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 A Study of the Effectiveness of Sitaxsentan Sodium in Patients With Diastolic Heart Failure (NCT00303498), a randomized phase 2 study. The primary outcome is Change From Baseline in Treadmill Exercise Time at Maintenance Phase Week 24.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00303498 |
| Phase | Phase 2 |
| Condition | Diastolic Heart Failure |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Triple |
| Enrollment | 200 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Pfizer |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned people with chronic heart failure and a left ventricular ejection fraction of at least 50%, described in the registry record as diastolic heart failure. The primary-outcome population was narrower than everyone randomized: it included participants who received at least one dose of study drug and had valid treadmill-test values at baseline and after baseline during the maintenance phase. The record gives an enrollment of 200, but does not report how many people met that primary-outcome population definition.
Intervention
The intervention was sitaxsentan sodium, an endothelin-A receptor blocker. The study aim was to assess whether long-term blockade, described as at least 6 months at the target dose, showed functional benefit. The record does not give arm-specific dosing details or confirm how long individual participants received treatment.
Comparator
The comparator was placebo. The trial used randomized allocation, a parallel-group model, and triple masking. The record does not describe the specific roles covered by masking, allocation procedures, or the details of how the placebo was administered.
Primary question
The primary endpoint was change from baseline in treadmill exercise time at maintenance phase week 24, measured in seconds. The clinical question was whether exercise time changed during the study in participants assigned to sitaxsentan sodium compared with those assigned to placebo. The registry record does not report a single result comparing the groups, so the direction and precision of any between-group difference cannot be described from this record.
3. Trial Design
This was a phase 2, randomized, triple-masked, parallel-group, placebo-controlled study. The registry record lists an enrollment of 200 and marks the study as completed. It identifies Pfizer as the sponsor and lists diastolic heart failure as the condition. The start date is 2006-03-27, and the primary completion date is 2008-05-01. These dates describe the study record; they do not establish how long each participant was followed.
The stated aim was to evaluate long-term endothelin-A receptor blockade with sitaxsentan sodium in people with chronic heart failure and a left ventricular ejection fraction of at least 50%. The intervention and placebo were assigned in a randomized parallel-group design. Triple masking indicates that the record characterizes the study as masked at three levels, but it does not say which people or roles were masked. The method used to generate the allocation sequence, conceal assignments, or preserve masking is not reported in the registry record.
The primary outcome was change from baseline in treadmill exercise time at maintenance phase week 24. Other listed outcomes addressed cardiac measurements, quality of life, and New York Heart Association functional class at maintenance phase week 24. The record lists seven secondary outcome measures and eight analyses, but does not provide enough detail to reconstruct how those analyses relate to each outcome or how they were prioritized.
The study is labeled exploratory and phase 2. Those labels describe its stated stage and purpose, but do not supply evidence about the size or certainty of an effect. The record does not report a detailed statistical analysis plan, the planned sample-size justification, interim analyses, or arm-specific treatment duration. It also does not provide a single primary-outcome comparison. Consequently, the design can be described, but the primary comparison cannot be independently interpreted from a reported estimate and its uncertainty.
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.
Before assignment: Study consisted of a 10-week dose adjusting Run-In Phase followed by a 24-week Maintenance Phase.
