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 CVT-ISR First in Human Trial for Coronary In-Stent Restenosis (NCT05731700), a na na study. The primary outcome is The Primary Safety Endpoint for the CVT-ISR Study: Freedom From Target Lesion Failure (TLF) Rate.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT05731700 |
| Phase | NA |
| Condition | In-stent Restenosis |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 51 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Abbott Medical Devices |
| Results posted | Yes |
2. Clinical Question
Population
Participants with in-stent restenosis in previously treated native coronary artery lesions. The registry describes treatment of a single in-stent restenosis lesion per participant. Enrollment was 51.
Intervention
A drug-eluting balloon, identified as an everolimus-coated percutaneous transluminal coronary angioplasty catheter. The study is described as a first-in-human clinical investigation.
Comparator
No comparator group is listed. The model is single-group, and allocation is recorded as NA. The intervention group therefore should not be read as one arm of a randomized comparison.
Primary question
At 6 months post-index procedure, what was the freedom-from-target-lesion-failure rate? Target lesion failure is defined as a composite of cardiovascular death, target vessel myocardial infarction, and clinically driven target lesion revascularization. A numerical result for this endpoint is not reported in the registry record.
The stated aim is to assess safety and inhibition of restenosis with the CVT Everolimus-coated PTCA Catheter in people presenting with in-stent restenotic lesions. The primary endpoint focuses on clinically important events associated with the treated lesion and its related vessel. Because the study has no listed comparator group, its clinical question is descriptive: it concerns outcomes observed among participants treated in this study, rather than a direct estimate of a difference between treatments.
3. Trial Design
NCT05731700, titled “CVT-ISR First in Human Trial for Coronary In-Stent Restenosis,” is recorded as a completed, single-group study sponsored by Abbott Medical Devices. The registry lists enrollment of 51 participants, with study start on 2021-10-20 and primary completion on 2022-09-19. The phase is NA. Allocation is NA and masking is NONE.
The intervention is identified as a Drug Eluting Balloon, a device. Its arm description specifies treatment of a single in-stent restenosis coronary artery lesion with a drug-eluting balloon. The official title describes an everolimus-coated percutaneous transluminal coronary angioplasty catheter and a clinical evaluation in subjects with in-stent restenosis of previously treated coronary artery lesions. The brief summary identifies safety and inhibition of restenosis as the study’s goals.
The registry lists a primary safety endpoint assessed at 6 months post-index procedure. It also lists secondary outcomes covering target lesion and target vessel failure, clinically driven revascularization, vascular access site complications, and measures of lesion, technical, and clinical success. The record gives no numerical results for these outcomes. It lists 11 outcome measures and no analyses.
General explanation: a single-group study can describe events and outcomes among treated participants, but without a comparator it cannot directly distinguish outcomes associated with the intervention from outcomes that might also occur under another treatment or without the intervention. The registry record does not describe a randomized treatment allocation or a control group. Its posted design information therefore supports a description of the study cohort and its recorded outcomes, not a like-for-like treatment comparison.
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 | Drug Eluting Balloon |
|---|---|
| STARTED | 51 |
| COMPLETED | 48 |
| NOT COMPLETED | 3 |
Reasons for not completing this period:
| Reason | Drug Eluting Balloon |
|---|---|
| Death | 3 |
Analysis population for the primary outcome, as defined in the registry: The number of participants analyzed includes subjects who were available at that time of analysis
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 | Drug Eluting Balloon |
|---|---|---|
| Participants analysed | 51 | |
| Age, Continuous | years | 69.2 (SD 11.2) |
| Sex/Gender, Customized: Male | Participants | 38 |
| Sex/Gender, Customized: Female | Participants | 13 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 5 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 28 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 18 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 6 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 27 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 18 |
| Prior Percutaneous coronary revascularization (Prior PCI) | Participants | 51 |
6. Primary Endpoint
The registry lists the primary outcome as The Primary Safety Endpoint for the CVT-ISR Study: Freedom From Target Lesion Failure (TLF) Rate, measured over 6 months post-index procedure.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the freedom-from-target-lesion-failure rate at 6 months post-index procedure. Target lesion failure is a composite of cardiovascular death, target vessel myocardial infarction, and clinically driven target lesion revascularization. The outcome unit is participants, and the registry describes the measure as a count of participants. Its population description says that the number analyzed includes subjects available at the time of analysis.
A composite endpoint combines multiple event types into a single measure. General explanation: this approach can capture more than one clinically important way an unfavorable outcome might occur, rather than limiting assessment to a single event. It also means the composite result does not, by itself, show how much each component contributed. Component-specific counts or rates would be needed to understand that distribution.
