Ibrutinib After Intensive Induction in Treating Patients With Previously Untreated Mantle Cell Lymphoma: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Ibrutinib After Intensive Induction in Treating Patients With Previously Untreated Mantle Cell Lymphoma (NCT02242097), a na phase 2 study. The primary outcome is Determine the Progression-free Survival (PFS) Rate After 3 Years.

2. Clinical Question

3. Trial Design

This phase II study evaluated ibrutinib maintenance following intensive induction in patients with previously untreated mantle cell lymphoma. It was registered as a single-group study with no masking and no randomized allocation. The registry enrollment is 37. Because the study has no concurrent control group, its design can describe outcomes among participants receiving the study treatment but cannot provide a randomized estimate of the difference between ibrutinib and an alternative.

The intervention description specifies oral ibrutinib once daily on days 1–28, in repeating 28-day courses for up to 4 years. Treatment could stop in the event of disease progression, unacceptable toxicity, or patient preference. The record also lists laboratory biomarker analysis as an intervention category, but does not give its methods or results.

The study status is completed. The recorded start date is 2015-01-12 and the primary completion date is 2021-12-07. Those dates describe the registry timeline; they do not establish when every participant began or ended treatment. Participant-level treatment duration is not reported in the registry record.

The listed secondary outcomes include adverse events defined according to the National Cancer Institute’s Common Terminology Criteria for Adverse Events Version 4.0, conversion from partial response to complete response, and overall survival after 4 years. The registry indicates five outcome measures, but details for every measure are not reported. Statistical analysis entries 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.

Ibrutinib Treatment

Reasons for not completing this period:

Post Therapy Follow Up

Reasons for not completing this period:

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.

6. Primary Endpoint

The registry lists the primary outcome as Determine the Progression-free Survival (PFS) Rate After 3 Years, measured over Assessed at 3 years.

The primary endpoint is the progression-free survival rate assessed at 3 years. Progression-free survival is a time-to-event outcome: it concerns how long participants remain alive without documented disease progression. The record defines the measurement period as starting at the start of treatment and ending at progression. For participants with measurable disease, clinical progression was to be documented by imaging with a CT scan. The stated progression criteria use the LUGANO Criteria: a Deauville score of 4 or 5, meaning increased uptake compared with baseline, or the appearance of new lesions.

A three-year rate expresses the proportion of participants estimated to remain free of the endpoint event through that time point. In general, such a rate can convey the overall outcome at a clinically specified time, while the time-to-event framework can account for differences in follow-up. Its interpretation depends on how events, censoring, and missing follow-up are handled. Those analysis details are not reported in the registry record.

The registry gives the endpoint definition and assessment time but does not report the observed three-year progression-free survival rate, its confidence interval, or the number of progression events. Without those results, the size and precision of the endpoint estimate cannot be described.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies a phase II single-group study with no masking and no randomized allocation. These design features determine what kinds of statistical conclusions the data can support. A single-group study can estimate outcomes among the people enrolled and treated, subject to follow-up and analysis choices. It does not create a concurrent group receiving a different strategy, so it cannot directly estimate a randomized between-group treatment effect.

What does a progression-free survival rate represent?

In general, progression-free survival is analyzed as a time-to-event outcome. Each participant contributes information from a defined starting point until progression or another event specified by the analysis. Participants without a recorded event by the end of their available follow-up may be censored: their observed time contributes information up to that point, but their later outcome is unknown. A time-to-event method can use these differing follow-up durations rather than treating every participant as if observed for the same length of time.

The registry sets the starting point at the start of treatment and identifies 3 years as the assessment time. It defines progression using the LUGANO Criteria, including a Deauville score of 4 or 5 or new lesions, and says CT imaging would document clinical progression for patients with measurable disease. The statistical method used to calculate the rate, the censoring rules, and the handling of deaths are not reported in the registry record. Those details matter because different endpoint and censoring rules can lead to different estimates.

Why does uncertainty matter?

In general, a point estimate alone does not show how much the result might vary because of sampling uncertainty. A confidence interval gives a range that reflects uncertainty under the selected model and assumptions. Its width depends on factors such as the amount of information available and the number and timing of observed events. The registry record does not report a primary endpoint estimate or confidence interval, so precision cannot be assessed.

