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 Use of ABI-007 for the Prevention of Vascular Access Graft Failure in Patients Undergoing Hemodialysis (NCT00249002), a na phase 2 study. The primary outcome is Percentage of Participants With Discontinued, Delayed or Interrupted Therapy.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00249002 |
| Phase | Phase 2 |
| Condition | Hemodialysis Graft Dysfunction |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 9 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Celgene |
| Results posted | Yes |
2. Clinical Question
The trial concerned people undergoing hemodialysis who had vascular access graft dysfunction. It evaluated ABI-007 after angioplasty, with the primary question focused on whether toxicities or adverse events led to treatment being discontinued, delayed, or interrupted through week 21.
Population
Hemodialysis patients with vascular access graft dysfunction. The registry lists a treated population for the primary outcome and an enrollment of 9.
Intervention
ABI-007, 35 mg/m^2 given intravenously into the arteriovenous graft within 96 hours after angioplasty, followed by repeat treatment during weeks 5, 13 and 21.
Comparator
No comparator group is listed. The trial is described as single-group, and allocation is recorded as NA; it is not a randomized comparison.
Primary question
What percentage of treated participants had therapy discontinued, a dose delayed, or a dose interrupted because of toxicities or adverse events, up to week 21? The result for this endpoint is not reported in the registry record.
This is a safety and treatment-delivery question, not a direct comparison of ABI-007 with another treatment. The registry also names outcomes concerning cardiovascular complications, time to graft failure or intervention, and lesion patency. Their names indicate the topics considered, but do not establish what the results were. The registry record does not report an analyzed treatment effect against a control group.
3. Trial Design
The registry describes a Phase II pilot trial of ABI-007 for prevention of vascular access graft failure in patients undergoing hemodialysis. It lists a single-group model, no masking, allocation as NA, and enrollment of 9. These features mean the record does not describe a blinded, randomized comparison with a separate control arm. The reason for using this design, and any protocol rationale for the enrollment target, are not reported in the registry record.
The study start date is 2005-11-01 and the primary completion date is 2007-11-01. Its status is terminated. The reason for termination and whether it was related to safety, recruitment, operational circumstances, or another cause are not reported in the registry record; no explanation should be inferred from the status alone.
The listed intervention was ABI-007 35 mg/m^2, administered intravenously into the arteriovenous graft within 96 hours after angioplasty, with repeat treatments during weeks 5, 13 and 21. The brief summary says the study was designed to confirm safety of the proposed dose and schedule and to obtain preliminary effectiveness data. That statement describes the study’s aims, not evidence that either aim was achieved.
The primary outcome concerns discontinuation, delay, or interruption of therapy due to toxicities or adverse events up to week 21, among the treated population. Listed secondary outcomes include participants with arthrosclerotic cardiovascular complications, Kaplan–Meier estimates for time to graft failure or intervention, and the percentage with patency of index and non-index lesions at 24 weeks. The registry lists 13 outcome measures, but does not report a statistical analysis for the primary endpoint.
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
| Stage | ABI-007 |
|---|---|
| STARTED | 9 |
| COMPLETED | 2 |
| NOT COMPLETED | 7 |
Reasons for not completing this period:
| Reason | ABI-007 |
|---|---|
| Adverse Event | 2 |
| Study cancellation | 3 |
| Other | 2 |
Analysis population for the primary outcome, as defined in the registry: Treated population
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 | ABI-007 |
|---|---|---|
| Participants analysed | 9 | |
| Age, Continuous | years | 67.6 (SD 8.16) |
| Age, Customized: <65 years | participants | 4 |
| Age, Customized: >=65 years | participants | 5 |
| Sex: Female, Male: Female | Participants | 6 |
| Sex: Female, Male: Male | Participants | 3 |
| Race/Ethnicity, Customized: American Indian or Alaska Native | participants | 0 |
| Race/Ethnicity, Customized: Asian | participants | 0 |
| Race/Ethnicity, Customized: Native Hawaiian or Other Pacific Islander | participants | 0 |
| Race/Ethnicity, Customized: Black of African heritage | participants | 7 |
| Race/Ethnicity, Customized: White, Non-Hispanic and Non-Latino | participants | 2 |
| Race/Ethnicity, Customized: White, Hispanic or Latino | participants | 0 |
| Race/Ethnicity, Customized: Other | participants | 0 |
| Weight | kg | 71.78 (SD 13.271) |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Participants With Discontinued, Delayed or Interrupted Therapy, measured over up to week 21.
| 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 treated participants who had ABI-007 therapy discontinued, a dose delayed, or a dose interrupted because of toxicities or adverse events, up to week 21. It combines several ways that safety concerns could alter the planned treatment course. The endpoint is therefore about treatment delivery in the context of adverse effects, rather than graft patency or a direct measure of treatment benefit.
