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 Donor Stem Cell Transplant After Chemotherapy for the Treatment of Recurrent or Refractory High-Risk Solid Tumors in Pediatric and Adolescent-Young Adults (NCT04530487), a na phase 2 study. The primary outcome is Tolerability of Allogeneic HCT.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04530487 |
| Phase | Phase 2 |
| Condition | Desmoplastic Small Round Cell Tumor, Ewing Sarcoma/Peripheral Primitive Neuroectodermal Tumor, Recurrent Desmoplastic Small Round Cell Tumor |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 1 |
| Arms in the primary outcome | n/a |
| Lead sponsor | M.D. Anderson Cancer Center |
| Results posted | Yes |
2. Clinical Question
Population
Pediatric and adolescent-young adult patients with high-risk solid tumors that were recurrent or refractory. The registry lists several tumor types, including desmoplastic small round cell tumor, Ewing sarcoma/peripheral primitive neuroectodermal tumor, neuroblastoma, rhabdomyosarcoma, and malignant peripheral nerve sheath tumor. Enrollment was 1.
Intervention
A chemotherapy conditioning regimen followed by allogeneic hematopoietic stem cell transplantation. Listed interventions also include cyclosporine, mycophenolate mofetil, tacrolimus, and rabbit anti-thymocyte globulin, alongside chemotherapy agents.
Comparator
There was no separate control group. The registry classifies the study as single-group, with allocation recorded as not applicable. The treatment group therefore does not have a like-for-like control group for comparison.
Primary question
The primary objective was to assess tolerability of allogeneic hematopoietic cell transplantation in patients with chemo-responsive recurrent or refractory solid tumors. Tolerability was defined by transplant-related mortality by day +30 after transplant infusion.
In practical statistical terms, the central question was whether early transplant-related mortality could be assessed in this patient population after the conditioning regimen and transplant. The endpoint focuses on a specified early period and a serious outcome, rather than on tumor response or longer-term disease control. The registry lists a phase II study, but its record does not provide an analyzed estimate for this primary outcome.
The distinction between the intended question and the posted result is important. A primary endpoint can be defined in the registry even when the study does not produce an interpretable estimate. In this record, no analysis was performed because too few patients were enrolled for statistically significant conclusions. With enrollment of 1, the posted results do not establish a rate of transplant-related mortality for the broader population. They also do not permit a treatment-versus-control comparison, because the design has no control group.
3. Trial Design
The registry describes a phase II pilot study of allogeneic hematopoietic stem cell transplantation for pediatric and adolescent-young adult patients with high-risk solid tumors. The disease setting was recurrent or refractory cancer, and the primary endpoint was defined among patients whose tumors were chemo-responsive. The study was sponsored by M.D. Anderson Cancer Center and is recorded as terminated.
The design is single-group, with no allocation to competing treatment groups and no masking. Allocation is listed as not applicable. These design features mean that the posted results describe a treatment group rather than a randomized comparison. The trial cannot use a concurrent control group to separate treatment effects from other influences on outcomes.
The intervention combined chemotherapy conditioning with donor stem cell transplantation. The regimen description names thiotepa, etoposide, melphalan, and fludarabine phosphate, and describes their administration on specified days around the transplant. The intervention list also names cyclosporine, mycophenolate mofetil, tacrolimus, and rabbit anti-thymocyte globulin. The registry record does not provide a complete regimen description for every circumstance, so details beyond the recorded description are not reported in the registry record.
Enrollment was 1. The registry states that no analysis was performed because insufficient patients were enrolled for statistically significant conclusions. It records two outcome measures and zero analyses. The primary completion date is 2024-08-26, while the study status is terminated. The reason for termination is not reported in the registry record.
The registry gives a planning illustration based on an observed effect and assumptions involving two-sided significance level 0.05, equal allocation between two arms, and a normal approximation. Those assumptions do not describe the actual single-group design, and a planning illustration is not evidence of observed power. The registry does not report a trial-specific sample-size justification.
