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 Veliparib, Bendamustine Hydrochloride, and Rituximab in Treating Patients With Relapsed or Refractory Lymphoma, Multiple Myeloma, or Solid Tumors (NCT01326702), a registered phase 1, phase 2 study. The primary outcome is Response Rate.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01326702 |
| Phase | Phase 1, Phase 2 |
| Condition | Adult B Acute Lymphoblastic Leukemia, Adult Nasal Type Extranodal NK/T-Cell Lymphoma, Adult Solid Neoplasm |
| Allocation | Not Stated |
| Design model | Sequential |
| Masking | None (open label) |
| Enrollment | 43 |
| Arms in the primary outcome | n/a |
| Lead sponsor | National Cancer Institute (NCI) |
| Results posted | Yes |
2. Clinical Question
Population
Patients with lymphoma, multiple myeloma, or solid tumors that had relapsed or were refractory to treatment. The registry lists a broad range of malignancy conditions; it does not give a single, narrower population description for the primary response endpoint.
Intervention
The study evaluated veliparib with bendamustine, with rituximab included in the study title and listed as an intervention. The treatment description specifies veliparib by mouth twice daily on days 1–7 and bendamustine by intravenous infusion on days 1–2, with treatment repeating every 28 days for up to 6 courses if there was no disease progression or unacceptable toxicity. The rituximab schedule is not reported in the registry record.
Comparator
No randomized control comparison is described. The registry lists sequential dose levels, and the allocation method is not stated. These dose groups should not be interpreted as like-for-like treatment and control arms.
Primary question
What response rate was observed with the study treatment, assessed using RECIST v1.0 criteria for target lesions and MRI and/or CT? The registry gives the endpoint definition and a timeframe of 2 years, but response results are not reported in the registry record.
The study addressed both dose and activity questions. Its phase 1b/2a designation and sequential model fit a study organized around escalating dose levels, while the registry describes response rate as the primary endpoint. The listed conditions span multiple lymphoma types, multiple myeloma, and solid neoplasms, so the endpoint concerns a clinically heterogeneous set of diseases rather than one clearly defined disease group.
The central statistical distinction is between estimating response in a treated study population and comparing treatment effects between groups. The record describes no randomized comparator, and it does not report a response count or response proportion. Consequently, the available registry information does not establish the magnitude or precision of response, nor does it support a causal comparison with another treatment. The enrollment is 43, but the registry record does not specify how many participants contributed to the primary endpoint analysis.
3. Trial Design
This was a completed phase 1b/2a study sponsored by the National Cancer Institute (NCI). The registry records a sequential model, no masking, enrollment of 43, a start date of 2011-07, and a primary completion date of 2015-04. The two listed phase categories are PHASE1 and PHASE2. The study title describes veliparib in combination with bendamustine, with or without rituximab, in lymphoma, multiple myeloma, and solid tumors.
The treatment description says that patients received veliparib by mouth twice daily on days 1–7 and bendamustine hydrochloride intravenously over 30–60 minutes on days 1–2. Courses repeated every 28 days for up to 6 courses in the absence of disease progression or unacceptable toxicity. The description begins to discuss a cohort after determination of the maximum-tolerated dose, but the remainder of that description is not reported in the registry record. The schedule and use of rituximab are not reported in the registry record.
The listed adverse-event groups correspond to Dose Levels 1 through 7, with different bendamustine and ABT-888 dose descriptions. The sequential model and these dose groups indicate that the record presents dose-level cohorts rather than randomized comparative arms. The allocation method is not stated. The registry itself cautions that the arms are not a like-for-like control comparison.
Enrollment is a registry figure and should not be assumed to equal the number included in every analysis. The analyzed population, the number assessed for response, and the handling of participants who did not complete treatment are not reported in the registry record. The registry lists secondary outcomes including complete response, duration of remission, overall survival, pharmacokinetic parameters, progression-free survival, and participants with dose-limiting toxicities. Results for these outcomes 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.
Only the first 6 of 7 groups are shown.
