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 Combination Chemotherapy and Rituximab in Treating Patients With Newly Diagnosed Burkitt's Lymphoma or Leukemia (NCT00133991), a na phase 2 study. The primary outcome is Overall Response Rate.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00133991 |
| Phase | Phase 2 |
| Condition | Leukemia, Lymphoma |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 23 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins |
| Results posted | Yes |
2. Clinical Question
Population
Adults with newly diagnosed Burkitt or Burkitt-like lymphoma or leukemia were the intended population. The registry record identifies leukemia and lymphoma as conditions and describes newly diagnosed disease, but does not report further eligibility details or the participants’ clinical characteristics.
Intervention
The study evaluated a regimen called R-CVP + HiCy. The description includes two fifteen-day cycles of cyclophosphamide, vincristine, prednisone, and rituximab, with filgrastim support. It also describes central nervous system treatment with cytarabine and hydrocortisone for three days and methotrexate for one day in each cycle, with leucovorin support.
Comparator
There was no comparator group. The study is recorded as single-group, with no allocation to distinct treatment arms. Consequently, the registry record does not provide a concurrent control against which to estimate a treatment difference.
Primary question
The primary question was how many participants had a complete or partial remission, using the 2007 International Working Group criteria, within the endpoint timeframe of up to 3 months. The registry record states that 4 participants who died during treatment were not analyzed for this outcome. It does not report the response count or an overall response estimate.
In statistical terms, this is a question about the observed response experience in a treated group, rather than a randomized comparison of outcomes under two treatments. The study can describe responses among those included in the endpoint analysis, but without a comparator it cannot establish how those outcomes differ from another treatment or from the course participants would otherwise have experienced. The registry record does not report a hypothesis test or a precision estimate for the primary endpoint.
3. Trial Design
This was a phase II, single-group study with no masking. The registry record lists enrollment of 23 participants and identifies the sponsor as Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins. The recorded start was 2005-07, primary completion was 2011-08, and the status is completed. Those dates describe the trial record, not the timing of individual outcomes.
The treatment was a combination regimen. Its description specifies two fifteen-day cycles of cyclophosphamide, vincristine, prednisone, and rituximab, with filgrastim support. It also describes central nervous system treatment during each cycle: cytarabine and hydrocortisone for three days, followed by methotrexate for one day with leucovorin support. The registry record lists these agents among the interventions. Further details about dose, schedule adjustments, treatment completion, or changes in the regimen are not reported in the registry record.
A single-group design means that all participants were enrolled into the same treatment group, rather than assigned between treatment groups. With no randomized comparator and no masking, the study’s reported outcome is a description of what happened in the enrolled group. It is not a direct estimate of the difference between this regimen and an alternative. The allocation field is recorded as not applicable, consistent with the single-group description.
The registry record identifies overall response rate as the primary outcome, measured as the number of participants with complete or partial remission according to the 2007 International Working Group criteria. Its timeframe is up to 3 months. Relapse pattern is listed as a secondary outcome. Five outcome measures are recorded, but formal analysis records are absent. A detailed protocol, a statistical analysis plan, the rationale for the enrollment target, and details of any interim monitoring are not reported in the registry record.
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.
Before assignment: 2 participants were found to be HIV+ after initiating the study and are considered to be screen failures as defined by the protocol.
Overall Study
| Stage | R-CVP + HiCy |
|---|---|
| STARTED | 21 |
| COMPLETED | 17 |
| NOT COMPLETED | 4 |
Reasons for not completing this period:
| Reason | R-CVP + HiCy |
|---|---|
| Death | 4 |
Analysis population for the primary outcome, as defined in the registry: The 4 participants who died during treatment were not analyzed for this outcome.
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 | R-CVP + HiCy |
|---|---|---|
| Participants analysed | 21 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 17 |
| Age, Categorical: >=65 years | Participants | 4 |
| Age, Continuous | years | 53 (34 to 75) |
| Sex: Female, Male: Female | Participants | 7 |
| Sex: Female, Male: Male | Participants | 14 |
6. Primary Endpoint
The registry lists the primary outcome as Overall Response Rate, measured over Up to 3 months.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint counts participants who had either a complete remission or a partial remission, according to the 2007 International Working Group criteria. Its timeframe is up to 3 months. The outcome is expressed as a count of participants, not as a time-to-event measure or a continuous measurement. The registry record states that the 4 participants who died during treatment were not analyzed for this endpoint.
