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 High-dose Cytarabine/Mitoxantrone Followed by Autotransplantation for t-MDS/t-AML (NCT00774046), a na phase 2 study. The primary outcome is Response to Induction Chemotherapy (CR or PR).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00774046 |
| Phase | Phase 2 |
| Condition | Myelodysplastic Syndrome, Acute Myeloid Leukemia |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 32 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Chicago |
| Results posted | Yes |
2. Clinical Question
Population
The registry record identifies myelodysplastic syndrome and acute myeloid leukemia as the conditions studied. The trial title specifies therapy-related myelodysplastic syndrome or therapy-related acute myeloid leukemia. The recorded enrollment was 32. Further eligibility details and a more specific description of the analyzed population are not reported in the registry record.
Intervention
The study evaluated induction chemotherapy followed by stem cell mobilization and autologous transplantation. The listed drugs are Ara-C, mitoxantrone, and etoposide. The arm description identifies induction chemotherapy followed by stem cell transplant; details such as drug doses and the precise schedule are not reported in the registry record.
Comparator
No separate comparator group is described. The study is recorded as single-group, with allocation listed as NA and masking listed as none. The registry record therefore does not present a randomized comparison or a like-for-like control group.
Primary question
The primary endpoint asks what percentage of participants had a complete or partial response to induction chemotherapy, assessed at Day 28-40. The endpoint description defines complete remission and partial remission and also describes resistant disease and cases not evaluable for response. The registry record does not report the observed response percentage or its confidence interval, so the primary question cannot be answered from the posted results.
3. Trial Design
This is a completed phase 2, single-group trial sponsored by the University of Chicago. Enrollment was 32. The registry lists the study start as 2002-12 and primary completion as 2011-03. Allocation is recorded as NA, masking as none, and the model as single group. These design details describe a study without a separate randomized control arm; they do not support a direct estimate of how outcomes would differ under another treatment.
The arm is described as induction chemotherapy followed by stem cell transplant. The listed interventions are Ara-C, mitoxantrone, and etoposide, with stem cell mobilization and autologous transplant also included in the arm description. The brief summary states that the purpose was to determine the effectiveness of a particular combination of drugs used to treat cancer. Dosing, treatment schedules, eligibility criteria, and protocol-specific decision rules are not reported in the registry record.
The primary outcome is response to induction chemotherapy, defined as complete or partial remission, with assessment at Day 28-40. The registry lists seven outcome measures. Secondary outcomes include feasibility of stem cell collection, numbers of stem cells collected, overall survival among patients undergoing autologous stem cell transplant, and disease-free survival among those patients. The outcome list alone does not establish which participants contributed to each measure or how each measure was analyzed.
The registry record lists zero analyses. It does not report the primary response estimate, a confidence interval, or analysis details. The study status is completed, but completion status does not itself provide evidence about the measured outcomes. Statistical comparisons between treatment groups are not available because no comparator group is described.
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.
Screening
| Stage | Induction Chemotherapy Followed by Stem Cell Transplant |
|---|---|
| STARTED | 116 |
| COMPLETED | 60 |
| NOT COMPLETED | 56 |
Reasons for not completing this period:
| Reason | Induction Chemotherapy Followed by Stem Cell Transplant |
|---|---|
| Not eligible | 56 |
Enrollment
| Stage | Induction Chemotherapy Followed by Stem Cell Transplant |
|---|---|
| STARTED | 60 |
| COMPLETED | 32 |
| NOT COMPLETED | 28 |
Reasons for not completing this period:
| Reason | Induction Chemotherapy Followed by Stem Cell Transplant |
|---|---|
| Desired other therapy/refused | 28 |
Induction Therapy
| Stage | Induction Chemotherapy Followed by Stem Cell Transplant |
|---|---|
| STARTED | 32 |
| COMPLETED | 32 |
| NOT COMPLETED | 0 |
Stem Cell Mobilization
| Stage | Induction Chemotherapy Followed by Stem Cell Transplant |
|---|---|
| STARTED | 10 |
| COMPLETED | 7 |
| NOT COMPLETED | 3 |
Reasons for not completing this period:
| Reason | Induction Chemotherapy Followed by Stem Cell Transplant |
|---|---|
| Count too low (2), sudden death (1) | 3 |
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 | All Patients |
|---|---|---|
| Participants analysed | 32 | |
| Age, Continuous | years | 56 (23 to 83) |
| Sex: Female, Male: Female | Participants | 18 |
| Sex: Female, Male: Male | Participants | 14 |
| Region of Enrollment: United States | participants | 32 |
6. Primary Endpoint
The registry lists the primary outcome as Response to Induction Chemotherapy (CR or PR), measured over Day 28-40.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | 95% Confidence Interval |
| Unit | percentage of participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the percentage of participants with a complete or partial response to induction chemotherapy, assessed at Day 28-40. A response endpoint reduces each participant’s assessment to a category: complete response or partial response counts as a response, while the endpoint title does not include resistant disease or cases that are not evaluable as responses.