As a general statistical concept, a treatment-modification endpoint can help describe whether participants were able to follow a planned regimen as intended. It is important to define the events included and the observation period, because a delay, an omitted dose, and discontinuation do not necessarily represent the same degree or duration of treatment exposure. Here, the registry description identifies the included situations and attributes them to toxicities or adverse events.
The registry specifies a treated population and a timeframe up to week 21. It does not report the number of participants meeting the endpoint, the percentage, or an uncertainty interval. The stated result therefore cannot be interpreted as an observed frequency from the record. The protocol’s detailed rules for classifying events or handling participants with incomplete observation are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the primary safety endpoint but does not report its result. It gives no percentage for participants whose therapy was discontinued, delayed, or interrupted because of toxicities or adverse events, and no confidence interval or primary-endpoint analysis is listed. As a result, the record does not establish the observed frequency of this outcome or how precisely it was estimated.
The trial is described as single-group, with no comparator listed. Any outcome observed in such a group would describe participants receiving the regimen under study; without a concurrent control group, the record cannot establish how the same outcomes would have differed under another treatment or no treatment. This limitation applies to interpretation of effectiveness as well as safety. The brief summary states that preliminary effectiveness data were sought, but the listed secondary outcome names alone do not supply those results.
The registry lists an enrollment of 9. That is the recorded enrollment, not a reported primary-endpoint denominator or proof that every enrolled participant was treated and observed through the endpoint timeframe. Although the primary outcome specifies the treated population, the number treated and the number with complete endpoint data are not reported in the registry record. No confidence interval is available to show the statistical precision of the primary result.
The safety summary reports 6 affected among 9 at risk in the serious adverse-event category and 7 affected among 9 at risk in the other adverse-event category. It also lists serious-event terms with percentages. These summaries describe adverse-event reporting in the trial; they do not by themselves show whether an event was caused by ABI-007. The number of deaths is not reported in the registry record.
The registry lists secondary outcomes concerning cardiovascular complications, time to graft failure or intervention, and patency at 24 weeks. It does not provide their results in the record described by these registry entries. The listed number of outcome measures is 13, while the number of analyses is 0. This means there is no reported analysis to interpret for the primary outcome; it does not establish that no data were collected or that no analyses occurred outside the registry record.
9. Statistical Methods Explained
The registry identifies the primary outcome as a percentage of participants. In general, a percentage for a binary outcome describes the share of a defined group that meets a specified event definition. For this trial, the event definition includes therapy discontinuation, a delayed dose, or an interrupted dose attributed to toxicities or adverse events. The denominator should correspond to the population specified for analysis. The record names the treated population, but does not report how many treated participants contributed data or the observed percentage.
What does a confidence interval add?
As a general statistical explanation, a confidence interval expresses uncertainty around an estimate. It is not a guarantee that the true value falls within the particular interval, and it does not resolve possible bias in how participants were selected, followed, or assessed. For a percentage, the interval’s width depends in part on the amount of information available and on the observed event frequency. No interval for the primary endpoint is reported in the registry record, so its precision cannot be assessed from that endpoint.
What does the single-group design allow?
A single-group study can describe outcomes observed among participants receiving the regimen. It does not provide a randomized concurrent group for estimating a comparative treatment effect. A change in an outcome over time, or an event observed after treatment, cannot by itself distinguish treatment effects from the course of the underlying condition, effects of other care, or chance. These are general design considerations; the record does not report a comparative analysis.
The registry records allocation as NA and masking as none. It does not describe random assignment or masking. The reason for these design choices is not reported in the registry record. In general, lack of masking can affect how outcomes are assessed or reported, especially when judgment is involved; the extent of any such effect in this trial is not reported.
How should time-to-event outcomes be understood?
One listed secondary outcome is Kaplan–Meier estimates for time to graft failure or intervention. In general, Kaplan–Meier methods estimate the probability of remaining free of an event over time while accounting for participants whose event status becomes unknown before the observation period ends. Such methods rely on assumptions about censoring, including that censoring is not related to the future event risk in a way that distorts the estimate. The registry names the method and outcome, but does not report estimates, event counts, censoring details, or an analysis plan for that outcome.
The primary endpoint is not the listed time-to-event outcome. Its description concerns whether treatment was discontinued, delayed, or interrupted up to week 21. A binary percentage and a time-to-event estimate answer different questions: one concerns whether a defined event occurred during a stated period, while the other concerns when an event occurred and how event-free probability changes over time. The registry does not report the detailed statistical procedure used for either outcome.
What do the planning assumptions mean?