Overall Study
| Stage | Dose Level 1-Bendamustine 70 mg/m2, ABT-888 50 mg | Dose Level 2: Bendamustine 90 mg/m2, ABT-888 50 mg | Dose Level 3: Bendamustine 90 mg/m2, ABT-888 100 mg BID | Dose Level 4: Bendamustine 90 mg/m2, ABT-888 150 mg BID | Dose Level 5: Bendamustine 90 mg/m2, ABT-888 200 mg BID | Dose Level 6: Bendamustine 90 mg/m2, ABT-888 300 mg BID |
|---|---|---|---|---|---|---|
| STARTED | 3 | 3 | 6 | 4 | 5 | 15 |
| COMPLETED | 1 | 1 | 1 | 1 | 1 | 7 |
| NOT COMPLETED | 2 | 2 | 5 | 3 | 4 | 8 |
Reasons for not completing this period:
| Reason | Dose Level 1-Bendamustine 70 mg/m2, ABT-888 50 mg | Dose Level 2: Bendamustine 90 mg/m2, ABT-888 50 mg | Dose Level 3: Bendamustine 90 mg/m2, ABT-888 100 mg BID | Dose Level 4: Bendamustine 90 mg/m2, ABT-888 150 mg BID | Dose Level 5: Bendamustine 90 mg/m2, ABT-888 200 mg BID | Dose Level 6: Bendamustine 90 mg/m2, ABT-888 300 mg BID |
|---|---|---|---|---|---|---|
| Other | 1 | 0 | 0 | 0 | 0 | 1 |
| progressive disease | 1 | 1 | 3 | 1 | 3 | 2 |
| Death | 0 | 1 | 0 | 0 | 0 | 0 |
| Adverse Event | 0 | 0 | 1 | 1 | 0 | 3 |
| Withdrawal by Subject | 0 | 0 | 1 | 0 | 1 | 1 |
| Not Treated | 0 | 0 | 0 | 1 | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: The MTD was established at Dose Level 6 Veliparib 300mg PO BID plus Bendamustine 90 mg/m2
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.
Only the first 6 of 8 groups are shown.
| Characteristic | Unit | Dose Level 1: Bendamustine 70 mg/m2, ABT-888 50 mg | Dose Level 2: Bendamustine 90 mg/m2, ABT-888 50 mg | Dose Level 3: Bendamustine 90 mg/m2, ABT-888 100 mg BID | Dose Level 4: Bendamustine 90 mg/m2, ABT-888 150 mg BID | Dose Level 5: Bendamustine 90 mg/m2, ABT-888 200 mg BID | Dose Level 6: Bendamustine 90 mg/m2, ABT-888 300 mg BID |
|---|---|---|---|---|---|---|---|
| Participants analysed | 3 | 3 | 6 | 4 | 5 | 15 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 1 | 1 | 4 | 4 | 1 | 8 |
| Age, Categorical: >=65 years | Participants | 2 | 2 | 2 | 0 | 4 | 7 |
| Sex: Female, Male: Female | Participants | 1 | 2 | 5 | 2 | 2 | 8 |
| Sex: Female, Male: Male | Participants | 2 | 1 | 1 | 2 | 3 | 7 |
| Region of Enrollment: United States | participants | 3 | 3 | 6 | 4 | 5 | 15 |
6. Primary Endpoint
The registry lists the primary outcome as Response Rate, measured over 2 years.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is response rate, recorded as a count of participants, with a timeframe of 2 years. Its description uses Response Evaluation Criteria in Solid Tumors (RECIST) v1.0 for target lesions assessed by MRI and/or CT. The criteria distinguish partial response, stable disease, progression of disease, and complete response. A partial response requires a >=30% decrease in the sum of the longest diameters of target lesions. Stable disease is neither enough shrinkage to meet partial-response criteria nor enough increase to meet progression criteria. Progression includes a 20% increase in the sum of the longest diameters, a measurable increase in a non-target lesion, or the appearance of new lesions. Complete response is disappearance of all target lesions.
