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 Using Mirabegron to Increase BP in Patients With POTS (NCT06133075), a randomized phase 2 study. The primary outcome is Blood Pressure.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT06133075 |
| Phase | Phase 2 |
| Condition | Postural Orthostatic Tachycardia Syndrome, Chronic Orthostatic Intolerance, Syncope |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 20 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Cedars-Sinai Medical Center |
| Results posted | Yes |
2. Clinical Question
Population
People with postural orthostatic tachycardia syndrome (POTS) and a documented history of hypotension that was inadequately responsive to conventional treatments. The registry record also lists chronic orthostatic intolerance and syncope among the conditions.
Intervention
Mirabegron 50 mg for 8 weeks in one group, or mirabegron 25 mg for 8 weeks in the other group.
Comparator
The registry describes two randomized dose groups. It does not describe a placebo or untreated comparator; the comparison is between the two mirabegron doses.
Primary question
How does average systolic blood pressure, measured by 24-hour ambulatory monitoring, change from baseline to 8 weeks in each dose group? Average diastolic blood pressure is also reported, but is not identified as the primary measure.
The study is described as a pilot dose-finding study. Its stated hypothesis is that mirabegron increases systolic blood pressure and may affect syncope or presyncope, quality of life, functional capacity, chest pain, and overactive bladder symptoms in the selected POTS population. Those aims describe questions the study set out to examine; they are not evidence that any outcome changed.
The registry record lists secondary outcomes involving syncope, hypotensive episodes, activity status, quality of life, angina-related symptoms, and overactive bladder symptoms. Numerical results for these outcomes are not reported in the registry record. The primary blood pressure results are also not reported in a form that allows the change or the difference between dose groups to be assessed.
3. Trial Design
This is a phase 2, randomized, open-label, parallel-group study with a registered enrollment of 20. The record describes 10 participants assigned to the 50 mg group and 10 to the 25 mg group, each receiving the assigned dose for 8 weeks. “Open-label” means masking was not used; the record lists masking as none. The design is parallel rather than crossover, so the two dose groups are distinct arms rather than participants switching between doses.
The study is characterized as a pilot dose-finding trial. Its target population is people with POTS who have a documented history of hypotension inadequately responsive to conventional treatments. The listed conditions also include chronic orthostatic intolerance and syncope. The registry names Cedars-Sinai Medical Center as the sponsor and the American Heart Association as a funder in the study summary.
The registry record lists a start date of 2023-12-22, a primary completion date of 2025-05-20, and a completed status. The primary endpoint timeframe is 8 weeks. A 24-hour ambulatory blood pressure monitor was used to measure systolic and diastolic blood pressure.
Although the intended group sizes are 10 per dose, the primary blood pressure comparison includes only participants with monitor data available at both baseline and 8 weeks: 7 in the 50 mg group and 8 in the 25 mg group. The record attributes this reduced availability to technical reasons. Randomization, allocation, and the planned treatment duration are design features; they do not by themselves establish what the blood pressure results were. Numerical results and a detailed statistical analysis plan 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 | 50 mg Group | 25 mg Group |
|---|---|---|
| STARTED | 10 | 10 |
| COMPLETED | 8 | 8 |
| NOT COMPLETED | 2 | 2 |
Reasons for not completing this period:
| Reason | 50 mg Group | 25 mg Group |
|---|---|---|
| Adverse Event | 1 | 2 |
| Lost to Follow-up | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: Out of 10 participants, only 7 participants in the 50 mg group and 8 participants in the 25 mg group had ABPM available for comparison at both baseline and at 8 weeks. Therefore, we only included them in the analysis to determine if there are significant changes of blood pressure from baseline to 8 weeks. Patients with incomplete data were not analyzed because we cannot compare baseline with 8 weeks.