Response endpoints are used in clinical trials to describe whether participants meet prespecified criteria for a change in disease status. Combining complete and partial remission into an overall response count provides a summary of participants meeting either response category. It does not, by itself, describe how long a response lasted, whether disease later returned, or how participants fared on other outcomes. Relapse pattern is listed separately as a secondary outcome, but its results are not reported in the registry record.
The registry record gives the endpoint definition and analysis exclusion but does not give the number who achieved complete remission, the number who achieved partial remission, or the combined response count. It also does not report the endpoint’s denominator beyond noting the exclusion of participants who died during treatment. Therefore, an overall response proportion, confidence interval, or test of a response hypothesis cannot be described from the registry record. The outcome definition alone is not evidence of the result.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical limitation is that the registry record defines the primary outcome but does not report its observed result. It specifies a count of participants with complete or partial remission, assessed using the 2007 International Working Group criteria over up to 3 months. It also states that 4 participants who died during treatment were not analyzed for this outcome. However, the response count and the resulting endpoint estimate are not reported in the registry record. The primary result therefore cannot be quantified or interpreted as an observed response frequency.
The enrollment was 23, while the primary endpoint excludes the 4 participants who died during treatment. These registry entries identify that the endpoint analysis did not include everyone enrolled, but they do not establish the complete endpoint denominator or explain how every participant’s outcome was handled. The safety information separately lists 21 participants at risk in the R-CVP + HiCy group. The registry record does not explain how these analysis populations relate to enrollment or to the endpoint exclusions, so they should not be treated as interchangeable denominators.
Because this is a single-group study, there is no concurrent control group for estimating a treatment contrast. Even if a response count had been reported, it would describe outcomes in the treated group rather than establish the difference attributable to treatment compared with another approach. Comparisons with outcomes from other settings would require information and assumptions not reported in the registry record. No causal conclusion follows from the design alone.
Formal analysis records are not listed, and the registry record does not report a confidence interval, hypothesis test, or adjusted estimate for the primary outcome. General statistical interpretation: a confidence interval conveys the precision of an estimate by describing a range of values compatible with the data and the method used. Without a reported response estimate and interval, the precision of the primary outcome cannot be assessed. The absence of an analysis record does not prove that no analysis was conducted; it means that the registry record does not supply a result to interpret.
The safety summary lists serious adverse events for 21 participants at risk, with 12 affected, and other adverse events with 21 at risk and 21 affected. It also lists 9 deaths. These figures describe safety reporting in the registry, but the record does not give the timing, attribution, or overlap among categories. They should not be combined with the primary endpoint or used to infer an explanation for the endpoint exclusions.
Overall, the record supports a description of the design, endpoint definition, enrollment, and selected safety counts. It does not support a numerical conclusion about overall response, the precision of that response, or a comparison with another treatment.
9. Statistical Methods Explained
The statistical information available in the registry record is limited. The design is single-group, the primary endpoint is a participant count, and the outcome definition includes complete or partial remission by specified criteria. Formal analysis records are not listed. The record does not report a detailed statistical analysis plan, a hypothesis test, a confidence interval, or adjusted results for the primary endpoint. The explanations below distinguish general statistical concepts from the methods actually documented for this study.
What does a single-group design estimate?
In general, a single-group study describes the outcomes observed among participants who received the study regimen. If a response count and an appropriate denominator are reported, they can be used to summarize the observed response proportion in that group. A single-group result is not a randomized treatment contrast: there is no concurrently assigned comparison group to account for differences in disease characteristics, care, or other influences on outcomes. For this study, the registry record does not report the primary response count, so even a numerical description of the observed response proportion is unavailable.
What does the endpoint count?
The endpoint counts participants meeting either of two response categories: complete remission or partial remission according to the 2007 International Working Group criteria. This is a binary classification at the participant level for purposes of the overall response endpoint: a participant either meets the endpoint definition or does not. The stated timeframe is up to 3 months. The record does not describe any additional assessment schedule or rules for handling evaluations outside that timeframe.
