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 Clofarabine, Cytarabine, and Filgrastim in Treating Patients With Newly Diagnosed Acute Myeloid Leukemia, Advanced Myelodysplastic Syndrome, and/or Advanced Myeloproliferative Neoplasm (NCT01101880), a na phase 2 study. The primary outcome is Rates of Complete Remission and Complete Remission With Incomplete Recovery of Counts.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01101880 |
| Phase | Phase 2 |
| Condition | Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities, Adult Acute Myeloid Leukemia With Del(5q), Adult Acute Myeloid Leukemia With Inv(16)(p13;q22) |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 50 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Washington |
| Results posted | Yes |
2. Clinical Question
Population
Adults younger than 65 with newly diagnosed acute myeloid leukemia (AML), advanced myelodysplastic syndrome (MDS), and/or advanced myeloproliferative neoplasm. The listed conditions include AML with specified cytogenetic abnormalities, chronic myelomonocytic leukemia, de novo MDS, refractory anemia with excess blasts, untreated AML, and myeloproliferative neoplasm with 10% blasts or higher.
Intervention
The treatment combines filgrastim, clofarabine, and cytarabine. During induction, filgrastim begins the day before chemotherapy and continues until blood counts recover. Clofarabine is followed by cytarabine daily for 5 days. The registry also describes consolidation therapy with filgrastim, but its description does not give a complete consolidation regimen.
Comparator
There is no separate comparator group. The registry describes a single-group study, with no allocation to different treatment arms. Outcomes therefore describe the enrolled group receiving the treatment; they do not constitute a randomized comparison against another treatment or a control group.
Primary question
The primary endpoint concerns the rates of complete remission (CR) and complete remission with incomplete recovery of counts (CRi), assessed up to 5 years. The registry record does not report the observed remission counts or rates, so it does not provide an estimate of how often either endpoint occurred.
3. Trial Design
This is a Phase 2, open-label, single-group study sponsored by the University of Washington. The registry lists an enrollment of 50 and a completed status. It describes adults younger than 65 with newly diagnosed AML or advanced MDS and/or advanced myeloproliferative neoplasm. The eligibility conditions include several AML cytogenetic categories and other specified myeloid disorders. The record does not give a separate control group or a randomized allocation process.
The treatment is a combination of filgrastim, clofarabine, and cytarabine. For induction, filgrastim is given daily beginning the day before chemotherapy and continuing until blood counts recover. Clofarabine is administered intravenously over 1 hour, followed by cytarabine intravenously over 2 hours, daily for 5 days. The registry describes filgrastim during consolidation, but the posted arm description does not fully specify that phase. Drug doses and additional regimen details are not reported in the registry record.
The primary outcome is the rate of CR and CRi, with a timeframe of up to 5 years. The record defines the remission categories by bone marrow blasts and blood-count recovery. It states that the estimate's standard error was expected to be 5 to 7 percentage points with 50 patients, depending on the observed rate. This is a planning statement in the outcome description, not a reported precision estimate for an observed result.
The registry lists six outcome measures, but no analysis entries. It does not report the observed primary outcome counts or rates, an analysis population, or a detailed statistical analysis plan. The study's completed status does not by itself establish that the registry contains posted results for every outcome.
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 | Treatment (Chemotherapy and Colony Stimulating Factor) |
|---|---|
| STARTED | 50 |
| COMPLETED | 50 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: CR achieved with no AHD only applies to those who did not have AHD.
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 | Treatment (Chemotherapy and Colony Stimulating Factor) |
|---|---|---|
| Participants analysed | 50 | |
| Age, Continuous | years | 53 (22 to 64) |
| Sex: Female, Male: Female | Participants | 23 |
| Sex: Female, Male: Male | Participants | 27 |
| Cytogenetic Risk Factor: Favorable | Participants | 4 |
| Cytogenetic Risk Factor: Intermediate | Participants | 32 |
| Cytogenetic Risk Factor: Unfavorable | Participants | 13 |
| Cytogenetic Risk Factor: Indeterminate | Participants | 1 |
| Antecedent hematological disorder (AHD) | Participants | 23 |
| FLT3 ITD mutation status | Participants | 10 |
| WBC | cells x 10^9/L | 12 (0.8 to 761.3) |
| Peripheral Blast | percent of white blood cells | 16 (0 to 100) |
6. Primary Endpoint
The registry lists the primary outcome as Rates of Complete Remission and Complete Remission With Incomplete Recovery of Counts, measured over Up to 5 years.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary outcome combines two remission categories: complete remission and complete remission with incomplete recovery of counts. CR requires less than 5% blast cells in the bone marrow together with count recovery, defined as an absolute neutrophil count greater than 1000/microL and a platelet count greater than 100,000/microL. CRi also requires less than 5% bone marrow blasts, but without complete count recovery; the description specifies an absolute neutrophil count less than 1000/microL and a platelet count less than 100,000/microL.