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 | 50 mg Group | 25 mg Group | Total |
|---|---|---|---|---|
| Participants analysed | 10 | 10 | 20 | |
| Age, Continuous | years | 36 (SD 10) | 39 (SD 13) | 38 (SD 11) |
| Sex: Female, Male: Female | Participants | 10 | 9 | 19 |
| Sex: Female, Male: Male | Participants | 0 | 1 | 1 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 2 | 1 | 3 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 6 | 9 | 15 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 2 | 0 | 2 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| 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 | 6 | 9 | 15 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 2 | 1 | 3 |
| Medications: Ivabradine | participants | 4 | 6 | 10 |
| Medications: Cromolyn Sodium | participants | 2 | 2 | 4 |
| Medications: Diphenhydramine | participants | 1 | 1 | 2 |
| Medications: Famotidine | participants | 3 | 2 | 5 |
| Medications: Midodrine | participants | 1 | 1 | 2 |
| Medications: Verapamil | participants | 0 | 1 | 1 |
| Medications: Atenolol | participants | 1 | 0 | 1 |
| Medications: Bisoprolol | participants | 1 | 0 | 1 |
| Medications: Citalopram | participants | 1 | 0 | 1 |
| Medications: Fludrocortisone | participants | 3 | 0 | 3 |
| Diagnoses: Alcohol Sensitive | participants | 1 | 3 | 4 |
| Diagnoses: Chest Pain | participants | 4 | 4 | 8 |
| Diagnoses: Dizziness | participants | 5 | 2 | 7 |
| Diagnoses: Hypermobile Ehlers-Danlos Syndrome (hEDs) | participants | 4 | 6 | 10 |
| Diagnoses: Mast Cell Activation Syndrome (MCAS) | participants | 2 | 6 | 8 |
| Diagnoses: Palpitations | participants | 6 | 7 | 13 |
| Diagnoses: Post-Prandial Hypotension | participants | 0 | 1 | 1 |
| Diagnoses: Pre-Syncope | participants | 9 | 9 | 18 |
| Diagnoses: Skin Sensitivity | participants | 6 | 4 | 10 |
| Diagnoses: Syncope | participants | 3 | 8 | 11 |
| Average Sinus Rate | beats per minute | 69 (SD 8) | 68 (SD 10) | 69 (SD 9) |
6. Primary Endpoint
The registry lists the primary outcome as Blood Pressure, measured over 8 weeks.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | mmHg |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is average systolic blood pressure (SBP), measured in mmHg using a 24-hour ambulatory blood pressure monitor (ABPM). The registry describes comparison of measurements at baseline and 8 weeks. It also reports average diastolic blood pressure (DBP), but identifies average SBP as the primary outcome.
Ambulatory monitoring records blood pressure over a full day rather than relying on a single measurement. In general, repeated measurements across ordinary activity and rest can characterize blood pressure over the monitoring period. The endpoint is therefore a mean of a continuous measure, with standard deviation specified as the measure of dispersion. This provides a summary of the group’s average level and the spread of individual measurements, although neither summary alone describes every participant’s trajectory.
For this study, the intended clinical question concerns whether blood pressure changes during the 8-week treatment period in the selected population. The registry says the primary comparison includes participants with ABPM available at both baseline and 8 weeks. Because numerical means, standard deviations, changes, and uncertainty estimates are not reported in the registry record, the magnitude and precision of any change cannot be evaluated from the posted results.
SBP is the primary measure because the study summary specifically states the hypothesis that mirabegron increases systolic blood pressure. DBP is a related reported measure, but it should not be substituted for the prespecified primary outcome when interpreting the study question.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the primary outcome and the measurement approach, but numerical primary outcome results are not reported in the registry record. There are no posted SBP or DBP means, standard deviations, changes from baseline, confidence intervals, or test results available in the record. As a result, the direction, size, and precision of blood pressure change cannot be assessed. The same applies to the listed secondary outcomes: their names are recorded, but numerical findings are not reported.
The planned comparison is between two active doses, not between mirabegron and placebo or no treatment. Even if numerical changes within each group were available, a change from baseline in one group would not by itself establish a difference between doses. A direct dose comparison would require an estimate of the between-group contrast and its uncertainty. Such results are not reported in the registry record.
The primary blood pressure analysis is based on 7 participants in the 50 mg group and 8 in the 25 mg group, rather than all 20 enrolled participants. The record explains that ABPM was unavailable for some participants for technical reasons and specifies that only participants with measurements at both baseline and 8 weeks were included. This complete-measurement subset is the relevant analysis population for the described endpoint. Its results may not fully represent all enrolled participants if those with unavailable measurements differed in meaningful ways, but the record does not describe whether that occurred.
