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 LY2189265 and Sitagliptin in Participants With Type 2 Diabetes (NCT01408888), a randomized phase 1 study. The primary outcome is Pharmacokinetics: Area Under the Concentration Versus Time Curve (AUC) of Sitagliptin.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01408888 |
| Phase | Phase 1 |
| Condition | Diabetes Mellitus, Type 2 |
| Allocation | Randomized |
| Design model | Crossover |
| Masking | None (open label) |
| Enrollment | 29 |
| Arms in the primary outcome | 3 |
| Lead sponsor | Eli Lilly and Company |
| Results posted | Yes |
2. Clinical Question
Population
Participants with type 2 diabetes mellitus who received at least one dose of sitagliptin and had evaluable sitagliptin AUC data. The registry reports enrollment of 29 participants; the primary outcome summaries include 28, 29, and 26 participants, depending on the reported treatment-time condition.
Intervention
Sitagliptin, 100 mg orally once daily, given with LY2189265, 1.5 mg by subcutaneous injection. The record describes LY2189265 doses alongside sitagliptin on Day 5 and Day 12 of Treatment 2.
Comparator
Sitagliptin, 100 mg orally, summarized on Day 4 without LY2189265. The crossover design also included a separate LY2189265 treatment sequence, with a washout of at least 21 days before crossing over.
Primary question
How did sitagliptin AUC over one 24-hour dosing interval compare across the reported sitagliptin-alone and sitagliptin-plus-LY2189265 treatment-time summaries? AUC describes overall drug exposure across the interval; the posted primary outcome reports geometric means and geometric coefficients of variation, not a formal comparative estimate.
The registry describes the study purpose as examining how the drugs affect one another’s absorption and processing. Its posted primary endpoint focuses on sitagliptin exposure. It does not report a primary statistical comparison, a treatment-effect estimate, or a confidence interval for the contrast between conditions. The question addressed by the posted figures is therefore descriptive: what geometric mean AUC values and variability were recorded for each listed condition? Those summaries can inform interpretation of the pharmacokinetic measurements, but they do not by themselves quantify the uncertainty around a difference between conditions.
3. Trial Design
This was a Phase 1, randomized, nonmasked, crossover study of LY2189265 and sitagliptin in participants with type 2 diabetes. The registry reports enrollment of 29 participants and study status as completed. The study began in 2011-08, with primary completion in 2012-04. The stated expected participation duration was approximately 61 days, including two clinic confinements, one of 2 nights and one of 19 nights.
In a crossover study, participants receive more than one treatment condition in a planned sequence, so measurements can be made under different conditions within the same participant. The registry describes a treatment with a single 1.5 mg subcutaneous dose of LY2189265, followed by a washout period of at least 21 days before crossing over. The other condition involved 100 mg of sitagliptin orally once daily for 18 days, with two separate single 1.5 mg doses of LY2189265 administered immediately before sitagliptin doses on Day 5 and Day 12. The record also describes three LY2189265 injections and 18 daily sitagliptin doses.
For the primary endpoint, the registry reports sitagliptin AUC summaries on Day 4, Day 6, and Day 13 of Treatment 2. Day 4 is listed as 100 mg sitagliptin, while Day 6 and Day 13 are listed as sitagliptin combined with 1.5 mg LY2189265. The posted summaries are based on evaluable AUC data, and the number of participants differs across these conditions. The detailed randomization sequence and its implementation are not reported in the registry record. Blinding was not used, as the study is listed as nonmasked. Further details about how the treatment sequence was generated or concealed 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.
First Intervention
| Stage | LY2189265, Sitagliptin + LY2189265 | Sitagliptin + LY2189265, LY2189265 |
|---|---|---|
| STARTED | 18 | 11 |
| Received at Least 1 Dose of Drug | 18 | 11 |
| COMPLETED | 18 | 8 |
| NOT COMPLETED | 0 | 3 |
Reasons for not completing this period:
| Reason | LY2189265, Sitagliptin + LY2189265 | Sitagliptin + LY2189265, LY2189265 |
|---|---|---|
| Adverse Event | 0 | 1 |
| Withdrawal by Subject | 0 | 2 |
Washout of at Least 21 Days
| Stage | LY2189265, Sitagliptin + LY2189265 | Sitagliptin + LY2189265, LY2189265 |
|---|---|---|
| STARTED | 18 | 8 |
| COMPLETED | 18 | 8 |
| NOT COMPLETED | 0 | 0 |
Second Intervention
| Stage | LY2189265, Sitagliptin + LY2189265 | Sitagliptin + LY2189265, LY2189265 |
|---|---|---|
| STARTED | 18 | 8 |
| COMPLETED | 16 | 8 |
| NOT COMPLETED | 2 | 0 |
Reasons for not completing this period:
| Reason | LY2189265, Sitagliptin + LY2189265 | Sitagliptin + LY2189265, LY2189265 |
|---|---|---|
| Withdrawal by Subject | 1 | 0 |
| Adverse Event | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: Participants who received at least one dose of sitagliptin with evaluable sitagliptin AUC data.