Run-In-Phase (10 Weeks)
| Stage | Sitaxsentan | Placebo |
|---|---|---|
| STARTED | 128 | 64 |
| Treated | 127 | 64 |
| COMPLETED | 104 | 56 |
| NOT COMPLETED | 24 | 8 |
Reasons for not completing this period:
| Reason | Sitaxsentan | Placebo |
|---|---|---|
| Adverse Event | 5 | 1 |
| Physician Decision | 0 | 1 |
| Withdrawal by Subject | 5 | 0 |
| Sponsor Decision | 6 | 3 |
| Other | 4 | 1 |
| Treatment Interrupted More Than 7 Days | 3 | 2 |
| Unable to Tolerate 25 mg Dose | 1 | 0 |
Maintenance Phase (24 Weeks)
| Stage | Sitaxsentan | Placebo |
|---|---|---|
| STARTED | 104 | 56 |
| COMPLETED | 90 | 48 |
| NOT COMPLETED | 14 | 8 |
Reasons for not completing this period:
| Reason | Sitaxsentan | Placebo |
|---|---|---|
| Elevation in Liver Enzyme Values | 1 | 0 |
| Death | 1 | 0 |
| Adverse Event | 2 | 1 |
| Physician Decision | 1 | 0 |
| Withdrawal by Subject | 3 | 4 |
| Sponsor Decision | 4 | 0 |
| Other | 1 | 0 |
| Treatment Interrupted More Than 7 Days | 1 | 2 |
| Required Chronic Heart Failure Treatment | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: Intent-to-treat (ITT) population was defined as all participants who received at least 1 dose of study drug and had at least 1 valid treadmill test value at baseline and post-baseline during maintenance phase. Last observation carried forward (LOCF) method was used to impute missing values.
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.
Population: Safety population was defined as all the participants who took at least 1 dose of study drug during the study.
| Characteristic | Unit | Sitaxsentan | Placebo | Total |
|---|---|---|---|---|
| Participants analysed | 127 | 64 | 191 | |
| Age, Continuous | Years | 65.0 (SD 10.94) | 64.7 (SD 9.99) | 64.9 (SD 10.61) |
| Sex: Female, Male: Female | Participants | 76 | 45 | 121 |
| Sex: Female, Male: Male | Participants | 51 | 19 | 70 |
6. Primary Endpoint
The registry lists the primary outcome as Change From Baseline in Treadmill Exercise Time at Maintenance Phase Week 24, measured over Baseline, Week 24 (Maintenance Phase).
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Full Range |
| Unit | Seconds |
| Endpoint classification | not reduced to a single comparison |
Treadmill exercise time measures how long a participant continues during a standardized exercise test. The registry describes a two-minute incremental Naughton protocol: it begins with a warm-up, then proceeds at a specified treadmill speed while the incline increases at regular intervals. The total exercise time is recorded in seconds. The endpoint is the change in that time from baseline to maintenance phase week 24.
Exercise time is used as a measure of functional capacity in people with cardiac disease. In general, a longer or shorter test duration can reflect a change in the ability to sustain the test, but the endpoint alone does not identify the cause of a change. Performance may reflect multiple aspects of health and testing circumstances; interpretation therefore depends on the comparison between randomized groups, the measurement process, and the uncertainty around the estimated difference.
The registry specifies the median and full range as the summary format for this outcome. A median describes the midpoint of the observed values, while a full range describes the lowest and highest values. These summaries can convey the spread and central location of individual changes, but they do not by themselves provide a treatment-effect estimate or show how precisely the groups differ. The record does not report the group-level primary-outcome values or a single comparison, so the endpoint’s measured result cannot be stated.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the question and endpoint but does not report a single primary-outcome comparison. It therefore does not support a statement about the estimated difference between sitaxsentan sodium and placebo in change in treadmill exercise time. No group-specific median changes, between-group estimate, confidence interval, or p-value for that comparison are reported in the registry record. Without these quantities, neither the direction of a comparative result nor its precision can be assessed from the record.
The endpoint is change from baseline at maintenance phase week 24, not simply the exercise time measured at one visit. A within-group change and a between-group contrast answer different questions. A change within an arm describes how that arm’s participants changed over time; a randomized treatment comparison asks whether changes differed between assigned groups. The registry does not provide the single between-group result needed to distinguish those interpretations.
The listed summary is the median with the full range. This format describes the distribution of individual changes in each group, if group summaries are reported. A comparison of medians is not automatically the same as a comparison of means, and the full range does not show the precision of a treatment-effect estimate. General statistical interpretation would usually consider an estimate together with an uncertainty interval and the analysis method. Those elements are not reported as a single primary-outcome comparison in the registry record.
