia at 2.2%, pulmonary embolism at 2.1%, and diarrhoea at 1.8%. The record does not specify, in the information available for these terms, whether each percentage is arm-specific or the denominator used. These figures should not be assigned to a treatment group or used to infer a comparative risk.
Death counts for the adverse-event summary are not reported in the registry record. The figures do not establish causation, and no statistical comparison of serious adverse events is listed. They describe reported safety counts and terms, with important detail about attribution and denominators not reported.
13. What the Result Does, and Does Not, Mean
The primary results describe time to progression or disease-related death during initial treatment in randomized groups. The registry reports median times of 9.28 months for gemcitabine plus docetaxel and 8.88 months for docetaxel plus capecitabine, with respective 95% confidence intervals of 7.73 to 10.79 months and 7.37 to 11.05 months. Its reported log-rank p-value is 0.385.
These results do not establish that the regimens are equivalent. A failure to show a statistically compelling difference is not the same as evidence that outcomes are identical or sufficiently similar. Equivalence or non-inferiority requires a defined margin and a study analysis designed for that purpose; those details are not reported in the registry record. The p-value does not give the probability that either regimen is better, and the group medians do not describe all features of the event-time distributions.
The endpoint concerns initial treatment. Participants could cross over after progression, and starting crossover treatment was a censoring event for the primary endpoint. The primary result therefore does not answer how the full sequence of initial and crossover therapies affected outcomes. Separate crossover outcomes are listed among the registry’s secondary outcomes, but their results are not part of the primary figures.
The record identifies the analysis population as all randomized participants, but it does not provide a hazard ratio for the primary comparison, event counts, detailed event-time distributions, or a full account of censoring reasons. These omissions limit assessment of effect magnitude, precision for a between-group contrast, and the robustness of the analysis assumptions.
Accordingly, the appropriate reading is narrow: the reported initial-treatment medians and log-rank test summarize the primary endpoint as entered in the registry. They are not, by themselves, a complete account of comparative efficacy, safety, the crossover sequence, or the broader clinical question.
14. Why This Trial Matters Statistically
This trial illustrates why time-to-event results should not be reduced to a comparison of two medians. The endpoint incorporated both documented progression and death due to the study disease, while accounting for participants whose event was not observed before a defined censoring point. The log-rank test uses event-time information across follow-up, so its result addresses more than the numerical distance between the medians.
It also demonstrates the importance of keeping an endpoint’s treatment period clear. The study planned crossover after progression, but the primary endpoint was limited to initial treatment and censored at the first crossover dose. Outcomes under a treatment sequence are not interchangeable with outcomes under the initial randomized assignment alone.
The registry provides group-specific medians, confidence intervals, group sizes, censoring counts, and a log-rank p-value. It does not report a hazard ratio for the primary comparison. This distinction matters: a test result can address evidence against a null hypothesis without supplying an estimate of relative effect or a confidence interval for that effect. The reported group summaries should not be stretched into an unreported contrast.
Finally, the record lists multiple secondary outcomes but does not describe a multiplicity strategy or a detailed statistical analysis plan. That makes it important to distinguish the one posted primary comparison from a broader set of possible outcome questions. Reading the trial statistically requires attention to the estimand, censoring, crossover, and the limits of what the registry records—not just to the point estimates.
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 registry record leaves several details unavailable for interpreting the primary result. It does not report a hazard ratio or confidence interval for the between-group comparison, event counts, or detailed event-time distributions. The medians and their confidence intervals therefore cannot describe the full pattern of outcomes or independently quantify a comparative effect.
The endpoint includes specified censoring rules, and the registry reports 68 censored participants in the gemcitabine plus docetaxel group and 83 in the docetaxel plus capecitabine group. Reasons for censoring are not broken down in the information recorded. The record does not report sensitivity analyses assessing how censoring may have influenced the results, or a more complete account of missing data.
Crossover was planned after progression, and crossover initiation was a censoring event for the primary endpoint. This makes the primary result a comparison of initial treatment rather than the complete treatment sequence. The record lists secondary outcomes for crossover treatment, but those results are not included in the primary outcome information.
The registry does not report a multiplicity adjustment or hierarchy for the 12 secondary outcomes, interim analyses, detailed randomization procedures, stratification factors, or the trial’s sample-size justification. It also does not provide further eligibility criteria or enough safety detail to determine the arm-specific denominators for the listed serious adverse event percentages. These are reporting limitations in the registry record; they do not establish that such procedures or information were absent from other study materials.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: A Phase III Trial For Patients With Metastatic Breast Cancer — NCT00191152.
- Registry record last updated 2009-12-24; status last verified 2009-12.
- Results first posted 2009-12-08.
- 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.
19. Record Summary
NCT00191152 is a completed randomized phase III trial in metastatic breast cancer, with an enrollment of 475. It compared initial gemcitabine plus docetaxel with docetaxel plus capecitabine and planned crossover to the alternate agent after progression. Masking was listed as none.
The primary endpoint was time to disease progression during initial treatment, defined by progression or death due to the study disease. The registry reports medians of 9.28 months and 8.88 months, with 95% confidence intervals of 7.73 to 10.79 months and 7.37 to 11.05 months. The reported log-rank p-value is 0.385.
The primary population was all randomized participants. The record lists 12 secondary outcomes, but does not report a hazard ratio for the primary comparison or a multiplicity strategy. Crossover and censoring rules are central to interpreting the endpoint as an initial-treatment result.