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 Phase 2 Study of Rituximab-ABVD in Classical Hodgkin Lymphoma (NCT00369681), a na phase 2 study. The primary outcome is Effect of Rituximab on EBV(+) Tumors.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00369681 |
| Phase | Phase 2 |
| Condition | Lymphoma |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 51 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned patients with newly diagnosed stage II, stage III, or stage IV Hodgkin's lymphoma. The registry record reports enrollment of 51 participants. For the primary outcome, however, the relevant subgroup was the participants whose tumors were positive for Epstein-Barr virus (EBV); only 4 participants were in that subgroup.
Intervention
The treatment was rituximab given with ABVD chemotherapy. ABVD consists of doxorubicin, vinblastine, bleomycin, and dacarbazine. The listed regimen describes ABVD for 6-8 cycles, with rituximab scheduled during Cycle 1 and on Day 1 of Cycles 2, 4, and 6.
Comparator
This was a single-group study, and the registry lists allocation as not applicable. There is no control arm described in the record, so the study does not make a like-for-like randomized comparison between treatment strategies.
Primary question
The primary outcome asks for the number of relapses among participants with EBV-positive tumors, over a timeframe of up to 56 months. The registry record identifies the measure but does not report the relapse count. It therefore does not provide a result from which to estimate an effect or assess its precision.
3. Trial Design
The registry describes NCT00369681 as a phase II study of rituximab with combination chemotherapy for newly diagnosed Hodgkin's lymphoma. The study is marked completed. Its listed enrollment is 51. The registry record gives a start date of 2006-05 and a primary completion date of 2014-10.
The design is single group, with allocation listed as not applicable and masking listed as none. Participants received the R-ABVD regimen: ABVD chemotherapy for 6-8 cycles, with rituximab given at 375 mg/m² on Cycle 1 Days -6, 1, 8, 15, and 22, and at 375 mg/m² on Day 1 of Cycles 2, 4, and 6. These are the regimen details recorded; further information about treatment modifications, adherence, or the administration actually received is not reported in the registry record.
A single-group design can describe outcomes observed in participants receiving a regimen, but without a concurrent control group it cannot isolate the regimen's effect from other explanations for those outcomes. The record does not describe a randomized comparison. It also does not report a protocol rationale for the design, a sample-size justification, or details about any interim analyses.
The registry lists Event-free Survival and the addition of information to FDG-PET by plasma DNA biomarkers as secondary outcomes. The primary outcome is a count of relapses in the EBV-positive subgroup. The registry record does not report estimates or results for the primary outcome, and it does not provide enough analysis detail to establish how the listed outcomes were evaluated.
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: One subject withdrew consent prior to initiating the study.
Overall Study
| Stage | R-ABVD |
|---|---|
| STARTED | 50 |
| COMPLETED | 49 |
| NOT COMPLETED | 1 |
Reasons for not completing this period:
| Reason | R-ABVD |
|---|---|
| Death | 1 |
Analysis population for the primary outcome, as defined in the registry: Only 4 participants had EBV(+) tumors.
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-ABVD |
|---|---|---|
| Participants analysed | 49 | |
| Age, Continuous | years | 33 (18 to 66) |
| Sex: Female, Male: Female | Participants | 23 |
| Sex: Female, Male: Male | Participants | 26 |
| Region of Enrollment: United States | participants | 49 |
6. Primary Endpoint
The registry lists the primary outcome as Effect of Rituximab on EBV(+) Tumors, measured over Up to 56 months.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | relapses |
| Endpoint classification | not reduced to a single comparison |
The primary outcome is the number of relapses among participants whose tumors were positive for Epstein-Barr virus (EBV), with a timeframe of up to 56 months. The registry record states that only 4 participants had EBV-positive tumors. It identifies the outcome as a count; it does not report the number of relapses observed.
In general, a relapse count can describe how often recurrence was recorded in a specified population during a stated observation period. Restricting the outcome to participants with EBV-positive tumors defines a particular subgroup, rather than the entire enrolled population. Such a count is not, by itself, a measure of how quickly relapses occurred, nor does it establish how outcomes compare with another treatment. Interpretation also depends on how relapse was defined, how long each participant was followed, and how missing follow-up was handled; these details are not reported in the registry record.