These categories distinguish a marrow response from the degree of blood-count recovery. Reporting them together can describe remission outcomes that would be obscured if only full count recovery were considered. The registry also identifies a CR endpoint that applies only to participants who did not have AHD; the meaning and analysis details for that population are not fully reported in the record.
The stated timeframe is up to 5 years. The record describes estimating rates and gives an expected standard error range, but does not post the number of participants meeting either remission definition or the resulting rates. It therefore does not permit assessment of the observed endpoint values or their precision.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies a single treatment group and remission as the primary outcome. Its outcome description explains how CR and CRi are defined and states an anticipated standard error range for the rate estimates. It does not report the observed number of participants meeting either definition, the corresponding rates, or confidence intervals. Consequently, the remission results cannot be interpreted quantitatively from the registry record.
The anticipated standard error of 5 to 7 percentage points is a statement about planned estimation precision with 50 patients, conditional on the observed rate. It is not an observed standard error, confidence interval, treatment effect, or statistical test result. The record does not report a specific estimate to which that precision statement can be applied.
Because the study is single-group and has no comparator, any posted outcome rate would describe the enrolled group under the study treatment. It would not, on its own, establish how outcomes compare with another treatment or what would have occurred without this regimen. Differences in participant characteristics, disease categories, and other aspects of care cannot be separated from treatment effects by a single-group design.
The completed status and enrollment entry indicate that the registry record describes a completed study with an enrollment of 50. However, the record has no analysis entries and no posted primary outcome estimate. Completion is not a substitute for outcome reporting, and enrollment is not evidence that every enrolled participant was included in each endpoint analysis.
The adverse-event information is also limited. The safety group records 50 participants at risk and 50 affected, while listing serious-event terms with percentages. The record does not supply further detail about the event definitions, observation period, participant-level overlap among terms, or analysis method. These figures should therefore be read as registry safety entries, not as a complete account of event timing, severity patterns, or causal attribution.
Planning illustrations based on a stated two-arm, equal-allocation framework are not a description of this single-group trial's design. Their assumptions do not create a randomized comparator, and they should not be read as observed power or as evidence of an observed treatment effect.
9. Statistical Methods Explained
What does a single-group study estimate?
In general, a single-group study can describe outcomes among the participants who receive the study regimen. For a binary endpoint such as CR or CRi, the basic descriptive quantity is the proportion of participants meeting the endpoint in the analysis population. The registry record does not report the observed counts, rates, or analysis population for these outcomes, so no such estimate can be interpreted from this record.
A single-group rate is not the same as a comparative treatment effect. Without a concurrent comparator, there is no direct estimate of the difference between treatment strategies. Comparisons with outcomes from other studies would require additional assumptions about how populations, eligibility, outcome definitions, follow-up, and care differed. Those comparisons are not reported in the registry record.
What does the stated standard error describe?
In general, a standard error describes the sampling variability of an estimate: how much an estimate might vary across repeated samples under a statistical model. The registry's primary outcome description says that with 50 patients, the rates would have an estimated standard error of 5 to 7 percentage points, depending on the observed rates. This is an anticipated precision statement. It is not a result calculated from posted remission data, because the record does not provide those data.
A confidence interval uses an estimate and its standard error, together with a specified confidence procedure, to express uncertainty about a parameter. No primary endpoint confidence interval or interval method is reported in the registry record. A confidence interval should not be reconstructed without the observed outcome count and an appropriate method; neither is available in this record.
Why do remission definitions matter?
CR and CRi share a marrow blast requirement but differ in count recovery. Separating these categories preserves information about participants who meet the marrow criterion but not the specified blood-count thresholds for complete recovery. Combining categories, reporting them separately, or defining a population-specific endpoint can lead to different summaries. The record names CR and CRi and includes a population qualification for CR achieved with no AHD, but it does not explain how that qualification was handled in the analysis.
In general, endpoint definitions should be applied consistently, and the analysis should state which participants are eligible for each endpoint. Missing follow-up assessments or incomplete laboratory information can affect whether endpoint status is established. The registry does not report how missing or unevaluable endpoint information was handled.