Statistical significance and clinical importance are also different concepts. A test result addresses compatibility with a specified null hypothesis under a chosen model; it does not by itself establish the practical importance of an effect. No primary endpoint test, p-value, or analysis model is reported in the registry record. In a single-group study, a test against an external benchmark would require a stated benchmark and assumptions about its relevance; such details are not reported.

How should the safety counts be understood?

For binary outcomes, a count of participants with an event and a count at risk describe how often the event was recorded in the specified group. They do not by themselves describe event timing or duration. In general, one participant can experience more than one adverse event, so event-term counts and counts of affected participants are not interchangeable. The registry lists at-risk and affected counts for serious and other adverse events, but the precise analysis conventions and observation window are not reported.

Over-dispersion is a general issue when observed event counts vary more than a simple probability model would expect. It can arise, for example, when event rates differ across participants or events cluster within participants. Models that account for such extra variation can produce more appropriate uncertainty estimates than models that assume independent, identically distributed events. The registry does not report an over-dispersion model or any other statistical model for safety outcomes; no such method should be assumed.

What can a planning illustration tell the reader?

In general, a sample-size calculation describes how much information a hypothetical design might need under stated assumptions. It is a planning illustration, not evidence about the precision actually achieved in a completed study and not observed power. The registry’s planning assumptions describe a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect expressed as a fraction of the observed effect. Those assumptions do not describe this single-group trial’s allocation. Any illustration based on them should therefore not be interpreted as the trial’s own design or as a direct account of its achieved information.

The record does not report the trial’s own sample-size justification, statistical analysis plan, interim analyses, or analysis population definitions. These are distinct from general statistical principles and cannot be inferred from the phase, enrollment, or completion status.

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.

R code and output

arm    <- c("Treatment (Ibrutinib)")
n      <- c(36)
events <- c(34)
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  Treatment (Ibrutinib)  36  34  94.4  81.3  99.3  81.9  98.5  81.8  98.3

11. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary endpoint and several secondary outcomes, including adverse events, conversion from partial response to complete response, and overall survival after 4 years. It indicates five outcome measures in total, but details for every measure are not reported. The record does not describe a multiplicity strategy, such as adjusting the interpretation of statistical tests when several outcomes are examined. Without that information, it is not possible to determine whether or how the risk of false-positive findings across multiple tests was addressed.

Missing data and incomplete follow-up can affect time-to-event estimates. In general, censoring is appropriate when the analysis accounts for the time participants were observed and the assumptions about why follow-up ended are reasonable. If people who leave follow-up differ in their future risk from those who remain, an estimate may be affected. The registry record does not report the amount or pattern of missing follow-up, censoring rules, or sensitivity analyses.

The record also does not define the analysis populations, such as which enrolled participants were included in each outcome analysis, or how treatment discontinuation and protocol deviations were handled. It does not report the number included in the primary endpoint analysis. These omissions limit assessment of whether the analyzed group matches the enrolled group and how robust the findings would be to alternative analysis choices. No statistical analysis entries are reported in the registry record.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: atrial fibrillation (16.7%), lung infection (13.9%), pericardial effusion (5.6%), general disorders and administration site conditions - other, specify (5.6%), skin infection (5.6%).

The registry’s serious adverse event summary for the ibrutinib treatment group lists 36 participants at risk and 22 affected. For other adverse events, it lists 36 at risk and 36 affected. The summary also lists 4 deaths. These are descriptive counts as recorded; the registry does not provide enough detail to establish event attribution, timing, duration, or the relationship between the listed counts and treatment exposure.

The record identifies atrial fibrillation at 16.7% and lung infection at 13.9% among the leading serious adverse event terms. Pericardial effusion, general disorders and administration site conditions - Other, specify, skin infection, and neoplasms benign, malignant and unspecified (incl cysts and polyps) - Other, specify are each listed at 5.6%. These percentages are reported as registry values and should not be treated as incidence estimates with more precision than stated.

In general, an adverse event occurring during a study does not by itself establish that the study treatment caused it. A serious event is a classification of seriousness, not necessarily a judgment about causation. The registry’s listed safety counts do not provide a randomized comparison, and details of follow-up time and event-level analysis are not reported.

13. What the Result Does, and Does Not, Mean

The study addresses a defined clinical research question: the three-year progression-free survival rate after ibrutinib maintenance following induction chemotherapy for previously untreated mantle cell lymphoma. The registry specifies the endpoint timing and progression criteria, describes the treatment schedule, and records safety summaries. These features clarify what the trial was intended to evaluate.

