Lutonix or Inpact for tHE tReatment Of fEmeropopliteal Stenosis - Drug Coated Balloon: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Lutonix or Inpact for tHE tReatment Of fEmeropopliteal Stenosis - Drug Coated Balloon (NCT02812966), a randomized na study. The primary outcome is Primary Patency (Peak Systolic Velocity Ratio<=2.4).

2. Clinical Question

The trial asked whether primary patency at 12 months differed between two drug-coated balloon devices for treating femoropopliteal stenosis in people with peripheral arterial disease who had clinical indications for angioplasty. The registry describes the comparison as a hypothesis; it does not report an estimate of the difference or data with which to assess it.

The comparison concerns a defined ultrasound criterion together with whether either specified repeat-treatment event occurred. It is not a reported comparison of all possible measures of vessel status, symptoms, or quality of life. The registry lists target lesion revascularization rate as a secondary outcome, but does not report its results. Because no participants were analyzed for the primary outcome, the clinical question remains unanswered by the posted outcome data. The record does not report whether the devices differed in patency, nor does it support a conclusion that they were equivalent.

3. Trial Design

This was a randomized, parallel-group study with no masking. The registry lists Lutonix and IN.PACT as the two device interventions and records enrollment of 35. It gives the study status as terminated. The recorded start was 2016-04, and primary completion was 2019-12-02. The phase is listed as NA.

The trial concerned peripheral arterial disease and compared the devices in participants presenting with significant disease and clinical indications for angioplasty. The registry does not report additional eligibility criteria, details of the randomization sequence, allocation concealment, or how participants were assigned to each device. Randomization is the stated allocation method, but the registry record does not provide enough information to assess its implementation.

No masking was used. This means the design was open-label as recorded; the record does not state whether outcome assessment was separately masked. The primary endpoint was intended for assessment at 12 months. Its definition combined a peak systolic velocity ratio at or below 2.4 by duplex ultrasound with the absence of target lesion revascularization or target lesion bypass.

The registry states that data were not collected for the primary outcome and that an insufficient number of participants had enrolled to perform data analysis before study closure. It also reports zero participants analyzed for that outcome. Consequently, the enrolled total should not be mistaken for the number contributing to an efficacy comparison. The number assigned to each group for the primary analysis, participant flow, and reasons for nonparticipation in outcome assessment are not reported in the registry record.

The record lists target lesion revascularization rate as a secondary outcome and indicates two outcome measures, but gives no secondary-outcome results. It reports no analyses. Details of the planned statistical analysis, the intended analysis population, and the rationale for the enrollment target 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.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Data were not collected. Insufficient number of participants enrolled to perform data analysis prior to study closure. No data displayed because outcome measure had zero total participants analyzed.

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 Primary Patency (Peak Systolic Velocity Ratio<=2.4), measured over 12 months.

The primary endpoint was primary patency at 12 months. The registry defined it as a peak systolic velocity ratio at or below 2.4, measured by duplex ultrasound, with no target lesion revascularization or target lesion bypass. Thus, the criterion combined an ultrasound measurement with the absence of specified subsequent procedures. The registry does not report a primary-outcome value for either device group.

General explanation: Duplex ultrasound estimates blood-flow velocity. A velocity ratio compares measurements across a vessel segment and can be used as a non-invasive indicator of narrowing. A prespecified threshold turns that continuous measurement into a classification for an endpoint. The trial's definition also included the absence of revascularization or bypass, so a qualifying ultrasound measurement alone would not be sufficient for the stated primary-patency criterion.

Endpoints of this kind can provide a reproducible way to compare vessel status at a planned follow-up time, while incorporating whether a repeat procedure occurred. Interpretation depends on consistent measurement, complete follow-up, and clear handling of events and missing assessments. The registry does not report measurement procedures beyond duplex ultrasound, nor does it describe how missing measurements or events were handled in analysis.

In this record, the primary endpoint is described but not observed in an analyzed participant set: the registry says data were not collected and no participants were analyzed. There is therefore no reported patency proportion, between-group estimate, or uncertainty interval to interpret. The endpoint definition explains what the investigators intended to measure, not what the trial found.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies a randomized, parallel-group comparison without masking. These features describe the planned design, but the statistical analysis methods are not reported in the registry record. No analysis is listed, and the primary outcome has zero participants analyzed. Statistical concepts can clarify what such a comparison would ordinarily seek to estimate, but they cannot substitute for the missing trial results.

What a randomized comparison estimates

General explanation: In a randomized study, the intended comparison is between outcomes in groups assigned to different interventions. Random assignment aims to make treatment groups comparable on average with respect to characteristics that could affect the outcome. It does not guarantee identical groups, and its usefulness depends on appropriate implementation and outcome collection. The registry records randomization, but details of the sequence, concealment, and participant flow are not reported in the registry record.

For this trial, the intended outcome was the proportion meeting the primary-patency definition at 12 months in each device group, followed by a comparison between groups. That definition required a peak systolic velocity ratio at or below 2.4 and no target lesion revascularization or target lesion bypass. The registry supplies no analyzed group outcomes, so neither group proportion nor a between-group contrast is reported.