Freedom from target lesion failure is used as a safety endpoint because it summarizes whether participants experienced any of the defined events during the stated follow-up period. Interpretation depends on the exact component definitions, follow-up, and analysis population. The registry record does not report a numerical primary-endpoint result, the component results, or the number available for this endpoint analysis. Thus, the endpoint definition is clear, but the observed rate and its precision cannot be assessed from the reported information.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes a first-in-human, single-group study with enrollment of 51 participants and a primary safety endpoint at 6 months post-index procedure. It identifies the intervention and defines target lesion failure, but it does not report the observed freedom-from-target-lesion-failure result. Without that result, the primary endpoint cannot be quantified or assessed for precision from the registry record.
The record lists 11 outcome measures and no analyses. Although it names secondary outcomes such as target lesion failure, target vessel failure, revascularization, access-site complications, and measures of success, their numerical results are not reported in the registry record. The endpoint titles alone do not establish how often events occurred or whether outcomes met any target.
The available safety figures describe participants in the Drug Eluting Balloon group. Serious adverse events affected 22 of 51 participants at risk, and other adverse events affected 10 of 51 participants at risk. The record also lists 3 deaths. These counts describe events recorded in the group; they do not establish that the device caused those events. The listed serious-event terms include acute coronary syndrome and angina pectoris, each reported as 7.8%; acute myocardial infarction and adult failure to thrive, each reported as 5.9%; angina unstable at 3.9%; and cardiac disorder at 2.0%. The registry information does not make clear from these figures alone how terms overlap within participants or how events relate to treatment.
General explanation: a point estimate describes the observed value of an outcome, while a confidence interval describes the range of values compatible with the data under the method used. Neither a point estimate nor an interval for the primary endpoint is reported, so its statistical precision cannot be evaluated. Likewise, an event count is informative about the recorded burden but cannot substitute for a comparative estimate.
Because no comparator is listed and allocation is NA, the study does not support a direct estimate of how outcomes differ between the balloon and another treatment. The sample-size assumptions described for planning illustrations use equal allocation between two arms and an effect defined as a fraction of the observed effect. Such planning calculations are not evidence of the trial’s own design or of observed power. They should not be interpreted as a treatment comparison observed in this single-group study.
9. Statistical Methods Explained
The registry classifies the outcome information as binary, with the meaning stated as participants with an event, in counts. For the primary endpoint, the named outcome is freedom from target lesion failure, and the measure unit is participants. The definition combines cardiovascular death, target vessel myocardial infarction, and clinically driven target lesion revascularization. The specified timeframe is 6 months post-index procedure.
What does a composite endpoint convey?
General explanation: a composite endpoint treats the occurrence of any listed component as meeting the composite event definition. This can be useful when the study is interested in a broader outcome made up of several clinically relevant event types. However, a single composite summary can conceal differences among components: one component may occur more often than another, or components may differ in clinical meaning. Component-level results help readers understand what is driving the overall measure. Those numerical results are not reported in the registry record for this study.
What does a participant count mean?
The registry describes the primary measure as a count of participants and says the analyzed number includes subjects available at the time of analysis. General explanation: participant counts are the number of people meeting an outcome definition, rather than a measure of event timing or repeated event burden. A count is most interpretable alongside the number assessed and the observation period. The registry record does not report the number available for the primary analysis or a numerical primary-endpoint count, so the observed frequency cannot be reconstructed from the record.
What can be inferred without a comparator?
The model is single-group, with allocation recorded as NA. General explanation: an estimate within a treated group describes outcomes in that group, but a comparative treatment effect requires a relevant comparison group and a method for estimating the contrast. In a single-group study, observed events may reflect multiple influences, including the underlying condition and the clinical course, as well as any effect of the intervention. The design listed in the registry does not provide a randomized comparator for separating these influences.
How should planning calculations be read?
The planning illustration assumptions state a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect to detect defined as a stated fraction of the observed effect. The assumptions say that non-time-to-event illustrations give participants per arm, while time-to-event illustrations give total events. General explanation: a sample-size calculation is conditional on its assumptions about the effect to detect, error rate, allocation, and statistical method. It describes a planning scenario, not the number of participants who experienced an outcome and not the power observed after the study. In this record, the trial itself is single-group, so the two-arm planning assumptions should not be mistaken for its registered design. Numerical sample-size results or further design justification are not reported in the registry record.
What information is missing for statistical assessment?