The record describes a planning illustration based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect, and distinguishes illustrations for time-to-event outcomes from those for other outcomes. These are planning assumptions, not evidence of the trial’s actual design: the trial itself is listed as single-group, with no randomized comparison. Specific planning values and fractions are not reported in the registry record.
In general, a sample-size calculation estimates how much information a future study may need under stated assumptions. It is not observed power, does not show that a study detected an effect, and does not establish that the assumptions are realistic. A planning illustration based on an observed effect can also depend on the stability of that initial estimate. No sample-size justification for this pilot, and no trial-specific statistical analysis plan, are reported in the registry record.
The registry lists 13 outcome measures and 0 analyses. The record does not specify the statistical test for the primary endpoint, covariate adjustment, confidence-interval method, interim analyses, or handling of missing endpoint observations. Those methods should not be inferred from the outcome label or from general statistical practice.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 13 outcome measures, including the primary treatment-modification endpoint and secondary outcomes concerning cardiovascular complications, graft failure or intervention, and lesion patency. When a study examines multiple outcomes, the chance of at least one apparently unusual result can increase if each is assessed separately. General approaches to this issue include prespecifying a primary outcome and adjusting or otherwise organizing inference across multiple comparisons. The registry record does not report a multiplicity strategy, a hierarchy among secondary outcomes, or a statistical analysis plan.
The record lists 0 analyses. It therefore does not provide reported inferential results for the primary endpoint or the named secondary outcomes. It also does not say whether any interim analyses were planned or performed. Their status is not reported in the registry record.
The primary outcome specifies a treated population, but the number treated and the amount of missing endpoint information are not reported in the registry record. The record does not describe whether participants who missed visits, stopped treatment, or lacked a final assessment were included, excluded, or handled in another way. It also does not report methods for imputing missing observations or sensitivity analyses. These details matter because incomplete follow-up can affect both the event percentage and its interpretation. No assumptions about missing data can be made from the endpoint definition alone.
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 |
|---|---|---|---|
| ABI-007 | 6 | 9 | 66.7% |
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 |
|---|---|
| ABI-007 | 7 of 9 |
Most frequent serious adverse event terms
| Event term | Organ system | ABI-007 |
|---|---|---|
| Anastomotic stenosis | Injury, poisoning and procedural complications | 2 of 9 |
| Contrast media reaction | Injury, poisoning and procedural complications | 1 of 9 |
| Graft thrombosis | Injury, poisoning and procedural complications | 1 of 9 |
| Gastrointestinal haemorrhage | Gastrointestinal disorders | 1 of 9 |
| Cerebrovascular accident | Nervous system disorders | 1 of 9 |
Most frequent non-serious adverse event terms
| Event term | Organ system | ABI-007 |
|---|---|---|
| Anastomotic stenosis | Injury, poisoning and procedural complications | 3 of 9 |
| Vascular graft complication | Injury, poisoning and procedural complications | 2 of 9 |
| Neuropathy peripheral | Nervous system disorders | 2 of 9 |
| Diarrhoea | Gastrointestinal disorders | 2 of 9 |
| Cough | Respiratory, thoracic and mediastinal disorders | 2 of 9 |
| Contrast media reaction | Injury, poisoning and procedural complications | 1 of 9 |
| Procedural pain | Injury, poisoning and procedural complications | 1 of 9 |
| Bradycardia | Cardiac disorders | 1 of 9 |
| Cardiovascular disorder | Cardiac disorders | 1 of 9 |
| Hypertrophic obstructive cardiomyopathy | Cardiac disorders | 1 of 9 |
Serious events with the highest arm-level rate: anastomotic stenosis (22.2%), contrast media reaction (11.1%), graft thrombosis (11.1%), gastrointestinal haemorrhage (11.1%), cerebrovascular accident (11.1%).
The registry’s safety summary lists 6 affected among 9 at risk for serious adverse events and 7 affected among 9 at risk for other adverse events. These are separate categories in the record. The figures should be read as safety summaries, not as a comparison between ABI-007 and a control treatment, because no control group is listed.
The serious-event terms and percentages listed are anastomotic stenosis, 22.2%; contrast media reaction, 11.1%; graft thrombosis, 11.1%; gastrointestinal haemorrhage, 11.1%; and cerebrovascular accident, 11.1%. These terms describe events reported in the safety summary. The record does not establish from these figures whether each event was caused by ABI-007. The percentages should not be treated as a count of distinct participants, because the record does not state whether a participant could contribute more than one event term.
The deaths field is not reported in the registry record. The record also does not provide event timing, severity grading beyond the serious/other categories, exposure-adjusted rates, or a comparison with background event rates. These omissions limit interpretation; they do not imply that no deaths or other events occurred.