The registry defines complete remission as <5% bone marrow blasts with recovery of peripheral blood counts, together with complete cytogenetic remission—the disappearance of any pre-existing cytogenetic abnormality. Partial remission is defined as >5% bone marrow blasts but less than the pre-treatment blast percentage within the bone marrow. Resistant disease is described as no significant cytoreduction in bone marrow leukemic cells from pre-treatment levels. Not evaluable includes patients who died during induction chemotherapy or withdrew from follow-up before assessment could be made.
In general, a response endpoint can describe an early measure of disease status after treatment. The percentage gives the proportion meeting the stated response definition; a confidence interval conveys uncertainty around that estimate. The registry identifies a 95% confidence interval as the dispersion measure, but the response percentage and interval are not reported in the registry record. Thus, the endpoint’s definition is available, but its observed result and precision are not.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record defines a clinically interpretable primary endpoint: response to induction chemotherapy, combining complete and partial remission, at Day 28-40. It also provides definitions for complete remission, partial remission, resistant disease, and not evaluable. However, it does not report the number or percentage of participants who achieved a response, nor the stated 95% confidence interval. Consequently, the principal efficacy result cannot be quantified from the posted results.
The record lists 32 participants enrolled, but enrollment is not necessarily the denominator used for every outcome. The number assessed for response, how participants with no assessment were handled in the analysis, and the analysis population are not reported in the registry record. The definition of not evaluable explicitly includes participants who died during induction chemotherapy or withdrew before assessment, but the record does not state how many, if any, fell into that category.
The trial’s single-group structure is important to interpretation. A response proportion in one group can describe what was observed among participants treated in that study, but without a control group it cannot establish how the outcome compares with another treatment or with an untreated counterfactual. The registry record also does not report analyses that adjust for participant characteristics or other potential sources of variation.
Safety information is reported for all patients: 7 of 32 are listed as affected in the serious adverse event category, and 31 of 32 in the other adverse event category. The listed serious adverse event terms include infection with grade 4 neutrophils, neutropenic fever, hemorrhage, and sudden death, with percentages attached to those terms. These figures describe recorded event categories; they do not provide a treatment comparison or establish that an event was caused by treatment. The deaths field is not reported in the registry record.
The record includes seven outcome measures and zero analyses. It does not report statistical tests, adjusted estimates, or a multiplicity procedure. Any planning illustration based on a fraction of an observed effect is not a trial result or the trial’s own design justification. Since the primary observed effect is not reported in the registry record, such an illustration cannot substitute for the missing response estimate. The available information supports a description of the design, endpoint definitions, and recorded adverse event counts, but not a conclusion about the magnitude or comparative effect of treatment.
9. Statistical Methods Explained
The registry identifies the primary outcome as a percentage of participants and specifies a 95% confidence interval. In general, a binary endpoint classifies each participant into one of two outcome states for the analysis—for this endpoint, response or no recorded response under the stated definition. A percentage expresses the share classified as having the event of interest. Interpreting it requires knowing both the numerator and the denominator, including how participants without an assessment are handled. The record supplies the endpoint definition but does not report the response count, percentage, or analysis denominator.
What does a confidence interval convey?
In general, a confidence interval describes the statistical uncertainty around an estimate. A narrower interval indicates greater precision under the assumptions used to construct it; a wider interval indicates less precision. It does not guarantee that the estimate is free of bias, and it does not represent a range containing every individual participant’s outcome. Here, the registry specifies a 95% confidence interval as the dispersion measure for the primary endpoint, but does not post its limits. The interval’s width and the precision of the response estimate therefore cannot be assessed.
What can a single-group estimate establish?
In general, a single-group study can estimate an outcome frequency among the participants included in its analysis. It cannot by itself separate treatment effects from other explanations for the observed outcome, because there is no concurrent control group to anchor a comparison. This trial is recorded as single-group, with allocation listed as NA and masking as none. Its registry record does not describe a randomized treatment comparison. Accordingly, a hypothetical comparison with another treatment cannot be inferred from the recorded design.
Why do outcome definitions and denominators matter?
A prespecified category definition determines which participant outcomes count as events. The registry’s response definition distinguishes complete remission, partial remission, resistant disease, and not evaluable. The last category includes patients who died during induction chemotherapy or withdrew before an assessment could be made. In general, different approaches to missing or unevaluable outcomes can lead to different estimates. The record does not state the actual number of participants in each response category, how unevaluable cases were treated in the primary analysis, or whether a particular analysis population was used.