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 | Allogeneic Stem Cell Transplant in High Risk Solid Tumors |
|---|---|
| STARTED | 1 |
| COMPLETED | 0 |
| NOT COMPLETED | 1 |
Reasons for not completing this period:
| Reason | Allogeneic Stem Cell Transplant in High Risk Solid Tumors |
|---|---|
| Death | 1 |
Analysis population for the primary outcome, as defined in the registry: No analysis was performed as insufficient patients were enrolled for statistically significant conclusions.
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 | Allogeneic Stem Cell Transplant in High Risk Solid Tumors |
|---|---|---|
| Participants analysed | 1 | |
| Age, Categorical: <=18 years | Participants | 1 |
| Age, Categorical: Between 18 and 65 years | Participants | 0 |
| Age, Categorical: >=65 years | Participants | 0 |
| Age, Continuous | years | 12 (12 to 12) |
| Sex: Female, Male: Female | Participants | 0 |
| Sex: Female, Male: Male | Participants | 1 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 1 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 1 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 1 |
6. Primary Endpoint
The registry lists the primary outcome as Tolerability of Allogeneic HCT, measured over By day +30 after allogeneic HCT infusion.
| 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 tolerability of allogeneic hematopoietic cell transplantation, defined in the registry by transplant-related mortality (TRM) at day +30 after allogeneic HCT infusion. In plain terms, it asks whether death attributed to the transplant occurred within the specified early follow-up period. The endpoint is intended to capture an important safety outcome around transplantation, rather than measuring tumor shrinkage or duration of disease control.
General explanation: a time-bounded endpoint makes the observation period explicit. This can help distinguish an early treatment-related safety question from outcomes that require longer follow-up. A mortality endpoint is also direct in its event definition, although attribution to the transplant requires an assessment of cause. The registry’s definition names TRM, but the posted primary outcome does not include an analyzed value or a description of how attribution was assessed.
The registry says no analysis was performed because insufficient patients were enrolled for statistically significant conclusions. As a result, it does not report a primary endpoint estimate, uncertainty interval, or statistical test. The record therefore documents the endpoint that the study intended to assess, but does not supply an analyzed estimate of transplant-related mortality by day +30. This absence should not be replaced with an assumption that no event occurred: the primary outcome result is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a small pilot study with enrollment of 1 and a single-group design. It explicitly states that no analysis was performed because too few patients were enrolled for statistically significant conclusions. The record contains no analyses. Consequently, the intended primary endpoint—transplant-related mortality by day +30 after allogeneic HCT infusion—has no posted analyzed result.
This absence is not evidence that the endpoint was zero, nor does it establish that the intervention was tolerable or intolerable. It means the record does not report an analyzed finding for the primary question. The primary endpoint description explains what the study aimed to measure, but an endpoint definition is not itself an outcome result.
The design also limits what could be inferred even if an outcome estimate had been available. A single-group study has no concurrent comparator. An observed outcome would describe the enrolled group under the study conditions, but would not by itself establish what would have happened to comparable patients under another treatment strategy or without the transplant. The record further lists enrollment of only 1, so any patient-level observation would have very limited ability to represent the diverse tumor types named in the eligibility context.
There are adverse-event counts in the registry, but they should be read separately from the unanswered primary endpoint. The serious adverse event figures report 1 at risk and 0 affected; the other adverse event figures report 1 at risk and 1 affected; deaths are recorded as 1. The registry provides no serious adverse event terms. These counts do not state that the death was transplant-related, and they do not provide an attribution or an analyzed comparison. The primary endpoint therefore cannot be inferred from the death count alone.
General explanation: an estimate describes the observed data, while statistical uncertainty reflects how much the data leave unresolved about the population quantity of interest. With very limited enrollment, estimates—if available—would generally be imprecise and sensitive to the outcome of the enrolled patient. Here, however, the registry does not post an analyzed primary estimate or its uncertainty, so no precision assessment can be made from a primary endpoint analysis.
The record reports study termination, but not its reason. Termination should not be treated as evidence of a particular safety problem, lack of efficacy, or administrative cause. Likewise, the planning illustration described in the registry is not a result from this trial and cannot remedy the absence of a trial analysis. The supported conclusion is narrow: the study was intended to assess early transplant-related mortality, but the registry reports no analysis of that endpoint.