In general, an estimate of a mean change describes the observed average, while a confidence interval communicates uncertainty around that estimate under the assumptions of the analysis. Without estimates and intervals, readers cannot distinguish a small, imprecise change from a larger, more precisely estimated one. No conclusion about statistical significance or the comparative effect of the doses can be drawn from the registry information.
The study is a small pilot, with 20 participants registered and fewer with paired ABPM data. This context matters when considering how much information a study can provide, but no result should be inferred from sample size alone. The registry does not report a sample-size justification, analysis plan, or power target for the trial itself. Any planning illustration based on an observed effect is not observed power and cannot replace reported outcome estimates.
The completed status indicates that the study is recorded as completed; it does not mean that numerical findings are available in the registry record. The record’s descriptions establish what was intended and how blood pressure was measured, not what effect was observed.
9. Statistical Methods Explained
The registry describes a continuous primary outcome: average SBP in mmHg, summarized as a mean with standard deviation. It describes repeated measurement at baseline and 8 weeks and says that the primary comparison includes participants with ABPM at both time points. The record does not report the numerical analysis results or a detailed statistical analysis plan. The explanations below distinguish the recorded design from general statistical principles.
What does a mean summarize?
In general, a mean combines the measured values in a group into an average. It is useful for describing the central level of a continuous measure such as blood pressure, but it does not show whether participants had similar values or widely differing values. A mean change from baseline would describe the average within-person change among the analyzed participants. A group mean at 8 weeks alone would not communicate the same information as a paired change, because it does not account directly for each participant’s baseline measurement.
The standard deviation describes how dispersed measurements are around the mean. It is not the same as the standard error or a confidence interval: the standard deviation describes variability among observations, whereas uncertainty in an estimated mean depends on both variability and the amount of information available. The registry names standard deviation as the dispersion measure, but the numerical standard deviations are not reported in the registry record.
Why does pairing matter?
In general, measurements from the same person at two times are paired. An analysis of change uses the within-person relationship between baseline and follow-up measurements. This can be informative because each person serves as their own reference for change, but it still requires complete and appropriately handled measurements. The registry states that only participants with ABPM available at both baseline and 8 weeks were included in the blood pressure comparison. It does not give the individual paired values or a numerical summary of the changes.
The record describes a separate group receiving each dose. The relevant dose comparison would concern differences between these randomized groups, not merely whether a change within one group differs from zero. In general, a within-group test and a between-group comparison address different questions. The registry does not report a numerical between-group estimate or the method used to test it.
What does uncertainty convey?
In general, a confidence interval gives a range of values compatible with the data and the statistical model at a stated confidence level. A narrow interval indicates greater precision than a wide interval, but interpretation also depends on the range of effects that would matter for the research question. A p-value, when reported, describes the compatibility of data with a specified null model; it does not measure the size or importance of an effect. Neither confidence intervals nor p-values are reported for the primary outcome in the registry record.
There is no basis in the registry information to characterize the findings as statistically significant or not statistically significant. The numerical results needed to make that assessment are not reported. Statistical significance, even when available, would not by itself describe the magnitude or precision of a difference.
How should the planning illustration be read?
The accompanying sample-size illustration is described as a planning calculation based on the observed effect, not as the trial’s original design justification. Its stated assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation; the effect to detect is expressed as a stated fraction of the observed effect. Such calculations are hypothetical planning exercises. They do not show the probability that this completed study detected an effect, and they are not observed power.
The numerical outcome estimates needed to evaluate an effect-based planning illustration are not reported in the registry record. The record also does not report the trial’s own sample-size justification or target power. No planning conclusion should therefore be attributed to the study protocol from the illustration alone.
What is not specified?
The registry record does not report the statistical test or model used for the primary comparison, how distributional assumptions were checked, whether adjustment variables were used, or how missing measurements were handled beyond restricting the stated comparison to participants with both measurements. It does not report an interim analysis plan or a prespecified multiplicity strategy. General methods such as paired analyses, regression adjustment, or multiplicity correction should not be assumed to have been used.
