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 Allogeneic Hematopoietic Stem Cell Transplantation With Bevacizumab for Advanced Solid Tumor (NCT00523809), a na phase 2 study. The primary outcome is Progression-free Survival (PFS).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00523809 |
| Phase | Phase 2 |
| Condition | Breast Cancer, Ovarian Cancer |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 5 |
| Arms in the primary outcome | n/a |
| Lead sponsor | M.D. Anderson Cancer Center |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned patients with advanced solid tumors, with breast cancer and ovarian cancer listed as conditions. The registry record does not give further eligibility details or describe the characteristics of enrolled participants. Enrollment was 5.
Intervention
The planned treatment combined bevacizumab with fludarabine, melphalan, thymoglobulin, and allogeneic hematopoietic stem cell transplantation. The record describes bevacizumab on Day 1, chemotherapy over the specified days, thymoglobulin on Days - 3 through -1, and transplantation on Day 8.
Comparator
The study had a single group and no comparator group. It therefore was not designed as a randomized or controlled comparison of the regimen against another treatment in this record. Allocation is listed as NA.
Primary question
The stated primary endpoint was progression-free survival: the number of participants with no disease progression or death for any reason during the first 100 days following transplantation. The study also aimed to assess safety. The registry record says the study objectives were not met and the primary analysis was not performed, so it does not answer whether the regimen changed progression-free survival.
3. Trial Design
This was a phase 2, single-group study sponsored by M.D. Anderson Cancer Center. The record lists breast cancer and ovarian cancer as conditions and describes the intended population more broadly as patients with an advanced solid tumor. Enrollment was 5. The study began in 2007-08, had a primary completion date of 2011-10, and is listed as terminated.
The treatment group was named Bevacizumab + Fludarabine + Melphalan. Its regimen description also includes thymoglobulin and allogeneic hematopoietic stem cell transplantation. Bevacizumab was specified as 10 mg/kg intravenously on Day 1; fludarabine as 25 mg/m^2 intravenously daily over 5 days; and melphalan as 70 mg/m^2 intravenously daily over 2 days. Thymoglobulin was specified at 0.5 mg/kg on Day - 3, 1.5 mg/kg on Day - 2, and 2 mg/kg on Day -1, followed by transplantation on Day 8.
Allocation is listed as NA, masking as none, and the model as single group. Thus, the record describes neither random assignment nor a masked comparison. Without a concurrent comparator, any outcome observed in this group would not by itself distinguish the treatment regimen's effects from the course of disease, other care, or chance variation. The registry record does not report a protocol rationale for the regimen or a sample-size justification.
The stated goal was to learn whether bevacizumab with standard chemotherapy and a blood stem cell transplant could help shrink a tumor or slow its growth, and to study safety. The recorded primary outcome was progression-free survival during the first 100 days following transplantation. Participants were to be followed every 3 months for the first year. The registry record states that the study objectives were not met and that analysis was not performed.
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 | Bevacizumab + Fludarabine + Melphalan |
|---|---|
| STARTED | 5 |
| COMPLETED | 5 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: Study objectives were not meet, analysis was not performed.
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 | Bevacizumab + Fludarabine + Melphalan |
|---|---|---|
| Participants analysed | 5 | |
| Age Continuous | years | 55 (45 to 58) |
| Sex: Female, Male: Female | Participants | 5 |
| Sex: Female, Male: Male | Participants | 0 |
| Region of Enrollment: United States | participants | 5 |
6. Primary Endpoint
The registry lists the primary outcome as Progression-free Survival (PFS), measured over 100 days after transplant.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was progression-free survival (PFS), defined in the registry record as the number of participants with no disease progression or death for any reason during the first 100 days following transplantation. This is a time-to-event concept: progression or death marks an event, while a participant who has experienced neither remains progression-free up to the relevant follow-up time. In this record, however, the endpoint is described as a count at a stated time rather than accompanied by an individual event-time analysis.
PFS is used in clinical research to capture whether disease progression or death has occurred during a specified follow-up period. Including death from any cause means that death is counted as an event even if progression has not been recorded. As a general statistical point, an endpoint of this kind can summarize disease control and survival experience together, but its interpretation depends on complete and consistently assessed follow-up, clear event definitions, and a reported analysis.
The record says participants were followed every 3 months for the first year. It gives the endpoint timeframe as 100 days after transplant, but does not report endpoint results, event counts, or an analysis. It states that the study objectives were not met and the analysis was not performed. Consequently, the registry record does not establish how many participants met the PFS definition.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The most important statistical fact is that the registry record does not report an analysis of the primary endpoint. It explicitly states that the study objectives were not met and the analysis was not performed. Although the endpoint is defined and a follow-up schedule is described, no PFS count, estimate, uncertainty interval, or test result is reported. There is therefore no posted primary efficacy result to interpret.