9. Statistical Methods Explained
Statistical methods explain how investigators turn observed outcomes into summaries that address a research question. For this study, the registry identifies the primary endpoint and the intended population, but reports no analysis. It does not report an analysis method, effect estimate, confidence interval, or hypothesis-test result for the primary outcome. The absence of these items means there is no statistical result to interpret for the primary question.
What does a single-group design allow?
General explanation: a single-group design observes outcomes among participants receiving the study intervention. It can describe what happened in that group, but it does not create a direct randomized contrast with another treatment. A comparison with a historical or external group would require additional information and assumptions; no such comparison is reported in this registry record. The study is classified as single-group, and the listed allocation is not applicable.
Because there is no control group, treatment effects cannot be estimated as differences between randomized arms. Even a clearly observed outcome would need careful interpretation: disease features, patient selection, clinical course, and other factors can influence outcomes. These are general considerations for uncontrolled clinical studies, not additional findings about this trial.
What does the endpoint definition contribute?
The endpoint is transplant-related mortality by day +30 after allogeneic HCT infusion. Defining the outcome and the follow-up period makes the intended assessment more specific. General explanation: endpoint definitions support consistent measurement by indicating what event is counted and within what time window. They do not, on their own, show how many events occurred, how events were attributed, or how uncertain an estimate would be. The registry does not post an analyzed primary endpoint value or details of an attribution method.
How should uncertainty be understood?
General explanation: a confidence interval is a range of values compatible with the observed data under a statistical model. It communicates uncertainty around an estimate; it is not a guarantee that the true value lies in that particular interval. A p-value, when used, describes how compatible the observed data are with a specified null model, under the assumptions of the test. Neither measure is reported for the primary endpoint in this record. With enrollment of 1 and no analysis, there is no posted estimate or interval from which to judge statistical precision.
General explanation: small samples tend to provide limited information about population outcomes, particularly when the outcome is uncommon. A study may have too little information to distinguish a genuine pattern from chance variation. The registry itself says the number enrolled was insufficient for statistically significant conclusions. That statement should not be translated into a claim that the treatment has no effect or that the endpoint did not occur; it describes the inability to draw the intended statistical conclusion.
What does the planning illustration mean?
The registry describes a planning illustration based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It describes time-to-event planning quantities as total events under the Schoenfeld approach, and other quantities as participants per arm. These are planning assumptions, not details of the actual trial design. In particular, the trial itself is single-group, not a two-arm study.
General explanation: sample-size planning asks how much information a future study might need under stated assumptions. Changing the target effect or other assumptions changes the planning result. A planning calculation does not show that a trial had a particular probability of detecting an effect after it was completed. It is not observed power, and it cannot substitute for an analysis of the outcomes actually recorded. The registry does not report a trial-specific sample-size justification or the assumptions underlying the original study design.
What can be inferred from the adverse-event counts?
Counts of participants at risk and affected describe recorded events in the safety group, but do not automatically establish causation or comparative risk. General explanation: interpreting adverse events requires attention to event definitions, time at risk, attribution, and completeness of reporting. The registry lists no serious adverse event terms and does not provide a statistical analysis of the adverse-event counts. These figures should therefore be read as descriptive registry entries, not as a comparative safety analysis.
Overall, the available record supports a description of design, intended endpoint, enrollment, and posted event counts. It does not support an inferential estimate of the primary endpoint. A detailed statistical analysis plan, handling of missing outcome data, interim analysis procedures, or population definitions beyond the registry text are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
Multiplicity concerns arise when a study tests several outcomes or hypotheses and then interprets the results as if only one test had been performed. General explanation: as the number of statistical tests increases, the chance of at least one apparently notable result can increase unless the analysis plan accounts for multiple testing. The registry identifies two outcome measures, but reports zero analyses. It does not describe a multiplicity adjustment or an approach for prioritizing multiple outcomes; these are not reported in the registry record.
Missing data are values that were intended to be collected but are unavailable or not reported. General explanation: missingness can affect estimates if the availability of data is related to outcomes or participant characteristics. The record does not provide a missing-data strategy, a participant flow description, or enough analyzed outcome information to assess completeness for the primary endpoint. The primary result is absent because no analysis was performed, according to the registry; the reason that no primary analysis appears is not further detailed.