The study lists several outcomes and two blood pressure measures, while the primary endpoint is average SBP. In general, testing multiple outcomes can increase the chance of at least one apparently unusual result if no adjustment or hierarchy is specified. Whether and how that issue was handled in this trial is not reported in the registry record. The absence of a stated plan is not evidence that a particular method was or was not used outside the registry.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists average SBP as the primary outcome and average DBP as an additional reported blood pressure measure. It also lists secondary outcomes involving syncope, hypotensive episodes, activity status, quality of life, angina-related symptoms, and overactive bladder symptoms. Considering multiple outcomes can raise a multiplicity question: in general, the more statistical comparisons made, the greater the chance that at least one appears notable by chance. A prespecified hierarchy or adjustment can address that issue, but the registry record does not report a multiplicity strategy.
The record describes the primary blood pressure analysis as limited to participants with measurements at both baseline and 8 weeks. ABPM was available for 7 participants in the 50 mg group and 8 participants in the 25 mg group, with technical reasons given for missing monitor availability. Restricting analysis to participants with complete measurements can be reasonable for a paired comparison, but it does not show whether missingness is unrelated to the outcome. The registry does not report an imputation method, sensitivity analysis, or comparison of participants with and without paired monitor data.
The registered enrollment is 20, with 10 intended for each dose group. The primary endpoint analysis population is smaller because not all participants had paired ABPM. The record does not report details about other analysis populations, exclusions beyond unavailable paired monitoring, or whether all randomized participants were analyzed according to assigned group. Those analysis-population details are not reported in the registry record.
A detailed statistical analysis plan, interim analysis information, and the trial’s sample-size justification are also not reported in the registry record. These omissions limit assessment of whether outcome definitions, analysis choices, and handling of missing data were specified in advance.
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 |
|---|---|---|---|
| 50 mg Group | 0 | 10 | 0.0% |
| 25 mg Group | 0 | 10 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| 50 mg Group | 0 of 10 |
| 25 mg Group | 0 of 10 |
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 |
|---|---|
| 50 mg Group | 5 of 10 |
| 25 mg Group | 5 of 10 |
Most frequent non-serious adverse event terms
| Event term | Organ system | 50 mg Group | 25 mg Group |
|---|---|---|---|
| Diarrhea | Gastrointestinal disorders | 1 of 10 | 2 of 10 |
| Nausea | Gastrointestinal disorders | 1 of 10 | 1 of 10 |
| Urinary Discomfort | Renal and urinary disorders | 0 of 10 | 2 of 10 |
| Skin Irritation from Patch Electrode | Musculoskeletal and connective tissue disorders | 1 of 10 | 1 of 10 |
| Blurry Vision | Eye disorders | 1 of 10 | 0 of 10 |
| Palpitations | Nervous system disorders | 1 of 10 | 0 of 10 |
The registry reports serious adverse events for 0 of 10 participants at risk in the 50 mg group and 0 of 10 participants at risk in the 25 mg group. It reports other, non-serious adverse events for 5 of 10 participants at risk in each group. Deaths are reported as 0 in each group, and no serious adverse event terms are listed.
These figures count participants with reported events in the stated categories; they do not describe event severity beyond the serious versus other classification, the timing of events, or the number of events per participant. The record does not establish from these counts whether an event was judged related to treatment. The absence of a reported serious event in this record should not be read as proof that no serious event could occur, particularly in a study with 10 participants at risk in each group.
The figures are descriptive and do not support a precise comparison of safety between doses. The registry record does not provide further event details or statistical comparisons for adverse events.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized, open-label, parallel-group pilot study compared mirabegron 50 mg and 25 mg over 8 weeks in people with POTS and a documented history of hypotension inadequately responsive to conventional treatments. It specifies 24-hour ambulatory monitoring and identifies average SBP as the primary outcome. It also identifies DBP and several other outcomes of interest.
However, the registry record does not report numerical primary or secondary outcome results. It therefore does not show the average blood pressure values, the changes from baseline, the difference between doses, or the uncertainty around any estimate. The posted information cannot establish the direction or size of a blood pressure change or whether the two dose groups differed. No claim about treatment benefit or lack of benefit follows from the outcome data described in the record.
The primary blood pressure comparison uses participants with ABPM available at baseline and 8 weeks: 7 in the 50 mg group and 8 in the 25 mg group. This is fewer than the registered enrollment of 20. The record attributes the missing monitoring data to technical reasons, but it does not report whether participants with and without paired measurements differed or how missingness affected the results.