General statistical explanation: a count records the number of participants with the event of interest, while a proportion relates that count to a defined denominator. The denominator matters because it determines which participants’ outcomes are represented. Here, the registry record says that 4 participants who died during treatment were not analyzed for the primary endpoint, but does not fully report the analysis denominator or the handling of all other participants. A response proportion should not be reconstructed from enrollment alone.
What would a confidence interval contribute?
General statistical explanation: an estimate from a sample is subject to uncertainty. A confidence interval expresses that uncertainty using a range calculated under a specified statistical method. A narrower interval generally indicates greater precision, while a wider interval indicates more uncertainty. An interval does not remove limitations such as selection, missing outcomes, or the absence of a comparator. No confidence interval for the primary endpoint is reported in the registry record, and without the endpoint estimate its precision cannot be assessed.
What can be inferred from the analysis records?
The registry record lists five outcome measures and zero analysis records. This means that no formal analysis entries are present in the record. It does not establish whether analyses were performed outside the registry, whether results were evaluated using other methods, or what decisions were made during study conduct. The analysis model, covariate adjustment, handling of repeated assessments, and any prespecified testing procedure are not reported in the registry record. They should not be inferred from the endpoint name or the study phase.
How should the sample-size assumptions be read?
The registry record describes a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It also states that the effect to detect is a stated fraction of the observed effect. The record does not report the resulting participant counts in the information available for this analysis, nor does it report the original trial’s sample-size justification. The illustration’s equal-allocation, two-arm assumptions do not describe the recorded single-group study design. It is a planning exercise, not a reconstruction of the trial’s design or evidence of achieved statistical power.
General statistical explanation: power is a design-stage probability of detecting a specified effect under stated assumptions if that effect is true. A calculation using an effect observed in a study is especially dependent on that estimated effect and the planning assumptions. Such a calculation is not observed power and cannot substitute for an estimate with its uncertainty. Because the primary result is not reported, the response effect and its precision cannot be assessed from the registry record.
Why do analysis populations matter?
Different outcomes can have different analysis populations. A safety summary may count participants who were at risk of an adverse event, while an efficacy endpoint may exclude participants who did not meet an outcome-analysis rule. General statistical explanation: clear population definitions help readers understand who contributes to each estimate and how missing or unavailable outcomes affect interpretation. The registry record identifies 23 enrolled participants, says that 4 deaths during treatment were excluded from the primary endpoint analysis, and lists 21 at risk for safety outcomes. It does not reconcile these figures or report a complete participant disposition. Each figure should therefore be read in its stated context, not used as a substitute denominator for another outcome.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists five outcome measures and identifies overall response rate as the primary outcome. Relapse pattern is named as a secondary outcome. It does not report how many hypotheses were tested, whether any outcomes were grouped into a testing hierarchy, or whether statistical significance was adjusted for multiple comparisons. A multiplicity strategy is not reported in the registry record.
General statistical explanation: when several outcomes or comparisons are tested, the chance of at least one apparently notable result can increase. Prespecified priorities and adjustment methods can help make confirmatory interpretation clearer. Without a documented testing plan and analysis results, it is not possible to determine how multiplicity was handled or how any reported result should be classified as confirmatory. The registry record does not supply formal analysis entries for the listed outcomes.
For the primary outcome, the registry states that 4 participants who died during treatment were not analyzed. It does not report how other participants with unavailable or incomplete response assessments were handled, whether any assessments were missing, or whether sensitivity analyses were conducted. The reason for excluding those who died is given as a population statement, but the statistical plan for handling such cases is not reported in the registry record. No imputation method or missing-data assumption is described.
The record also does not provide a complete account of participants assessed for each outcome. Enrollment was 23, while the safety group lists 21 participants at risk. These are distinct reported details; the relationship between them is not explained. Without a participant disposition and outcome-specific denominators, the extent and possible influence of missing data cannot be evaluated.