The missing comparative result is not evidence that the groups were the same, nor is it evidence that they differed. Absence of a reported estimate leaves the magnitude and uncertainty unresolved. It also prevents assessment of whether any observed change might be clinically important. The record’s exploratory label does not replace a reported result or define a threshold for meaningful change.
The registry lists secondary outcomes involving transmitral inflow and mitral annular velocity, left ventricular mass, Minnesota Living With Heart Failure questionnaire scores, and change in New York Heart Association functional class. These address different aspects of cardiac function, reported health status, and functional classification. Their presence does not supply the missing primary comparison, and the record does not give a single integrated interpretation across these measures.
Safety counts are available separately from the efficacy endpoint. They describe participants with reported serious or other adverse events in the listed groups, but the record does not establish that these counts are directly comparable without further information on exposure, event definitions, and follow-up. The counts should not be used to infer the treadmill outcome or to characterize the overall benefit-risk balance.
In short, the record supports a description of the randomized study design, its planned functional endpoint, its stated analysis population, and certain safety counts. It does not support a quantitative conclusion about the primary treatment comparison. The key statistical distinction is between knowing what outcome was measured and knowing what the comparative estimate showed; the record provides the former but not the latter.
9. Statistical Methods Explained
The statistical details in a registry record can clarify how an endpoint was defined and which participants contributed data, but they do not substitute for an analysis plan or a reported comparison. In this study, the primary endpoint is described as a change from baseline, the summary parameter is the median, and the dispersion is the full range. The record also describes a particular population definition and a method for handling missing values. Several other features needed to reproduce or fully assess the analysis are not reported in the registry record.
What does a change-from-baseline endpoint represent?
A change score expresses how an individual’s measurement at follow-up differs from that individual’s baseline measurement. The study’s endpoint concerns treadmill exercise time at baseline and maintenance phase week 24. In general, analyzing change can account for the starting measurement when describing subsequent movement, but the treatment question remains comparative: the relevant contrast is between changes in the randomized groups. A change observed within one group alone does not establish that the groups changed differently.
The registry specifies median and full range. The median is a rank-based description of the center of a distribution: it divides ordered observations into lower and upper portions. It is less influenced by extreme values than a mean, although it does not use the distance of every observation from the center in the same way. The full range reports the extremes and can be strongly affected by unusually low or high observations. Neither summary alone gives a confidence interval for the between-group effect.
What does the analysis population include?
The primary-outcome population is described as intent-to-treat, but its operational definition is specific: participants had to receive at least one dose of study drug and have at least one valid treadmill value at baseline and after baseline during the maintenance phase. In general, an intention-to-treat approach aims to preserve the benefits of randomized assignment by analyzing participants according to their assigned group. The registry’s stated definition also requires treatment exposure and valid outcome measurements, so it should be read as written rather than assumed to include every randomized participant.
The record does not provide the number of participants in this population or the numbers excluded for not meeting its criteria. It also does not report how participants with no valid post-baseline test were handled beyond the stated imputation approach for missing values. The number enrolled is not interchangeable with the number contributing to a particular endpoint analysis.
How should last observation carried forward be understood?
The registry says last observation carried forward was used to impute missing values. In general, this method replaces a missing later measurement with the participant’s most recently observed value. It is a simple way to form a complete analysis dataset, but it assumes that the carried-forward value is an adequate stand-in for the unobserved outcome. If outcomes would have continued to change after the last measurement, that assumption may not hold. The direction and extent of any resulting bias depend on why data are missing and how outcomes evolve; those features are not reported in the registry record.
Imputation does not recover an unobserved measurement as a known fact. It creates an analysis value under an assumption. A careful interpretation therefore considers the amount and pattern of missingness, the timing of the last observed test, and whether alternative assumptions produce similar conclusions. The record does not report those details or sensitivity analyses for the primary endpoint.
What is needed to interpret a treatment comparison?
