A Study of PCI-32765 (Ibrutinib) Versus Rituximab in Relapsed or Refractory Chronic Leukemia/Lymphoma: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study of PCI-32765 (Ibrutinib) Versus Rituximab in Relapsed or Refractory Chronic Leukemia/Lymphoma (NCT01973387), a randomized phase 3 study. The primary outcome is Progression-free Survival (PFS).

2. Clinical Question

3. Trial Design

This was a randomized, parallel-group, open-label phase 3 study sponsored by Janssen Research & Development, LLC. The registry record lists 160 participants as enrolled. The study compared ibrutinib with rituximab in adults in the Asia Pacific region with relapsed or refractory CLL or SLL. Participants were assigned to one of the two treatments, and the primary analysis was described as intent-to-treat: participants were analyzed according to their randomized group, irrespective of the treatment actually received.

The registry lists 106 participants in the ibrutinib group and 54 in the rituximab group for the primary outcome. The record describes no masking, so participants and study personnel were not blinded to assigned treatment. It does not report the method used to generate the random allocation sequence, how allocation was concealed, or the reasons for the unequal group sizes. It also does not provide arm-specific treatment details in the arm descriptions.

The study started on 2013-10-28, had a primary completion date of 2015-12-01, and is listed as completed. The primary outcome was progression-free survival, defined as time from randomization to disease progression or death, whichever was first reported. The stated observation period was up to 3.7 years. The record also lists secondary outcomes concerning overall response rate, overall survival, sustained hematologic improvement, and clinically relevant shifts in disease-related symptoms. Numeric results are not reported in the registry record for all of those listed outcomes.

The registry record does not report the original sample-size justification, the planned allocation ratio, or a detailed analysis plan. It also does not report whether interim analyses were planned or conducted. Those details cannot be inferred from the enrollment count or from the planning illustrations accompanying the posted results.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Intent-to-Treat (ITT) analysis set is defined as all participants randomized into the study and analyzed according to assigned treatment group, regardless of the actual treatment received.

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 Progression-free Survival (PFS), measured over From the date of randomization to the date of disease progression or death, whichever was first reported (Up to 3.7 years).

Progression-free survival measures the time from randomization until disease progression or death, whichever is reported first. In this study, progression was assessed using International Workshop on Chronic Lymphocytic Leukemia 2008 criteria. Those criteria include changes such as new or enlarged disease sites, increases in lymphocyte counts, and certain new blood-count abnormalities attributed to CLL. The registry definition also mentions transformation to a more aggressive histology.

This endpoint combines progression and death into a time-to-event outcome. It therefore reflects how long participants remain alive without a recorded progression, rather than counting only whether progression occurred by a single fixed visit. Time-to-event methods can account for participants whose follow-up ends before an event is recorded, provided appropriate censoring information and assumptions are used. The registry record does not report the detailed censoring rules or how incomplete assessments were handled.

The reported median is the time by which half of the analyzed group is estimated to have experienced the event, under the time-to-event analysis. A hazard ratio compares event rates over follow-up between groups; it is not a ratio of medians and does not directly state how many months an individual participant may remain progression-free. For the primary outcome, the record reports the rituximab median as 8.38 months, with a 95% confidence interval from 8.31 to 9.03 months. The ibrutinib median is not reported in the registry record, so the posted hazard ratio is the available comparative summary.

7. Results Posted in the Registry

• Ibrutinib vs Rituximab: hazard ratio 0.18 (95% CI 0.11–0.29), reported p < 0.001 (as reported in the registry).

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Overall Response Rate (ORR)

• Endpoint type: Binary: the number of participants with the event, compared as proportions.
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • Rituximab: 7.4% (4/54) versus 62.3% (66/106) on control; risk difference -54.9 percentage points (95% CI -66.4 to -43.3), risk ratio 0.12 (0.05–0.31); unadjusted two-proportion z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the proportion with the event is statistically lower for Rituximab than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The registry record lists overall response rate, overall survival, sustained hematologic improvement, and clinically relevant shifts in disease-related symptoms as secondary outcomes. Numeric results are posted for overall response rate, but the other listed outcomes are not reported in the registry record in the results available. Consequently, the secondary evidence is incomplete and does not provide a broad, fully reported profile across all listed outcomes.

The overall response rate counts show a higher number of recorded responses in the ibrutinib group than in the rituximab group. This broad pattern is directionally consistent with the primary progression-free survival comparison, but the outcomes measure different aspects of disease and are analyzed differently. Agreement in direction does not make them interchangeable, nor does it independently validate the primary analysis.

