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 Lenalidomide and Rituximab as Treatment of Chronic Lymphocytic Leukemia (NCT00759603), a na phase 2 study. The primary outcome is Overall Participant Response Rate: Percentage of Participants With Complete + Partial Response According to Revised National Cancer Institute-sponsored Working Group Guidelines.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00759603 |
| Phase | Phase 2 |
| Condition | Chronic Lymphocytic Leukemia, Small Lymphocytic Lymphoma |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 60 |
| Arms in the primary outcome | n/a |
| Lead sponsor | M.D. Anderson Cancer Center |
| Results posted | Yes |
2. Clinical Question
Population
The study concerns patients with chronic lymphocytic leukemia or small lymphocytic lymphoma who had already received therapy. The registry record lists an enrollment of 60, but does not report the detailed eligibility criteria, baseline characteristics, or the number who received treatment or were included in the endpoint analysis.
Intervention
The treatment was lenalidomide in combination with rituximab. Lenalidomide was oral, at 10 mg/day, beginning on Day 9 of cycle 1. Rituximab was given intravenously on Day 1, Day 8, Day 15 and Day 22, then once every four weeks during cycles 3-12 (+ 7 days). Rituximab was not given in Cycle 2; treatment duration was twelve cycles.
Comparator
There was no concurrent comparison group in the registry record. The study is identified as single-group, and allocation is listed as NA. Consequently, the record does not support a like-for-like comparison with another treatment or with a control group.
Primary question
The primary endpoint asks what percentage of participants had a complete or partial response under the revised National Cancer Institute-sponsored Working Group guidelines. Responses were assessed after 12 cycles, up to 48 weeks, with interim assessments after 3, 6 and 12 cycles. The response percentage itself is not reported in the registry record.
3. Trial Design
This was a phase 2, single-group study of lenalidomide plus rituximab for chronic lymphocytic leukemia or small lymphocytic lymphoma. The registry lists the study as completed and records enrollment as 60. That enrollment figure is not, by itself, a report of how many participants received treatment, completed all cycles, or contributed data to the primary endpoint; those analysis-population counts are not reported in the registry record.
Allocation is listed as NA, consistent with the single-group design. The registry identifies no randomized allocation or concurrent control group, so the study cannot estimate a treatment contrast against another assigned group. Masking is listed as none, meaning the record does not describe blinding. The sponsor is M.D. Anderson Cancer Center.
The treatment plan combined oral lenalidomide 10 mg/day, started on Day 9 of cycle 1, with intravenous rituximab. Rituximab was scheduled for Day 1, Day 8, Day 15 and Day 22, then once every four weeks during cycles 3-12 (+ 7 days); it was not given in Cycle 2. The intended treatment duration was twelve cycles. The registry does not report adherence, dose modifications, treatment discontinuations, or the number of cycles completed by participants.
The primary outcome was the percentage of participants with complete or partial response. The record specifies assessments after 12 cycles, up to 48 weeks, and interim assessments after 3, 6 and 12 cycles. These scheduled assessments describe when responses were assessed; they do not establish that formal interim statistical analyses were conducted. Any statistical interim-analysis plan is not reported in the registry record.
Because there is no comparator, the study design is suited to describing outcomes observed in the treated group, if those outcomes are reported. It does not, on its own, separate treatment effects from the course of the disease, other care, or differences between participants. Details of additional design procedures and the statistical plan 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: One of the 60 participants enrolled was excluded from the trial before any treatment assignment.
Overall Study
| Stage | Lenalidomide + Rituximab |
|---|---|
| STARTED | 59 |
| COMPLETED | 59 |
| NOT COMPLETED | 0 |
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 | Lenalidomide + Rituximab |
|---|---|---|
| Participants analysed | 59 | |
| Age, Continuous | years | 62 (42 to 82) |
| Sex: Female, Male: Female | Participants | 13 |
| Sex: Female, Male: Male | Participants | 46 |
| Region of Enrollment: United States | participants | 59 |
6. Primary Endpoint
The registry lists the primary outcome as Overall Participant Response Rate: Percentage of Participants With Complete + Partial Response According to Revised National Cancer Institute-sponsored Working Group Guidelines, measured over Responses assessed after 12 cycles, up to 48 weeks with interim assessments performed after 3, 6 and 12 cycles..
