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 Pharmacokinetic, Pharmacodynamic, Safety, and Efficacy Study of Rivaroxaban for Thromboprophylaxis in Pediatric Participants 2 to 8 Years of Age After the Fontan Procedure (NCT02846532), a randomized phase 3 study. The primary outcome is Percentage of Participants With Any Thrombotic Event (Venous or Arterial and Symptomatic or Asymptomatic).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02846532 |
| Phase | Phase 3 |
| Condition | Thrombosis |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 112 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Janssen Research & Development, LLC |
| Results posted | Yes |
2. Clinical Question
Population
Children aged 2 to 8 years with single ventricle physiology who had completed the Fontan procedure within 4 months before enrollment. Part A characterized pharmacokinetic and pharmacodynamic profiles after rivaroxaban. The primary endpoint population included participants in Part A who received at least 1 dose of study drug and participants in Part B who were randomized and received at least 1 dose.
Intervention
Rivaroxaban was studied for thromboprophylaxis. The study description specifies twice-daily administration in Part B, with exposure matched to rivaroxaban 10 mg once daily in adults. The study also characterized single and multiple-dose profiles in Part A.
Comparator
Part B compared rivaroxaban with acetylsalicylic acid, also called ASA or aspirin in the registry record. ASA was described as once daily at approximately 5 mg/kg. The study was active-controlled and open-label.
Primary question
The primary endpoint was the percentage of participants with any thrombotic event, including venous or arterial events and symptomatic or asymptomatic events, through up to 12 months. The registry record describes this endpoint but does not report the result or an estimate comparing the treatment groups. It therefore does not establish from the posted primary outcome whether event frequencies differed between groups.
3. Trial Design
This was a Phase 3, randomized, open-label, active-controlled, parallel study of rivaroxaban in pediatric participants aged 2 to 8 years after the Fontan procedure. The registry record gives an enrollment of 112 and lists the study status as completed. The recorded start date is 2016-11-16, and the primary completion date is 2020-07-16.
The study description separates its objectives into Part A and Part B. Part A was intended to characterize single and multiple-dose pharmacokinetic and pharmacokinetic/pharmacodynamic profiles after oral rivaroxaban in children with single ventricle physiology who had completed the Fontan procedure within 4 months before enrollment. Part B evaluated safety and efficacy for thromboprophylaxis, comparing twice-daily rivaroxaban with once-daily acetylsalicylic acid. The description states that the rivaroxaban exposure was matched to rivaroxaban 10 mg once daily in adults and that acetylsalicylic acid was given at approximately 5 mg/kg.
Randomization is listed for the study, and Part B participants in the primary endpoint population had to be randomized and receive at least 1 dose of study drug. The registry record does not report the allocation sequence, randomization ratio, stratification factors, or details of how treatment assignment was implemented. Masking is listed as none, so the trial was open-label rather than blinded. The registry record does not report further operational details about treatment delivery or adherence.
The active-control design compares two study regimens rather than comparing rivaroxaban with no treatment. The parallel model indicates that participants were assigned to treatment groups rather than being described as crossing between treatments. The record does not provide enough detail to infer additional design features or to reconstruct the full protocol. The stated enrollment is not itself an outcome result and does not identify the number of participants included in each treatment group.
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 | Rivaroxaban (Part A) | Rivaroxaban (Part B) | Aspirin (Part B) |
|---|---|---|---|
| STARTED | 12 | 66 | 34 |
| COMPLETED | 11 | 63 | 33 |
| NOT COMPLETED | 1 | 3 | 1 |
Reasons for not completing this period:
| Reason | Rivaroxaban (Part A) | Rivaroxaban (Part B) | Aspirin (Part B) |
|---|---|---|---|
| Lost to Follow-up | 0 | 1 | 1 |
| Withdrawal by Subject | 1 | 2 | 0 |
Analysis population for the primary outcome, as defined in the registry: Full analysis set included all participants in Part A who received at least 1 dose of study drug and all participants in Part B who were randomized and received at least 1 dose of study drug.
