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 Effect of Selexipag on Daily Life Physical Activity of Patients With Pulmonary Arterial Hypertension. (NCT03078907), a randomized phase 4 study. The primary outcome is Change From Baseline to Week 24 in Actigraphy Assessed Daily Life Physical Activity (DLPA) for Variables Expressed in Minutes.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03078907 |
| Phase | Phase 4 |
| Condition | Pulmonary Arterial Hypertension |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 108 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Actelion |
| Results posted | Yes |
2. Clinical Question
Population
Participants had pulmonary arterial hypertension. The study included 108 participants, and the primary outcome description specifies a Full Analysis Set that included all participants randomly assigned to a study treatment.
Intervention
Participants assigned to selexipag followed an up-titration schedule from Day 1 to Week 12, aiming for an individualized highest tolerated dose. The stated range was 200 mcg b.i.d. to 1600 mcg b.i.d., in 200 mcg steps, starting at 200 mcg b.i.d.
Comparator
The comparison group received placebo. Its regimen and titration scheme were described as similar to those in the selexipag group, supporting a comparison of assignment to the two study regimens.
Primary question
The primary question was whether assignment to selexipag changed actigraphy-assessed daily-life physical activity from baseline to Week 24, including time spent in non-sedentary activity and moderate-to-vigorous physical activity. The registry record does not report the numerical primary outcome results, so the direction and precision of the observed between-group comparison cannot be assessed from that record.
3. Trial Design
This was a randomized, parallel-group, placebo-controlled phase 4 study in people with pulmonary arterial hypertension. Its official title describes it as multicenter and double-blind. The registry lists quadruple masking, indicating that masking was recorded across four roles or groups; the specific roles are not reported in the registry record. Enrollment was 108. The study is listed as completed, with a start date of 2017-11-08 and a primary completion date of 2020-02-10.
Participants were randomly assigned to selexipag or placebo. The selexipag arm was titrated from Day 1 through Week 12 toward each participant’s individualized highest tolerated dose. The stated range was 200 mcg b.i.d. to 1600 mcg b.i.d., with 200 mcg steps and a starting dose of 200 mcg b.i.d. The placebo regimen and titration scheme were described as similar. Further details about treatment duration, adherence, dose attainment, or treatment discontinuation are not reported in the registry record.
The primary objective was to evaluate physical activity in daily life using a wearable wrist device, with measurement in participants’ real environment. The record also describes electronic patient-reported assessment of pulmonary arterial hypertension symptoms and their impacts. The primary activity endpoint was assessed at baseline and Week 24, using 14 days of data at each period and reporting a mean value. The stated analysis population was the Full Analysis Set, defined as all participants randomly assigned to a study treatment.
Secondary outcomes included the PAH-SYMPACT score, change in WHO functional class, six-minute walk distance, Borg dyspnea score, and NT-proBNP. The registry lists 15 outcome measures and 11 analyses, but the associated analysis details and numerical secondary results 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
| Stage | Selexipag | Placebo |
|---|---|---|
| STARTED | 53 | 55 |
| COMPLETED | 50 | 54 |
| NOT COMPLETED | 3 | 1 |
Reasons for not completing this period:
| Reason | Selexipag | Placebo |
|---|---|---|
| Adverse Event | 2 | 0 |
| Other | 1 | 0 |
| Protocol Violation | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: The Full Analysis Set (FAS) included all participants randomly assigned to a study treatment.
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 | Selexipag | Placebo | Total |
|---|---|---|---|---|
| Participants analysed | 53 | 55 | 108 | |
| Age, Continuous | years | 49 (SD 14.75) | 49.8 (SD 13.63) | 49.4 (SD 14.13) |
| Sex: Female, Male: Female | Participants | 35 | 42 | 77 |
| Sex: Female, Male: Male | Participants | 18 | 13 | 31 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 4 | 3 | 7 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 2 | 0 | 2 |
| Race (NIH/OMB): White | Participants | 44 | 52 | 96 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 3 | 0 | 3 |
| Region of Enrollment: AUSTRIA | participants | 0 | 1 | 1 |
| Region of Enrollment: FRANCE | participants | 2 | 0 | 2 |
| Region of Enrollment: GERMANY | participants | 6 | 5 | 11 |
| Region of Enrollment: IRELAND | participants | 1 | 1 | 2 |
| Region of Enrollment: NORWAY | participants | 0 | 1 | 1 |
| Region of Enrollment: PORTUGAL | participants | 3 | 3 | 6 |
| Region of Enrollment: SWEDEN | participants | 4 | 0 | 4 |
| Region of Enrollment: SWITZERLAND | participants | 0 | 1 | 1 |
| Region of Enrollment: UNITED KINGDOM | participants | 31 | 35 | 66 |
| Region of Enrollment: UNITED STATES | participants | 6 | 8 | 14 |
6. Primary Endpoint
The registry lists the primary outcome as Change From Baseline to Week 24 in Actigraphy Assessed Daily Life Physical Activity (DLPA) for Variables Expressed in Minutes, measured over Baseline and Week 24 (data analysis was done during 14-Days each for Baseline and for Week 24 and mean value reported).