General: A response endpoint gives a structured way to describe tumor change against prespecified criteria. Using defined categories helps make assessment more consistent than relying on an informal judgment of improvement. It does not, by itself, show how long a response lasts or whether a treatment changes outcomes relative to a control group. Those questions require additional outcomes and an appropriate design.
The registry specifies a participant count as the measure but does not report the response count, the denominator assessed, or a response estimate. Therefore, the endpoint definition can be described, but the observed response rate and its precision cannot be characterized from the registry record. The registry lists duration of remission and other outcomes separately; their results are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies response rate as the primary endpoint, but it does not report the number of participants with a response, the number evaluated, an estimated response rate, or an uncertainty interval. The endpoint timeframe is 2 years. These omissions mean the primary efficacy result cannot be interpreted quantitatively from the registry information available. Enrollment of 43 is not a substitute for the analyzed denominator, and it does not establish that every enrolled participant was assessable for response.
The study is described as sequential and unmasked, with seven dose-level groups listed for safety. The record does not describe a randomized control group, and the allocation method is not stated. Thus, the dose groups do not support the same interpretation as concurrent randomized arms designed for a direct treatment comparison. Differences between cohorts could reflect their distinct dose levels or other features not reported in the registry record. The record does not supply a comparative effect estimate.
The serious adverse-event counts vary across the listed dose groups. For example, the record reports 1 affected participant among 3 at risk at Dose Level 1, 3 among 3 at Dose Level 2, and 5 among 15 at Dose Level 6. These are descriptive counts within the dose groups, not estimates of comparative risk. The registry lists 1 death at Dose Level 2 and 0 deaths in each other listed group. The record does not state whether reported events were judged related to treatment, nor does it provide enough detail to interpret event timing, recurrence, or participant-level overlap. The listed non-serious-event counts likewise should be read as group-specific descriptions, not as evidence of comparative safety.
General: A confidence interval expresses the range of values compatible with an estimate under a statistical model and sampling assumptions. It helps convey precision, which is especially important when groups are small. No confidence interval for the primary response outcome is reported in the registry record, so the precision of the response estimate cannot be assessed.
The listed secondary outcomes would address other dimensions of activity, safety, and drug exposure, but their results are not reported in the registry record. Overall survival, progression-free survival, and duration of remission are time-to-event outcomes; their interpretation depends on follow-up and event information. Those details, along with the statistical methods used to analyze them, are not reported in the registry record. As a result, no efficacy conclusion or comparison between dose levels can be drawn from these registry entries alone.
9. Statistical Methods Explained
What can be read from the design? The record identifies a sequential model, no masking, phase 1 and phase 2 components, and dose-level groups. A sequential design generally evaluates participants in an ordered series of cohorts rather than assigning all participants concurrently to randomized groups. In a dose-escalation setting, such a structure can support investigation of dose and tolerability. The specific escalation rules, decision criteria, and statistical plan are not reported in the registry record, so the exact logic used to move between dose levels cannot be reconstructed.
No masking means the registry describes the study as open rather than blinded. General: Blinding can reduce the influence of knowledge about treatment assignment on assessment or reporting, while open conduct makes that knowledge available. Whether this affected endpoint assessment in this study is not reported in the registry record. The record also does not state whether response review was independent or centrally adjudicated.
How should the primary endpoint be understood? The primary endpoint is a count of participants meeting the study's response definition, with a timeframe of 2 years. The RECIST v1.0 description classifies changes in target lesions and also includes progression criteria involving non-target lesions or new lesions. A participant count is a discrete outcome. To interpret it as a response rate, the count must be considered alongside the denominator of participants assessed under the endpoint rules. Neither the response count nor the analyzed denominator is reported in the registry record.
General: For a binary outcome, an estimate of the proportion with an event is often accompanied by a confidence interval. The interval communicates uncertainty from the finite number of observations; its width depends in part on how many participants contribute and on the observed proportion. When sample sizes are limited, estimates can be imprecise, and a point estimate alone can conceal that uncertainty. No response estimate or interval is reported in the registry record.