The registry labels the primary outcome as the effect of rituximab on EBV-positive tumors, but the posted measure is a relapse count rather than a reported comparative effect estimate. With no relapse count or analysis result reported, the endpoint cannot establish the observed outcome in this subgroup or the precision of any estimate.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a phase II, single-group study of rituximab with ABVD chemotherapy and lists enrollment of 51. Its primary outcome is the number of relapses among participants with EBV-positive tumors over up to 56 months. The record states that only 4 participants had EBV-positive tumors, but it does not report the relapse count. No primary-outcome estimate or analysis result is available in the registry record, so the observed result and its precision cannot be interpreted.
The subgroup size is important context for reading the outcome. General statistical principle: estimates based on small subgroups tend to have substantial uncertainty, and a count alone gives no direct indication of that uncertainty. A confidence interval, when reported, describes a range of values compatible with the data and the stated statistical method. No confidence interval for the primary outcome is reported in the registry record. It is therefore not possible to quantify the uncertainty around the subgroup result.
The single-group design also limits what can be concluded. Outcomes observed after treatment would describe participants in this study, but there is no concurrent control group in the registry record for a direct comparison. General statistical principle: without a suitable comparison, an outcome cannot be attributed to the treatment alone, because differences in participant characteristics, disease course, or other factors may also contribute. The registry lists allocation as not applicable and masking as none.
The registry lists Event-free Survival and the addition of information to FDG-PET by plasma DNA biomarkers as secondary outcomes. It does not report analyses for these outcomes in the registry record for this account. There are zero analyses listed, and no effect estimates or uncertainty measures are available to evaluate. A completed status does not itself establish that results were reported or that a treatment effect was demonstrated.
The safety record lists 50 participants at risk in the R-ABVD group for both serious and other adverse events, with 16 affected in the serious category and 0 in the other category. It also lists 1 death. The record does not describe whether the death was treatment-related. The listed serious-event terms and their percentages give additional safety information, but without definitions, participant-level overlap, or context about attribution, they should not be interpreted as comparative treatment risks.
9. Statistical Methods Explained
General statistical concepts help distinguish what a trial design can show from what its results can establish. In this study, the registry describes a single group receiving R-ABVD, a primary outcome based on relapse counts in an EBV-positive subgroup, and no reported primary analysis. Those features place clear limits on the conclusions that can be drawn.
What does a single-group design estimate?
General: a single-group study records outcomes in participants who receive a particular regimen. It can describe the observed experience of that group, provided the outcomes and follow-up are reported. A treatment effect is a comparison: it asks how outcomes differ between the treatment received and an appropriate alternative. With no control group in the registry record, there is no direct estimate of that contrast. Even if an outcome were reported, a change or event count in one group would not by itself show what would have happened to comparable participants under another approach.
Randomization, when used, aims to make treatment groups comparable on average at the start of a study. This record lists allocation as not applicable and describes a single group. It therefore does not report a randomized treatment comparison. Masking is listed as none; the record does not give more detail about how outcomes were assessed or whether particular assessments involved judgment.
How should a relapse count be read?
General: a count records how many events were observed in a defined group, but its meaning depends on the observation process. Follow-up duration, loss to follow-up, event definitions, and whether participants could have more than one event can affect interpretation. A count also differs from a time-to-event estimate, which incorporates when events occur and how long participants are observed. The registry's primary outcome is described as the number of relapses among EBV-positive participants, with a timeframe of up to 56 months. It does not report the count, the relapse definition, individual follow-up, or an analysis method.
The subgroup includes only 4 participants according to the record. General: estimates from small groups are often imprecise because each participant's outcome can have considerable influence on the total. A confidence interval is a statistical range that expresses uncertainty around an estimate under a specified model and assumptions. No interval or other uncertainty measure is reported for the primary outcome, so its precision cannot be assessed from the record.
What do the planning assumptions mean?
The registry's sample-size assumptions describe planning illustrations based on an observed effect, not the trial's own design. They specify a two-sided significance level of 0.05, equal allocation between two 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 illustrations use a total number of events, while other outcomes use participants per arm. These are planning conventions, not evidence that the study enrolled two arms or used that design. The study itself is listed as single group.
General: a sample-size calculation asks what enrollment or event total might be needed under a particular set of assumptions to detect a specified effect with a chosen statistical procedure. Its result depends on those assumptions. It is not observed power, and it does not establish that an effect occurred. The registry record does not report the trial's own sample-size justification. No planning values are because the record details do not state those calculated values.
Why do adjustment and model details matter?
