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 Myeloablative Allogeneic Stem Cell Transplantation Using a Naive T-Cell Depleted Peripheral Blood Stem Cell Graft (NCT00814983), a non-randomized phase 1, phase 2 study. The primary outcome is The Incidence of Grade II-IV Acute Graft Versus Host Disease.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00814983 |
| Phase | Phase 1, Phase 2 |
| Condition | ALL, ANLL, MDS |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 15 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Duke University |
| Results posted | Yes |
2. Clinical Question
Population
The record concerns people with ALL, ANLL, MDS, or NHL undergoing myeloablative allogeneic stem cell transplantation. The registry does not report further eligibility criteria or the characteristics of participants who received a transplant.
Intervention
The experimental approach was a peripheral blood stem cell graft depleted of CD45RA+ naive T-cells. The experimental cohort was described as receiving a T-cell depleted graft, with other aspects of transplantation in line with the standard of care.
Comparator
The comparison cohort was described as receiving a stem cell transplant without graft manipulation, using the currently accepted standard approach to myeloablative allogeneic transplantation. The study was non-randomized, and the experimental arm was not opened.
Primary question
The stated primary endpoint was the incidence of Grade II-IV acute graft-versus-host disease within one year from transplant. No analysis was performed because the experimental arm was not opened, so the registry does not provide a comparative estimate for this question.
The study’s stated primary objectives were to measure safety and efficacy for transplantation using a graft depleted of CD45RA+ naive T-cells. Its secondary objective was to measure the pace of immune recovery. The registry lists rate of immune recovery as a secondary outcome, but does not report an analysis of that outcome.
The clinical question is therefore best understood as a planned evaluation rather than a completed comparison of the two approaches. The record identifies the intended population, transplant procedures, and primary endpoint, but does not show an experimental-arm outcome or a treatment-effect estimate. Enrollment is recorded as 15; the registry does not report how many participants were analyzed for the primary endpoint or provide outcome results by cohort.
3. Trial Design
This was a Phase 1 and Phase 2, parallel, non-randomized study with no masking. The registry identifies Duke University as the sponsor. The listed conditions are ALL, ANLL, MDS, and NHL. The recorded enrollment is 15. The study started in 2007-07, and primary completion is recorded as 2013-09. Its current status is terminated; the reason for termination is not reported in the registry record.
The planned comparison involved a control cohort receiving a stem cell transplant without manipulation and an experimental cohort receiving a T-cell depleted peripheral blood stem cell graft. The control description calls its approach the currently accepted standard for myeloablative allogeneic stem cell transplantation. The experimental description states that other aspects of transplantation would be in line with the standard of care. These descriptions establish the intended contrast, but do not establish that both approaches were administered.
The record explicitly states that the experimental arm was not opened. That matters for interpreting the design: although two cohorts are described, the registry does not present a completed, concurrent comparison of their outcomes. The study is also designated non-randomized, so assignment by chance was not part of the design as recorded. The method by which participants would have been assigned to cohorts is not reported in the registry record.
The intervention list also names an Isolex device from Baxter. The record does not explain how that device was used in relation to the planned graft manipulation, and no additional procedural details should be inferred from its listing. The registry’s primary endpoint was incidence of Grade II-IV acute graft-versus-host disease at one year from transplant. Immune recovery was identified as a secondary objective and rate of immune recovery as a secondary outcome.
In practical terms, the design information describes the intended clinical comparison, while the posted outcome information does not support an estimate of that comparison. Enrollment, study status, and the absence of an opened experimental arm should not be treated as evidence about the relative safety or efficacy of the transplant approaches.