However, the primary endpoint result is not reported in the registry record. There is no reported three-year rate, confidence interval, progression-event count, or statistical analysis result. The record therefore does not permit a quantitative description of the primary outcome’s magnitude or precision. Completion status indicates that the study is marked completed in the registry; it does not substitute for an outcome estimate.

The design also limits what can be concluded. Because the study used a single group without randomized allocation, its outcomes cannot establish how ibrutinib maintenance compares with another treatment or with no maintenance. General comparisons with other populations or historical results would depend on information and assumptions not reported in the registry record.

The safety counts and event terms are useful as descriptive records of what was reported for the study group. They do not, on their own, show that treatment caused an event or provide a controlled estimate of excess risk. The record does not report event timing, exposure-adjusted rates, or detailed attribution.

Accordingly, the registry entry supports an account of the study’s design, intended endpoint, intervention, and recorded safety summaries. It does not support a conclusion about the numerical progression-free survival result, comparative efficacy, or causal safety effects. Those questions require outcome and analysis information that is not reported in the registry record.

14. Why This Trial Matters Statistically

This trial is statistically informative as an example of how design determines the scope of inference. A single-group phase II study can describe outcomes in the treated group, but it does not provide a randomized control comparison. That distinction is especially important when interpreting a maintenance strategy after induction: the observed course of disease in the study group cannot by itself isolate the contribution of maintenance treatment from other explanations.

The endpoint is also explicitly time-based. Progression-free survival at 3 years depends not only on whether events occur, but on when they occur and how follow-up is handled. In general, time-to-event analysis can retain information from participants whose follow-up ends before the assessment time, but interpretation depends on censoring assumptions and endpoint rules. The registry gives progression criteria but does not report the analysis details or estimate.

The record illustrates why an endpoint definition and a result are different things. A precise definition makes the intended measurement understandable; without the observed estimate and its uncertainty, readers cannot evaluate its magnitude or precision. Similarly, safety counts help describe recorded events, but they do not establish causality or comparative risk in a study without a control group.

Finally, planning calculations should be distinguished from results. The registry’s stated planning assumptions describe a hypothetical two-arm calculation, whereas the trial itself is single-group. Such illustrations are not a substitute for the trial’s own design justification or for evidence about the information actually obtained. Those design and analysis details are not reported in the registry record.

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.

The central limitation of the registry record for statistical interpretation is that it does not report the primary endpoint result. No progression-free survival rate at 3 years, confidence interval, event count, or primary analysis model is given. Without these, readers cannot assess either the observed outcome or its precision.

The single-group design is a trial-level limitation for comparative inference. There is no randomized comparator, so the record cannot show what would have happened to a similar group receiving a different strategy. The study can describe outcomes in its treatment group, but a causal treatment contrast is not available from the design described.

Important analysis details are not reported in the registry record. These include the primary endpoint calculation method, censoring and missing-data rules, analysis populations, follow-up completeness, treatment exposure duration, and handling of participants who stopped treatment. The record also does not report the statistical analysis plan, sample-size justification, or interim analyses. Their absence from the record means these aspects cannot be evaluated; it does not establish what methods were or were not used outside the registry entry.

The registry reports safety counts and selected serious adverse event terms, but does not give a detailed event timeline or enough information to interpret the counts as exposure-adjusted rates. It also does not report results for all listed outcome measures. Finally, although the listed conditions include multiple disease stages, stage-specific enrollment and outcome summaries are not reported. This limits assessment of how outcomes may vary across the included disease stages.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Ibrutinib After Intensive Induction in Treating Patients With Previously Untreated Mantle Cell Lymphoma — NCT02242097.
• Registry record last updated 2026-06-10; status last verified 2026-05.
• Results first posted 2024-03-12.
• 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.

19. Record Summary

This is a completed phase II, single-group study of oral ibrutinib maintenance following intensive induction for previously untreated mantle cell lymphoma. Registry enrollment is 37. The intervention description specifies once-daily dosing on days 1–28 in repeating 28-day courses for up to 4 years, subject to progression, unacceptable toxicity, or patient preference.

The primary endpoint was progression-free survival at 3 years, measured from treatment start and defined using the LUGANO Criteria. Its result is not reported in the registry record. The registry lists secondary outcomes that include adverse events, response conversion, and overall survival after 4 years, as well as serious and other adverse event summaries. Statistical analysis details, primary endpoint precision, and results for all listed outcomes are not reported.