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | minutes |
| Endpoint classification | Continuous Endpoint |
The primary endpoint concerns change from baseline to Week 24 in actigraphy-assessed daily-life physical activity, expressed in minutes. It includes daily time spent in non-sedentary activity and daily time spent in moderate-to-vigorous physical activity. The activity data were collected with a wearable wrist device in participants’ ordinary environment, rather than being limited to a clinic-based activity assessment. Baseline and Week 24 values each used 14 days of data, with a mean value reported for each period.
The endpoint description defines non-sedentary activity using thresholds attributed to Freedson '98 and Koster '16, and defines moderate-to-vigorous physical activity using Freedson '98. The record explains that the cited work relates activity counts from accelerometers to activity categories; it also distinguishes the wrist-worn approach used in the trial from the hip-worn accelerometer ranges discussed in Freedson '98. A positive change from baseline is defined as improvement.
As a general measurement concept, device-based monitoring can characterize activity over ordinary daily routines and across multiple days. It may capture behavior that a single clinic visit would not represent. Interpretation still depends on how activity is classified, how the device is worn, and how usable measurement periods are handled. Those operational details are not fully described in the registry record. Most importantly, the numerical primary outcome estimates and their uncertainty are not reported in the registry record, so the endpoint definition alone does not establish the size or precision of any group difference.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The record establishes the central design question: whether assignment to selexipag, compared with placebo, was associated with change in daily-life activity over the study’s baseline-to-Week 24 assessment. It defines activity in minutes and identifies non-sedentary activity and moderate-to-vigorous physical activity as the primary activity parameters. It also states that positive change from baseline means improvement.
However, the primary outcome results are not reported in the registry record. The primary outcome is described as having several categories or time points and is not reduced to one comparison. As a result, the registry entries available for this analysis do not supply a single treatment-effect estimate, confidence interval, or p-value for the primary question. No conclusion about the magnitude, direction, or statistical precision of the primary comparison can be drawn from the endpoint description alone. The record also does not report a result for each activity parameter, so those components cannot be interpreted separately.
The trial’s randomized, parallel-group design provides a framework for comparing assigned treatments. Randomization is intended, as a general statistical principle, to make treatment groups comparable on average at assignment, although it does not guarantee identical groups in a particular trial. Masking can reduce some opportunities for expectations to influence care, reporting, or assessment. The registry lists quadruple masking, but does not identify the masked roles or explain how masking was maintained. These design features do not replace examination of the actual outcome estimates and their uncertainty.
The registry record identifies the Full Analysis Set as all participants randomly assigned to a study treatment. It does not report the number contributing usable actigraphy data at each assessment, the handling of missing measurements, or the analysis model used to compare groups. Consequently, it is not possible to determine from the record whether the analysis retained all randomized participants in practice or how incomplete device records affected the estimates.
Several secondary outcomes are listed, including patient-reported symptoms and impacts, functional class, six-minute walk distance, Borg dyspnea score, and NT-proBNP. Their names indicate that the study considered more than activity alone, but the registry information does not report their numerical findings or establish how they relate to the primary outcome. The counts of outcome measures and analyses do not by themselves reveal which tests were prespecified as confirmatory, how multiplicity was controlled, or how results were selected for emphasis. Those details are not reported in the registry record.
Accordingly, the available information supports a description of the research question, measurement schedule, and broad design, but not a quantitative judgment about the primary effect. A reader would need the posted numerical results and the analysis details to assess the estimated difference, its uncertainty, and whether the analysis aligned with the intended comparison.
9. Statistical Methods Explained
The registry record describes a randomized, parallel-group comparison of selexipag and placebo. Random assignment is a design method intended to reduce systematic differences between groups at the point of allocation. In general, it supports an interpretation of outcome differences in relation to treatment assignment, provided the analysis and follow-up preserve the benefits of randomization. Randomization does not ensure that the groups are identical in every feature, and the record does not provide baseline characteristics with which to assess their observed balance.
What does the endpoint measure?