The study enrolled 5 participants and used a single-group design. That small enrollment means any result, had it been reported, would have been based on limited information and would generally be imprecise. More fundamentally, the lack of a comparator prevents a direct estimate of how outcomes differed from another treatment or from a control condition. A single-group observation cannot separate a treatment-associated outcome from other influences, including the underlying illness and the circumstances of care.
The registry lists serious adverse events affecting 4 of 5 participants at risk and other adverse events affecting 5 of 5 at risk. These counts describe reported safety events in this group; they are not a comparison of risks between treatment options. The serious adverse event terms listed include diverticulitis, death, cardiac toxicity with reduced ejection fraction, and headache, each with a reported frequency of 20.0%. The record does not provide event timing, severity grades, attribution to treatment, or participant-level detail. The deaths field is null, so a separate count of deaths is not reported, even though Death appears among the serious adverse event terms.
These safety counts should be read as descriptive registry entries rather than precise estimates of frequency in a broader population. In a group of this size, each participant's experience substantially affects the overall description. Also, the registry does not report whether all participants had the same duration of safety observation or how adverse events were collected.
The listed termination status and statement that objectives were not met are relevant context, but they do not explain why the study ended or why analysis was not performed. The reason for termination is not reported in the registry record. Nor does the status alone establish whether the regimen was beneficial or harmful. The record supports describing the planned design, endpoint, enrollment, and reported adverse-event counts, but not drawing a conclusion about efficacy or comparative safety.
9. Statistical Methods Explained
What can be inferred from the design?
As a general statistical concept, a single-group study describes outcomes among participants receiving the study regimen. It does not create a concurrent comparison group. Randomized allocation, when used, is a method for balancing known and unknown prognostic factors on average between groups; allocation is listed as NA in this record, and the model is single group. Therefore, a treatment contrast is not available from the registry record.
A single-group design can still document whether specified outcomes occurred among enrolled participants. But an observed outcome cannot by itself establish what would have happened to the same participants under another treatment or without the regimen. Differences from expectations or historical experiences can be affected by patient selection, disease severity, follow-up, and other changes in care. These are general considerations, not additional findings about this study.
What does an unperformed analysis mean?
The registry record states that study objectives were not met and analysis was not performed. It lists one outcome measure and zero analyses. Thus, no inferential result for the primary endpoint is reported. There is no reported PFS estimate, standard error, confidence interval, hypothesis test, or adjusted analysis to interpret. These are not findings of no effect; they are absent because the record says the analysis was not performed.
In general, an estimate describes the outcome calculated from observed data, while a confidence interval describes the statistical uncertainty around that estimate under a specified method. A hypothesis test evaluates data against a defined null hypothesis under a specified analysis plan. None of those results can be reconstructed from the endpoint definition and enrollment count alone. The registry record also does not report participant-level outcome data, which would be needed for independent endpoint analyses.
How should the planning illustrations be read?
General sample-size calculations can illustrate how many participants might be needed to detect a specified effect under stated assumptions. The record describes an illustration based on the observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect. It also distinguishes calculations for time-to-event outcomes, which use total events, from other calculations, which use participants per arm.
These assumptions are not evidence that this trial was designed with those targets. The record explicitly describes the calculation as a planning illustration, not the trial's own design. It also gives no numeric planning outputs in the registry record excerpt summarized by the available study details, and the primary analysis was not performed. There is consequently no observed effect in the reported primary result on which a reader can base a substantive planning interpretation. Such illustrations must not be treated as observed power or as proof that the study could or could not detect a clinical effect.
Why does over-dispersion matter in general?
Over-dispersion is a general concern when outcome variability is greater than a statistical model assumes. If a model understates variability, its uncertainty estimates can be too small and inferential results can appear more decisive than warranted. Accounting for over-dispersion can widen uncertainty and change tests or planning calculations. The registry record does not report an over-dispersion assessment or a statistical model for the primary endpoint, so no conclusion about its relevance to this study is possible.
What is not reported about the analysis?
The registry record does not report a statistical analysis plan, the intended estimand, rules for censoring or handling incomplete follow-up, covariate adjustment, or interim analyses. An estimand is, in general, the precise treatment effect or outcome quantity a study intends to estimate, including how events and intercurrent events are handled. Those details matter because different analysis choices can produce different interpretations, especially for time-to-event outcomes.
