Ertugliflozin: Cardioprotective Effects on Epicardial Fat: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Ertugliflozin: Cardioprotective Effects on Epicardial Fat (NCT04167761), a na early/phase 1 study. The primary outcome is Rate of Isoproterenol-Stimulated Lipolysis in Adipose Tissue Depots to Measure Metabolic Flexibility.

2. Clinical Question

The research question concerns properties of adipose tissue, including metabolic flexibility, insulin sensitivity, cell size, and inflammation. The primary endpoint focuses specifically on lipolysis, a process assessed under basal, isoproterenol-stimulated, and insulin-suppressed conditions. These conditions allow the investigators to examine tissue responses in the assay rather than simply recording a single undifferentiated lipolysis value.

The tissue was collected during surgery, and the primary endpoint timeframe is described as the time to collect tissue during surgery, up to 15 minutes. The registry says that tissue was cultured with ertugliflozin and compared with a mock condition. This is a laboratory comparison involving tissue samples; it should not be read as a randomized comparison between people receiving and not receiving a medication. The registry does not report the exact sample count used in each tissue-depot or assay analysis.

3. Trial Design

The registry identifies this as an EARLY PHASE1 study with a single-group model and no masking. Allocation is listed as not applicable. The study is marked completed, with enrollment of 61. The recorded start date is 2020-07-01 and the primary completion date is 2023-12-31. Stanford University is listed as the sponsor.

The intervention is ertugliflozin, a drug that was applied to adipose tissue samples in vitro at a concentration of 25 µM. The record describes collecting adipose tissue from participants and incubating samples with ertugliflozin. Tissue depots named in the primary outcome description are epicardial, pericardial, and subcutaneous. A mock condition is also mentioned as the comparison for cultured cardiac adipose tissue explants.

Although the study has an intervention and a comparison condition at the tissue level, the registry’s design fields describe one group rather than separate randomized participant arms. This distinction matters: an experimental contrast between treated and mock tissue does not, by itself, establish that participants were assigned to different clinical treatment groups. The record does not report the allocation of samples to assay conditions, whether samples were paired across conditions, or the details of any adjustment for participant-level clustering.

The primary endpoint is a continuous measure, reported as a mean with standard deviation. The registry lists four outcome measures and no analyses. It names secondary outcomes concerning cytokine secretion profiles in adipose tissue depots and adipose cell size distribution in pericardial and subcutaneous tissue. Numerical findings for these outcomes are not reported in the registry record. Further details of the laboratory protocol, analysis population, and 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

Analysis population for the primary outcome, as defined in the registry: Participants with tissue samples analyzable with optimized assays for lipolysis

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: Participants with tissue samples analyzable with optimized assays for lipolysis

6. Primary Endpoint

The registry lists the primary outcome as Rate of Isoproterenol-Stimulated Lipolysis in Adipose Tissue Depots to Measure Metabolic Flexibility, measured over Time to collect tissue collected during surgery (up to 15 minutes).

The primary endpoint is the rate of isoproterenol-stimulated lipolysis in adipose tissue depots, measured in µmol/L/hr. The description says lipolysis was assessed under basal, isoproterenol-stimulated, and insulin-suppressed conditions, using a colorimetric assay. The named depots are epicardial, pericardial, and subcutaneous tissue. The registry describes the endpoint as a measure of metabolic flexibility.

In general, lipolysis is the breakdown of stored fat. Measuring a tissue’s response under different assay conditions can characterize how that tissue responds to stimulation or suppression. Isoproterenol-stimulated lipolysis is therefore relevant to the stated question about metabolic flexibility: it records a response under a specified laboratory stimulus rather than only a resting value. The basal and insulin-suppressed conditions provide additional assay contexts, although the registry does not report their numerical results or explain how they were combined or compared in analysis.