The secondary comparison is an unadjusted re-calculation, and no sponsor-reported inferential analysis for it is listed. A nominal statistical result for a secondary outcome should be interpreted more cautiously than a primary result when the record does not report how many outcomes were tested or whether multiplicity was addressed. When multiple outcomes are examined, the chance of at least one apparently notable finding can increase. This is a general statistical concern, not evidence that a particular adjustment was or was not applied in an unreported analysis.

Because results for overall survival, sustained hematologic improvement, and symptom shifts are not reported in the registry record, no conclusions about their comparative patterns can be drawn from these entries. The secondary material adds a limited descriptive perspective but cannot fill in missing outcome results or establish that the primary comparison translates into the same pattern for every other measure.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Overall Response Rate (ORR)
• Overall Survival (OS)
• Number of Participants With Sustained Hematologic Improvement
• Number of Participants With Clinically Relevant Shifts in Disease-Related Symptoms

9. Statistical Interpretation

10. Statistical Methods Explained

The primary outcome is a time-to-event measure. For each participant, the event is the first recorded progression or death. Time begins at randomization, so the comparison follows participants from a common study starting point rather than from the date treatment happened to begin. The record specifies International Workshop on Chronic Lymphocytic Leukemia 2008 criteria for defining progression. It does not report further operational details, such as how assessments were scheduled or how events were reviewed.

What does the hazard ratio describe?

A hazard is the event rate at a particular point in follow-up among participants who have not yet had an event. A hazard ratio compares that rate between groups over time. The reported hazard ratio of 0.178 is for ibrutinib versus rituximab. An estimate below 1 points toward a lower event hazard for the first group in that comparison. It is a relative measure, not a probability, a percentage reduction calculated for an individual, or a difference in median survival time.

Interpreting one hazard ratio as a single summary assumes that it is a useful description of the relative hazards over the analyzed follow-up. If the relative hazards change substantially over time, one constant summary may conceal that pattern. The registry record reports the hazard ratio and the log-rank method but does not report a proportional-hazards assessment or time-varying estimates. It is therefore not possible to assess those features from the posted information alone.

What does the log-rank method contribute?

The log-rank method compares the event experience of groups across the follow-up period, using the timing of events and the participants still at risk at each event time. It is commonly used for time-to-event comparisons and is the method identified for the reported hazard ratio. The method does not turn a time-to-event comparison into a direct measure of absolute time gained. Interpretation also depends on how follow-up and censoring are handled. Detailed censoring rules and the number of participants censored are not reported in the registry record.

The reported primary result is a sponsor analysis, rather than a separate unadjusted re-calculation based on summary counts. A hazard ratio cannot be reconstructed reliably from group totals alone because the event times and censoring information matter. The registry record lists a median for the rituximab group but no median for the ibrutinib group. Neither the missing median nor the underlying event-time curve can be inferred from the hazard ratio.

How should the confidence interval be read?

A confidence interval describes uncertainty in an estimated quantity under the statistical method used. For the primary hazard ratio, the 95% confidence interval is 0.109 to 0.291. The interval gives a range of values compatible with the observed data and model at the stated confidence level; it is not a range containing 95% of individual participant outcomes. Its position below 1 is consistent with the direction of the reported comparison. The interval does not account for uncertainties that are not represented in the analysis, such as possible outcome-assessment bias or unreported design limitations.

The p-value, reported as p < 0.001, addresses a different question from the confidence interval. It quantifies how incompatible the observed result is with a null comparison under the test's assumptions. It is not the probability that the null hypothesis is true, and it does not measure the magnitude of the treatment contrast. The estimate and interval are needed to understand both direction and precision.

Why can over-dispersion matter?

General explanation: over-dispersion arises when observed variability is greater than a statistical model expects. It can make standard errors too small if the model does not allow for the extra variation, making confidence intervals appear narrower and tests more optimistic than warranted. The primary endpoint is time-to-event, and the registry record identifies a log-rank analysis; it does not report an over-dispersion assessment. This concept is not a reported finding of this trial.

How do the secondary calculations differ?

The overall response rate is a binary outcome: each participant is classified according to whether a response was recorded. The posted secondary comparison includes an unadjusted re-calculation based on the group counts. Such a calculation is a simple comparison of the posted summaries and does not reproduce a fuller sponsor model if one exists. No sponsor-reported inferential analysis for this secondary result is listed in the registry record. The re-calculation is therefore useful as a descriptive statistical check, not as a replacement for a prespecified sponsor analysis.