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 | Stem Cell Transplant No Manipulation | Naive T-cell Depleted Stem Cell Transplant |
|---|---|---|
| STARTED | 15 | 0 |
| COMPLETED | 12 | 0 |
| NOT COMPLETED | 3 | 0 |
Reasons for not completing this period:
| Reason | Stem Cell Transplant No Manipulation | Naive T-cell Depleted Stem Cell Transplant |
|---|---|---|
| Screen failure | 1 | 0 |
| Withdrawal by Subject | 1 | 0 |
| Graft failure | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: No analysis was performed since the experimental arm was not opened
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 | Stem Cell Transplant No Manipulation | Naive T-cell Depleted Stem Cell Transplant | Total |
|---|---|---|---|---|
| Participants analysed | 15 | 0 | 15 | |
| Age Categorical: <=18 years | participants | 0 | — | 0 |
| Age Categorical: Between 18 and 65 years | participants | 15 | — | 15 |
| Age Categorical: >=65 years | participants | 0 | — | 0 |
| Gender: Female | participants | 8 | — | 8 |
| Gender: Male | participants | 7 | — | 7 |
| Region of Enrollment: United States | participants | 15 | — | 15 |
6. Primary Endpoint
The registry lists the primary outcome as The Incidence of Grade II-IV Acute Graft Versus Host Disease, measured over One year from date of 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 is the incidence of Grade II-IV acute graft-versus-host disease, assessed one year from the date of transplant. Acute graft-versus-host disease is a complication considered after allogeneic transplantation. The grade range in the endpoint specifies which severity levels count toward the stated outcome; the registry does not provide additional criteria for grading or endpoint adjudication.
Incidence is used to describe how often an event occurs within a defined group and observation period. For a transplant study, tracking this outcome over a stated period can provide a focused measure of a clinically important complication. The one-year timeframe gives the endpoint a defined horizon, but the registry does not say how participants who died, withdrew, or had incomplete follow-up would be handled.
The record says no analysis was performed because the experimental arm was not opened. It gives no event count, incidence estimate, confidence interval, or comparison between cohorts for this endpoint. Accordingly, the stated endpoint identifies what the study intended to measure, but the registry does not establish the incidence of the event in either cohort or the difference between approaches.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical fact is that the primary endpoint was not analyzed. The registry states that the experimental arm was not opened, and explicitly links that circumstance to the absence of an analysis of Grade II-IV acute graft-versus-host disease. Consequently, there is no posted effect estimate, uncertainty interval, or statistical test for the primary question. The record cannot support a conclusion about whether the two planned transplant approaches differed on this endpoint.
The enrollment field records 15, but that total is not an endpoint denominator. The record does not say how many people received a transplant, how many belonged to the control cohort, or how many had follow-up through the one-year timeframe. It would therefore be inappropriate to treat the enrollment total as the analyzed population or use it to infer an event rate. Cohort-specific enrollment and analysis populations are not reported in the registry record.
Non-randomized allocation also limits the interpretation of any comparison that might have been possible. In general, random assignment helps balance known and unknown baseline factors between groups. Without it, differences in participant characteristics, clinical circumstances, or care could be entangled with differences between treatment approaches. In this record, the more fundamental issue is that the experimental arm was not opened, so a comparative endpoint estimate is not reported at all.
The registry’s adverse-event entries list zero for the fields recording participants at risk and affected in each group. Those entries do not supply evidence that no adverse events occurred: the record does not establish an analyzed or exposed population to which those zeros could be applied. Serious-event terms are not listed, and deaths are not reported in the registry record. These fields should not be read as a complete safety analysis.
The study is marked terminated, but the reason for termination is not reported in the registry record. Termination alone does not explain whether the study stopped because of recruitment, feasibility, safety, funding, or another consideration. No such cause can be inferred from the status field.
The registry identifies immune recovery as a secondary objective and rate of immune recovery as a secondary outcome. It does not provide an analysis or results for that outcome. Overall, the posted information describes a planned clinical question and study structure, but reports no analyzed result from which to estimate effects or their precision.
9. Statistical Methods Explained
What does the primary endpoint represent?
The endpoint is the incidence of Grade II-IV acute graft-versus-host disease within one year from transplant. As a general statistical concept, an incidence endpoint counts the occurrence of a defined event over a stated follow-up period. To estimate it, an analysis needs a clear event definition, a population at risk, and sufficient outcome and follow-up information. The registry supplies the endpoint name and timeframe, but it does not report event counts, denominators, follow-up completeness, or an endpoint estimate.
The record does not describe whether the endpoint would be analyzed as a simple proportion, a time-to-event outcome, or by another method. These approaches answer related but not identical questions. A proportion uses the number of people with an event relative to a defined group. A time-to-event analysis also uses information about when events occur and can account for differing follow-up, subject to its assumptions. No particular method should be attributed to this study because the statistical plan is not reported in the registry record.
What can be inferred from the study design?