The endpoint is a continuous measurement, and the registry specifies a mean and standard deviation as its summary format. A mean describes the average measured rate in the analyzed samples; a standard deviation describes the spread of individual measurements around that average. These summaries do not, on their own, quantify uncertainty about a difference between conditions. The registry record does not report the primary endpoint values, a contrast between ertugliflozin-treated and mock tissue, a confidence interval, or a statistical test result. The timeframe is tissue collection during surgery, up to 15 minutes; this is not a reported duration of clinical treatment or follow-up.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a continuous primary endpoint summarized by a mean and standard deviation. It also identifies a colorimetric assay for measuring lipolysis. Those details tell readers the type of outcome and the stated measurement approach, but they do not identify the statistical model used to compare tissue conditions. The record lists no analyses and does not report numerical estimates, so the inferential methods and their results cannot be reconstructed from the registry record.

What does a mean describe?

In general, a mean is the arithmetic average of measured values in an analyzed set of samples. It gives a compact description of the level of a continuous outcome, such as lipolysis rate. It does not describe how values are distributed, and it does not show how precisely the mean estimates a broader quantity. The standard deviation describes the spread of observations around the mean. It is not the same as a confidence interval: the standard deviation describes variation among measurements, whereas a confidence interval describes uncertainty in an estimate under specified assumptions.

For this endpoint, the registry states that the summary parameter is a mean and the dispersion measure is a standard deviation. However, it does not report the mean or standard deviation for any tissue depot or assay condition. It also does not report an estimated difference between treated and mock tissue. Without those results, the direction and magnitude of a contrast cannot be evaluated.

What can a comparison between tissue conditions establish?

In general, comparing tissue exposed to an experimental condition with tissue in a mock condition can estimate a difference in the measured assay outcome, if the comparison is defined and analyzed appropriately. The registry refers to ertugliflozin-treated and mock tissue, but does not report how samples were assigned to conditions, whether each participant’s tissue was measured under both conditions, or which contrast was designated for inference. It would be inappropriate to assume a paired analysis or any other specific method.

The study is listed as single group, with allocation not applicable. That design description is consistent with distinguishing the laboratory tissue contrast from a randomized trial between participant groups. The registry does not establish that participants were randomized to clinical treatment or that the in-vitro exposure represents medication use by participants. Interpretation should remain within the tissue assay context that the record describes.

Why do tissue depots and assay conditions matter?

The primary outcome description names epicardial, pericardial, and subcutaneous adipose tissue and refers to basal, isoproterenol-stimulated, and insulin-suppressed conditions. In general, measurements across multiple depots and assay conditions can produce related but distinct outcomes. A statistical analysis needs to specify which outcomes are primary, how contrasts are defined, and how dependencies among measurements are handled. If multiple measurements come from the same participant or tissue source, they may not be statistically independent. The record does not report whether or how that dependence was addressed.

More generally, over-dispersion occurs when observed variability is greater than a statistical model expects. Accounting for it can matter because a model that understates variability may give overly narrow uncertainty intervals or misleading evidence against a null hypothesis. The primary outcome is described as continuous, and the registry does not report a model or evidence of over-dispersion. This is general statistical context, not a claim about an issue observed in this study.

What does the record say about power and planning?

The registry’s planning assumptions describe an illustration based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The stated effect to detect is a fraction of the observed effect. For non-time-to-event outcomes, the assumptions describe participants per arm; the time-to-event convention is not relevant to this continuous endpoint. Such planning values, when available, are illustrations under assumptions. They are not observed power and do not show that the study was designed with those assumptions.

The registry does not report the observed effect needed to interpret an illustration, nor does it report the study’s own sample-size justification. It would therefore be inappropriate to infer the intended design effect, a minimum detectable difference, or whether enrollment was adequate for a particular analysis. The rationale for the enrollment of 61 is not reported in the registry record.

What is missing for a full statistical assessment?