A comparative estimate describes the difference between randomized groups on the selected outcome. A confidence interval, in general, gives a range of values compatible with the data and the assumptions of the analysis; it communicates uncertainty rather than guaranteeing that the true effect lies within the interval. A p-value, in general, measures how compatible the data are with a specified null model, under the assumptions of the statistical test. Neither is reported as part of a single primary-outcome comparison in the registry record. The test, model, adjustment variables, and method for calculating uncertainty are also not reported.
Variation in individual outcomes can matter when measurements are more dispersed than a chosen model expects. In general, over-dispersion means the observed variation is greater than the model allows, which can make conventional uncertainty estimates too small if it is ignored. This is a statistical concept, not a reported finding about this study. The registry does not provide enough outcome-level information to assess whether over-dispersion occurred or whether it was considered.
What does the planning illustration describe?
The stated planning framework uses a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. It describes illustrations based on specified fractions of an observed effect. Such values, when presented, are planning quantities: they estimate the number of participants per arm that a design might require under the stated assumptions. They are not observed power and do not show the probability that the completed trial found an effect. The registry record does not provide the planned sample-size justification, and the primary comparative effect needed to interpret these illustrations is not reported as a single result.
The assumptions are consequential. A planning calculation based on a different target effect, allocation, variability, or statistical model could give a different requirement. A normal approximation is a modeling choice, not a guarantee that the outcome follows a normal distribution. These general points explain how planning illustrations should be read, but they do not establish which design assumptions were used by the investigators beyond those explicitly stated in the registry record.
What can be concluded about the analysis plan?
The record does not report the full statistical analysis plan, any interim analyses, the prespecified primary comparison procedure, or methods for controlling multiplicity. It lists secondary outcomes and analyses, but does not specify how the family of tests was handled. This matters because evaluating multiple outcomes or comparisons can increase the chance of finding a seemingly unusual result by chance if the analysis does not account for that multiplicity. No conclusion about the actual procedure can be drawn from the number of listed measures alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary treadmill exercise-time outcome and several secondary measures, including cardiac measurements, quality-of-life scores, and change in functional class. The number of listed outcomes does not reveal how many statistical tests were planned or performed. The record does not report whether the investigators adjusted for multiple comparisons, used a hierarchy of outcomes, or treated secondary analyses as exploratory. Without that information, the chance of false-positive findings across a set of tests cannot be evaluated from the registry record.
The primary-outcome analysis population requires at least one dose and valid baseline and post-baseline treadmill values during the maintenance phase. This definition is important because it identifies who could contribute to the endpoint analysis, but the record does not give the population count or describe exclusions in detail. The enrollment figure should not be treated as the number analyzed for the endpoint.
Missing outcome values were imputed using last observation carried forward. In general, this approach carries a participant’s most recent observed value forward to a later missing time point. Its validity depends on assumptions about what would have happened after the last measurement. The registry does not report how much data were missing, why measurements were missing, the timing of missingness, or whether sensitivity analyses tested alternative assumptions. Consequently, the robustness of the primary analysis to missing-data assumptions cannot be assessed.
The full statistical analysis plan, interim-analysis details, and a single primary-outcome comparison are not reported in the registry record. These omissions limit assessment of prespecification, multiplicity, and the sensitivity of the result to analysis choices.