What does sequential allocation imply for comparisons? The registry cautions that the arms are not a like-for-like control comparison and says allocation is not stated. The dose groups differ in their listed treatment doses. Therefore, comparing their outcome counts as if they were randomized treatment arms would be inappropriate. The record does not provide adjusted comparisons or a model for comparing dose cohorts. It also does not report whether any formal hypothesis tests were used.
General: In a randomized comparison, random assignment is intended to make treatment groups comparable on average with respect to measured and unmeasured baseline characteristics. In sequential cohorts, that protection is not established by randomization. Differences in observed outcomes may be related to dose, cohort composition, calendar period, or other factors, but the relevant details are not reported in the registry record. This limits causal interpretation.
How should safety counts be interpreted? The registry presents participants at risk and participants affected by serious and other adverse events for each dose level, plus deaths. These are counts, and the associated at-risk group is important context. The counts describe what was recorded within those groups. They do not establish that an event was caused by the study treatment, and they do not on their own support a formal comparison across dose levels. The registry's list of serious-event terms includes percentages, but the basis for those percentages is not reported in the registry record.
General: Adverse-event summaries can differ depending on whether they count participants, event episodes, or events meeting a particular severity threshold. A participant may experience more than one event, and the same participant may contribute to more than one event category. Without definitions and participant-level detail, aggregate counts should not be added or treated as independent observations. The record does not report event-level timing, duration, recurrence, or attribution in the information.
What is the role of sample-size planning? The study's own sample-size justification is not reported in the registry record. Planning illustrations associated with the record are described as using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with an effect defined as a stated fraction of the observed effect. Those are assumptions for an illustration, not evidence that the trial was designed or conducted as a randomized two-arm comparison. The registry also notes that time-to-event illustrations use a total event count, whereas other illustrations use participants per arm. Any such planning values should be understood as planning quantities, not as observed power or as evidence about the trial result.
General: Over-dispersion occurs when variability in count data exceeds what a simple statistical model assumes. It matters because a model that understates variability can produce confidence intervals that are too narrow and tests that are too optimistic. The primary endpoint is described as a participant count, but the registry does not report a model or evidence of over-dispersion assessment. This concept is relevant generally to count analyses, not a claim about the methods used in this study.
The registry lists no analyses in its analysis count. That does not establish which analyses investigators performed outside the registry; it indicates that analysis results and methods cannot be reconstructed from the posted record. The statistical analysis plan, missing-data rules, endpoint assessment schedule, and analysis populations are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary response-rate endpoint and multiple secondary outcomes: complete response, duration of remission, overall survival, pharmacokinetic parameters, progression-free survival using RECIST v1.1, and participants with dose-limiting toxicities. It also records 9 outcome measures, while the detailed statistical analysis count is 0. Results for the listed secondary outcomes are not reported in the registry record.
Multiplicity arises when several outcomes, time points, or comparisons are assessed. General: The more statistical questions examined, the greater the chance that some results may appear notable by chance if each is treated as a separate confirmatory test. A prespecified hierarchy or adjustment can address this issue, but the registry record does not report a multiplicity strategy, a testing hierarchy, or which outcomes were intended to be confirmatory. No adjustment method should be assumed.
Missing-data handling is also not reported in the registry record. The record does not say how participants without an endpoint assessment were classified, whether incomplete imaging assessments were excluded, or how missing follow-up was addressed. These details matter because response-rate interpretation depends on who is included in the denominator and how unevaluable participants are handled.
The analysis populations are not reported in the registry record. In particular, the record does not identify a treated population, an endpoint-evaluable population, or the number contributing to each outcome. The enrollment figure of 43 should therefore not be treated as the denominator for the primary response endpoint or every secondary outcome. Without analysis-population definitions, missing-data procedures, and outcome results, the robustness of any analysis cannot be assessed from the registry record.