The registry lists no analyses. It does not report confidence intervals, p-values, test procedures, model specifications, adjustment variables, or an analysis population count for each outcome. It also does not report how missing or unusable assay measurements were handled. A complete statistical interpretation would require the outcome values, defined contrasts, uncertainty estimates, and enough analysis detail to understand how the estimates were obtained. These items are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The study lists four outcome measures, including the primary measure of lipolysis and secondary outcomes concerning cytokine secretion profiles and adipose cell size distribution. When a study assesses multiple outcomes, tissue depots, or assay conditions, the number of statistical comparisons can affect how often apparently notable findings occur by chance. In general, multiplicity procedures can define which results are confirmatory or adjust inference across a family of comparisons. The registry does not report whether any such procedure was planned or used.

The analysis count is listed as zero. No analysis results, test statistics, p-values, or confidence intervals are reported in the registry record. It is therefore not possible to determine whether results were adjusted for multiple comparisons, whether a primary contrast was designated among the tissue depots and assay conditions, or how secondary endpoints were treated in the analysis.

The record defines the primary population as participants with tissue samples analyzable using optimized assays for lipolysis. It does not report how many participants met that criterion for each outcome. The number enrolled should not be taken as the number analyzed. The registry also does not report whether the analysis used all available measurements, a subset meeting assay criteria, or another population definition.

Missing data, failed assays, and excluded samples can affect both the size and representativeness of an analyzed set. In general, methods for describing and handling unavailable measurements help readers judge that risk. The registry does not report the amount or reasons for missing outcome data, exclusions, imputation procedures, or sensitivity analyses. These omissions prevent assessment of how missingness might affect estimates. The protocol’s multiplicity strategy, missing-data plan, and analysis-population definitions are not reported in the registry record.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 5% reporting threshold.

The registry’s adverse-event entry lists the treated-tissue group with 61 at risk for serious adverse events and zero affected, 61 at risk for other adverse events and zero affected, and zero deaths. No serious adverse-event terms are listed. These are the counts recorded in the registry, not an analysis of tissue efficacy.

The intervention description is an in-vitro treatment of adipose tissue samples with ertugliflozin at 25 µM. The event figures should therefore be read in the context of the registry entry, not as a direct estimate of risks from participants taking the drug. The record does not explain how events were collected, what observation period applied to adverse events, or how the event categories relate to the laboratory intervention. It also does not provide a detailed adverse-event narrative.

Zero recorded events does not establish that no events could occur, nor does it quantify clinical safety. The registry’s counts report what was entered for this group; they do not replace information about ascertainment or a suitable clinical safety comparison. Further detail on event monitoring and interpretation is not reported in the registry record.

12. What the Result Does, and Does Not, Mean

The study addresses whether ertugliflozin exposure changes properties of adipose tissue in laboratory assays, with particular attention to lipolysis and metabolic flexibility. It describes treatment of tissue samples in vitro and identifies a mock condition for comparison. Its design is registered as single group, rather than as a randomized comparison of participant treatment groups.

The record does not report numerical results for the primary endpoint. It therefore cannot establish the measured lipolysis rates, the size or direction of any difference between treated and mock tissue, or the precision of an estimate. The same applies to the listed secondary outcomes. No statistical tests or analyses are reported in the registry record.

In general, a laboratory tissue result is evidence about the assay and samples examined. It does not by itself establish an effect on clinical outcomes or indicate what would happen when a medication is used by a person. The record’s description of tissue collection during surgery and exposure in vitro defines the experimental context. It does not report clinical treatment allocation or a participant-level treatment comparison.

The enrollment of 61 describes the registered study size, but the number contributing analyzable samples to each endpoint is not reported. Without endpoint-specific sample counts and outcome estimates, readers cannot assess how informative the results are or how well they represent the intended population. The sample-size planning assumptions are explicitly described as an illustration based on an observed effect; they should not be interpreted as observed power or as evidence about the study’s design rationale.

The appropriate conclusion is limited: the registry records a completed early-phase tissue study and specifies its question, intervention, and outcome framework. It does not report the numerical findings needed to determine what the assays showed. The registry record therefore supports neither a quantified claim about an effect nor a clinical conclusion about ertugliflozin.