What do the planning illustrations mean?
In general, a sample-size calculation describes how many participants a hypothetical design might require under stated assumptions. Such a calculation is not the same as observed power, which is not an appropriate substitute for interpreting an estimate and its uncertainty after a study. The planning assumptions associated with illustrations in the record specify a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; they also describe detecting a stated fraction of an observed effect. Time-to-event calculations are described as using total events, while other calculations are expressed per arm.
Those assumptions describe a two-arm planning framework, whereas this trial is registered as a single-group study. The illustrations therefore do not establish the trial's own design or analysis plan. They are not evidence that the study had a particular power, nor do they provide an observed comparison. The trial's own sample-size justification and statistical plan are not reported in the registry record.
How should the safety percentages be understood?
In general, adverse-event summaries depend on the event definitions, follow-up period, and denominator. The registry records a safety group with 50 participants at risk and 50 affected and lists serious-event terms with percentages. It does not explain whether terms represent participants, event occurrences, or another summary basis, nor whether an individual could contribute to multiple terms. These details limit interpretation of the percentages. The number of deaths is not reported in the registry record; an absent value should not be interpreted as zero.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists six outcome measures, but the posted record does not describe a complete statistical analysis plan or identify a multiplicity-control strategy. Multiplicity arises in general when several outcomes, time points, subgroups, or statistical tests are considered: the chance of at least one apparently unusual result can increase as the number of analyses grows. Whether and how that issue was addressed in this study is not reported in the registry record.
The primary outcome names CR and CRi, and the description also refers to a CR population that applies only to participants who did not have AHD. The record does not explain whether the remission categories were analyzed separately or jointly, which endpoint had priority in inference, or how the population-specific endpoint was treated. No adjustment method or hierarchy of outcomes is reported.
Missing-data handling is not reported in the registry record. In general, an endpoint may be unavailable if a participant lacks the required assessment or if count recovery cannot be determined. Excluding such cases, treating them as non-events, or using another approach can change an estimated rate. The record does not state which approach was used, how many participants had missing endpoint information, or whether follow-up was complete.
The analysis populations are also not described. The registry does not say whether the primary analysis included all enrolled participants, only participants who began treatment, or another defined population. It does not report exclusions, deviations, or endpoint-specific denominators. These omissions prevent a clear assessment of how the reported enrollment relates to any analysis set; no observed analysis estimates are posted in the 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 |
|---|---|---|---|
| Treatment (Chemotherapy and Colony Stimulating Factor) | 50 | 50 | 100.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Treatment (Chemotherapy and Colony Stimulating Factor) | 0 of 0 |
Most frequent serious adverse event terms
| Event term | Organ system | Treatment (Chemotherapy and Colony Stimulating Factor) |
|---|---|---|
| infection | Infections and infestations | 50 of 50 |
| Pulmonary | Respiratory, thoracic and mediastinal disorders | 31 of 50 |
| Liver enzymes | Hepatobiliary disorders | 20 of 50 |
| Gastrointestinal | Gastrointestinal disorders | 10 of 50 |
| Metabolic | Metabolism and nutrition disorders | 10 of 50 |
| Dermatologic | Skin and subcutaneous tissue disorders | 10 of 50 |
| Neurologic | Nervous system disorders | 6 of 50 |
| Coagulation | Blood and lymphatic system disorders | 4 of 50 |
| Cardiovascular | Cardiac disorders | 2 of 50 |
| Ocular | Eye disorders | 1 of 50 |
Serious events with the highest arm-level rate: infection (100.0%), pulmonary (62.0%), liver enzymes (40.0%), gastrointestinal (20.0%), metabolic (20.0%).
The registry's safety group records 50 participants at risk and 50 affected. It lists infection at 100.0%, Pulmonary at 62.0%, Liver enzymes at 40.0%, Gastrointestinal at 20.0%, Metabolic at 20.0%, and Dermatologic at 20.0% among the serious-event terms. These are registry entries; the record does not provide further detail on the denominator or whether the percentages refer to participants or event occurrences. It also does not explain whether participants could appear under more than one term.
The listed terms do not describe timing, duration, severity grades, recurrence, or the relationship of an event to treatment. The safety reporting period and detailed serious-event definitions are not reported in the registry record. The death count is not reported, so it should not be interpreted as no deaths. These entries are limited summaries and do not provide a complete account of safety outcomes or establish that treatment caused an event.