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 |
|---|---|---|---|
| Dose Level 1: Bendamustine 70 mg/m2, ABT-888 50 mg | 1 | 3 | 33.3% |
| Dose Level 2: Bendamustine 90 mg/m2, ABT-888 50 mg | 3 | 3 | 100.0% |
| Dose Level 3: Bendamustine 90 mg/m2, ABT-888 100 mg BID | 3 | 6 | 50.0% |
| Dose Level 4: Bendamustine 90 mg/m2, ABT-888 150 mg BID | 2 | 4 | 50.0% |
| Dose Level 5: Bendamustine 90 mg/m2, ABT-888 200 mg BID | 2 | 5 | 40.0% |
| Dose Level 6: Bendamustine 90 mg/m2, ABT-888 300 mg BID | 5 | 15 | 33.3% |
| Dose Level 7: Bendamustine 90 mg/m2, ABT-888 400 mg BID | 3 | 7 | 42.9% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Dose Level 1: Bendamustine 70 mg/m2, ABT-888 50 mg | 0 of 3 |
| Dose Level 2: Bendamustine 90 mg/m2, ABT-888 50 mg | 1 of 3 |
| Dose Level 3: Bendamustine 90 mg/m2, ABT-888 100 mg BID | 0 of 6 |
| Dose Level 4: Bendamustine 90 mg/m2, ABT-888 150 mg BID | 0 of 4 |
| Dose Level 5: Bendamustine 90 mg/m2, ABT-888 200 mg BID | 0 of 5 |
| Dose Level 6: Bendamustine 90 mg/m2, ABT-888 300 mg BID | 0 of 15 |
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 |
|---|---|
| Dose Level 1: Bendamustine 70 mg/m2, ABT-888 50 mg | 2 of 3 |
| Dose Level 2: Bendamustine 90 mg/m2, ABT-888 50 mg | 1 of 3 |
| Dose Level 3: Bendamustine 90 mg/m2, ABT-888 100 mg BID | 1 of 6 |
| Dose Level 4: Bendamustine 90 mg/m2, ABT-888 150 mg BID | 0 of 4 |
| Dose Level 5: Bendamustine 90 mg/m2, ABT-888 200 mg BID | 0 of 5 |
| Dose Level 6: Bendamustine 90 mg/m2, ABT-888 300 mg BID | 0 of 15 |
Most frequent serious adverse event terms
| Event term | Organ system | Dose Level 1: Bendamustine 70 mg/m2, ABT-888 50 mg | Dose Level 2: Bendamustine 90 mg/m2, ABT-888 50 mg | Dose Level 3: Bendamustine 90 mg/m2, ABT-888 100 mg BID | Dose Level 4: Bendamustine 90 mg/m2, ABT-888 150 mg BID | Dose Level 5: Bendamustine 90 mg/m2, ABT-888 200 mg BID | Dose Level 6: Bendamustine 90 mg/m2, ABT-888 300 mg BID |
|---|---|---|---|---|---|---|---|
| Hematuria | Renal and urinary disorders | 1 of 3 | 1 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
| Anemia | Blood and lymphatic system disorders | 0 of 3 | 1 of 3 | 1 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
| Sepsis | Infections and infestations | 0 of 3 | 1 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 1 of 15 |
| Abdominal pain | Musculoskeletal and connective tissue disorders | 0 of 3 | 1 of 3 | 0 of 6 | 1 of 4 | 0 of 5 | 0 of 15 |
| Lung Infection | Infections and infestations | 0 of 3 | 0 of 3 | 1 of 6 | 1 of 4 | 0 of 5 | 0 of 15 |
| Hypertension | Vascular disorders | 0 of 3 | 0 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 1 of 15 |
| Alanine aminotransferase increased | Investigations | 0 of 3 | 0 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 1 of 15 |
| Aspartate aminotransferase increased | Investigations | 0 of 3 | 0 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 1 of 15 |
| Chest pain - cardiac | Cardiac disorders | 0 of 3 | 0 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 1 of 15 |
| Back pain | Musculoskeletal and connective tissue disorders | 0 of 3 | 1 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Dose Level 1: Bendamustine 70 mg/m2, ABT-888 50 mg | Dose Level 2: Bendamustine 90 mg/m2, ABT-888 50 mg | Dose Level 3: Bendamustine 90 mg/m2, ABT-888 100 mg BID | Dose Level 4: Bendamustine 90 mg/m2, ABT-888 150 mg BID | Dose Level 5: Bendamustine 90 mg/m2, ABT-888 200 mg BID | Dose Level 6: Bendamustine 90 mg/m2, ABT-888 300 mg BID |
|---|---|---|---|---|---|---|---|
| Lymphocyte count decreased | Investigations | 2 of 3 | 1 of 3 | 1 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
| Anemia | Blood and lymphatic system disorders | 1 of 3 | 1 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
| Diarrhea | Gastrointestinal disorders | 1 of 3 | 0 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
| Fatigue | General disorders | 1 of 3 | 0 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