For binary outcomes, a risk difference expresses the difference in the proportions with the outcome between groups; a confidence interval describes uncertainty around that difference. A relative risk or odds ratio expresses the comparison on a relative scale, and these measures are not interchangeable. The choice of scale affects how a result is expressed, not the underlying observed group counts. The posted secondary material includes several such comparison measures, but the record does not state that a multiplicity adjustment was used.

The primary hazard-ratio analysis and the secondary binary calculation answer different statistical questions and use different data structures. One uses event timing and censoring over follow-up; the other compares counts classified as responses. Their numerical estimates should not be directly compared as if they shared a common scale. The registry record does not report further sensitivity analyses, adjusted secondary models, or methods for handling missing response classifications.

11. Confidence Intervals and Precision

The primary hazard ratio is 0.178, with a 95% confidence interval from 0.109 to 0.291. The interval conveys uncertainty in the relative hazard estimate under the reported analysis. Because the full interval is below 1, the reported result is compatible with a lower event hazard in the ibrutinib group than in the rituximab group under that analysis. The range remains important: the point estimate alone is not the only plausible value supported by the data.

The confidence interval for the rituximab median progression-free survival is 8.31 to 9.03 months around the reported median of 8.38 months. The ibrutinib median and its confidence interval are not reported in the registry record. That absence prevents a direct comparison of the two medians from the posted results; it does not alter what the reported hazard ratio estimates.

In general, a confidence interval reflects the statistical uncertainty of an estimate under the chosen method and its assumptions. It does not include every possible source of uncertainty. For example, it cannot by itself resolve concerns about open-label assessment, incomplete reporting, or the applicability of the study population to other settings. Nor does it mean that individual participants' outcomes lie within the interval.

The precision of a time-to-event estimate is influenced by the amount and timing of event information, not only by the total number enrolled. The registry record does not report the total number of primary events or enough detail to assess the amount of censoring. The interval can therefore be described as posted, but its width cannot be independently audited from the information in the record.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The planning illustrations use different units for the two kinds of outcome. For progression-free survival, the entries are total events across both groups, not participants per arm. For the binary overall response rate, the entries are participants per arm. The values are illustrations based on the observed effect, not the original design calculations for this trial.

The stated planning assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The effect to detect is set to the stated fraction of the observed effect. For the time-to-event illustration, the total event counts are calculated using the Schoenfeld approach. The registry record does not report the trial's own original sample-size assumptions or justification, so these illustrations should not be read as a description of how the actual enrollment target was chosen.

The 80% power column represents the planned event or participant count for a hypothetical study with an 80% chance of detecting the specified effect under those assumptions, if that effect is real. The 90% power column gives the corresponding count for a hypothetical study with a 90% chance. Higher planned power generally requires more information, represented by events or participants, under otherwise unchanged assumptions.

Rows that use a smaller fraction of the observed effect require larger planned counts. That is because a smaller difference is harder to distinguish from random variation with the same level of certainty. These are prospective planning illustrations based on chosen assumptions and an observed effect estimate; they are not observed power. They do not establish that the completed trial had a particular probability of success or that its original design was adequately powered.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

d is the total number of events needed (Schoenfeld's formula) with 1:1 allocation and proportional hazards.

Worked calculation for this trial

1. Hazard ratio HR = 0.178, so ln(HR) = -1.7260.
2. d = 4 × (1.96 + 0.842)² / [ln(0.178)]² = 10.5, rounded up to 11 events in total for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
hr <- 0.178                              # observed hazard ratio
events_needed <- function(power, frac = 1) ceiling(round(4 * (z_a + qnorm(power))^2 / log(hr^frac)^2, 6))   # Schoenfeld, 1:1 allocation
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: events = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(events_needed(0.80, f), big.mark = ","), format(events_needed(0.90, f), big.mark = ",")))

# Simulation: given d total events under proportional hazards, events in the treatment arm are Binomial(d, hr / (1 + hr)).
# The score (log-rank type) statistic is (D1 - d / 2) / sqrt(d / 4).
set.seed(1973387)
d    <- events_needed(0.80)
reps <- 20000
D1 <- rbinom(reps, d, hr / (1 + hr))
z  <- (D1 - d / 2) / sqrt(d / 4)
cat(sprintf("Simulated power with %s events: %.3f (%d replicates)\n", format(d, big.mark = ","), mean(abs(z) > z_a), reps))

Output from running the code

100% of observed effect: events = 11 (80% power), 15 (90% power)
 75% of observed effect: events = 19 (80% power), 26 (90% power)
 50% of observed effect: events = 43 (80% power), 57 (90% power)
Simulated power with 11 events: 0.776 (20000 replicates)

The simulation uses the fact that, with d events in total and proportional hazards, the number of events in the treatment arm is binomial. It is an approximation that conditions on the total number of events, and it should land close to the target power.