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 |
|---|---|---|---|
| R-CVP + HiCy | 12 | 21 | 57.1% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| R-CVP + HiCy | 9 of 21 |
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 |
|---|---|
| R-CVP + HiCy | 21 of 21 |
Most frequent serious adverse event terms
| Event term | Organ system | R-CVP + HiCy |
|---|---|---|
| Febrile neutropenia | Infections and infestations | 2 of 21 |
| Acute respiratory distress syndrome | Respiratory, thoracic and mediastinal disorders | 1 of 21 |
| Ascites | Hepatobiliary disorders | 1 of 21 |
| Atrial fibrillation | Cardiac disorders | 1 of 21 |
| Blood infection | Infections and infestations | 1 of 21 |
| Colitis | Gastrointestinal disorders | 1 of 21 |
| Dyspnea | Respiratory, thoracic and mediastinal disorders | 1 of 21 |
| Encephalitis | Infections and infestations | 1 of 21 |
| Hypotension | Cardiac disorders | 1 of 21 |
| Hypoxia | Respiratory, thoracic and mediastinal disorders | 1 of 21 |
Most frequent non-serious adverse event terms
| Event term | Organ system | R-CVP + HiCy |
|---|---|---|
| Headache | General disorders | 11 of 21 |
| Dyspnea | Respiratory, thoracic and mediastinal disorders | 10 of 21 |
| Constipation | Gastrointestinal disorders | 9 of 21 |
| Neuropathy | Nervous system disorders | 9 of 21 |
| Pain - back | Musculoskeletal and connective tissue disorders | 9 of 21 |
| Leukopenia | Investigations | 8 of 21 |
| Fatigue | General disorders | 7 of 21 |
| Hypotension | Cardiac disorders | 7 of 21 |
| Pain - abdomen | Musculoskeletal and connective tissue disorders | 7 of 21 |
| Vomiting | Gastrointestinal disorders | 7 of 21 |
Serious events with the highest arm-level rate: febrile neutropenia (9.5%), acute respiratory distress syndrome (4.8%), ascites (4.8%), atrial fibrillation (4.8%), blood infection (4.8%).
The serious adverse event summary for R-CVP + HiCy lists 21 participants at risk and 12 affected. The separate summary for other adverse events lists 21 at risk and 21 affected. The group also lists 9 deaths. These are registry safety counts; the record does not provide the timing, attribution to treatment, or the relationship between these counts and the primary endpoint population.
The listed serious adverse event terms include febrile neutropenia at 9.5%, acute respiratory distress syndrome at 4.8%, ascites at 4.8%, atrial fibrillation at 4.8%, blood infection at 4.8%, and colitis at 4.8%. These percentages should be read as the registry’s reported values, not recalculated from the counts. The record does not explain whether participants could contribute more than one event term, or whether the terms represent unique participants. They therefore should not be added together to estimate the number affected.
General statistical explanation: a participant count, an event count, and a percentage can answer different questions. The safety record presents affected-participant counts and selected event-term percentages, but does not describe all details needed to compare risks across treatments. There is no control group, and the record does not identify causality for these events. These figures describe reported safety experience in the study group; they do not by themselves establish comparative safety.
12. What the Result Does, and Does Not, Mean
The registry record establishes that this was a completed phase II, single-group study of R-CVP + HiCy and that overall response was the primary outcome. It defines response as complete or partial remission by the 2007 International Working Group criteria, within up to 3 months. It reports enrollment of 23 and states that 4 participants who died during treatment were not analyzed for the primary endpoint. It also reports selected safety counts and event terms.
What the record does not establish is the observed overall response result. The response count, denominator, and any estimate of response frequency are not reported in the registry record. There is also no reported confidence interval or formal test for that endpoint. As a result, the magnitude and precision of the primary outcome cannot be described from these entries.
The single-group design does not include a concurrent comparator. Even if the response result were available, it would describe outcomes within this treated group, rather than estimate how outcomes differ from a control treatment. A comparison with another study or population would require comparable definitions, populations, follow-up, and analysis methods, none of which are detailed for such a comparison in the registry record.
The safety counts provide a separate description of adverse events and deaths in the study group. The registry does not report enough detail to establish event attribution, overlap, or comparative risks. These data should not be interpreted as proof that the regimen caused or prevented any particular outcome.