The registry lists no analyses. It does not report numerical estimates for the primary endpoint, confidence intervals, component results, or the number available for the primary analysis. General explanation: confidence intervals communicate uncertainty around an estimate, while an analysis description clarifies how the estimate was produced. Without these items, readers cannot assess the endpoint’s magnitude, precision, or sensitivity to analysis choices from this record. The absence of a reported analysis plan also means the record does not establish whether or how adjustments, subgroup analyses, or interim analyses were intended.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 11 outcome measures, including a primary safety endpoint and secondary outcomes addressing target lesion failure, target vessel failure, revascularization, vascular access site complications, lesion success, technical success, and clinical success per subject. It lists no analyses. A statistical plan describing how the outcomes were analyzed, or how the primary and secondary outcomes were prioritized in testing, is not reported in the registry record.
General explanation: when several outcomes are examined, the chance of at least one apparently unusual result can increase if each is tested separately without accounting for the number of tests. Methods for handling multiplicity may define a primary outcome, adjust testing, or treat secondary results as descriptive. The record does not state which approach was used. No significance tests or numerical outcome results are listed, so multiplicity-adjusted or unadjusted statistical conclusions cannot be assessed.
The primary endpoint population is described as participants available at the time of analysis. The number available and the handling of participants with missing follow-up information are not reported in the registry record. It is therefore not possible to determine how many of the 51 enrolled participants contributed to the endpoint or whether missing observations were excluded, imputed, or handled by another method. The record also does not describe a broader analysis population, such as an intention-to-treat population, or rules for inclusion in analysis.
General explanation: missing outcome data can affect both the amount of information and the interpretation of an estimate, particularly if availability is related to participants’ outcomes. Without the number and reasons for unavailable observations, the potential impact cannot be evaluated. No assumptions about missing data or analysis populations should be inferred from the endpoint description 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 |
|---|---|---|---|
| Drug Eluting Balloon | 22 | 51 | 43.1% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Drug Eluting Balloon | 3 of 51 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Drug Eluting Balloon | 10 of 51 |
Most frequent serious adverse event terms
| Event term | Organ system | Drug Eluting Balloon |
|---|---|---|
| Acute coronary syndrome | Cardiac disorders | 4 of 51 |
| Angina pectoris | Cardiac disorders | 4 of 51 |
| Acute myocardial infarction | Cardiac disorders | 3 of 51 |
| Adult failure to thrive | General disorders | 3 of 51 |
| Angina unstable | Cardiac disorders | 2 of 51 |
| Cardiac disorder | Cardiac disorders | 1 of 51 |
| Cardiac failure | Cardiac disorders | 1 of 51 |
| Coronary artery stenosis | Cardiac disorders | 1 of 51 |
| Myocardial infarction | Cardiac disorders | 1 of 51 |
| Myocardial ischemia | Cardiac disorders | 1 of 51 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Drug Eluting Balloon |
|---|---|---|
| Chest pain | General disorders | 5 of 51 |
| Pain | General disorders | 4 of 51 |
| Vascular stent restenosis | Vascular disorders | 3 of 51 |
Serious events with the highest arm-level rate: acute coronary syndrome (7.8%), angina pectoris (7.8%), acute myocardial infarction (5.9%), adult failure to thrive (5.9%), angina unstable (3.9%).
For the Drug Eluting Balloon group, the registry records 22 participants affected by serious adverse events among 51 at risk, and 10 participants affected by other adverse events among 51 at risk. It also records 3 deaths. These are counts reported for the group; the registry information does not establish that the events or deaths were caused by the device or the procedure. It does not specify from these figures whether deaths overlap with the adverse-event counts.
The listed serious-event terms include acute coronary syndrome and angina pectoris, each at 7.8%; acute myocardial infarction and adult failure to thrive, each at 5.9%; angina unstable at 3.9%; and cardiac disorder at 2.0%. These percentages are reproduced as recorded. They should not be added together: the registry record does not establish that the terms are mutually exclusive, and a participant may be represented by more than one event term.
General explanation: adverse-event summaries describe events recorded during a study and are not, by themselves, estimates of causal risk. Interpretation also depends on definitions, timing, follow-up, severity assessment, and attribution procedures. Further details on those points are not reported in the registry record. With no listed comparator, these counts do not allow a direct comparison of safety between treatments.
12. What the Result Does, and Does Not, Mean
The record establishes that this was a completed, first-in-human, single-group study of a drug-eluting balloon for in-stent restenosis, with enrollment of 51 participants. It defines a primary safety endpoint based on freedom from target lesion failure at 6 months post-index procedure and lists additional clinical outcomes. It also records adverse-event counts and deaths in the intervention group.