14. Analyses Reported by the Sponsor

The primary hazard ratio and its confidence interval are the sponsor's reported analysis, using the log-rank method. The reported comparison is 0.178, with a 95% confidence interval of 0.109 to 0.291 and p < 0.001. No separate recalculated primary hazard ratio is presented. This is appropriate for a time-to-event endpoint, for which a valid re-analysis would require event-time and censoring data, not only the posted medians and group sizes.

The record does not flag a discrepancy between the sponsor analysis and a recalculation. There is therefore no conflicting primary estimate to reconcile. The sponsor's analysis remains the relevant reported inferential result for progression-free survival, while the median reported for rituximab is a separate descriptive summary. A corresponding ibrutinib median is not reported in the registry record.

For overall response rate, the posted material includes an unadjusted re-calculation from the group summaries, but no sponsor-reported inferential analysis is listed. That calculation should be understood as a straightforward comparison of the posted counts, not as evidence that the sponsor used the same method in a full analysis. The registry record does not report a sponsor model or multiplicity procedure for this secondary outcome.

15. Multiplicity, Missing Data and Analysis Populations

The registry record identifies progression-free survival as the primary outcome and lists several secondary outcomes. It does not report a multiplicity-control procedure, such as a testing hierarchy or adjustment of significance thresholds across outcomes. Without that information, the reported primary p-value can be read as the result for the stated primary comparison, but the status of any secondary p-values within a broader testing plan is unclear. This limitation is especially relevant because only an unadjusted re-calculation is available for the posted overall response rate comparison, while results for other listed secondary outcomes are not reported in the registry record.

The record defines the primary analysis population as all randomized participants, analyzed according to assigned group regardless of actual treatment received. This is an intent-to-treat approach and preserves the randomized assignment for the primary comparison. The registry record does not provide a detailed account of participant flow, exclusions from particular endpoint analyses, or the number of participants with evaluable data for every secondary outcome.

Handling of missing data is not reported in the registry record. For a time-to-event outcome, follow-up that ends before progression or death may be treated as censored, but the timing and assumptions used for censoring are not described. The record also does not report how missing or unevaluable response assessments were classified, whether sensitivity analyses were conducted, or how withdrawals were incorporated into each analysis. Those details matter because missing outcomes and follow-up patterns can affect both estimates and uncertainty.

The original sample-size justification, interim-analysis plan, and detailed statistical analysis plan are not reported in the registry record. It is therefore not possible to determine from these entries whether the trial's original design anticipated the observed event pattern, whether formal interim monitoring took place, or how the investigators planned to control type I error across outcomes. The posted planning illustrations are not a substitute for those protocol details.

16. 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 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: lung infection (11.5%), pyrexia (5.8%), pneumonia (4.8%), infection (3.8%), lymphadenitis (2.9%).

The safety entries report serious adverse events in 56 of 104 participants at risk in the ibrutinib group and 17 of 52 at risk in the rituximab group. Other adverse events are reported for 103 of 104 and 46 of 52 participants at risk, respectively. Deaths are reported for 21 participants in the ibrutinib group and 20 in the rituximab group. These are counts in the listed safety groups; the denominators differ from the primary intent-to-treat group sizes.

The most frequently listed serious adverse-event terms include lung infection at 11.5%, pyrexia at 5.8%, pneumonia at 4.8%, infection at 3.8%, lymphadenitis at 2.9%, and atrial fibrillation at 2.9%. These entries describe reported event terms and do not establish that an event was caused by treatment. The registry record does not provide the full event-level detail, exposure-adjusted rates, or further information about attribution and severity needed for a more complete comparative safety assessment.

Safety counts should be interpreted alongside the population at risk and the way events were collected. Counts alone do not account for differences in time on treatment or follow-up. These data describe the adverse-event information posted in the registry record and are not a basis for medical advice.

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

The primary result describes a statistically strong relative separation between the assigned groups in the reported progression-free survival analysis. The hazard ratio estimate is below 1 for ibrutinib versus rituximab, and its 95% confidence interval is also below 1. The log-rank p-value is reported as p < 0.001. These results indicate that the observed time-to-event data were inconsistent with a no-difference comparison under the analysis assumptions.

The result does not state how many additional months participants in one group remained progression-free. The registry reports a median for rituximab but not for ibrutinib, so the posted information does not support a direct comparison of median times. Nor does the hazard ratio tell the probability that a particular participant will experience progression or death by a specified time. It is a group-level relative measure across follow-up.