Precision and uncertainty

General explanation: A confidence interval describes a range of values compatible with an estimated effect under a statistical model and its assumptions. Its width communicates precision: a wider interval indicates greater uncertainty, while a narrower interval indicates greater precision. An interval is not a guarantee that the true effect lies within its limits. Because the registry reports no primary-outcome analysis, it provides no estimate or confidence interval for this comparison.

A p-value, when reported, addresses how compatible data are with a specified null hypothesis under stated assumptions. It does not measure the size or clinical importance of an effect. No primary-outcome p-value is reported. The registry also gives no analysis details from which to determine whether a particular test, model, or adjustment was planned.

Outcome definition and analysis choices

General explanation: A binary endpoint classifies each participant as meeting or not meeting a criterion. For a composite definition, each component and the rule combining them matter. In this trial, the endpoint joined the ultrasound threshold with absence of two specified procedures. Analysis could depend on how assessments not obtained at the intended follow-up were classified, and on whether participants were analyzed according to assigned groups or another rule. Those handling decisions are not reported in the registry record.

The primary endpoint has a stated 12-month timeframe, but follow-up procedures, the permissible timing window, and outcome adjudication are not described in the record. It is also not stated whether an event before the scheduled ultrasound assessment would count as failure, although the endpoint definition includes no revascularization or bypass. No assumptions about those details can be inferred from the endpoint label alone.

Planning calculations and observed results

The registry describes a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation. It states that the effect to detect is a stated fraction of the observed effect. Such calculations are planning illustrations, not observed power and not trial findings. Sample sizes in a planning calculation do not show how many participants actually completed follow-up or contributed to an outcome analysis.

The record does not give an analyzed primary effect from which to judge the comparison, and the primary outcome explicitly has no analyzed participants. Any planning illustration should therefore be read only as a hypothetical design aid under its stated assumptions, not as a substitute for outcome data or evidence about device performance. The registry does not report the trial's own sample-size justification.

Why model assumptions matter

General explanation: Statistical models make assumptions about how outcomes vary and how observations relate to one another. Over-dispersion occurs when count variability exceeds what a chosen model expects; if ignored, standard errors can be too small and uncertainty can be understated. The registry does not report an analysis model for this trial, and the absent primary analysis gives no basis to assess over-dispersion or other model diagnostics. This concept is general and should not be mistaken for a feature established in this study.

Likewise, adjustment for baseline factors, handling of multiple outcomes, and sensitivity analyses can affect interpretation. None of these methods is described in the registry record. No adjusted estimate, per-protocol result, or sensitivity analysis is reported. With no primary outcome analysis, there is no result to reanalyze from the registry information.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary outcome and target lesion revascularization rate as a secondary outcome. It does not report a statistical plan explaining how multiple outcomes or multiple comparisons would be handled. In general, testing several hypotheses can increase the chance of a false-positive finding if each test is interpreted without accounting for the others. That is a general statistical concern; no multiplicity procedure or multiplicity-adjusted result is reported for this trial.

The primary outcome was not analyzed: the registry states that data were not collected, that an insufficient number of participants enrolled for analysis before study closure, and that zero participants were analyzed. The secondary outcome has no reported result. The record does not say whether outcome data were unavailable for all enrolled participants for the same reason or whether different collection issues applied to different measures.

Missing outcome information should not automatically be treated as a negative outcome, a treatment failure, or a favorable result. Statistical handling of missing assessments depends on why they are missing and on assumptions about their relationship to outcomes and treatment. The registry does not report a missing-data method, sensitivity analysis, imputation, or participant-level follow-up information. It also does not report whether any interim analyses were conducted.

The analysis population is not described in the registry record. It does not state whether an intention-to-treat, per-protocol, or other population was planned, nor does it provide group-specific numbers contributing to an analysis. With no analyzed primary endpoint, neither missing-data assumptions nor population definitions can be evaluated against an efficacy result.

11. Safety Results

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

Deaths

Other (non-serious) adverse events

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

Most frequent serious adverse event terms

Serious events with the highest arm-level rate: subdural hematoma (5.6%).

The registry lists serious-event information separately for the two device groups. For Lutonix, it records 1 serious event affecting 1 participant among 18 at risk, 0 other adverse events affecting participants among 18 at risk, and 1 death. For IN.PACT, it records 0 serious events among 17 at risk, 0 other adverse events among 17 at risk, and 0 deaths. These are descriptive registry counts; they are not a comparative safety analysis.

The record identifies subdural hematoma as a serious adverse event term and gives 5.6%. It does not state in the listed term entry which group the percentage refers to, so the percentage should not be assigned to a group based on these details alone. The record also does not establish whether an event was caused by a device or procedure. A count recorded during a trial is not, by itself, evidence of causation.

The denominators in the safety entries are participants at risk, and they differ between groups. No adjusted comparison, uncertainty interval, or formal test of safety differences is reported. The small enrolled groups and the absence of an analysis make these figures unsuitable for drawing a precise comparative conclusion. They should be read as the safety events recorded in the registry, with the limitations of the available information.