13. Why This Trial Matters Statistically

This study is statistically interesting because it separates a tissue-level experiment from a conventional comparison of participant groups. The registry identifies a single-group study, while the endpoint description compares tissue cultured with ertugliflozin to a mock condition. Keeping those levels distinct is essential: a laboratory contrast and a clinical treatment effect answer different questions.

The outcome also spans multiple tissue depots and assay conditions. Such designs can generate biologically informative measurements, but they require clear definitions of the comparisons and a plan for dependence among measurements and multiplicity. The record identifies several depots and conditions, but does not report the analysis strategy or numerical estimates. That makes the study’s statistical evidence impossible to assess from the registry record alone.

The record also illustrates why enrollment and analysis counts should not be conflated. It reports enrollment of 61 and defines the primary population by whether tissue samples were analyzable with optimized assays. Endpoint-specific sample counts are not reported, so the effective sample size for each measurement is unknown. For tissue-based research, assay eligibility and usable sample availability are relevant to interpreting the breadth and precision of results.

Finally, the listed planning assumptions are illustrations, not proof of a design choice or of observed power. A reader would need the effect estimate, its uncertainty, and the planned analysis to interpret such planning information. Since those results and analysis details are absent, the registry record is informative about the study’s structure but limited as a source for statistical conclusions.

14. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The main limitation for interpreting this trial record is that numerical results are not reported for the primary endpoint or the named secondary outcomes. Without outcome values, effect estimates, or uncertainty intervals, the direction, magnitude, and precision of any tissue response cannot be assessed. The registry also lists no analyses, leaving the inferential approach unspecified.

The distinction between the single-group study design and the tissue-level mock comparison is important. The record does not report how tissue samples were allocated to assay conditions, whether treated and mock measurements were paired, or how multiple depots and conditions were incorporated into analysis. These details affect the interpretation of comparisons and are not reported in the registry record.

Enrollment is reported as 61, but the number of participants with analyzable samples for each endpoint is not. The record does not report missingness, assay failures, exclusions, or any procedures for handling unavailable measurements. It also does not provide the analysis population for each outcome. Consequently, the relation between enrollment and the measurements underlying any result cannot be evaluated.

The registry names a mean and standard deviation for the primary outcome but gives no estimates, confidence intervals, or test results. Its planning assumptions are described as an illustration based on an observed effect, not as the trial’s own design justification. The observed effect and sample-size rationale are not reported in the registry record.

Finally, the intervention is described as in-vitro exposure of tissue collected during surgery. The record does not describe a randomized clinical treatment comparison or report clinical outcomes. Results from this experimental setting, even if available, would need to be interpreted within that scope. Protocol details, multiplicity procedures, and the missing-data plan are not reported in the registry record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Ertugliflozin: Cardioprotective Effects on Epicardial Fat — NCT04167761.
• Registry record last updated 2026-06-04; status last verified 2026-04.
• Results first posted 2026-06-04.
• 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.

18. Record Summary

The registry describes an EARLY PHASE1, single-group study sponsored by Stanford University. It is marked completed, with enrollment of 61, a start date of 2020-07-01, and a primary completion date of 2023-12-31. The intervention was ertugliflozin applied to adipose tissue samples in vitro at 25 µM.

The primary outcome is the rate of isoproterenol-stimulated lipolysis in adipose tissue depots, summarized as a mean with standard deviation and measured in µmol/L/hr. The endpoint description includes basal, isoproterenol-stimulated, and insulin-suppressed assay conditions and refers to a mock comparison. Secondary outcomes concern cytokine secretion profiles and adipose cell size distribution.

The registry does not report numerical outcome results, analyses, endpoint-specific sample counts, or confidence intervals. It lists zero serious adverse events, zero other adverse events, and zero deaths in the treated-tissue group, but does not provide the details needed to interpret those counts as clinical safety evidence.