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | Percentage of Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the percentage of participants whose response was classified as complete or partial according to revised National Cancer Institute-sponsored Working Group guidelines. It is a binary outcome at the participant level: each assessed participant is classified by whether the response criteria were met, and the endpoint expresses the proportion classified as responders. A percentage is useful for presenting a clinically interpretable summary of response in a single-group study, while a count and a measure of uncertainty would help readers judge how precisely that percentage is estimated.
The criteria use clinical findings and blood and marrow measures. Complete response requires, among other criteria, absence of lymphadenopathy, hepatomegaly or splenomegaly and constitutional symptoms; a normal complete blood count, including polymorphonuclear leukocytes >1500/µL, platelets >100,000/µL and hemoglobin >11.0 g/dL (untransfused); a lymphocyte count <5,000/µL; and specified bone marrow findings. The description also treats persistent treatment-related cytopenia and bone marrow lymphoid nodules in an otherwise complete response as partial response.
Partial response requires specified reductions in peripheral lymphocytes, lymphadenopathy, and/or splenomegaly or hepatomegaly, along with improvement in at least one listed blood measure. The endpoint therefore combines response categories rather than reporting complete response alone. The primary response percentage and its uncertainty are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a response endpoint but does not report its observed result. It gives no primary response percentage, responder count, confidence interval, or statistical test result. Therefore, the record does not establish how many participants had a complete or partial response, nor how precisely a response percentage was estimated. No conclusion about the observed response rate can be drawn from the endpoint description alone.
The study has a single treatment group and no concurrent comparator. If a response result were available, it would describe responses recorded among participants in that group under the stated criteria. It would not directly quantify how responses differed from those under another treatment, because no such comparison group is identified. This is an important distinction between reporting an outcome in a treated group and estimating a comparative treatment effect.
The record lists enrollment as 60. This should not be read as the denominator for the primary response endpoint: the number assessed for response, the number included in the analysis, and the handling of participants with missing assessments are not reported in the registry record. Without those details, the relationship between the enrolled population and any potential endpoint estimate cannot be evaluated.
The timing of assessment is described as after 12 cycles, up to 48 weeks, with interim assessments after 3, 6 and 12 cycles. The record does not report which assessment posted the primary response result or whether response status was confirmed at a later assessment. It also does not state whether participants who discontinued treatment or lacked an assessment were counted as nonresponders, excluded, or handled in another way.
Safety information is reported separately. The registry lists 59 at risk and 29 affected for serious adverse events in the lenalidomide-plus-rituximab group. It also lists serious-event terms with percentages, including lung infection at 15.3% and neutropenic fever at 11.9%. These figures describe the registry's safety entries; they do not supply the missing response result, establish a comparison of risks, or indicate how events were attributed to treatment. The denominator and detailed event-counting rules for the listed terms are not reported in the registry record.
Overall, the available record characterizes the treatment schedule, the intended response definition, and selected safety summaries. Its missing primary response result and analysis details limit statistical interpretation. The record does not provide enough information to evaluate the precision of response estimation, to judge missing-data effects, or to compare this regimen with an alternative.
9. Statistical Methods Explained
A binary response endpoint classifies each participant as meeting or not meeting the response definition at the relevant assessment. A group response percentage is a proportion: the number classified as responders in the analysis divided by the number included in that analysis. The registry record names the endpoint as a percentage, but does not report the responder count, the analyzed denominator, or the resulting percentage. Thus, the endpoint definition is available, but the estimate is not.
What does a confidence interval add?
In general, a confidence interval conveys the uncertainty associated with an estimated quantity. For a response proportion, it would indicate a range of values compatible with the observed data under the interval's statistical assumptions. Its width depends on factors such as the number of assessed participants and the observed response proportion. A confidence interval is not a guarantee that the true value lies within its limits, and it does not address biases caused by missing outcome data or an unrepresentative study group. No interval for the primary response endpoint is reported in the registry record.
What does the single-group design allow?
In general, a single-group study can describe outcomes observed among participants receiving the study treatment. It does not contain a concurrent randomized comparison from which to estimate a between-group difference. Natural variation in disease course, participant characteristics, other care, and study conduct can affect outcomes. Without a comparison group, these influences cannot be separated from the treatment group's observed outcomes by a randomized contrast. In this study, allocation is listed as NA and the model is identified as single-group; the record does not describe a like-for-like control group.