12. What the Result Does, and Does Not, Mean
The registry record establishes the trial’s stated purpose, design, treatment schedule, and endpoint definitions. It describes a Phase II pilot intended to assess safety of the proposed ABI-007 dose and schedule and to obtain preliminary effectiveness data. The trial was single-group, had no masking, and was terminated. Its primary safety endpoint was the percentage of treated participants with therapy discontinued, delayed, or interrupted because of toxicities or adverse events through week 21.
The record does not report the primary endpoint result, a confidence interval, or a statistical analysis. It therefore does not show how often treatment modification occurred or how precise an estimate would be. The listed adverse-event summaries provide descriptive safety information, but they are not a controlled comparison and do not establish that ABI-007 caused the reported events.
The outcome names related to graft failure, intervention, cardiovascular complications, and patency indicate topics included in the registry. Their results are not reported in the registry record. Naming an outcome does not show that a benefit or harm was observed, and the study’s stated aim to obtain preliminary effectiveness data is not itself evidence of effectiveness.
More generally, findings from a single-group pilot cannot establish how outcomes compare with an alternative. The registry enrollment of 9 also does not, on its own, establish the number treated, the number with complete follow-up, or the precision of any particular estimate. These matters require endpoint results and analysis details that are not reported in the registry record.
13. Why This Trial Matters Statistically
This trial is statistically informative as an example of the difference between a study’s aims and the results available for interpretation. The registry describes a safety-oriented primary endpoint and an intention to collect preliminary effectiveness data, but does not report an analysis for the primary endpoint. Without the observed endpoint value and its uncertainty, the record cannot quantify the frequency of treatment interruption or delay.
The single-group structure also matters. A study can report what occurred among treated participants, but a comparator is needed to make a direct estimate of how outcomes differ under another treatment strategy. The registry’s listed secondary outcomes may be relevant to graft function and safety, yet their names do not substitute for analyzed results. The absence of a control group should remain visible when interpreting any descriptive findings.
The record also illustrates why endpoint definitions and analysis populations matter. The primary measure combines discontinuation, delayed dosing, and interrupted dosing, and specifies the treated population. The number treated and the handling of incomplete observations are not reported in the registry record. Without those details, it is difficult to assess the denominator, missing-data consequences, or reproducibility of a percentage estimate.
Finally, a planning illustration should be distinguished from evidence generated by the trial. The registry describes assumptions for such an illustration, but the trial is not listed as a randomized two-arm study. Planning calculations do not create a comparator, establish observed power, or replace a reported statistical analysis. Clear separation of study design, planning assumptions, outcome definitions, and actual results is essential to sound interpretation.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The registry record provides limited information for evaluating the primary endpoint. Although the endpoint definition, timeframe, and treated population are stated, the result, denominator, uncertainty interval, and statistical test are not reported. The record also lists 0 analyses, so there is no reported primary-outcome analysis to assess.
The single-group design has no listed control arm, and allocation is recorded as NA. The trial is therefore not a like-for-like randomized comparison. The record does not report why the study was terminated, and termination alone does not establish a safety or efficacy explanation. The reason for the enrollment target and any sample-size justification are also not reported in the registry record.
Information needed to interpret completeness and possible bias is absent: the number treated, participant flow, endpoint-specific missingness, follow-up completeness, and handling of missing observations are not reported. The record also does not describe adjudication or classification procedures for the primary endpoint, or whether event assessments were independent of treatment knowledge.
For the safety summary, the record does not report deaths, event timing, detailed severity, or whether the listed serious-event percentages represent participants or events. It does not provide a control rate for context. The named secondary outcomes have no reported results in this record, and multiplicity procedures are not reported. These limits prevent conclusions about comparative effectiveness, causal attribution, or the precision of the main endpoint.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Use of ABI-007 for the Prevention of Vascular Access Graft Failure in Patients Undergoing Hemodialysis — NCT00249002.
- Registry record last updated 2019-11-25; status last verified 2019-11.
- Results first posted 2012-03-13.
- 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
NCT00249002 is listed as a terminated Phase II pilot of ABI-007 in hemodialysis patients with vascular access graft dysfunction. The registry describes a single-group study with no masking, allocation recorded as NA, and enrollment of 9. The treatment schedule was ABI-007 35 mg/m^2 intravenously into the arteriovenous graft within 96 hours after angioplasty, with repeat treatment during weeks 5, 13 and 21.
The primary outcome was the percentage of treated participants whose therapy was discontinued, delayed, or interrupted because of toxicities or adverse events up to week 21. Its result and statistical analysis are not reported in the registry record. The record lists 13 outcome measures and 0 analyses, along with serious and other adverse-event summaries. It does not report the reason for termination, deaths, or results for the named secondary outcomes.