The adverse-event figures describe 0 serious events in each group and 5 participants with other adverse events in each group. They do not establish that any event was caused by the study drug, and the record gives no additional event-level detail. With the reported group sizes, these counts should be treated as descriptive rather than as a definitive comparison between doses.
In general, a pilot study can inform later research questions and design, but its purpose and sample size do not substitute for complete results. Here, outcome estimates and analysis details are not reported in the registry record, so interpretation must remain limited to the study design, measurement plan, available analysis counts, and recorded adverse-event figures.
13. Why This Trial Matters Statistically
This study illustrates an important distinction between a trial’s registered question and the evidence available to answer it. The registry identifies a clinically targeted population, two randomized doses, a continuous primary blood pressure measure, and an 8-week timeframe. Those details allow readers to understand what the study was intended to investigate, while the lack of numerical outcome results prevents assessment of the observed effect.
The record also makes the analysis population visible. Although enrollment was 20, the primary blood pressure comparison includes only participants with paired ABPM at baseline and 8 weeks: 7 in the 50 mg group and 8 in the 25 mg group. This is statistically important because conclusions about a mean change depend on the measurements that contribute to it, and missing data may affect both precision and representativeness. The reason recorded for unavailable monitoring is technical, but the registry does not provide enough information to assess the consequences.
Another useful lesson is that comparisons within groups and comparisons between groups answer different questions. The research question involves two active doses. A within-group change alone would not tell readers whether one dose performed differently from the other. A clear between-group estimate with an uncertainty interval would be needed for that comparative interpretation; such estimates are not reported in the registry record.
Finally, the study’s pilot and dose-finding characterization should not be confused with evidence of an effect. Planning assumptions and adverse-event counts are not substitutes for primary outcome estimates. The record shows why transparent reporting of numerical results, analysis methods, and missing-data handling is essential for judging what a clinical study can support.
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 central limitation for statistical interpretation is that numerical primary outcome results are not reported in the registry record. There are no reported SBP or DBP means, standard deviations, changes, between-group estimates, confidence intervals, or test results. Numerical findings for the listed secondary outcomes are also not reported. Consequently, the size and precision of any outcome effect cannot be assessed.
The primary blood pressure analysis is based on 7 participants in the 50 mg group and 8 participants in the 25 mg group, because only those participants had ABPM available at both baseline and 8 weeks. The registry attributes unavailable measurements to technical reasons but does not describe the missing-data pattern in more detail. It does not report sensitivity analyses or information that would show whether the analysis subset differed from the full enrolled group.
The registry record does not report the statistical method used for the primary comparison, the analysis populations for secondary outcomes, a multiplicity strategy, an interim analysis plan, or the trial’s sample-size justification. These omissions make it difficult to assess how the analysis was conducted or how outcome selection and missing data were handled. No specific method should be inferred from the design description alone.
The study is a pilot with 20 registered participants and two dose groups. That scale limits the amount of information available for detailed comparisons, but no precision estimate can be made without numerical results. The open-label design is recorded, while the registry does not provide further information about outcome-assessment procedures beyond use of ABPM. These limitations apply to interpretation of the record and do not establish what analyses or findings may exist outside it.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Using Mirabegron to Increase BP in Patients With POTS — NCT06133075.
- Registry record last updated 2026-04-08; status last verified 2026-03.
- Results first posted 2026-04-08.
- 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
This completed phase 2 study randomized 20 participants with POTS and a documented history of hypotension inadequately responsive to conventional treatments to mirabegron 50 mg or 25 mg for 8 weeks. It was open-label and used a parallel-group design. The primary outcome was average SBP measured with 24-hour ABPM; average DBP was also reported. The record lists secondary outcomes related to syncope, hypotensive episodes, activity status, quality of life, angina-related symptoms, and overactive bladder symptoms.
Paired ABPM was available for 7 participants in the 50 mg group and 8 in the 25 mg group. The registry record does not report numerical primary or secondary outcome results or a detailed analysis plan. Serious adverse events and deaths were recorded as 0 in each group; other adverse events were recorded for 5 participants in each group. These safety counts are descriptive and do not establish causation or comparative risk.