How should the response criteria be understood?
The endpoint combines complete and partial response under the stated revised National Cancer Institute-sponsored Working Group guidelines. The criteria draw on several types of information, including clinical findings, blood counts, lymphocyte levels, and bone marrow findings. Complete response includes thresholds such as polymorphonuclear leukocytes >1500/µL, platelets >100,000/µL, hemoglobin >11.0 g/dL (untransfused), and lymphocyte count <5,000/µL, along with the other specified findings. Partial response requires the stated reductions in disease measures and improvement in at least one listed blood measure. Combining complete and partial response yields a broader response endpoint than either category alone. The record does not report category-specific counts.
What is known about statistical testing?
The registry record lists no analyses for the primary outcome. It does not report a hypothesis test, p-value, confidence interval, adjustment method, or statistical model for the response endpoint. Scheduled assessments after 3, 6 and 12 cycles are not evidence, by themselves, of formal interim statistical testing. An interim-analysis plan is not reported in the registry record.
General statistical practice distinguishes a planned assessment schedule from an interim analysis that could affect decisions about continuing a study or interpreting its final result. The latter requires details such as the analysis timing, decision rules, and any adjustment to preserve the intended error rate. Those details are not reported in the registry record and should not be inferred from the assessment schedule.
How do planning illustrations differ from observed results?
In general, a sample-size calculation estimates how many participants might be needed under specified assumptions to detect a chosen effect with a chosen power and significance level. It is a planning exercise, not an observed outcome and not a measure of the probability that a study's conclusion is correct. The assumptions recorded for a planning illustration describe a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with effects defined as fractions of an observed effect. These assumptions do not describe this trial's single-group allocation. No calculated planning values are reported in the registry record, and the missing primary response estimate means that the stated observed-effect basis cannot be evaluated from this record.
Any recalculation from posted summary statistics would be an unadjusted re-calculation and would not replace the sponsor's own analysis. In this record, no primary-outcome analysis or response summary is reported, so there is no stated response estimate to reproduce. The registry record also does not describe whether an analysis plan specified covariate adjustment or other modeling choices.
What limits reproducibility?
Reproducing a response analysis generally requires a defined analysis population, a response-assessment time point, a rule for participants without an assessment, and a stated method for estimating uncertainty. The record describes the endpoint criteria and assessment schedule, but does not report those analysis details or the data needed to reproduce an estimate. As a result, the endpoint can be understood conceptually, but its statistical result cannot be independently checked using the registry record.
10. Exact Estimates for Each Arm
No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.
| Arm | Participants | Events | Observed % | Clopper-Pearson 95% CI | Wilson 95% CI | Bayesian 95% credible interval |
|---|---|---|---|---|---|---|
| Lenalidomide + Rituximab | 59 | 39 | 66.1% | 52.6% to 77.9% | 53.4% to 76.9% | 53.3% to 76.9% |
R code and output
arm <- c("Lenalidomide + Rituximab")
n <- c(59)
events <- c(39)
for (i in seq_along(n)) {
ci <- binom.test(events[i], n[i])$conf.int # Clopper-Pearson exact interval
cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i]) # Bayesian, uniform Beta(1,1) prior
wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}
ARM Lenalidomide + Rituximab 59 39 66.1 52.6 77.9 53.4 76.9 53.3 76.911. Multiplicity, Missing Data and Analysis Populations
The primary endpoint has a stated response definition and assessment schedule, but the registry record does not report a statistical analysis of it. It also does not describe a plan for controlling multiplicity across outcomes, response categories, assessment times, or any other analyses. The presence of assessments after 3, 6 and 12 cycles does not establish that each assessment was tested statistically, or that any multiplicity adjustment was used. The statistical plan for such decisions is not reported in the registry record.
Missing-data handling is also not reported. The registry does not state how participants without an evaluable response assessment were treated, whether treatment discontinuation affected endpoint inclusion, or whether any imputation or sensitivity analysis was used. These choices can affect a binary response estimate: excluding participants without assessments can yield a different analyzed group from counting them as nonresponders. This is a general statistical issue, not a claim about what occurred in this study.