The endpoint is a continuous measure expressed in minutes. It concerns change from baseline to Week 24 in daily time spent in non-sedentary activity and moderate-to-vigorous physical activity, assessed by a wearable wrist device. The record says that each assessment period used 14 days of activity data and that a mean value was reported. A continuous outcome retains information about the amount of activity rather than reducing it to a category such as improved or not improved. The endpoint description defines positive change as improvement.
As a general statistical concept, a mean represents the average of measured values in a group or period. A standard deviation describes how dispersed individual measurements are around a mean. The registry identifies the outcome parameter as a mean and the dispersion as a standard deviation, but the actual means, standard deviations, and between-group estimates are not reported in the registry record. Therefore, the amount of variability and the scale of the observed difference cannot be assessed from the record details.
How should a treatment estimate be read?
In a two-arm trial, the key comparison is generally the difference between outcomes under the two assigned groups, interpreted according to the analysis plan and endpoint definition. A confidence interval, when reported, represents a range of values reasonably compatible with the data and the statistical model at its stated confidence level. A narrower interval indicates greater precision than a wider interval, while the interval’s location describes which effect values are compatible with the analysis. A p-value, when reported, measures how incompatible the data are with a specified null hypothesis under the assumptions of the test; it does not measure clinical importance or the probability that a hypothesis is true. These are general explanations, not interpretations of an unreported trial estimate. No primary estimate, confidence interval, or p-value is reported in the registry record.
Why can variability matter?
Activity measures can vary among people and across measurement periods. As a general statistical matter, greater variability can make a group comparison less precise if other aspects of the study are unchanged. Repeated days of monitoring may characterize ordinary activity more fully than a single measurement, but the record does not report how day-to-day variability was modeled or whether all participants contributed the full measurement period. It also does not report the distribution of the activity outcome or whether the analysis addressed unusual values.
Over-dispersion is a general issue in count outcomes when observed variability exceeds what a simple count model assumes. The primary endpoint described in this study is measured in minutes and analyzed as a mean, so the record does not identify over-dispersion as an issue in the primary analysis. If count-based secondary outcomes were analyzed, their model assumptions would need to be assessed from the relevant analysis details; those details are not reported in the registry record.
What does the analysis population mean?
The Full Analysis Set is defined in the record as all participants randomly assigned to a study treatment. Including randomized participants in the analysis is intended, as a general principle, to preserve the treatment-assignment comparison. But a population label does not explain how missing outcome measurements, treatment discontinuation, or other post-randomization events were handled. The registry does not report the actual number included in each primary analysis or the method used to address missing data.
How should planning illustrations be understood?
Sample-size illustrations based on an observed effect are planning calculations, not observed treatment outcomes and not evidence that the trial had a particular probability of detecting an effect. The stated assumptions for the illustrations are a two-sided significance level of 0.05, equal allocation, and a normal approximation; the effect to detect is a stated fraction of the observed effect. The record characterizes these as planning illustrations rather than the trial’s own design calculations. The trial’s original sample-size justification is not reported in the registry record. Such calculations depend on assumptions about the target effect, variability, allocation, and analysis, and changing those assumptions changes the illustration. They should not be read as observed power or as a substitute for the actual estimate and its confidence interval.
The registry record states that the primary outcome has several categories or time points and is not reduced to one comparison. This matters because distinct activity parameters can produce distinct estimates. Without the analysis details, it is not possible to determine which comparison was designated primary for inference or how multiple outcome comparisons were addressed.
10. Multiplicity, Missing Data and Analysis Populations
The study lists multiple outcomes, including two activity parameters, patient-reported symptoms and impacts, functional class, six-minute walk distance, Borg dyspnea score, and NT-proBNP. The registry also lists 15 outcome measures and 11 analyses. These counts indicate that the study record encompasses multiple measurements and analyses, but do not identify which comparisons were considered confirmatory or how results across outcomes were interpreted.
As a general statistical concept, testing multiple outcomes or comparisons can increase the chance that at least one result appears statistically notable by chance. Prespecified testing hierarchies, adjustment procedures, or a clearly defined primary comparison can help manage that issue. The registry does not report a multiplicity adjustment, testing hierarchy, or complete statistical analysis plan. It is therefore not possible to determine how multiplicity was addressed.
The record defines the Full Analysis Set as all randomized participants, but does not explain the treatment of missing actigraphy days, missing Week 24 measurements, incomplete electronic questionnaires, or other missing outcomes. It also does not report whether missingness was addressed by imputation, a model-based approach, or another method. Those details are not reported in the registry record.
The absence of these details limits assessment of whether the analysis population and missing-data procedures were consistent with the randomized comparison. It also prevents evaluation of the robustness of estimates to alternative assumptions about participants without outcome data. These are reporting limitations; they do not establish that a particular method was or was not used.