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 | Rivaroxaban (Part A) | Rivaroxaban (Part B) | Aspirin (Part B) | Total |
|---|---|---|---|---|---|
| Participants analysed | 12 | 66 | 34 | 112 | |
| Age, Continuous | years | 2.5 (SD 0.67) | 4.1 (SD 1.74) | 4.2 (SD 1.8) | 3.9 (SD 1.74) |
| Sex: Female, Male: Female | Participants | 5 | 30 | 11 | 46 |
| Sex: Female, Male: Male | Participants | 7 | 36 | 23 | 66 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 | 22 | 11 | 34 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 11 | 42 | 19 | 72 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 2 | 4 | 6 |
| Race/Ethnicity, Customized: American Indian or Alaska Native | Participants | 0 | 0 | 0 | 0 |
| Race/Ethnicity, Customized: Asian | Participants | 0 | 14 | 7 | 21 |
| Race/Ethnicity, Customized: Black or African American | Participants | 3 | 8 | 1 | 12 |
| Race/Ethnicity, Customized: Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 | 0 |
| Race/Ethnicity, Customized: White | Participants | 8 | 40 | 20 | 68 |
| Race/Ethnicity, Customized: More than one race | Participants | 0 | 0 | 0 | 0 |
| Race/Ethnicity, Customized: Unknown or Not Reported | Participants | 0 | 2 | 3 | 5 |
| Race/Ethnicity, Customized: Other | Participants | 1 | 2 | 3 | 6 |
| Region of Enrollment: ARGENTINA | Participants | 0 | 5 | 1 | 6 |
| Region of Enrollment: BELGIUM | Participants | 0 | 5 | 4 | 9 |
| Region of Enrollment: BRAZIL | Participants | 0 | 7 | 10 | 17 |
| Region of Enrollment: CANADA | Participants | 0 | 3 | 3 | 6 |
| Region of Enrollment: JAPAN | Participants | 0 | 8 | 1 | 9 |
| Region of Enrollment: MALAYSIA | Participants | 0 | 5 | 5 | 10 |
| Region of Enrollment: MEXICO | Participants | 0 | 6 | 2 | 8 |
| Region of Enrollment: NETHERLANDS | Participants | 0 | 1 | 0 | 1 |
| Region of Enrollment: SPAIN | Participants | 5 | 1 | 0 | 6 |
| Region of Enrollment: UNITED STATES | Participants | 7 | 25 | 8 | 40 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Participants With Any Thrombotic Event (Venous or Arterial and Symptomatic or Asymptomatic), measured over Up to 12 months.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | percentage of participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint was the percentage of participants with any thrombotic event, with follow-up stated as up to 12 months. It included events that were venous or arterial and symptomatic or asymptomatic. The registry definition covered a new thrombotic burden in the cardiovascular system detected by routine surveillance or clinically indicated imaging, as well as a clinical event strongly associated with thrombus. Examples named in the record include cardioembolic stroke and pulmonary embolism; the event categories also included ischemic stroke, venous thrombosis, arterial or intracardiac thrombosis, and other thrombosis.
This endpoint is used to describe how often participants experienced a broadly defined thrombotic event during follow-up. Counting both imaging-detected and clinically apparent events can capture events that might not have produced symptoms, while also making the endpoint dependent on surveillance and clinical imaging. The registry record does not report endpoint adjudication procedures, the specific event-counting rules, or the observed endpoint results.
The outcome is expressed as a percentage of participants, a binary-outcome summary: each participant is classified according to whether an event occurred during the stated period. That summary does not, by itself, describe when an event occurred, how many events an individual experienced, or the severity of each event. The record lists the endpoint and its definition but does not report the number of participants with events or a treatment-group comparison.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the primary outcome as the percentage of participants with any thrombotic event up to 12 months. It does not report the observed outcome values, event counts, treatment-group percentages, an effect estimate, or a confidence interval for this endpoint. As a result, the posted record does not support a numerical interpretation of how the primary outcome differed between rivaroxaban and acetylsalicylic acid.
The study was designed to evaluate rivaroxaban in relation to an active comparator and included both pharmacokinetic/pharmacodynamic and safety objectives. Its randomized, parallel design is relevant to how the comparison was structured, while its open-label status means masking was not used. Neither the design labels nor the planned objectives substitute for posted outcome results. They cannot establish the direction, size, or precision of a treatment-group difference.
The primary endpoint combines several kinds of thrombotic events, including events found on surveillance imaging and events associated with clinical presentation. That breadth is part of the registry definition, but the record does not provide event-level results or a breakdown by event type, symptom status, or detection method. It is therefore not possible from the posted primary outcome to determine which component contributed to any group-level pattern.