The record lists enrollment as 60, but does not report the number included in the primary endpoint analysis or give a participant flow from enrollment through assessment. It does not identify an intention-to-treat, per-protocol, or other analysis population. Nor does it report baseline characteristics for those analyzed or excluded. These gaps prevent a reader from determining exactly to whom a response estimate would apply, even if the estimate were available.
Because no response count or result is reported, it is not possible to assess how missing assessments may have influenced the endpoint estimate. The analysis population, multiplicity strategy, and missing-data methods are not reported in the registry record.
12. 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 |
|---|---|---|---|
| Lenalidomide + Rituximab | 29 | 59 | 49.2% |
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 |
|---|---|
| Lenalidomide + Rituximab | 59 of 59 |
Most frequent serious adverse event terms
| Event term | Organ system | Lenalidomide + Rituximab |
|---|---|---|
| Lung Infection | Infections and infestations | 9 of 59 |
| Neutropenic fever | Infections and infestations | 7 of 59 |
| Secondary malignancy | Neoplasms benign, malignant and unspecified (incl cysts and polyps) | 3 of 59 |
| Atrial Fibrillation | Cardiac disorders | 2 of 59 |
| Death | General disorders | 2 of 59 |
| Fever | General disorders | 2 of 59 |
| Skin infection | Infections and infestations | 2 of 59 |
| Enteritis | Infections and infestations | 2 of 59 |
| Acute Myocardial Infarction | Cardiac disorders | 1 of 59 |
| Cardiac arrhythmia | Cardiac disorders | 1 of 59 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Lenalidomide + Rituximab |
|---|---|---|
| Neutropenia | Blood and lymphatic system disorders | 43 of 59 |
| fatigue | General disorders | 32 of 59 |
| Diarrhea | Gastrointestinal disorders | 21 of 59 |
| Thrombocytopenia | Blood and lymphatic system disorders | 20 of 59 |
| Tumor flare | General disorders | 16 of 59 |
| Sensory neuropathy | Nervous system disorders | 14 of 59 |
| Rash | Skin and subcutaneous tissue disorders | 13 of 59 |
| Constipation | Gastrointestinal disorders | 11 of 59 |
| Nausea | Gastrointestinal disorders | 10 of 59 |
| Neurologic other | Nervous system disorders | 10 of 59 |
Serious events with the highest arm-level rate: lung infection (15.3%), neutropenic fever (11.9%), secondary malignancy (5.1%), atrial fibrillation (3.4%), death (3.4%).
The registry lists 59 participants at risk and 29 affected for serious adverse events in the lenalidomide-plus-rituximab group. This is the group-level safety summary in the record; it should not be interpreted as a comparison with an untreated or alternative-treatment group, because no such group is identified. The record also lists serious-event terms with percentages: lung infection, 15.3%; neutropenic fever, 11.9%; secondary malignancy, 5.1%; atrial fibrillation, 3.4%; death, 3.4%; and fever, 3.4%.
These term percentages should be read as registry-reported safety summaries, not as proof that the treatment caused the events. The denominator and detailed rules for counting participants or repeated events for each term are not reported in the registry record. The record does not provide event timing, severity grades, duration, outcomes, or attribution details for these listed terms. A listed term of death is not accompanied by a reported death count in the group summary. The serious-event figures also do not replace the missing primary response analysis.
13. What the Result Does, and Does Not, Mean
The record establishes that this was a completed phase 2, single-group study of lenalidomide plus rituximab in patients with chronic lymphocytic leukemia or small lymphocytic lymphoma who had already received therapy. It describes the dosing schedule, the combined complete-or-partial-response endpoint, the criteria used to classify response, and selected serious adverse event summaries. It does not report the primary response result.
Without the response count, percentage, or an uncertainty interval, the primary endpoint cannot be interpreted as an estimate of response frequency. The registry's enrollment figure of 60 is not a substitute for the denominator of an endpoint analysis. The number assessed, the number included in the analysis, and the handling of missing assessments are not reported. No conclusion about response precision can therefore be drawn from the record.
The single-group design also limits what a response result could establish. A response percentage in this group would describe outcomes under the study's assessment criteria, but would not provide a randomized comparison with another treatment. Differences from outcomes in another setting could reflect differences in participants, disease characteristics, follow-up, assessment, or care, rather than treatment alone.