It does not report the numerical primary endpoint result or numerical results for the listed secondary outcomes. Consequently, the record does not show the observed rate of freedom from target lesion failure, the component events contributing to that endpoint, or the precision of an estimate. The available adverse-event counts provide descriptive safety information but do not establish causation.
General explanation: a study result is most informative when the outcome estimate is presented with its denominator, follow-up context, and an indication of uncertainty. A comparison between interventions also requires a suitable comparator and an analysis designed to estimate the difference. Here, no comparator is listed, and allocation is NA; the design therefore cannot directly establish comparative effects.
The registry’s planning assumptions should be kept separate from observed evidence. They describe an illustration using equal allocation between two arms, a two-sided significance level of 0.05, a normal approximation, and effects defined as fractions of the observed effect. These assumptions do not change the registered single-group design and do not represent observed power. The results needed to judge the primary endpoint’s magnitude and precision are not reported in the registry record.
Overall, the record is informative about the study’s intent, intervention, endpoint definition, and selected safety counts. It is insufficient to determine the numerical primary safety outcome or to draw a comparative conclusion about the intervention.
13. Why This Trial Matters Statistically
This study is statistically notable as a first-in-human evaluation of a device for coronary in-stent restenosis. Early clinical investigations can provide descriptive information about how a device is studied and what outcomes are tracked. The record identifies safety and inhibition of restenosis as goals and defines a primary safety endpoint that combines cardiovascular death, target vessel myocardial infarction, and clinically driven target lesion revascularization.
The design also illustrates the interpretive limits of single-group evidence. Without a comparator, outcome counts describe the enrolled group but do not estimate how outcomes differ from those under another treatment. This distinction is particularly important when a study’s aim includes assessment of safety and restenosis inhibition: the endpoint definition alone is not evidence of the observed result, and a descriptive count is not a comparative effect estimate.
The registry lists 11 outcome measures but no analyses and does not report numerical primary or secondary outcome results. This makes the record useful for understanding the study question and registered outcome framework, while limiting assessment of effect magnitude, precision, and the contribution of endpoint components. The safety figures offer descriptive event information, but they do not establish attribution or comparative safety.
General explanation: transparent reporting of analysis populations, missing-data handling, estimates, and uncertainty helps readers distinguish a study’s design from its findings. In this record, the primary population is described in terms of participants available at analysis, but the number available is not reported. The absence of these details is statistically consequential because it limits assessment of how representative the analyzed participants were and how precisely outcomes were estimated.
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 limitation for interpreting this study from its registry record is that the numerical primary endpoint result is not reported. The record names freedom from target lesion failure at 6 months post-index procedure and defines its components, but gives no observed count or rate, no component-level results, and no uncertainty estimate. Numerical results for the listed secondary outcomes are also not reported.
The single-group model and absence of a listed comparator limit what can be concluded about comparative outcomes. Allocation is NA, so the record does not describe randomized assignment. The study can be read as a description of outcomes among participants treated with the drug-eluting balloon, not as a controlled estimate of differences between treatments.
Although enrollment is 51, the primary population is defined as subjects available at the time of analysis, and the number available is not reported. The registry record does not explain missing-data handling, analysis-population rules, endpoint adjudication, or the duration of follow-up beyond the primary endpoint’s stated timeframe. It also does not report an analysis plan, multiplicity approach, or numerical analyses.
The safety figures do not include enough detail to determine event attribution, overlap between event terms, or whether deaths are included among the adverse-event counts. The registry lists 11 outcome measures but no analyses, which further limits evaluation of how the outcomes were assessed and prioritized. These limitations concern what can be concluded from the registry record; they do not establish that additional information is unavailable elsewhere.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: CVT-ISR First in Human Trial for Coronary In-Stent Restenosis — NCT05731700.
- Registry record last updated 2026-05-15; status last verified 2026-04.
- Results first posted 2025-05-15.
- 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
NCT05731700 is a completed, first-in-human, single-group study sponsored by Abbott Medical Devices. The registry lists enrollment of 51 participants and an intervention identified as a Drug Eluting Balloon for a single in-stent restenosis coronary artery lesion. The primary safety endpoint is freedom from target lesion failure at 6 months post-index procedure, with target lesion failure defined by cardiovascular death, target vessel myocardial infarction, and clinically driven target lesion revascularization.
The record lists 11 outcome measures and no analyses. It reports safety counts for the intervention group, including 22 participants affected by serious adverse events and 10 affected by other adverse events among 51 at risk, along with 3 deaths. The numerical result for the primary endpoint and results for the secondary outcomes are not reported in the registry record. With no comparator listed, the study design does not provide a direct comparative treatment estimate.