The analysis population is also not specified beyond the registry’s statement that insufficient patients were enrolled for statistically significant conclusions. The record does not report an intention-to-treat, per-protocol, or safety analysis population, and it does not describe exclusions from an analysis. With enrollment of 1 and no analyses, comparisons among analysis populations cannot be evaluated.
General explanation: analysis populations matter because they define which participants contribute to a particular result. Different definitions can lead to different interpretations, especially when participants do not complete treatment or follow-up. No such population-specific results are available in this record. The appropriate reading is that the registry does not report multiplicity procedures, missing-data handling, or detailed analysis-population rules, rather than assuming any particular method was used.
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 |
|---|---|---|---|
| Allogeneic Stem Cell Transplant in High Risk Solid Tumors | 0 | 1 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Allogeneic Stem Cell Transplant in High Risk Solid Tumors | 1 of 1 |
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 |
|---|---|
| Allogeneic Stem Cell Transplant in High Risk Solid Tumors | 1 of 1 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Allogeneic Stem Cell Transplant in High Risk Solid Tumors |
|---|---|---|
| Alanine aminotransferase increased | Investigations | 1 of 1 |
| Anorexia | Metabolism and nutrition disorders | 1 of 1 |
| Aspartate aminotransferase increased | Investigations | 1 of 1 |
| Blood lactate dehydrogenase increased | Investigations | 1 of 1 |
| Creatinine Increase | Investigations | 1 of 1 |
| Diarrhea | Gastrointestinal disorders | 1 of 1 |
| Fatigue | General disorders | 1 of 1 |
| Fever | General disorders | 1 of 1 |
| Generalized Edema | General disorders | 1 of 1 |
| Hypertension | Vascular disorders | 1 of 1 |
The registry’s adverse-event group is titled “Allogeneic Stem Cell Transplant in High Risk Solid Tumors.” It records 1 participant at risk for serious adverse events and 0 affected. For other adverse events, it records 1 at risk and 1 affected. The death count is 1. No serious adverse event terms are listed.
These are registry counts, not a comparative safety analysis. The record does not give a serious event term to explain the serious-event count, and it does not provide an analysis linking the death to the transplant. The death count should not be interpreted as transplant-related mortality merely because the primary endpoint concerns TRM. The primary endpoint result is not reported in the registry record.
General explanation: safety counts describe events within a recorded group, but interpretation also depends on definitions, timing, attribution, and follow-up. Counts alone do not establish whether an event was caused by treatment, nor do they show how the same participants might have fared under another approach. Since this is a single-group study with enrollment of 1, the posted safety figures cannot support a controlled comparison. They should be read as descriptive entries, with the cause and clinical details not reported in the registry record.
12. What the Result Does, and Does Not, Mean
The record establishes that a phase II pilot study was intended to evaluate a chemotherapy-conditioned allogeneic hematopoietic stem cell transplant strategy for pediatric and adolescent-young adults with recurrent or refractory high-risk solid tumors. It identifies transplant-related mortality by day +30 as the primary measure of tolerability. It also records a single-group design, enrollment of 1, termination, and no statistical analysis.
Those details do not establish an estimate of the primary endpoint. The registry explicitly states that no analysis was performed because insufficient patients were enrolled for statistically significant conclusions. The primary outcome result is therefore not reported in the registry record. This is not equivalent to a finding of no mortality, no toxicity, or no treatment effect.
The safety entries record serious adverse events in 0 of the 1 participants at risk, other adverse events in 1 of the 1 participants at risk, and 1 death. These entries do not identify the serious event terms, establish cause, or show whether the death met the primary definition of transplant-related mortality. They also do not provide a comparison with another treatment group.
General explanation: statistical evidence depends not just on a study’s question, but on the amount and quality of outcome information collected and analyzed. A planned endpoint can be meaningful while the study remains unable to estimate it. In this record, the main limitation is not a conflicting statistical finding; it is the lack of an analyzed primary outcome and the very limited enrollment.