The listed secondary outcomes address other aspects of the study, including stem cell collection and survival among participants undergoing autologous transplant. In general, a survival endpoint requires a defined time origin, follow-up period, and method for handling participants whose event status is not known at the end of observation. Those analytic details and results are not reported in the registry record. The outcome names alone are not enough to reconstruct a survival analysis.
How should planning illustrations be read?
In general, sample-size calculations estimate how many participants a future study might need under specified assumptions. They are planning tools, not observed outcomes and not evidence that a completed study had a particular probability of detecting an effect. The described planning illustration assumes a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of the observed effect. For time-to-event outcomes, the description specifies a total event count; for other outcomes, it specifies participants per arm. These are illustration assumptions, not the recorded design of this single-group trial.
The registry record does not report the trial’s sample-size justification, the assumptions used in its original design, or interim analyses. Nor does it report the observed primary effect needed to interpret a calculation based on a fraction of that effect. Such a planning illustration should not be read as observed power, as a trial result, or as evidence that the study was designed around those assumptions.
What do the absence of analyses and results imply?
The registry lists zero analyses. In general, a posted outcome definition without an analysis result does not permit assessment of an estimate, its precision, or a test of a hypothesis. Statistical methods such as adjustment for covariates, alternative model specifications, and sensitivity analyses cannot be assumed when they are not described. For this record, those methods and any inferential results are not reported in the registry record. The appropriate statistical interpretation is limited to the study structure, outcome definitions, and event counts that are actually recorded.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists seven outcome measures, including the primary response endpoint and secondary measures concerning stem cell collection and survival. When a study assesses multiple outcomes, general statistical practice recognizes that the chance of at least one apparently notable finding can increase if many tests are conducted. Some studies address this issue through a prespecified hierarchy or an adjustment procedure. Whether this trial used such an approach is not reported in the registry record.
The registry lists zero analyses and does not report test results or a multiplicity procedure. It is therefore not possible to determine whether any formal adjustment was planned or applied, or how the primary endpoint was prioritized in analysis beyond its designation as primary.
The endpoint definition includes a not-evaluable category for patients who died during induction chemotherapy or withdrew before assessment. The number of such participants, the response-analysis denominator, and the treatment of missing or unevaluable assessments in the analysis are not reported in the registry record. The record also does not specify an analysis population, such as whether all enrolled participants or only participants with an assessment were included. These gaps limit interpretation of the primary response endpoint because the reported percentage depends on who is counted and how unevaluable outcomes are handled.
Details of missing follow-up for the secondary survival outcomes are also not reported in the registry record. No assumptions or sensitivity analyses for missing data are described. Missingness should not be treated as proof of either response or nonresponse without an explicit analysis rule.
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 |
|---|---|---|---|
| All Patients | 7 | 32 | 21.9% |
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 |
|---|---|
| All Patients | 31 of 32 |
Most frequent serious adverse event terms
| Event term | Organ system | All Patients |
|---|---|---|
| Infection with grade 4 neutrophils | Infections and infestations | 3 of 32 |
| Neutropenic fever | Infections and infestations | 1 of 32 |
| Hemorrhage | General disorders | 1 of 32 |
| Sudden death | General disorders | 1 of 32 |
| Hemorrhage | Gastrointestinal disorders | 1 of 32 |
Most frequent non-serious adverse event terms
| Event term | Organ system | All Patients |
|---|---|---|
| Neutropenic fever | Infections and infestations | 19 of 32 |
| Infection/sepsis | Infections and infestations | 16 of 32 |
| Rash | Skin and subcutaneous tissue disorders | 10 of 32 |
| Thrombocytopenia | Blood and lymphatic system disorders | 8 of 32 |
| Non-infectious diarrhea | Gastrointestinal disorders | 8 of 32 |
| Left ventrcular dysfunction | Cardiac disorders | 4 of 32 |
| Hypotension | Cardiac disorders | 4 of 32 |
| Anemia | General disorders | 3 of 32 |
| Pneumonia | Respiratory, thoracic and mediastinal disorders | 3 of 32 |
| Respiratory failure | Respiratory, thoracic and mediastinal disorders | 2 of 32 |
Serious events with the highest arm-level rate: infection with grade 4 neutrophils (9.4%), neutropenic fever (3.1%), hemorrhage (3.1%), sudden death (3.1%).
For all patients, the registry records 32 at risk and 7 affected in the serious adverse event category. It records 32 at risk and 31 affected in the other adverse event category. These are separate categories, and the figures should not be added together; the record does not indicate whether participants with events in one category also had events in the other.
The listed serious adverse event terms and percentages are infection with grade 4 neutrophils, 9.4%; neutropenic fever, 3.1%; hemorrhage, 3.1%; and sudden death, 3.1%. These term-specific percentages are reported as registry entries; the record does not provide further event-level detail or clarify overlap among terms. The deaths field is not reported in the registry record, so a total death count cannot be stated from that field.