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 |
|---|---|---|---|
| Sitaxsentan | 25 | 127 | 19.7% |
| Placebo | 16 | 64 | 25.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Sitaxsentan | 107 of 127 |
| Placebo | 54 of 64 |
Most frequent serious adverse event terms
| Event term | Organ system | Sitaxsentan | Placebo |
|---|---|---|---|
| Chest pain | General disorders | 3 of 127 | 2 of 64 |
| Cardiac failure congestive | Cardiac disorders | 2 of 127 | 2 of 64 |
| Pneumonia | Infections and infestations | 3 of 127 | 1 of 64 |
| Coronary artery disease | Cardiac disorders | 3 of 127 | 0 of 64 |
| Asthma | Respiratory, thoracic and mediastinal disorders | 3 of 127 | 0 of 64 |
| Dyspnoea | Respiratory, thoracic and mediastinal disorders | 1 of 127 | 2 of 64 |
| Anaemia | Blood and lymphatic system disorders | 1 of 127 | 1 of 64 |
| Cardiac failure | Cardiac disorders | 1 of 127 | 1 of 64 |
| Non-cardiac chest pain | General disorders | 0 of 127 | 2 of 64 |
| Sepsis | Infections and infestations | 2 of 127 | 0 of 64 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Sitaxsentan | Placebo |
|---|---|---|---|
| Oedema peripheral | General disorders | 20 of 127 | 8 of 64 |
| Dyspnoea | Respiratory, thoracic and mediastinal disorders | 18 of 127 | 8 of 64 |
| Headache | Nervous system disorders | 9 of 127 | 11 of 64 |
| Urinary tract infection | Infections and infestations | 12 of 127 | 5 of 64 |
| Upper respiratory tract infection | Infections and infestations | 13 of 127 | 3 of 64 |
| Dizziness | Nervous system disorders | 10 of 127 | 6 of 64 |
| Palpitations | Cardiac disorders | 6 of 127 | 8 of 64 |
| Nausea | Gastrointestinal disorders | 10 of 127 | 4 of 64 |
| Fatigue | General disorders | 10 of 127 | 4 of 64 |
| Pain in extremity | Musculoskeletal and connective tissue disorders | 9 of 127 | 4 of 64 |
Serious events with the highest arm-level rate: cardiac failure congestive (3.1%), chest pain (3.1%), non-cardiac chest pain (3.1%), dyspnoea (3.1%), coronary artery disease (2.4%).
The registry lists serious adverse events for the sitaxsentan group as 25 participants affected among 127 at risk, and for the placebo group as 16 among 64 at risk. It also lists other adverse events affecting 107 participants in the sitaxsentan group and 54 in the placebo group, with 127 and 64 participants at risk, respectively. These are counts, not a complete account of event severity, duration, or clinical context.
The listed serious-event terms include cardiac failure congestive, chest pain, non-cardiac chest pain, and dyspnoea, each reported as 3.1%; coronary artery disease and pneumonia are each reported as 2.4%. The registry does not identify these terms by treatment group in the available record, so they should not be assigned to either arm. The record does not report deaths.
General statistical interpretation of safety counts requires attention to definitions, follow-up, and exposure. Participants may experience more than one event, and a count of participants affected is not the same as a count of all event episodes. The registry record does not provide enough detail to determine whether the listed counts reflect repeated events, how events were adjudicated, or whether time at risk differed between groups. These figures alone do not establish a causal difference in safety between treatments.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized, triple-masked, placebo-controlled phase 2 study evaluated sitaxsentan sodium in people described as having diastolic heart failure. Its primary endpoint was change from baseline in treadmill exercise time at maintenance phase week 24. It also specifies the primary-outcome population and says missing values were handled using last observation carried forward. These details explain what the study set out to measure and some aspects of how its data were handled.
The registry record does not report a single comparative result for the primary endpoint. It therefore does not establish whether the sitaxsentan group had a larger, smaller, or similar change in exercise time compared with placebo. It also does not report a confidence interval or p-value for a primary comparison, so the precision and statistical compatibility of any comparative effect cannot be assessed. No treatment-effect magnitude should be inferred from the study’s design, endpoint description, or safety counts.
The presence of secondary outcomes does not fill that gap. Changes in cardiac measurements, questionnaire scores, or functional class address distinct questions and would require their own reported estimates and uncertainty. The registry record does not describe how multiplicity was handled, so a collection of outcome findings, even if available elsewhere, would need to be interpreted in light of the analysis plan and prespecification.
Likewise, the recorded safety counts are descriptive. They do not, on their own, show whether event risks differed between groups, and the record does not report deaths. A safety interpretation would need context about event definitions, follow-up, treatment exposure, and the handling of participants with multiple events.