There is also no reported endpoint analysis population, such as a defined group of enrolled or treated participants for whom the endpoint would be evaluated. Without analysis results or these methods, readers cannot assess whether the endpoint was evaluated as planned or whether the analysis accounted for follow-up and missing observations in a particular way. The proper statistical reading is limited to the design and details explicitly recorded, not an inferred or reconstructed treatment effect.
10. Multiplicity, Missing Data and Analysis Populations
Multiplicity arises when a study conducts several statistical tests or evaluates multiple outcomes, because the chance of at least one apparently noteworthy result can increase as tests accumulate. In general, a prespecified plan can identify the primary question and specify whether and how multiple comparisons will be addressed. This registry record lists one outcome measure and zero analyses. It does not report a statistical analysis plan, adjustment for multiplicity, or any inferential results. There is therefore no basis to assess a multiplicity procedure or to describe a set of tested hypotheses.
The primary outcome description defines progression-free survival during the first 100 days following transplantation and says participants were followed every 3 months for the first year. The record does not report the number with available outcome assessments, the completeness of follow-up, or how missing endpoint information would be handled. It also does not report reasons for missing data, withdrawal, or loss to follow-up. Those details are important because missing observations can affect which participants contribute to an endpoint estimate and can introduce bias if missingness is related to health status or outcome.
The analysis population is not reported in the registry record. It does not specify whether the planned analysis would include all enrolled participants, only those who received transplantation, or another defined group. No interim analysis plan is reported. The stated study status is terminated, but the reason for termination and its relationship, if any, to the planned analysis are not reported in the registry record.
Because the record says the analysis was not performed, there is no reported statistical result whose handling of multiplicity, missing data, or analysis populations can be evaluated. These omissions limit interpretation; they do not establish that any particular analysis choice was made.
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 |
|---|---|---|---|
| Bevacizumab + Fludarabine + Melphalan | 4 | 5 | 80.0% |
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 |
|---|---|
| Bevacizumab + Fludarabine + Melphalan | 5 of 5 |
Most frequent serious adverse event terms
| Event term | Organ system | Bevacizumab + Fludarabine + Melphalan |
|---|---|---|
| Diverticulitis | Gastrointestinal disorders | 1 of 5 |
| Death | Investigations | 1 of 5 |
| Cardiac toxicity, reduced ejection fraction | Cardiac disorders | 1 of 5 |
| Headache | General disorders | 1 of 5 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Bevacizumab + Fludarabine + Melphalan |
|---|---|---|
| Vaginal bleed | Reproductive system and breast disorders | 1 of 5 |
| Hot flash | Reproductive system and breast disorders | 1 of 5 |
| Vaginal itch | Reproductive system and breast disorders | 1 of 5 |
| Vaginal dryness | Reproductive system and breast disorders | 1 of 5 |
| Mild breast pain | Reproductive system and breast disorders | 1 of 5 |
| Face swelling | Reproductive system and breast disorders | 1 of 5 |
| Mild depression | Psychiatric disorders | 1 of 5 |
| Headache | General disorders | 1 of 5 |
| Abdominal tenderness | Investigations | 1 of 5 |
| Insomnia | Psychiatric disorders | 1 of 5 |
Serious events with the highest arm-level rate: diverticulitis (20.0%), death (20.0%), cardiac toxicity, reduced ejection fraction (20.0%), headache (20.0%).
The registry lists 5 participants at risk for serious adverse events, with 4 affected. For other adverse events, 5 participants were at risk and 5 were affected. These are descriptive counts for the study group, not comparative estimates against a control group. The serious adverse event terms listed are diverticulitis, death, cardiac toxicity with reduced ejection fraction, and headache. Each term is reported with a frequency of 20.0%.
The percentage attached to a term should be understood as a registry-reported frequency, not as a comparison between treatments or as evidence about causation. The record does not say whether each event was considered related to the regimen, how serious events were graded, when they occurred, or whether a participant could contribute more than one event term. The deaths field is null, so a separate death count is not reported. The listed term Death should not be used to infer the number, timing, or cause of deaths.
As a general statistical point, safety counts from a small group are highly sensitive to individual experiences and should not be treated as precise estimates of risk in other populations. The registry record does not provide a comparator or enough detail to estimate relative safety. These entries describe what was recorded in this study group and do not establish a treatment effect.
12. What the Result Does, and Does Not, Mean
The registry record documents a planned phase 2 study of bevacizumab combined with chemotherapy and allogeneic hematopoietic stem cell transplantation for advanced solid tumors. It provides the intended regimen, a primary endpoint definition, the follow-up schedule, enrollment, study status, and descriptive adverse-event counts. It also states that the study objectives were not met and that the primary analysis was not performed.