The reported serious adverse event terms provide a safety description, but the record does not state the detailed denominator or event-counting rules for each term. They cannot establish causation or comparative safety. The figures should be interpreted alongside the limitations in reporting, not as a complete account of all harms or as a treatment comparison.
In general, a registry record is most informative when it reports outcomes together with the analyzed population, missing-data rules, statistical methods, and uncertainty. Those elements are not reported for the primary response endpoint in this record. Accordingly, the record describes the study question and design, but does not provide the result needed to quantify the primary response outcome or support a comparative conclusion.
14. Why This Trial Matters Statistically
This study illustrates why the distinction between an endpoint definition and an endpoint result matters. The registry describes a specific combined response outcome and detailed criteria for complete and partial response. Yet it does not report the resulting response percentage, responder count, or measure of uncertainty. A clearly defined outcome is necessary for interpretation, but it cannot substitute for reporting the observed data.
The single-group structure is also central to statistical interpretation. An outcome in a treatment group may be useful as a description of what was observed in that group, but it does not estimate a randomized treatment contrast. Readers need the design context before interpreting any percentage or safety summary. The registry identifies a single-group study with allocation listed as NA, so a like-for-like control comparison is not available.
The record also demonstrates why enrollment and analysis denominators should not be conflated. Enrollment is listed as 60, while the number assessed for the primary outcome and the analysis population are not reported. A response estimate requires a clear denominator and a transparent account of missing assessments. Without these details, its scope and precision would remain uncertain even if a percentage were reported.
Finally, assessment timing and analysis timing are different concepts. Assessments are specified after 3, 6 and 12 cycles, but the record does not describe a formal interim statistical plan. Statistical reporting should make clear which assessments support the primary result and how repeated looks or multiple outcomes are handled. Such reporting is not available in the registry record. These distinctions help readers separate what the study planned to measure from what can be learned from the posted results.
15. 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 record constrain interpretation. The primary endpoint is defined, including complete and partial response criteria, but its observed result is not reported. There is no response count, percentage, confidence interval, or statistical test result. The registry also does not report the number of participants assessed for response or the population included in the analysis.
The study is identified as single-group, with allocation listed as NA and no like-for-like control group. Consequently, the design does not provide a randomized comparative estimate. Masking is listed as none; the record does not describe blinded response assessment. Whether assessment procedures included other safeguards against bias is not reported in the registry record.
The enrollment figure does not establish how many participants began treatment, completed the intended twelve cycles, or had evaluable endpoint data. Participant flow, dose modifications, discontinuations, and reasons for missing assessments are not reported. Neither the analysis population nor the rules for handling missing response data are stated. This prevents evaluation of potential selection or missing-data effects.
The registry gives the timing of response assessments, but does not report which assessment defined the primary result, whether a response needed confirmation, or a statistical interim-analysis plan. Multiplicity procedures, covariate adjustment, and the endpoint's uncertainty method are also not reported. The safety record lists serious adverse event summaries, but detailed event-counting rules and denominators for the term percentages are not reported.
These limitations concern what can be concluded from the registry record; they do not establish that unreported procedures were or were not used. Additional statistical and outcome details are not reported in the registry record.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Lenalidomide and Rituximab as Treatment of Chronic Lymphocytic Leukemia — NCT00759603.
- Registry record last updated 2015-08-27; status last verified 2015-07.
- Results first posted 2015-08-27.
- 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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19. Record Summary
NCT00759603 is a completed phase 2, single-group study of lenalidomide plus rituximab for chronic lymphocytic leukemia or small lymphocytic lymphoma in patients who had already received therapy. The registry lists enrollment as 60, allocation as NA, and masking as none.
The primary endpoint is the percentage of participants with complete or partial response under revised National Cancer Institute-sponsored Working Group guidelines. Assessments were scheduled after 12 cycles, up to 48 weeks, with interim assessments after 3, 6 and 12 cycles. The primary response result and its statistical analysis are not reported in the registry record.
The safety summary lists 59 at risk and 29 affected for serious adverse events, along with percentages for selected serious-event terms. The record does not identify a concurrent comparison group or report the analysis population, missing-data approach, or statistical plan.