The registry lists 36 outcome measures, but the primary endpoint's results are not included in the registry record recorded for this analysis. The registry record also indicates no analysis results. Accordingly, there is no posted primary comparison to interpret in terms of statistical evidence or clinical magnitude. No conclusion about whether one regimen had more or fewer thrombotic events can be drawn from the information recorded for this endpoint.
The adverse-event information is separate from the primary thrombotic endpoint. The registry reports serious adverse event and other adverse event counts for the listed groups, but these figures do not fill the gap in the primary endpoint results. They also should not be treated as a complete account of benefit and harm: the registry record does not supply a comparative statistical analysis, uncertainty estimates, or a full narrative of event timing and clinical context.
Interpretation is also limited by what is not reported. The registry record does not state a statistical analysis plan, the planned handling of missing primary endpoint data, a method for controlling multiple comparisons, or a sample-size justification. These omissions prevent assessment of whether the analysis followed a prespecified approach. They do not prove that such methods were absent from the protocol; they mean they are not reported in the registry record.
9. Statistical Methods Explained
What does the design describe?
General: In a randomized trial, treatment assignment is determined through a random process, which is intended to reduce systematic differences between groups at the start of a comparison. A parallel design assigns participants to a treatment group for the study rather than describing a sequence in which participants receive each treatment. An active-controlled study compares an intervention with another treatment rather than with no active comparator. These general properties help explain the design labels, but they do not provide the allocation details or analysis procedures for this particular trial.
The registry record identifies the study as randomized, parallel, active-controlled, and open-label. It does not report the randomization method, allocation ratio, stratification, or concealment procedures. Open-label means treatment assignment was not masked according to the record. The record does not describe whether endpoint assessors or other personnel were separately blinded.
How should the primary endpoint be understood?
General: A binary participant-level endpoint records whether each participant experienced an event during a defined period. A percentage summarizes the proportion of participants classified as having an event, but it does not represent the number of separate events if one participant can experience more than one. It also does not show the timing of events. The registry record defines the primary outcome as the percentage of participants with any thrombotic event through up to 12 months, but it does not report the observed percentages or counts.
The definition includes imaging-detected and clinically recognized thrombosis, and it spans several event categories. The record does not report whether events were independently adjudicated, how recurrent events were handled, or how incomplete follow-up affected classification. Those details matter when assessing how consistently the endpoint was measured and analyzed.
What does a confidence interval communicate?
General: A confidence interval expresses the statistical uncertainty around an estimate under the assumptions of the analysis. Its width reflects precision: a narrower interval indicates greater precision, while a wider interval indicates less precision. An interval can also show which values are reasonably compatible with the data and method. The registry record does not report a confidence interval or an effect estimate for the primary endpoint, so the precision of a treatment comparison cannot be assessed from the posted outcome information.
A p-value, when reported, measures how incompatible the observed data are with a specified statistical null model, under the model's assumptions. It does not measure the probability that a treatment works, nor does it quantify the size or clinical importance of an effect. No primary endpoint p-value is reported in the registry record. The listed significance level of two-sided 0.05 belongs to the stated planning illustration assumptions, not to a reported result for the trial's primary endpoint.
What can the sample-size planning approach establish?
General: A sample-size calculation is a planning tool that describes the number of participants or events a design would require under chosen assumptions. It is not evidence that an observed effect exists, and it is not an observed measure of power after a study is complete. The stated planning approach is an illustration based on the observed effect, with equal allocation, a normal approximation, and a two-sided significance level of 0.05; it considers effects stated as fractions of the observed effect. The registry record does not report the actual numerical planning illustrations or the trial's own design justification. The assumptions therefore cannot be used to infer the protocol's planned sample size or the adequacy of the enrolled number.
For binary outcomes, the size of a planning estimate depends on the assumed event frequency and the effect targeted, as well as the selected statistical assumptions. General: If the event frequency differs from the assumption, the achieved precision and ability to detect a difference can also differ. Because the primary endpoint results and numerical planning illustrations are not reported in the record used for this analysis, no such comparison can be made for this trial.
What can be learned from the safety summaries?
The registry reports serious adverse event counts and other adverse event counts for the listed groups, together with the numbers at risk for those summaries. These are descriptive counts, not adjusted comparisons. General: Counts and percentages can describe the frequency of recorded events, while comparative inference also requires a defined estimand, an analysis method, and an account of uncertainty. The registry record does not give an inferential safety comparison or confidence intervals for the reported counts.