The study is listed as non-randomized, parallel, and unmasked. In general, a parallel design follows separate groups receiving different approaches. Non-randomized allocation can leave groups different at baseline, which may complicate causal interpretation. Masking can reduce some forms of assessment or management bias, depending on who is masked and how outcomes are measured. Here, masking is listed as none. The registry does not give further detail about allocation procedures, outcome assessment, or measures intended to address bias.
Those general design considerations do not create a result where none is reported. The experimental arm was not opened, and the registry states that the primary outcome was not analyzed. Thus, there is no study-specific estimate to interpret for confounding, precision, or statistical significance. A model or adjustment strategy cannot be described because none is reported in the registry record.
What do confidence intervals and tests usually tell readers?
As a general explanation, a confidence interval expresses the precision of an estimated quantity under a specified statistical method. A narrow interval indicates greater precision than a wide interval, while an interval spanning a broad range of plausible values signals substantial uncertainty. A hypothesis test evaluates data against a specified null hypothesis under its assumptions. Neither an interval nor a test can substitute for a meaningful study estimate, and neither is available for the primary endpoint in this record.
The registry reports zero analyses. It does not report a p-value, confidence interval, adjusted estimate, or unadjusted estimate for the primary endpoint. This is not a result showing no difference; it is the absence of a reported analysis. Likewise, the lack of a statistically significant finding cannot be claimed, because no test result is reported.
How should the planning illustrations be read?
The stated planning assumptions describe illustrations based on an observed effect, using a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. The effect to detect is described as a stated fraction of the observed effect. For time-to-event outcomes, the illustration is based on total events using the Schoenfeld method; other outcomes use participants per arm. These are planning conventions, not evidence that the trial used those assumptions in its original design.
Sample-size illustrations are conditional on the effect size and assumptions used. They do not describe the number of participants actually analyzed, and they are not observed power. Because the primary endpoint was not analyzed and no primary effect estimate is reported, these planning conventions cannot be interpreted as a study-specific demonstration of precision or ability to detect a real difference. The registry does not report the original protocol’s sample-size justification.
Why does over-dispersion matter in general?
For outcomes modeled as counts, over-dispersion means that observed variability exceeds what a simpler model assumes. If it is ignored, standard errors may be too small and uncertainty may be understated. This is a general issue in count-data analysis, not a method reported for this study. The primary endpoint is stated as incidence, and the registry does not describe a count model or any adjustment for over-dispersion.
More broadly, statistical methods depend on how outcomes are defined and observed. Missing follow-up, competing events, repeated measurements, and differences in exposure can affect which analysis is appropriate. The registry does not describe methods for handling these issues. Given the absence of a primary analysis, the most defensible interpretation is limited to what the record states: the intended endpoint and timeframe, the planned design, and the reason the endpoint was not analyzed.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies one primary endpoint: incidence of Grade II-IV acute graft-versus-host disease within one year from transplant. It also names rate of immune recovery as a secondary outcome and describes immune recovery as a secondary objective. The record lists three outcome measures, but does not provide the names or analysis details for all of them in the information.
Multiplicity concerns arise when investigators evaluate multiple outcomes, timepoints, or comparisons. In general, conducting many statistical tests can increase the chance of a false-positive finding unless the analysis plan accounts for that multiplicity. The registry does not report whether any multiplicity adjustment, hierarchy, or prespecified testing strategy was planned. Since no primary analysis was performed and no secondary analysis is reported, there are no reported statistical findings for which the effect of multiplicity can be assessed.
Missing-data methods are not reported in the registry record. The record does not explain how incomplete follow-up, missing outcome assessments, withdrawal, or death would be handled. It also does not define an intention-to-treat, per-protocol, or other analysis population. The enrollment total of 15 cannot stand in for these missing details or establish how many participants contributed outcome data.
The adverse-event entries contain zero values for the listed at-risk and affected fields in both groups, but the record does not establish exposure denominators or provide a safety analysis. Death counts are not reported in the registry record. These omissions prevent a fuller assessment of safety reporting and analysis populations.
11. What the Result Does, and Does Not, Mean
The record establishes that investigators planned to study a graft depleted of CD45RA+ naive T-cells and identified acute graft-versus-host disease within one year as the primary endpoint. It also establishes that the study was non-randomized, that the experimental arm was not opened, and that no analysis of the primary endpoint was performed. Those statements describe the status of the study and its planned question; they do not quantify a treatment effect.