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 |
|---|---|---|---|
| Selexipag | 3 | 53 | 5.7% |
| Placebo | 6 | 55 | 10.9% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Selexipag | 0 of 53 |
| Placebo | 0 of 55 |
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 |
|---|---|
| Selexipag | 52 of 53 |
| Placebo | 52 of 55 |
Most frequent serious adverse event terms
| Event term | Organ system | Selexipag | Placebo |
|---|---|---|---|
| Atrial Flutter | Cardiac disorders | 1 of 53 | 1 of 55 |
| Right Ventricular Failure | Cardiac disorders | 1 of 53 | 0 of 55 |
| Vision Blurred | Eye disorders | 0 of 53 | 1 of 55 |
| Glossitis | Gastrointestinal disorders | 0 of 53 | 1 of 55 |
| Pneumonia | Infections and infestations | 0 of 53 | 1 of 55 |
| Migraine | Nervous system disorders | 1 of 53 | 0 of 55 |
| Multiple Sclerosis Relapse | Nervous system disorders | 0 of 53 | 1 of 55 |
| Syncope | Nervous system disorders | 0 of 53 | 1 of 55 |
| Pleural Effusion | Respiratory, thoracic and mediastinal disorders | 0 of 53 | 1 of 55 |
| Thyroid Nodule Removal | Surgical and medical procedures | 0 of 53 | 1 of 55 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Selexipag | Placebo |
|---|---|---|---|
| Headache | Nervous system disorders | 41 of 53 | 26 of 55 |
| Diarrhoea | Gastrointestinal disorders | 28 of 53 | 23 of 55 |
| Nausea | Gastrointestinal disorders | 22 of 53 | 15 of 55 |
| Pain in Jaw | Musculoskeletal and connective tissue disorders | 20 of 53 | 5 of 55 |
| Nasopharyngitis | Infections and infestations | 5 of 53 | 14 of 55 |
| Arthralgia | Musculoskeletal and connective tissue disorders | 11 of 53 | 8 of 55 |
| Vomiting | Gastrointestinal disorders | 13 of 53 | 4 of 55 |
| Dizziness | Nervous system disorders | 7 of 53 | 7 of 55 |
| Upper Respiratory Tract Infection | Infections and infestations | 6 of 53 | 6 of 55 |
| Pain in Extremity | Musculoskeletal and connective tissue disorders | 11 of 53 | 1 of 55 |
Serious events with the highest arm-level rate: atrial flutter (1.9%), right ventricular failure (1.9%), migraine (1.9%), vision blurred (1.8%), glossitis (1.8%).
The registry lists serious adverse events among participants at risk in each group. In the selexipag group, 3 of 53 participants were recorded as affected by a serious adverse event; in the placebo group, 6 of 55 were recorded as affected. The record lists 53 and 55 participants at risk, respectively, and reports 0 deaths in each group.
These are observed counts during the registry’s safety reporting period. They do not, on their own, describe the timing, duration, severity beyond the serious-event classification, or causal relationship of events to study treatment. The registry record does not report those details in the information available for this analysis. The counts also do not establish that all participants had the same length of follow-up or exposure.
As a general statistical principle, safety counts should be interpreted in relation to the number of participants at risk and the way events were collected and classified. The listed counts are not a complete description of all potential harms, and they do not determine whether a treatment is safe or unsafe. The record also lists serious-event terms including atrial flutter, right ventricular failure, migraine, vision blurred, glossitis, and pneumonia, with percentages recorded alongside those terms. The registry information does not explain the denominator or detailed event-level context for those listed percentages, so they should not be interpreted as comparative risks without further detail.
12. What the Result Does, and Does Not, Mean
The study addresses a practical measurement question: whether a randomized comparison of selexipag and placebo is associated with a change in activity measured during daily life, rather than only during a clinical assessment. The use of a wrist-worn actigraph and repeated measurement periods is central to that question. The endpoint is defined in minutes and includes non-sedentary activity and moderate-to-vigorous physical activity, with positive change designated as improvement.
The registry record does not report numerical primary outcome results. Therefore, it does not support a conclusion about the direction or magnitude of the primary comparison, the precision of any estimate, or whether the observed results were compatible with no difference. No claim that treatment works or does not work follows from the design description or endpoint definition alone.
The record identifies several secondary outcomes, but their numerical results are also not reported in the available details. Their inclusion shows that the study was designed to assess more than activity, including symptoms and impacts, functional class, walking distance, dyspnea score, and a biomarker. Without estimates and uncertainty for those outcomes, they cannot be used to corroborate or qualify the primary comparison.