The record also does not establish why the study was terminated, whether any interim analyses occurred, or what statistical plan was intended. Such details are not reported in the registry record. The interpretation should therefore remain bounded to what the registry documents: the study’s purpose and design, the limited enrollment, the descriptive safety entries, and the absence of a primary statistical analysis.
13. Why This Trial Matters Statistically
This study matters statistically because it illustrates the gap between a carefully stated clinical question and the evidence available to answer it. The registry defines an early safety endpoint—transplant-related mortality by day +30—and describes a population with recurrent or refractory high-risk solid tumors. Yet enrollment was 1, and no analysis was performed. The question can be identified, but the posted record does not yield an analyzed estimate.
It also illustrates the limits of an uncontrolled design. A single-group study can document outcomes among treated participants, but it cannot directly compare those outcomes with a concurrent control group. That distinction matters when interpreting descriptive safety counts: they are not comparative evidence and do not establish what would have happened under another approach.
General explanation: statistical interpretation depends on both design and information. Design determines which comparisons are supported; the amount of observed information affects how precisely outcomes can be estimated. A planning illustration cannot replace either feature. The registry’s planning assumptions refer to equal allocation between two arms, while the trial is recorded as single-group. The illustration is therefore not a description of the completed study’s design and is not observed power.
The record is also a reminder that a missing analysis should not be converted into a positive or negative result. The primary endpoint was specified, but no analyzed value or uncertainty measure is posted. The adverse-event counts add descriptive context, but do not resolve the primary question or establish attribution. Statistically, the most defensible conclusion is about evidential limits: the registry records an intended endpoint and a very small enrollment, but no analysis capable of answering that endpoint for the target population.
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 direct limitation is enrollment of 1, together with the registry’s statement that no analysis was performed because insufficient patients were enrolled for statistically significant conclusions. The primary endpoint is defined, but an analyzed result is not reported. This prevents assessment of the estimated frequency or precision of transplant-related mortality by day +30.
The single-group design has no concurrent control group. It cannot support a direct treatment comparison, and the descriptive outcome entries cannot isolate the effect of transplantation from other influences. The registry lists multiple tumor types and recurrent or refractory disease settings, but the enrollment is too limited to characterize outcomes across that range of conditions.
The study is recorded as terminated, but the reason for termination is not reported in the registry record. The record also does not report a detailed statistical analysis plan, interim analyses, a trial-specific sample-size justification, handling of missing data, analysis-population definitions, or a method for attributing deaths to transplantation. These omissions limit interpretation, but do not establish that any particular method was or was not used outside what is recorded.
The adverse-event entries are sparse: the registry reports 1 at risk and 0 affected for serious adverse events, 1 at risk and 1 affected for other adverse events, and 1 death. No serious adverse event terms are listed. These data do not clarify timing, cause, or relationship to treatment, and are not a comparative safety analysis.
The planning illustration uses assumptions for a two-arm comparison, while the actual study is single-group. It should not be treated as evidence about the completed study’s statistical power or as a substitute for trial results. The registry record does not provide an analyzed primary outcome with which to make a population-level conclusion.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Donor Stem Cell Transplant After Chemotherapy for the Treatment of Recurrent or Refractory High-Risk Solid Tumors in Pediatric and Adolescent-Young Adults — NCT04530487.
- Registry record last updated 2025-06-29; status last verified 2025-06.
- Results first posted 2025-06-29.
- 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
NCT04530487 is a phase II pilot study sponsored by M.D. Anderson Cancer Center. It examined chemotherapy conditioning followed by allogeneic hematopoietic stem cell transplantation for pediatric and adolescent-young adults with recurrent or refractory high-risk solid tumors. The registry records a single-group design, no masking, enrollment of 1, and terminated status.
The primary endpoint was tolerability, defined as transplant-related mortality by day +30 after allogeneic HCT infusion. The registry reports two outcome measures and zero analyses, and states that no analysis was performed because insufficient patients were enrolled for statistically significant conclusions. The primary outcome result is not reported in the registry record.
Safety entries record 1 participant at risk and 0 affected for serious adverse events, 1 at risk and 1 affected for other adverse events, and 1 death. No serious adverse event terms are listed. The cause of termination, detailed analysis plan, and attribution of the death are not reported in the registry record.