The absence of a reported analysis is not evidence that the approaches had equal outcomes, nor is it evidence that the experimental approach was better or worse. No event rate, between-cohort difference, uncertainty interval, or statistical test is reported. Similarly, the adverse-event fields do not establish that no harms occurred, because the record does not identify a meaningful analyzed or exposed population for those entries.
The study’s secondary objective was immune recovery, but no result for that outcome is reported. The registry also does not state why the study was terminated. Neither the termination status nor the enrollment total explains the missing endpoint analysis or supplies a substitute result.
In general, clinical trial results must be interpreted in light of who was treated, what outcomes were observed, how complete follow-up was, and what analysis was prespecified. Those details are not reported sufficiently to support a comparative conclusion. The record is informative about the intended design and the fact that the planned experimental comparison did not proceed as described, but it does not answer the clinical question with outcome data.
12. Why This Trial Matters Statistically
This record illustrates an important distinction between a trial’s planned question and the evidence it ultimately reports. A registry can identify a target population, intervention, comparator, and endpoint even when the intended comparison does not produce an analysis. Readers need to distinguish those design elements from observed results: a stated endpoint is not itself an endpoint finding.
The non-randomized design is also relevant to statistical interpretation. In general, non-randomized comparisons may be affected by differences between groups that are not caused by the treatment approach. Randomization is one way to reduce that concern, though it does not eliminate every source of uncertainty. In this study, the record’s statement that the experimental arm was not opened means that a comparison is not available to assess, regardless of those general design considerations.
Finally, the listed enrollment and adverse-event fields show why denominators and analysis populations matter. An enrollment total does not reveal how many participants received each intervention or contributed outcome data. Zero entries in adverse-event fields cannot be interpreted as zero risk without knowing who was exposed and how events were collected. Statistical reporting requires both outcome values and clear information about the population behind them.
The record therefore matters as an example of how to read incomplete trial reporting carefully. It documents a planned clinical investigation and a specific reason the primary analysis was not performed, while leaving the intended comparative question unanswered by posted outcome estimates.
13. 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 is explicit: the experimental arm was not opened, and no primary endpoint analysis was performed. There is therefore no comparative estimate for the incidence of Grade II-IV acute graft-versus-host disease. The record cannot establish an event rate for either cohort or the precision of an estimated contrast.
Enrollment is recorded as 15, but participant flow and cohort-specific numbers are not reported in the registry record. The record does not identify how many participants underwent transplantation, how many received an unmanipulated graft, or the number with outcome follow-up. It also does not report eligibility criteria beyond the listed conditions, baseline characteristics, or the handling of withdrawals and missing assessments.
The study is non-randomized and unmasked. The allocation process and any statistical approach for addressing differences between cohorts are not reported in the registry record. In general, these design features can make comparisons vulnerable to bias, although no comparative estimate is available in this case to evaluate.
Further limitations include the absence of reported statistical methods, a sample-size justification, missing-data procedures, and analysis-population definitions. The reason for termination is not reported. The adverse-event entries do not establish exposure denominators, and deaths are not reported in the registry record. These gaps mean that the posted record cannot be used as a complete analysis of safety, efficacy, or immune recovery.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Myeloablative Allogeneic Stem Cell Transplantation Using a Naive T-Cell Depleted Peripheral Blood Stem Cell Graft — NCT00814983.
- Registry record last updated 2013-11-25; status last verified 2013-09.
- Results first posted 2013-11-25.
- 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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17. Record Summary
The registry describes a Phase 1 and Phase 2, parallel, non-randomized, unmasked study of myeloablative allogeneic stem cell transplantation. The planned experimental cohort would receive a peripheral blood stem cell graft depleted of CD45RA+ naive T-cells; the control cohort was described as receiving a transplant without manipulation. The listed conditions are ALL, ANLL, MDS, and NHL.
Enrollment is recorded as 15. The study started in 2007-07, primary completion is recorded as 2013-09, and status is terminated. The primary endpoint was incidence of Grade II-IV acute graft-versus-host disease within one year from transplant. The registry states that no analysis was performed because the experimental arm was not opened. Rate of immune recovery is listed as a secondary outcome, without a reported analysis. The reason for termination and the primary endpoint results are not reported in the registry record.