In general, adverse event counts describe events recorded during the study and do not by themselves establish that treatment caused an event. The adverse event timeframe, attribution method, and detailed definitions are not reported in the registry record. These figures should therefore be read as descriptive safety information, not as comparative estimates against another treatment or group.
12. What the Result Does, and Does Not, Mean
The registry record documents a completed phase 2, single-group study with enrollment of 32 and an induction-response endpoint assessed at Day 28-40. It defines complete and partial remission and identifies a 95% confidence interval as the measure of dispersion. Those details make clear what the primary endpoint was intended to measure. They do not reveal the observed response result: the percentage and confidence interval are not reported in the registry record.
Without the primary outcome estimate, the magnitude and precision of the observed response cannot be assessed. Without a comparator group, even a reported response proportion would describe the study group rather than establish a treatment difference. The available design information does not support a causal comparison with another treatment, and the registry record does not report an adjusted or comparative analysis.
The safety entries show recorded adverse event counts and term-specific percentages, but they do not establish causation or permit a comparison with another group. The total deaths field is not reported in the registry record. The secondary outcome names show that the record includes measures related to stem cell collection and survival, but their results and analytic details are not reported.
These limits should be distinguished from evidence that an outcome did not occur. A result that is absent from the registry record is not evidence of a zero response, no adverse events, or no deaths. It means the relevant result cannot be established from the posted information. The record supports a description of the planned clinical question, the single-group design, endpoint definitions, enrollment, and recorded safety figures; it does not support a conclusion about the size or comparative effectiveness of the treatment regimen.
13. Why This Trial Matters Statistically
This trial illustrates why the distinction between an endpoint definition and an endpoint result matters. The registry describes a specific response measure, assessment window, remission criteria, and confidence-interval approach. Yet it does not report the primary estimate or interval. A precise endpoint definition makes an analysis interpretable when results are available, but cannot substitute for the results themselves.
The single-group design is another important statistical feature. It can describe outcomes within the treated group, but it does not provide a concurrent basis for estimating a treatment contrast. This distinction prevents a descriptive response rate from being mistaken for evidence of superiority or for a causal effect. It is particularly relevant when a registry’s brief summary uses the general language of determining effectiveness while the recorded design has no comparator group.
The record also demonstrates how safety counts need context. Counts and percentages communicate the frequency of recorded events, but without event-level detail, timing, attribution, and a comparison group they cannot establish what caused an event or how risk differs across treatments. The listed serious adverse event terms should be interpreted descriptively.
Finally, a planning calculation is conceptually separate from an observed analysis. The described assumptions concern a two-arm illustration, while this trial is recorded as single-group. Such an illustration may help explain planning concepts, but it is not the trial’s design rationale, an observed result, or observed power. Keeping these distinctions clear helps readers avoid treating missing results or planning assumptions as evidence about the trial’s outcomes.
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 consequential limitation of the registry record for statistical interpretation is that it does not report the primary response estimate or its 95% confidence interval. Although the endpoint definitions and assessment window are recorded, the response count, analysis denominator, and handling of unevaluable cases are not. The listed not-evaluable definition makes those details particularly relevant, but the number of participants in that category is not reported in the registry record.
The study is recorded as single-group, with no comparator described. Its outcomes therefore cannot be used as a direct randomized comparison with another treatment. The record also lists zero analyses, so statistical tests, adjusted estimates, sensitivity analyses, and the analysis population are not reported in the registry record.
Although seven outcome measures are listed, the record does not describe whether multiplicity was considered. Secondary outcome results and the analytic details for survival measures are not reported in the registry record. The deaths field is also not reported. The safety entries lack the detailed event timing and attribution information needed to determine whether events were considered treatment-related or to compare event rates with another group.
Protocol details such as eligibility criteria, treatment doses and schedules, and the original sample-size justification are not reported in the registry record. The described sample-size illustration uses assumptions for a two-arm calculation and is not the recorded trial design. These omissions constrain both reproducibility and the strength of conclusions that can be drawn from the posted information.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: High-dose Cytarabine/Mitoxantrone Followed by Autotransplantation for t-MDS/t-AML — NCT00774046.
- Registry record last updated 2014-02-11; status last verified 2014-01.
- Results first posted 2013-06-24.
- 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 record describes a completed phase 2, single-group trial sponsored by the University of Chicago, with enrollment of 32. The study evaluated induction chemotherapy using Ara-C, mitoxantrone, and etoposide, followed by stem cell mobilization and autologous transplantation. The primary endpoint was response to induction chemotherapy at Day 28-40, defined as complete or partial remission.
The record lists seven outcome measures and zero analyses. It does not report the primary response percentage or its 95% confidence interval. For all patients, it records 7 of 32 affected in the serious adverse event category and 31 of 32 in the other adverse event category. The record supports description of the design, endpoint definitions, and listed safety figures, but not a conclusion about comparative treatment effects.