The record separately lists serious adverse event terms with percentages. It does not specify in the recorded information the denominators or group assignment for those term percentages. They should therefore be read as the listed descriptive values and not as evidence of a treatment-group difference. The listed zero deaths are also limited to the recorded group summaries and do not replace a broader safety analysis.
Which analysis details are not reported?
The statistical analysis plan, missing-data methods, multiplicity strategy, and details of endpoint analysis are not reported in the registry record. The record does not provide a primary outcome model, a prespecified effect measure, a method for accounting for follow-up duration, or sensitivity analyses. These details cannot be reconstructed from the study design labels alone.
The stated primary analysis population includes participants in Part A who received at least 1 dose and participants in Part B who were randomized and received at least 1 dose. General: Defining an analysis population clarifies which participants contribute to an estimate, but the exact handling of participants with missing measurements or incomplete follow-up remains important. The registry record does not report that handling. Consequently, the available description supports an account of the intended population and endpoint, but not a full independent reconstruction of the statistical analysis.
10. Multiplicity, Missing Data and Analysis Populations
The registry record does not report a method for addressing multiplicity. It lists 36 outcome measures, but does not state which outcomes were designated for confirmatory testing, whether a hierarchy was used, or whether the chance of false-positive findings across multiple tests was controlled. No analysis results are listed for the primary endpoint. Without a reported analysis plan and results, the relationship among the listed outcomes and any formal hypothesis tests cannot be assessed.
Missing-data procedures are also not reported in the registry record. The primary endpoint follows participants for up to 12 months, but the record does not explain how incomplete follow-up, missing imaging, withdrawal, or other unavailable endpoint information was handled. It does not report sensitivity analyses for missing outcomes. General: Missing-data methods matter because estimates can depend on how participants without fully observed outcomes are treated. No assumption about the effect of missingness is justified by the recorded information.
The primary endpoint population is defined as the full analysis set: Part A participants who received at least 1 dose and Part B participants who were randomized and received at least 1 dose. The registry record does not report a separate per-protocol population or provide a detailed account of analysis exclusions. It also does not report the numbers contributing to each primary endpoint analysis.
The record indicates no posted analysis results. That absence prevents assessment of the multiplicity strategy, missing-data handling, and consistency between the planned and reported analyses. These methods may have been described elsewhere, but they are not reported in 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 |
|---|---|---|---|
| Rivaroxaban (Part A) | 6 | 12 | 50.0% |
| Rivaroxaban (Part B) | 19 | 64 | 29.7% |
| Aspirin (Part B) | 8 | 34 | 23.5% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Rivaroxaban (Part A) | 0 of 12 |
| Rivaroxaban (Part B) | 0 of 64 |
| Aspirin (Part B) | 0 of 34 |
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 |
|---|---|
| Rivaroxaban (Part A) | 11 of 12 |
| Rivaroxaban (Part B) | 48 of 64 |
| Aspirin (Part B) | 26 of 34 |
Most frequent serious adverse event terms
| Event term | Organ system | Rivaroxaban (Part A) | Rivaroxaban (Part B) | Aspirin (Part B) |
|---|---|---|---|---|
| Pleural Effusion | Respiratory, thoracic and mediastinal disorders | 2 of 12 | 9 of 64 | 2 of 34 |
| Pneumonia | Infections and infestations | 1 of 12 | 1 of 64 | 1 of 34 |
| Influenza | Infections and infestations | 0 of 12 | 1 of 64 | 1 of 34 |
| Laryngitis | Infections and infestations | 1 of 12 | 1 of 64 | 0 of 34 |
| Seizure | Nervous system disorders | 0 of 12 | 1 of 64 | 1 of 34 |
| Cardiac Failure Congestive | Cardiac disorders | 0 of 12 | 1 of 64 | 0 of 34 |
| Supraventricular Tachycardia | Cardiac disorders | 0 of 12 | 1 of 64 | 0 of 34 |
| Periorbital Oedema | Eye disorders | 0 of 12 | 1 of 64 | 0 of 34 |
| Pyrexia | General disorders | 1 of 12 | 0 of 64 | 0 of 34 |
| Swelling Face | General disorders | 0 of 12 | 0 of 64 | 1 of 34 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Rivaroxaban (Part A) | Rivaroxaban (Part B) | Aspirin (Part B) |