General statistical explanation: statistical evidence is strongest when the outcome definition, analysis population, estimate, uncertainty, and comparison design are all clear. Here, the endpoint definition is available, but the primary numerical result and several analysis details are not. The appropriate conclusion is therefore about what was registered and how the endpoint was defined, not about the size or reliability of an unreported response effect.
13. Why This Trial Matters Statistically
This trial illustrates why a clearly named primary endpoint is not enough to support a statistical conclusion. The registry record specifies an overall response outcome and its criteria, but does not report the response count or an estimate. Readers therefore cannot judge either the observed response frequency or its precision from the primary outcome entry.
The study also highlights the distinction between describing an outcome and estimating a treatment effect. A single-group design can document outcomes among enrolled participants, but it does not provide a randomized comparison. Without a concurrent control, observed outcomes cannot be interpreted as a difference attributable to the regimen. This distinction remains important even when a trial has a defined phase, treatment schedule, and outcome timeframe.
Analysis populations also require attention. Enrollment was 23, the primary outcome excludes 4 participants who died during treatment, and the safety summary lists 21 participants at risk. The record does not explain the relationship among these groups. Statistical interpretation depends on knowing who contributed to each outcome and how unavailable outcomes were handled; those details are incomplete.
Finally, the record contains safety counts and event-term percentages but does not report attribution, timing, or overlap. Such summaries can help describe the recorded safety experience, yet they are not a controlled comparison. The case reinforces a general principle: design, outcome reporting, denominator clarity, and uncertainty estimates all shape what conclusions are supported. When key results are absent, restraint is part of accurate statistical interpretation.
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.
Several limitations specific to this registry record constrain interpretation. Most importantly, the primary outcome result is not reported. Although the endpoint definition and the exclusion of 4 participants who died during treatment are stated, the response count, complete analysis denominator, response proportion, and uncertainty estimate are absent. The endpoint cannot be numerically summarized from the record.
The single-group design has no concurrent comparator, so it cannot provide a randomized estimate of a treatment difference. The record also does not report participant characteristics, detailed eligibility criteria, or a complete account of participant disposition. These omissions make it difficult to assess which enrolled participants contributed to each outcome or how representative the study group may be of the intended population.
The relationship between the 23 enrolled participants and the 21 participants listed as at risk in the safety summary is not explained. Reasons for any difference, outcome-specific denominators, and the handling of missing assessments beyond the stated deaths are not reported in the registry record. Nor are sensitivity analyses or imputation methods described.
Formal analysis entries are absent. The registry record does not document a statistical analysis plan, methods for confidence intervals or hypothesis tests, adjustment for multiplicity, or interim monitoring. It also does not report the trial’s own sample-size justification. The planning illustration described in the record uses assumptions for two arms, unlike the recorded single-group design, and does not supply a primary outcome result.
Safety interpretation is limited by the absence of reported event timing, treatment attribution, and overlap among event categories. These limitations do not establish that analyses or details were absent from all study materials; they describe what is not reported in the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Combination Chemotherapy and Rituximab in Treating Patients With Newly Diagnosed Burkitt's Lymphoma or Leukemia — NCT00133991.
- Registry record last updated 2018-09-17; status last verified 2018-09.
- Results first posted 2018-09-17.
- 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
This completed phase II study enrolled 23 participants and evaluated R-CVP + HiCy in adults with newly diagnosed Burkitt or Burkitt-like lymphoma or leukemia. It was recorded as a single-group, unmasked study, with no comparator group. The primary endpoint was the count of participants with complete or partial remission under the 2007 International Working Group criteria, assessed up to 3 months. The registry states that 4 participants who died during treatment were not analyzed for this outcome.
The primary response result and its precision are not reported in the registry record. Relapse pattern is listed as a secondary outcome. Safety entries list 21 participants at risk, 12 affected by serious adverse events, 21 affected by other adverse events, and 9 deaths. The record does not report event attribution or reconcile the safety and efficacy populations. Formal analysis entries are absent, and the record does not provide a detailed statistical plan or sample-size justification.