What the record does not provide is a primary endpoint result. It gives no reported count of participants who remained free of progression or death during the first 100 days following transplantation, and no estimate of uncertainty. As a result, it does not establish whether the endpoint was achieved or how outcomes compared with any alternative. No comparator group is described, so comparative effectiveness cannot be assessed from this design as recorded.
The serious and other adverse-event counts describe events recorded among participants at risk. They do not show whether events were caused by the regimen, and they cannot quantify how safety would differ under another treatment. The listed serious adverse event terms and their reported frequencies should not be interpreted as a complete account of event timing, severity, or attribution; these details are not reported in the registry record.
The termination status is a fact about the study record, but the reason for termination is not reported. It should not be taken as proof that the regimen succeeded or failed. Similarly, the statement that objectives were not met and analysis was not performed means that efficacy conclusions cannot be drawn from a primary analysis in this record; it is not itself an estimate of no effect.
The appropriate conclusion is limited: this registry entry describes a small, uncontrolled study that did not report its primary endpoint analysis. It records safety events but does not support a reliable conclusion about efficacy or comparative safety.
13. Why This Trial Matters Statistically
This study illustrates why a clearly stated endpoint does not by itself constitute an interpretable result. The record defines progression-free survival and gives a follow-up schedule, but it also states that analysis was not performed. Without a reported endpoint count or estimate, readers cannot assess the outcome, its precision, or the extent to which observed data answer the primary question.
It also highlights the difference between describing outcomes and estimating a treatment effect. A single-group study can report what happened among its participants, but it lacks a concurrent comparator for separating treatment-associated outcomes from other influences. The small enrollment of 5 further limits how much precision could reasonably be expected from any descriptive result. These design features are particularly important when readers consider safety counts as well as efficacy endpoints.
The record is also a reminder that status labels and outcome statements need careful interpretation. Terminated is a registry status; the reason for termination is not reported. The statement that study objectives were not met and analysis was not performed describes the availability of results, not the direction or size of a treatment effect. A reader should not translate missing analysis into a finding of no benefit or harm.
Finally, planning calculations and observed results answer different questions. The registry describes sample-size calculations as planning illustrations based on an observed effect and stated assumptions, not as the trial's own design. Such illustrations do not substitute for an endpoint analysis and are not observed power. Statistical interpretation depends on clearly reported methods and results, and those are not present for the primary endpoint in this record.
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 main limitation for interpretation is that the registry record reports no primary endpoint analysis. Although progression-free survival is defined, no endpoint count or estimate is available. There is no reported confidence interval, test result, or description of the endpoint data used for analysis. The reason the study objectives were not met and the analysis was not performed is not reported in the registry record.
Enrollment was 5, and the study was single group. The record does not identify a comparator, so outcomes cannot be interpreted as a treatment contrast. With this enrollment, any descriptive event counts are based on a very small group and should not be treated as precise estimates for a broader population. The record also does not report participant characteristics, eligibility criteria in detail, or the distribution of enrolled participants across the listed conditions.
Important endpoint methods are not reported, including rules for censoring, analysis populations, handling of missing follow-up, and the intended statistical model. The outcome timeframe is 100 days after transplant, while participants were to be followed every 3 months for the first year; the record does not explain how the longer follow-up schedule relates to the primary endpoint analysis.
For safety, the record gives affected counts and serious adverse event terms, but not event timing, severity grades, attribution, or participant-level detail. A separate deaths count is null. The reason for study termination is not reported. These gaps limit conclusions about both the outcomes and the conduct of the study; they should not be filled by assuming details that are absent from the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Allogeneic Hematopoietic Stem Cell Transplantation With Bevacizumab for Advanced Solid Tumor — NCT00523809.
- Registry record last updated 2013-01-28; status last verified 2012-12.
- Results first posted 2013-01-28.
- 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 phase 2, single-group study sponsored by M.D. Anderson Cancer Center, with enrollment of 5. It lists breast cancer and ovarian cancer and describes a regimen combining bevacizumab, fludarabine, melphalan, thymoglobulin, and allogeneic hematopoietic stem cell transplantation. The study began in 2007-08, had a primary completion date of 2011-10, and is listed as terminated.
The primary endpoint was progression-free survival, defined as no progression or death from any cause during the first 100 days following transplantation. The record states that study objectives were not met and the analysis was not performed. Serious adverse events were recorded for 4 of 5 participants at risk; other adverse events were recorded for 5 of 5. No comparator or primary efficacy estimate is reported. The reason for termination, analysis methods, endpoint results, and separate deaths count are not reported in the registry record.