|---|---|---|---|---|
| Pyrexia | General disorders | 0 of 12 | 16 of 64 | 7 of 34 |
| Nasopharyngitis | Infections and infestations | 1 of 12 | 14 of 64 | 6 of 34 |
| Upper Respiratory Tract Infection | Infections and infestations | 2 of 12 | 9 of 64 | 5 of 34 |
| Cough | Respiratory, thoracic and mediastinal disorders | 0 of 12 | 12 of 64 | 4 of 34 |
| Vomiting | Gastrointestinal disorders | 3 of 12 | 9 of 64 | 3 of 34 |
| Ecchymosis | Skin and subcutaneous tissue disorders | 0 of 12 | 6 of 64 | 5 of 34 |
| Epistaxis | Respiratory, thoracic and mediastinal disorders | 0 of 12 | 6 of 64 | 3 of 34 |
| Rash | Skin and subcutaneous tissue disorders | 2 of 12 | 4 of 64 | 2 of 34 |
| Diarrhoea | Gastrointestinal disorders | 2 of 12 | 3 of 64 | 2 of 34 |
| Otitis Media | Infections and infestations | 0 of 12 | 4 of 64 | 3 of 34 |
Serious events with the highest arm-level rate: pleural effusion (16.7%), pyrexia (8.3%), bronchitis (8.3%), laryngitis (8.3%), pneumonia (8.3%).
The registry lists serious adverse event summaries for Rivaroxaban (Part A), Rivaroxaban (Part B), and Aspirin (Part B). For serious adverse events, the record gives 6 affected among 12 at risk in Rivaroxaban (Part A), 19 among 64 at risk in Rivaroxaban (Part B), and 8 among 34 at risk in Aspirin (Part B). For other adverse events, it gives 11 among 12 at risk in Rivaroxaban (Part A), 48 among 64 at risk in Rivaroxaban (Part B), and 26 among 34 at risk in Aspirin (Part B). The listed deaths are 0 for each group.
These figures are descriptive counts. Part A and Part B are distinct study parts, and the registry does not present Part A as a randomized comparison with aspirin. The Part B counts alone do not provide an adjusted or uncertainty-qualified comparison. The registry record does not report event timing, duration, severity grading beyond the serious-event classification, or a statistical analysis of between-group safety differences.
The record also lists serious adverse event terms with the following percentages: Pleural Effusion, 16.7%; Pyrexia, 8.3%; Bronchitis, 8.3%; Laryngitis, 8.3%; Pneumonia, 8.3%; and Viral Infection, 8.3%. The denominator and group assignment for these term percentages are not reported in the registry record. These values should be interpreted as descriptive entries, not as treatment-specific rates or comparative evidence.
12. What the Result Does, and Does Not, Mean
The study record describes a randomized comparison in Part B of rivaroxaban and acetylsalicylic acid for thromboprophylaxis in children aged 2 to 8 years after the Fontan procedure. It also describes pharmacokinetic and pharmacodynamic characterization in Part A and includes safety outcomes. Those objectives establish what the study set out to examine, not what its primary endpoint results showed.
The primary outcome is clearly defined as the percentage of participants with any thrombotic event through up to 12 months, including events detected by imaging as well as clinical events. However, the registry record does not report the primary outcome values, event counts, comparative estimate, or confidence interval. The posted information therefore cannot establish the direction or magnitude of a difference between treatment groups, or how precisely such a difference was estimated.
The safety summaries provide counts of participants with serious and other adverse events and list deaths for each recorded group. They offer descriptive information, but they do not include a comparative statistical analysis or enough detail to evaluate event timing and context. The serious-event terms are accompanied by percentages, but their denominators and group assignments are not reported. These limitations prevent those entries from serving as a complete comparative safety assessment.
General: A trial result is interpreted by considering the outcome definition, population, size and precision of any estimate, analysis methods, and limitations in follow-up or measurement. Here, the registry describes some of the design and population but does not report the primary endpoint result or the analysis details needed for a full statistical assessment. The record supports a description of the question and design, but not a conclusion about whether either treatment had a lower thrombotic event frequency or a different overall safety profile.
The enrollment of 112 and the completed status describe the study record, not the number analyzed for the primary outcome or the completeness of follow-up. No inference about the trial's statistical power or the certainty of its results can be drawn from enrollment alone. The stated sample-size approach is explicitly a planning illustration and does not replace the missing primary outcome analysis.