General: statistical models summarize data under assumptions. For count outcomes, the appropriate approach depends on such features as how counts arise, whether observations are independent, and whether variability exceeds what a chosen model expects. Over-dispersion means that count variability is greater than a model allows; if ignored, uncertainty estimates can be misleading. The record does not report a model for the primary count, or enough outcome data to assess its distribution. No model should be inferred from the endpoint description alone.
A confidence interval and a significance test answer related but different questions. A test evaluates data against a specified null hypothesis under a statistical model, while an interval communicates uncertainty in an estimate. Neither can be interpreted without knowing the analysis and the data. The registry record does not report a primary-outcome estimate, test, confidence interval, or analysis method.
Multiplicity arises when several outcomes or comparisons are tested. General: the more tests considered, the greater the chance that at least one result may appear notable by chance if no adjustment or interpretation plan is used. The record lists secondary outcomes, but it does not report a multiplicity strategy or analysis results. The posted record therefore does not permit assessment of how multiple outcomes were handled.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists a primary outcome and secondary outcomes, but does not report a multiplicity strategy. General statistical principle: when several outcomes or comparisons are tested, interpretation depends on whether the analyses were prespecified and whether any adjustment or hierarchy was used. Without those details, readers cannot determine how the chance of false-positive findings was managed. The record also lists zero analyses, so it does not provide outcome estimates or tests to evaluate.
Missing-data methods are not reported in the registry record. The record does not describe the extent or reasons for missing outcome information, how participants lost to follow-up were handled, or whether any imputation or sensitivity analysis was performed. These omissions matter because incomplete follow-up can affect an event count and the interpretation of a time-to-event outcome.
The analysis populations are not described in the registry record. In particular, it does not state which participants were included in analyses, how treatment exposure or protocol deviations were handled, or whether the primary analysis included every participant with an EBV-positive tumor. The record says only 4 participants had EBV-positive tumors, making the definition of the analyzed subgroup especially relevant.
These reporting gaps do not establish that a method was absent from the study; they mean that the method is not reported in the registry record. The record does not give enough information to assess prespecification, missingness, or the analysis population for the outcomes.
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-ABVD | 16 | 50 | 32.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| R-ABVD | 1 of 50 |
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 |
|---|---|
| R-ABVD | 0 of 50 |
Most frequent serious adverse event terms
| Event term | Organ system | R-ABVD |
|---|---|---|
| Non-neutropenic infection | Infections and infestations | 9 of 50 |
| Febrile neutropenia | Blood and lymphatic system disorders | 7 of 50 |
| Thrombosis | Vascular disorders | 4 of 50 |
| Other, not specified | Investigations | 4 of 50 |
| Pulmonary toxicity | Respiratory, thoracic and mediastinal disorders | 3 of 50 |
Serious events with the highest arm-level rate: non-neutropenic infection (18.0%), febrile neutropenia (14.0%), thrombosis (8.0%), other, not specified (8.0%), pulmonary toxicity (6.0%).
The R-ABVD safety group lists 50 participants at risk for serious adverse events and 16 affected. For other adverse events, the record lists 50 at risk and 0 affected. It also lists 1 death. The record does not report whether the death was attributed to treatment, nor does it provide additional detail about the timing or circumstances of the death.
The registry lists these serious adverse-event terms and percentages: non-neutropenic infection, 18.0%; febrile neutropenia, 14.0%; thrombosis, 8.0%; other, not specified, 8.0%; and pulmonary toxicity, 6.0%. These figures are reported as percentages, but the record does not specify the event definitions or give further details about how each term was counted. It also does not say whether a participant could contribute to more than one category. The percentages should therefore not be added together or read as mutually exclusive categories.
General: adverse-event summaries describe events recorded during a study; they do not by themselves establish that treatment caused an event. The registry record does not provide a comparison group or enough attribution information to make a comparative safety assessment.
12. What the Result Does, and Does Not, Mean
The registry record establishes that NCT00369681 was a completed phase II, single-group study of rituximab with ABVD chemotherapy in newly diagnosed stage II, stage III, or stage IV Hodgkin's lymphoma. It records enrollment of 51 and describes a primary outcome focused on relapse counts among participants with EBV-positive tumors. It states that only 4 participants had EBV-positive tumors.
The record does not report the primary relapse count, an estimate of treatment effect, a confidence interval, or a statistical test. It consequently does not establish the observed outcome in the EBV-positive subgroup or how precisely that outcome was estimated. The listed secondary outcomes also have no analysis results in the available record details. A trial marked completed is not, by that status alone, evidence of a positive or negative result.