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

The record does establish that investigators planned a randomized comparison of Lutonix and IN.PACT drug-coated balloons for femoropopliteal stenosis in people with peripheral arterial disease. It also defines a primary patency outcome at 12 months and records that the trial was terminated. These registry entries describe the research question and study status; they do not provide an estimate of comparative patency.

The most important boundary on interpretation is the absence of analyzed primary-outcome data. The registry says data were not collected and reports zero participants analyzed for the endpoint. Therefore, the posted results do not show whether the patency criterion was met more often in either group, whether the groups were similar, or how uncertain a comparison would be. No result means no basis for a conclusion of superiority, equivalence, or lack of difference.

The recorded enrollment of 35 is not a substitute for the missing outcome analysis. Enrollment does not establish how many participants completed the 12-month assessment, whether the endpoint was measured, or how participants were distributed across an analysis population. Those details are not reported in the registry record.

The safety counts provide a limited descriptive account: a serious event and a death are listed for the Lutonix group, while none are listed for the IN.PACT group; non-serious events are listed as zero for both groups. Those counts do not establish that the device caused an event or that one group is safer. The record does not provide a comparative safety analysis, and the group sizes and event counts do not resolve that question.

The appropriate reading is therefore narrow. The trial record documents an intended device comparison and some registry safety entries, but its primary efficacy question remains unanswered in the posted outcome data. The absent result should not be interpreted as evidence for either device, as evidence of no effect, or as proof that the devices perform alike.

13. Why This Trial Matters Statistically

This trial matters statistically because its design and endpoint are recorded, but the outcome needed to answer the main comparison is not. The contrast between a clearly stated question and zero analyzed primary-outcome participants illustrates why a registered hypothesis is not the same as an estimated treatment effect. Without outcome data, no direction, magnitude, or precision can be established.

The case also highlights the difference between enrollment and analysis. The registry records enrollment of 35, while stating that too few participants had enrolled to perform data analysis before study closure. The enrolled total alone cannot tell readers how many had a 12-month assessment or contributed to the planned endpoint. Participant flow and analysis counts are essential context for interpreting a trial, particularly when a study ends before analysis.

The endpoint combines a measured ultrasound threshold and the absence of specified procedures. Such a definition can be clinically structured, but it depends on complete and consistent assessment of each component. When the registry reports that outcome data were not collected, readers cannot evaluate endpoint completeness, measurement precision, or the contribution of repeat procedures to the result.

Finally, the record shows why descriptive adverse-event counts should be kept separate from comparative inference. Counts can report what was entered for each group, but they do not establish causation or quantify uncertainty. In this trial, the safety entries do not repair the missing primary comparison. Statistically, the key conclusion is not a device effect; it is the limitation imposed by absent outcome analysis.

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 main trial-specific limitation is that the registry reports no collected or analyzed primary-outcome data. It attributes the lack of analysis to an insufficient number of participants enrolled before study closure. With zero participants analyzed for primary patency, there is no estimate of the intended 12-month comparison and no way to assess its precision.

The study is recorded as terminated, but the registry does not report a detailed account of the circumstances leading to termination or the enrollment target's justification. It records 35 enrolled participants, but does not provide group-specific primary-analysis counts, a participant flow account, or the number with completed follow-up. The number assigned to each group is therefore not established by the primary-outcome information.

Although randomization and no masking are recorded, implementation details are not reported in the registry record. The record does not describe allocation concealment, masked endpoint assessment, baseline characteristics for analyzed groups, or the analysis population. These omissions limit assessment of the planned comparison, though the absence of outcome data is the more fundamental constraint.

The primary outcome is defined, but the registry does not describe missing-assessment handling, the analysis model, adjustment variables, sensitivity analyses, or multiplicity procedures. It lists a secondary outcome without reporting its result. The safety information is limited to registry counts and a serious-event term; it does not include a comparative safety analysis or establish causation.

These limitations mean the record can describe the intended study and its reported status but cannot support an efficacy conclusion. The missing analysis should not be interpreted as a null result or as evidence that the devices had equivalent outcomes.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Lutonix or Inpact for tHE tReatment Of fEmeropopliteal Stenosis - Drug Coated Balloon — NCT02812966.
• Registry record last updated 2024-10-08; status last verified 2024-07.
• Results first posted 2024-07-30.
• 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.

18. Record Summary

NCT02812966 was a randomized, parallel-group, unmasked trial comparing Lutonix and IN.PACT drug-coated balloons for peripheral arterial disease. The registry records enrollment of 35, study status as terminated, a start of 2016-04, and primary completion on 2019-12-02.

The primary outcome was 12-month primary patency, defined by a peak systolic velocity ratio at or below 2.4 on duplex ultrasound and no target lesion revascularization or target lesion bypass. The registry states that data were not collected and that zero participants were analyzed for this outcome. Target lesion revascularization rate is listed as a secondary outcome, with no result reported.

Safety entries list 1 serious event and 1 death in the Lutonix group, and 0 serious events and 0 deaths in the IN.PACT group; other adverse events are listed as 0 in both groups. These counts are descriptive and do not establish causation or a comparative safety effect. The posted record does not answer the primary patency question.