12. What the Result Does, and Does Not, Mean
The registry record describes a Phase 2, single-group treatment study and defines remission outcomes using bone marrow blasts and blood-count recovery. It also gives an anticipated standard error range for estimating remission rates with 50 patients. These details explain the outcome being studied and the intended level of estimation precision, but they do not supply the observed remission results.
The record does not report the number meeting CR or CRi, their rates, confidence intervals, or an analysis population. It therefore does not support a numerical conclusion about the frequency of remission in this study. The completed status and stated enrollment do not fill that reporting gap.
Even if a single-group outcome rate were posted, it would describe what was observed in the enrolled group. Without a control group, the study cannot directly distinguish the effect of the regimen from other influences, including participant characteristics, disease mix, or other aspects of care. It would not be a randomized comparison or a direct estimate of superiority over another approach.
The safety entries likewise have interpretive limits. The registry lists the number at risk and affected, along with serious-event terms, but does not clarify all denominators, event-level details, or causal attribution. The unreported death count cannot be treated as zero. The posted safety summary should not be taken as a complete description of all harms.
In general, clinical decisions require consideration of evidence beyond an incomplete registry summary. This statistical description is limited to what the registry reports and does not offer medical advice or establish whether the treatment should be used.
13. Why This Trial Matters Statistically
This study illustrates the distinction between describing an outcome and estimating a comparative treatment effect. The primary endpoint is a remission rate in a single treatment group. A rate can be clinically and statistically informative as a description of that group, but it cannot by itself show how outcomes differ from a comparator that was not included.
The endpoint also illustrates why definitions matter. CR requires both a marrow response and specified count recovery, whereas CRi allows incomplete count recovery while retaining the marrow blast criterion. Reporting these categories can preserve distinctions that a single undifferentiated response label would conceal. The registry's additional reference to a population-specific CR endpoint makes clarity about eligibility and analysis populations particularly important.
The outcome description explicitly connects enrollment and anticipated precision: it states that rates with 50 patients would have a standard error of 5 to 7 percentage points, depending on the observed rates. This is a useful reminder that a planned estimate can have uncertainty even when the sample size is fixed. It is not a substitute for reporting the actual rates, their uncertainty, and the participants contributing to each analysis.
Finally, the record demonstrates why completion status and outcome reporting must be distinguished. The registry says the study is completed, but it does not post primary outcome estimates or analysis entries. Without those results and details about missing data, multiplicity, and analysis populations, readers cannot evaluate the remission findings statistically. Transparency about those elements is essential for judging what a clinical study can and cannot establish.
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 registry record does not report observed CR or CRi counts, rates, confidence intervals, or endpoint-specific denominators. Although the study is marked completed and lists an enrollment of 50, those entries do not show how many participants contributed to each outcome analysis. No analysis entries are listed.
The record does not report the statistical analysis plan, sample-size justification, analysis populations, missing-data methods, or multiplicity approach. The outcome description gives an anticipated standard error range, but no observed estimate is available to assess against it. The record also does not state how the AHD-qualified remission endpoint was analyzed.
The study has no comparator group. This limits interpretation to outcomes in the treated group and prevents a direct randomized estimate of differences between treatments. The registry's planning assumptions describe equal allocation between two arms, which does not match the registered single-group design; those assumptions do not document the trial's actual design or analysis.
The treatment description does not report drug doses, and the consolidation description is incomplete. The safety summary gives serious-event terms but does not fully specify denominator interpretation, observation period, event overlap, or the number of deaths. These limitations prevent a detailed assessment of efficacy estimates, analysis precision, treatment comparisons, or the full safety experience from the registry record alone.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Clofarabine, Cytarabine, and Filgrastim in Treating Patients With Newly Diagnosed Acute Myeloid Leukemia, Advanced Myelodysplastic Syndrome, and/or Advanced Myeloproliferative Neoplasm — NCT01101880.
- Registry record last updated 2017-10-19; status last verified 2017-09.
- Results first posted 2017-10-19.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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
NCT01101880 is a completed, open-label Phase 2, single-group study sponsored by the University of Washington. It lists enrollment of 50 and evaluates filgrastim with clofarabine and cytarabine in adults younger than 65 with newly diagnosed AML or advanced MDS and/or advanced myeloproliferative neoplasm.
The primary outcome is the rates of CR and CRi, assessed up to 5 years. The registry defines the remission categories and states an expected standard error range, but does not report observed outcome estimates or analysis entries. It also records a safety group and serious-event terms, with important details of event definitions and denominators not fully described. There is no comparator group, and the record does not report the analysis plan, missing-data methods, or analysis populations.