The design does not support a direct comparison with another treatment because it is single group and has no control arm described. General: a treatment effect requires a comparison that can distinguish outcomes under alternative approaches. Descriptive outcomes from one group cannot by themselves show that the treatment caused those outcomes. The registry record also does not report an analysis plan, missing-data methods, or outcome definitions in enough detail to resolve those issues.
The safety entries provide a limited description of recorded adverse events in the R-ABVD group: 16 participants were affected in the serious category, 0 in the other category, and 1 death was listed. The record does not establish causation or provide a comparative safety estimate. The serious-event percentages should be read as the registry's reported categories, not as a complete account of all possible risks.
Overall, the record documents the study design, regimen, and selected safety information, but does not report the primary result needed to answer its stated endpoint question. It cannot support a conclusion about whether rituximab changed relapse outcomes in the EBV-positive subgroup.
13. Why This Trial Matters Statistically
This study raises a useful statistical distinction between a trial's stated clinical question and the evidence available in its registry record. The primary outcome is framed around the effect of rituximab on EBV-positive tumors, yet the recorded measure is a relapse count among only 4 EBV-positive participants, and the count itself is not reported. Without the result and an uncertainty estimate, the endpoint cannot be interpreted quantitatively.
The design also makes the comparison question important. The record describes a single group and no control arm. General: observing outcomes after a regimen is different from estimating how outcomes compare with an alternative. The distinction matters because treatment attribution depends on an appropriate comparison, not simply on the presence of a treatment and an outcome measure.
The record illustrates why outcome definitions, follow-up, analysis populations, and missing-data methods matter. A count of relapses over up to 56 months is interpretable only with context about event definitions and participant observation. Those details, as well as the analysis method and primary estimate, are not reported in the registry record.
It also illustrates a difference between statistical planning and trial design. The listed planning assumptions describe hypothetical two-arm sample-size illustrations, while the registered study is single group. Such planning calculations do not turn a single-group study into a comparative trial and are not observed power. Clear separation of design, outcome reporting, and planning assumptions helps readers avoid treating a calculation or a completed status as evidence of a treatment effect.
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 main limitation for interpreting the primary question is that the registry record identifies the relapse-count endpoint but does not report its result. Only 4 participants had EBV-positive tumors, and no estimate, uncertainty interval, or analysis is reported for that subgroup. The outcome timeframe is listed as up to 56 months, but the record does not state how follow-up varied among participants.
The study is described as single group, with allocation not applicable and no control arm reported. It therefore does not provide a direct treatment comparison. Masking is listed as none, while further details about outcome assessment are not reported in the registry record. The record also does not report relapse criteria, protocol deviations, treatment completion, or how exposure to the regimen was analyzed.
Other methodological details are absent from the registry record: the sample-size justification, statistical analysis plan, interim analyses, analysis populations, missing-data handling, and multiplicity approach. These omissions prevent an assessment of whether the analyses followed a prespecified plan or how incomplete observations were addressed. No primary or secondary analysis results are listed in the record details used for this account.
The safety summary is also limited. It gives the number at risk and affected for serious and other adverse-event categories, lists selected serious-event terms and percentages, and records 1 death. It does not report attribution, event-level detail, or whether categories overlap. These limits mean the safety entries cannot be interpreted as comparative or causal estimates.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Phase 2 Study of Rituximab-ABVD in Classical Hodgkin Lymphoma — NCT00369681.
- Registry record last updated 2018-08-27; status last verified 2018-07.
- Results first posted 2015-07-03.
- 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
NCT00369681 is a completed phase II, single-group study of rituximab with ABVD chemotherapy in newly diagnosed stage II, stage III, or stage IV Hodgkin's lymphoma. The registry records enrollment of 51, a start date of 2006-05, and a primary completion date of 2014-10. Allocation is listed as not applicable and masking as none.
The primary outcome is the number of relapses among participants with EBV-positive tumors over up to 56 months. The record states that only 4 participants had EBV-positive tumors but does not report the relapse count or an analysis result. Secondary outcomes listed are Event-free Survival and the addition of information to FDG-PET by plasma DNA biomarkers.
The R-ABVD group lists 50 participants at risk for serious and other adverse events, 16 affected in the serious category, 0 in the other category, and 1 death. The registry record does not report a control group or enough analysis detail to estimate a comparative treatment effect.