Even when numerical results are available, an average change does not describe every participant’s experience. Interpretation depends on the magnitude and precision of the group comparison, the distribution of responses, the analysis population, missing-data handling, and the relevance of the measured difference. Those aspects cannot be resolved from the registry information. The serious adverse event counts are also descriptive and do not establish causation or provide a full account of safety.
The most defensible conclusion is therefore about what the trial set out to measure and how: a randomized, masked, placebo-controlled comparison using actigraphy across baseline and Week 24. The posted record does not provide enough numerical outcome information to judge the primary result. The distinction between a well-defined question and a reported answer is essential when reading trial records.
13. Why This Trial Matters Statistically
This trial is statistically notable for measuring activity outside the clinic using a wearable wrist device. The primary endpoint was intended to describe daily-life behavior in participants’ real environment, using data collected over 14 days at baseline and again at Week 24. This approach makes the measurement context part of the scientific question: the endpoint concerns activity as it occurs in everyday life, not only capacity or performance during a scheduled test.
The endpoint also depends on classification choices. Non-sedentary activity was defined using thresholds attributed to Freedson '98 and Koster '16, while moderate-to-vigorous physical activity was defined using Freedson '98. Different thresholds can describe different slices of movement, so naming the definitions is important for interpreting what the measured minutes represent. The registry record does not provide enough detail to assess device processing, wear-time rules, or sensitivity to alternative definitions.
The randomized and masked design provides a structured comparison, and the placebo arm used a regimen and titration scheme described as similar to the selexipag arm. These design features are relevant when interpreting measurements that may be affected by behavior, expectations, or treatment management. Their value for interpretation still depends on adequate reporting of results, follow-up, and analysis methods.
Finally, the registry record illustrates why an endpoint and a result are not interchangeable. It gives a detailed question and measurement schedule, but not the primary numerical estimates or their uncertainty. For statistical interpretation, the effect estimate, precision, analysis population, and missing-data handling are needed alongside the study design. Without those elements, the trial’s measurement strategy can be described, but the primary comparison cannot be quantified.
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 primary limitation for interpreting this trial from the registry record is that numerical results for the primary activity endpoint are not reported. The record describes more than one activity parameter and says that the primary outcome is not reduced to one comparison. Without estimates and uncertainty for the relevant parameters, it is not possible to assess the size, direction, or precision of the treatment comparison.
The registry does not report detailed analysis methods for the primary endpoint. In particular, it does not specify the model used to compare groups, adjustment variables, assumptions about outcome distributions, or how the repeated measurement periods were incorporated. The record defines the Full Analysis Set but does not give the number with usable actigraphy at baseline and Week 24 or explain how incomplete monitoring was handled.
Measurement details that can affect interpretation are also not reported in full. The endpoint description names the device-based activity definitions, but the record does not describe wear-time requirements, data-processing procedures, or how days with incomplete recordings were treated. It does not report whether the activity measures were examined for sensitivity to alternative thresholds.
The record lists secondary outcomes and counts of outcome measures and analyses, but does not identify a complete multiplicity strategy or provide the numerical secondary results. It also does not report the trial’s original sample-size justification, interim analyses, or a complete statistical analysis plan. These details are not reported in the registry record and should not be inferred from the sample-size planning assumptions.
Safety information is limited to event counts, deaths, and listed serious-event terms. The information does not establish event timing, exposure duration, causal attribution, or the context needed to compare event risks. These reporting limitations constrain interpretation; they do not demonstrate that an analysis or procedure was absent from the full trial documentation.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Effect of Selexipag on Daily Life Physical Activity of Patients With Pulmonary Arterial Hypertension. — NCT03078907.
- Registry record last updated 2025-03-30; status last verified 2025-03.
- Results first posted 2021-02-23.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
The record describes a completed, randomized, parallel-group, placebo-controlled phase 4 study of selexipag in pulmonary arterial hypertension, with enrollment of 108 participants. The official title describes a multicenter, double-blind study, while the registry lists quadruple masking. The study ran from 2017-11-08 to primary completion on 2020-02-10.
The primary objective was to assess daily-life physical activity using a wearable wrist device. The primary endpoint concerned change from baseline to Week 24 in minutes of non-sedentary activity and moderate-to-vigorous physical activity, measured over 14 days at each assessment period. The Full Analysis Set was defined as all participants randomly assigned to a study treatment.
The registry also lists symptom, functional class, walking distance, dyspnea, and biomarker outcomes. Serious adverse events were recorded for 3 of 53 participants in the selexipag group and 6 of 55 participants in the placebo group; deaths were 0 in both groups. Numerical primary efficacy estimates, detailed analysis methods, and missing-data procedures are not reported in the registry record.