13. Why This Trial Matters Statistically
This study is statistically notable for combining two kinds of evidence in a pediatric post-Fontan setting: pharmacokinetic and pharmacodynamic characterization, and an active-controlled evaluation of safety and efficacy. These objectives address different questions. Characterizing drug exposure and response is not the same as estimating a treatment-group difference in clinical events, so results for one objective would not automatically answer the other.
The primary endpoint also illustrates a measurement choice with statistical consequences. It combines symptomatic and asymptomatic events and allows detection through routine surveillance or clinically indicated imaging. General: Broader event definitions can capture more kinds of outcomes, but interpretation depends on consistent measurement and clear rules for identifying and counting events. The registry record gives a definition, but does not report adjudication procedures or a breakdown of observed events by type or detection method.
The randomized, open-label, active-controlled design offers a structured comparison in Part B, while the absence of reported primary results limits what can be concluded from the registry record. Statistical interpretation requires both a design description and the corresponding outcome estimates, including their uncertainty. Without the latter, the reader cannot assess the magnitude or precision of a treatment comparison.
The record also highlights why analysis methods matter beyond the treatment assignment. The registry does not report how missing outcomes or multiple outcomes were handled, nor does it give a detailed statistical analysis plan. Those omissions make it difficult to judge how the reported outcome measures would be interpreted together or how robust an estimate would be to incomplete follow-up.
Finally, the distinction between descriptive safety counts and comparative evidence is important. Counts can document how many participants were recorded with events in each group, but they do not alone establish a between-group difference or its precision. The registry information therefore supports careful description of study structure and recorded safety summaries, while leaving the central primary endpoint comparison unresolved.
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 most direct limitation is that the registry record does not report the primary endpoint results. It provides the endpoint definition and timeframe but no event counts, treatment-group percentages, effect estimate, confidence interval, or p-value. The primary question therefore cannot be answered statistically from the posted outcome information.
The endpoint includes several types of thrombotic events and permits identification through surveillance or clinically indicated imaging. The record does not report how events were adjudicated, how recurrent events were counted, or whether surveillance was standardized between groups. It also does not provide a breakdown by event type, symptoms, or detection method. These missing details limit assessment of endpoint consistency and the contribution of different events.
The study was open-label, and the registry record does not describe whether any outcome assessment was blinded. It does not report details of treatment adherence, discontinuation, loss to follow-up, or the number of participants contributing to each endpoint analysis. The stated primary analysis population is defined by study part and receipt of at least 1 dose, but the handling of missing outcomes and exclusions is not reported.
The registry record does not report the statistical analysis plan, multiplicity strategy, or sample-size justification. It lists a planning illustration approach, but no numerical illustration results are available in the registry record for this analysis. The record also provides no primary endpoint analysis results against which to assess the stated planning assumptions.
Safety data are descriptive and do not include uncertainty estimates or a reported comparative analysis. The record does not specify the denominators or treatment-group assignment for the listed serious adverse event term percentages. These limitations do not establish that the underlying trial lacked additional methods or results; they identify what is not reported in the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Pharmacokinetic, Pharmacodynamic, Safety, and Efficacy Study of Rivaroxaban for Thromboprophylaxis in Pediatric Participants 2 to 8 Years of Age After the Fontan Procedure — NCT02846532.
- Registry record last updated 2025-03-30; status last verified 2025-03.
- Results first posted 2022-03-28.
- 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
NCT02846532 is a completed Phase 3 randomized, open-label, active-controlled, parallel study of rivaroxaban for thromboprophylaxis in children aged 2 to 8 years after the Fontan procedure. The registry lists enrollment of 112, a start date of 2016-11-16, and a primary completion date of 2020-07-16. The sponsor is Janssen Research & Development, LLC.
Part A characterized pharmacokinetic and pharmacodynamic profiles after rivaroxaban. Part B evaluated safety and efficacy of rivaroxaban compared with acetylsalicylic acid. The primary endpoint was the percentage of participants with any thrombotic event, including symptomatic or asymptomatic venous or arterial events, through up to 12 months.
The registry record describes the endpoint and gives adverse-event counts, but does not report primary endpoint results or a comparative analysis. It also does not report the statistical plan, multiplicity strategy, or missing-data methods.