The appropriate statistical conclusion is limited: the record describes a trial design and intended functional outcome, but does not give the primary comparative estimate needed to judge the observed effect or its uncertainty. That is a limitation of what is reported in the registry record, not evidence that the treatment was beneficial, ineffective, or equivalent to placebo.
13. Why This Trial Matters Statistically
This trial raises several recurring issues in the interpretation of clinical research. First, an endpoint description is not a result. Knowing that treadmill exercise time was measured at baseline and maintenance phase week 24 identifies the outcome of interest, but a treatment comparison requires group results and an estimate of how different the groups were. Without that comparison, the central statistical question remains unanswered in the registry record.
Second, the population used for analysis matters. The registry calls the primary population intent-to-treat but defines it through treatment exposure and availability of valid treadmill measurements at baseline and after baseline. Readers need the operational definition, not only the label, because the analyzed population determines which randomized participants contribute information. The record does not state how many met the definition.
Third, missing-data handling is part of the analysis, not a minor reporting detail. Last observation carried forward imposes an assumption about missing later outcomes. Understanding the degree to which conclusions depend on that assumption requires information about missingness and sensitivity analyses, which are not reported in the registry record.
Fourth, exploratory phase 2 studies often include several outcomes that speak to different domains. Statistical interpretation requires knowing which comparisons were prespecified and how multiplicity was addressed. The registry lists several measures, but does not explain a testing hierarchy or adjustment strategy. The outcome list alone cannot show whether a particular finding was confirmatory or exploratory.
Finally, sample-size planning and observed evidence are distinct. A planning illustration based on a target effect and modeling assumptions is not a result from the randomized comparison, and it is not observed power. Keeping those concepts separate is essential when evaluating what a study can support. Here, the reported design information is more complete than the reported primary-outcome result, making transparent separation of methods and evidence especially important.
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 statistical interpretation is that the registry record does not provide a single comparative result for the primary treadmill endpoint. Group-level changes, a between-group estimate, and its uncertainty are not reported as one comparison. This prevents evaluation of the direction, magnitude, and precision of the primary finding.
The primary-outcome analysis population is defined by receipt of at least one dose and availability of valid treadmill measurements at baseline and after baseline in the maintenance phase. The record does not report the number of participants meeting those conditions, the number with missing tests, or the reasons measurements were unavailable. Enrollment therefore cannot be used to infer the endpoint’s analyzed sample size.
Last observation carried forward is the stated method for missing values, but the registry does not give the extent or pattern of missingness or report sensitivity analyses. The impact of this assumption on the endpoint result cannot be assessed. The full statistical analysis plan, interim analyses, sample-size justification, and multiplicity procedure are also not reported in the registry record.
The outcome summary is described as median with full range. Without the underlying group summaries and a comparative estimate, this format cannot establish a treatment difference or its precision. The record also does not describe the procedures for treadmill-test quality control, outcome assessment, or allocation concealment.
For safety, the record lists affected participants and terms but gives limited context about event definitions, repeated events, exposure duration, and follow-up. The listed serious-event terms are not assigned to treatment groups in the available record, and deaths are not reported. These limitations restrict comparisons and should not be resolved by assumptions.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Study of the Effectiveness of Sitaxsentan Sodium in Patients With Diastolic Heart Failure — NCT00303498.
- Registry record last updated 2023-01-04; status last verified 2022-12.
- Results first posted 2023-01-04.
- 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 registry record describes a completed phase 2, randomized, triple-masked, parallel-group study of sitaxsentan sodium versus placebo in diastolic heart failure. It records an enrollment of 200 and identifies treadmill exercise-time change at maintenance phase week 24 as the primary outcome. The primary-outcome population required at least one dose and valid baseline and post-baseline treadmill measurements during the maintenance phase; last observation carried forward was used for missing values.
The record lists secondary outcomes addressing cardiac measures, quality of life, and functional class. It also reports serious and other adverse-event counts. However, it does not report a single comparative primary-outcome result, including a group contrast with its uncertainty. The registry record therefore permits a description of the design and analysis features but does not support a quantitative conclusion about the primary treatment comparison.