The trial was randomized, which supports interpretation of the comparison according to assigned treatment, and the stated primary population is intent-to-treat. The study was open-label, however, and details on outcome assessment, censoring, and missing data are not reported in the registry record. Those features limit how fully the analysis can be evaluated from the posted information. The result also pertains to the adults with relapsed or refractory CLL or SLL described in the study, in the Asia Pacific region, and does not automatically apply to other populations or settings.

The secondary evidence is less complete. The record lists several secondary outcomes, but numeric results are not reported for all of them, and the overall response rate comparison has no sponsor-reported inferential analysis listed. A directional pattern in that endpoint does not establish matching effects on survival, symptoms, or hematologic improvement.

Statistical evidence about a group comparison is not a guarantee of an outcome for an individual, and a small p-value does not by itself convey clinical importance. These results describe the posted analysis, not a recommendation about treatment. Questions about benefits and harms require a complete clinical assessment, including details not available in the registry record.

18. Why This Trial Matters Statistically

This study illustrates how randomized comparisons of time-to-event outcomes are reported and interpreted. The primary endpoint accounts for both disease progression and death and uses the time until the first of those events, rather than relying only on a fixed-time count. The hazard ratio gives a relative summary across follow-up, while the median is an absolute time summary. Seeing that the record reports the rituximab median but not the ibrutinib median makes clear why one statistic cannot substitute for the other.

The primary confidence interval and p-value also show why effect estimates should be considered together with uncertainty. The point estimate gives the reported direction and magnitude on the hazard-ratio scale, while the interval communicates a range of values compatible with the analysis. The p-value addresses evidence against a no-difference model, not the size of a difference or its importance to an individual.

The trial is also a useful example of the distinction between a sponsor-reported time-to-event analysis and a simple re-calculation from posted binary counts. Event times and censoring are essential to the primary analysis, whereas response counts permit a straightforward unadjusted secondary comparison. Different endpoints require different methods, and an unadjusted secondary result should not be treated as interchangeable with the primary analysis.

Finally, the registry record demonstrates why reporting completeness matters. It identifies the randomized design and intent-to-treat population, but does not report the original sample-size justification, detailed missing-data methods, or results for every listed secondary outcome. Statistical interpretation depends not only on the numerical estimate but also on knowing how the analysis was planned and carried out.

19. 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 trial-specific details needed to fully evaluate the primary result are not reported in the registry record. These include the ibrutinib median progression-free survival, the total number of primary events, the censoring rules, and the extent of missing endpoint data. The hazard ratio and its interval are available, but the underlying event-time distribution cannot be independently assessed from the posted summaries.

The study was open-label, and the registry record does not describe the procedures used to assess progression or whether outcome assessments were reviewed independently. Progression was defined using International Workshop on Chronic Lymphocytic Leukemia 2008 criteria, but details of assessment timing and event adjudication are not reported. The record also does not report the randomization sequence method or allocation concealment procedures.

The registry lists secondary outcomes beyond overall response rate, but numeric results for the other listed outcomes are not reported in the registry record. It does not describe a multiplicity plan or a detailed statistical analysis plan. The overall response rate result has an unadjusted re-calculation but no sponsor-reported inferential analysis listed, limiting comparison with the sponsor's primary analysis.

The record does not report the original sample-size rationale, interim-analysis details, treatment schedules, or full safety-event information. The safety entries have group-specific denominators that differ from those used for the primary outcome, and the posted counts do not provide exposure-adjusted comparisons. These gaps restrict assessment of the design rationale, robustness, and full balance of benefits and harms from the registry information alone.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: A Study of PCI-32765 (Ibrutinib) Versus Rituximab in Relapsed or Refractory Chronic Leukemia/Lymphoma — NCT01973387.
• Registry record last updated 2018-07-24; status last verified 2018-06.
• Results first posted 2017-02-23.
• 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.

23. Record Summary

The registry record describes a completed randomized, open-label, parallel-group phase 3 study of ibrutinib versus rituximab in adults in the Asia Pacific region with relapsed or refractory CLL or SLL. It lists 160 participants enrolled and defines the primary analysis population as all randomized participants analyzed according to assigned treatment.

The primary outcome was progression-free survival from randomization to progression or death. The reported hazard ratio for ibrutinib versus rituximab was 0.178, with a 95% confidence interval from 0.109 to 0.291 and p < 0.001. A median of 8.38 months is reported for rituximab; an ibrutinib median is not reported in the registry record. The record lists several secondary outcomes, but numeric results are not reported for all of them.