| Hematuria | Renal and urinary disorders | 1 of 3 | 0 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
| Hypoalbuminemia | Metabolism and nutrition disorders | 0 of 3 | 1 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
| Hypocalcemia | Metabolism and nutrition disorders | 1 of 3 | 0 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
| Hypophosphatemia | Metabolism and nutrition disorders | 1 of 3 | 0 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
| Nausea | Gastrointestinal disorders | 0 of 3 | 1 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
| Platelet count decreased | Investigations | 1 of 3 | 0 of 3 | 0 of 6 | 0 of 4 | 0 of 5 | 0 of 15 |
Serious events with the highest arm-level rate: hematuria (33.3%), anemia (33.3%), back pain (33.3%), sepsis (33.3%), abdominal pain (33.3%).
The safety entries are organized by dose level and report participants at risk, participants affected by serious adverse events, participants affected by other adverse events, and deaths. For serious adverse events, the listed figures are 1 of 3 at Dose Level 1, 3 of 3 at Dose Level 2, 3 of 6 at Dose Level 3, 2 of 4 at Dose Level 4, 2 of 5 at Dose Level 5, 5 of 15 at Dose Level 6, and 3 of 7 at Dose Level 7. The recorded death counts are 0, 1, 0, 0, 0, 0, and 0, respectively.
These are descriptive group counts. They should not be read as evidence that dose level caused a difference in event frequency: the groups are not described as randomized, and the record cautions that they are not like-for-like control arms. The registry does not report whether events were judged treatment-related, or the timing and duration of events. The listed serious-event terms include Hematuria, Anemia, Back pain, Sepsis, Abdominal pain, and Duodenal hemorrhage, each shown as 33.3%; the denominator for those percentages is not reported in the registry record. Event counts do not necessarily represent distinct event episodes or distinct participants across terms.
12. What the Result Does, and Does Not, Mean
The record establishes that a completed phase 1b/2a study examined veliparib with bendamustine, with or without rituximab, in a broad set of relapsed or refractory malignancies. It documents sequential dose-level groups, a primary response-rate endpoint, and descriptive adverse-event counts. It also lists secondary outcomes that would capture response depth, durability, survival, drug exposure, and dose-limiting toxicities.
The registry does not report the primary response count or estimate, its analysis denominator, or a measure of statistical precision. It therefore does not show the magnitude of response or how precisely that magnitude was estimated. It also does not report results for the listed secondary efficacy outcomes. No conclusion about comparative efficacy can be drawn because the record does not describe a randomized control comparison and specifically cautions that the arms are not like-for-like.
The adverse-event entries show counts within dose groups, including serious events and deaths. They do not, by themselves, establish causation, comparative risk, or a dose-response relationship. The groups differ in listed dose levels, and the record does not provide the methods or detail needed to adjust or otherwise interpret differences between them.
General: A result can be statistically uncertain even when a point estimate is available, and a descriptive count is not equivalent to a causal effect estimate. A registry entry is useful for understanding the stated design, endpoints, and recorded summaries, but complete interpretation also depends on outcome data, analysis methods, participant flow, and endpoint definitions in practice. Several of those details are not reported in the registry record. The study information should therefore be read as a description of the registered investigation, not as proof that the treatment was effective or ineffective.
13. Why This Trial Matters Statistically
This study illustrates why design information is essential when interpreting clinical statistics. A response endpoint may appear straightforward, but its meaning depends on how response is defined, which participants are evaluated, and how the denominator is established. The registry gives RECIST v1.0 response categories and a 2-year timeframe, yet does not report a response count or the number assessed. Without those elements, neither the endpoint estimate nor its precision can be described.
The sequential dose-level structure also highlights the distinction between dose exploration and treatment comparison. The registry lists seven dose levels and cautions that the groups are not like-for-like controls. A reader should not interpret differences in their event counts as though they came from randomized assignment. This is especially important when cohorts are small and the statistical plan, baseline characteristics, and adjustment methods are not reported.
The record also demonstrates that safety summaries need careful denominators and clear event definitions. Participants at risk and participants affected are reported for each dose group, while serious-event terms are listed with percentages whose denominator is not stated. Such summaries can describe observed events, but they do not alone identify treatment causality or comparative safety.
Finally, the registry lists outcomes spanning response, remission duration, survival, pharmacokinetics, and toxicity. These outcomes answer different questions and may involve different analysis populations and statistical methods. Because their results and analysis details are not reported in the registry record, the registered endpoint framework can be understood, but the full evidence cannot be reconstructed. This is a useful statistical lesson: an endpoint definition, a study design, and an observed result are distinct pieces of information, and none can substitute for the others.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
Several limitations specific to this registry record constrain interpretation. The primary endpoint is described in detail, but its observed response count, denominator, estimate, and precision are not reported in the registry record. The registry also does not report the analysis population or how missing or unevaluable response assessments were handled. Enrollment of 43 cannot resolve those gaps.
The study includes a broad range of lymphoma conditions, multiple myeloma, and solid tumors. The registry does not provide disease-specific response results or explain how analyses account for this clinical heterogeneity. Without those details, the overall primary endpoint cannot be linked to a particular malignancy group.
The design is sequential and unmasked. The allocation method is not stated, and the registry cautions that the listed groups are not like-for-like controls. Dose-level differences in adverse-event counts therefore cannot be interpreted as randomized comparisons. The registry does not report baseline group characteristics, escalation rules, dose-limiting toxicity criteria, or a statistical analysis plan.
The treatment description is incomplete: it specifies veliparib and bendamustine schedules but truncates the account of the post-dose-determination cohort. Although rituximab is included in the title and intervention list, its schedule is not reported in the registry record. The registry's serious-event percentages also lack a stated denominator in the information recorded. Attribution, event timing, and event-level detail are not reported.
Finally, results for secondary outcomes are not reported in the registry record, despite the listed outcomes and outcome-measure count. These gaps prevent assessment of durability, survival, pharmacokinetics, and the broader safety profile from the registry information alone.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Veliparib, Bendamustine Hydrochloride, and Rituximab in Treating Patients With Relapsed or Refractory Lymphoma, Multiple Myeloma, or Solid Tumors — NCT01326702.
- Registry record last updated 2019-12-16; status last verified 2019-11.
- Results first posted 2019-12-16.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
The registry record describes a completed, unmasked, sequential phase 1b/2a study sponsored by the National Cancer Institute (NCI), with enrollment of 43. The study evaluated veliparib with bendamustine, with or without rituximab, in patients with relapsed or refractory lymphoma, multiple myeloma, or solid tumors. It lists seven dose-level groups and identifies response rate, assessed using RECIST v1.0, as the primary endpoint with a 2-year timeframe.
The registry reports group-level adverse-event counts and lists several secondary outcomes. It does not report the primary response result, the analyzed population, missing-data methods, a statistical analysis plan, or results for the listed secondary outcomes. The dose groups are not described as randomized control arms, and the registry cautions against treating them as like-for-like comparisons.