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 who received at least one dose of study drug (LY2189265 or Sitagliptin).
| Characteristic | Unit | Entire Study Population |
|---|---|---|
| Participants analysed | 29 | |
| Age, Continuous | years | 52.7 (SD 11.1) |
| Sex: Female, Male: Female | Participants | 10 |
| Sex: Female, Male: Male | Participants | 19 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 5 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 24 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 4 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 14 |
| Race (NIH/OMB): White | Participants | 11 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 29 |
6. Primary Endpoint
The registry lists the primary outcome as Pharmacokinetics: Area Under the Concentration Versus Time Curve (AUC) of Sitagliptin, measured over Predose and up to 24 hours postdose on Day 4, Day 6, and Day 13 of Treatment 2.
| Element | Registry entry |
|---|---|
| Result type | Geometric Mean |
| Measure of spread | Geometric Coefficient of Variation |
| Unit | nanograms times hour/milliliter(ng*h/mL) |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is sitagliptin area under the concentration-versus-time curve during one dosing interval, described as AUC [0-tau] over 24 hours. AUC combines concentration measurements across time into a summary of overall drug exposure during that interval. The endpoint was measured predose and up to 24 hours postdose on Day 4, Day 6, and Day 13 of Treatment 2. The registry reports the unit as nanograms times hour/milliliter (ng*h/mL), and identifies the summary measure as a geometric mean with geometric coefficient of variation.
Pharmacokinetic AUC is used to characterize exposure, rather than a clinical outcome such as symptoms or disease control. Comparing exposure summaries across a drug-alone condition and combination conditions can help describe whether measured concentrations appear different when the other drug is present. That is the general role of this endpoint; the registry record itself does not report a formal comparative treatment effect or an interpretation of the observed values as a drug interaction.
The posted geometric mean AUC values are 3210.0 for 100 mg sitagliptin on Day 4, 3240.0 for 100 mg sitagliptin plus 1.5 mg LY2189265 on Day 6, and 2970.0 for the combination on Day 13. The geometric coefficients of variation are 34.0, 36.0, and 54.0, respectively. These are separate descriptive summaries, with 28, 29, and 26 participants contributing evaluable data. No confidence intervals are reported for these endpoint summaries.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The primary outcome is presented as three geometric mean AUC summaries rather than as one treatment contrast. The sitagliptin-alone Day 4 condition has a reported geometric mean of 3210.0 ng*h/mL, based on 28 participants. The combination condition on Day 6 has a reported geometric mean of 3240.0 ng*h/mL, based on 29 participants. The combination condition on Day 13 has a reported geometric mean of 2970.0 ng*h/mL, based on 26 participants. The reported geometric coefficients of variation are 34.0, 36.0, and 54.0, in that order.
These values describe the observed endpoint summaries. They should not be read as an adjusted or inferential comparison of sitagliptin exposure between treatment conditions. The registry record reports no analysis results for a two-arm comparison, and no p-value, confidence interval, or model-based treatment effect for the primary endpoint is posted. The registry lists no analyses in its analysis count. Consequently, the posted record does not quantify the precision of a between-condition difference or establish whether any apparent numerical variation is compatible with sampling variability.
The time points also matter to interpretation. Day 4 is labeled sitagliptin alone, while Day 6 and Day 13 are labeled combination treatment. The two combination summaries are not presented as a single pooled estimate. The available record does not report a direct statistical comparison between Day 6 and Day 13, nor does it specify an analysis that separates a treatment effect from other time-related changes. Thus, the three values should be read in their stated conditions and time points, not as interchangeable estimates or a simple before-and-after sequence with a quantified effect.
The numbers of evaluable participants differ by condition. That means each geometric mean is calculated from a condition-specific set of participants with evaluable data. The record does not explain why data were unavailable or unevaluable for some participants at particular time points. It also does not report confidence intervals around the geometric means or a method for handling missing pharmacokinetic observations. The differences in sample size therefore limit how confidently the three summaries can be compared from the registry record alone.
The geometric coefficient of variation describes relative variability around a geometric summary. In general, a larger coefficient indicates greater dispersion on the scale used for that summary. Here, the reported values are 34.0 for the Day 4 sitagliptin-alone condition, 36.0 for the Day 6 combination condition, and 54.0 for the Day 13 combination condition. Those values describe variability in the endpoint data, but they are not confidence intervals and do not tell the reader the uncertainty around a treatment contrast.
The study is randomized and crossover, which can allow each participant to contribute information under multiple treatment conditions. In general, within-participant comparisons can account for stable differences between people. However, a valid interpretation depends on the analysis respecting the sequence and repeated measurements, as well as addressing period or carryover considerations when relevant. The registry does not report the statistical model or how these design features were handled. The posted endpoint summaries therefore support a descriptive reading only; they do not allow reconstruction of the sponsor’s inferential analysis or its conclusions.
9. Statistical Methods Explained
What does a geometric mean summarize?
The registry identifies the primary endpoint statistic as a geometric mean. In general, a geometric mean is calculated on a logarithmic scale and then expressed back on the original scale. It is commonly used for pharmacokinetic measurements because concentration and exposure data can be positively skewed, and proportional changes may be more meaningful than equal additive changes. The record does not state the distributional checks or rationale used to select this summary in this study.
The reported geometric mean AUC values are 3210.0, 3240.0, and 2970.0 ng*h/mL for the Day 4, Day 6, and Day 13 conditions, respectively. These are condition-specific summaries, not estimates of a between-condition ratio or difference. In a formal pharmacokinetic comparison, investigators might report a contrast on the log scale and transform it back to an interpretable scale. Such a contrast and its uncertainty are not reported in the registry record.
What does the coefficient of variation add?
The endpoint dispersion measure is the geometric coefficient of variation. In general, a coefficient of variation expresses variability relative to the scale of the measurement, rather than in the original measurement units. For a geometric summary, the corresponding geometric coefficient is used to describe dispersion for log-transformed data. It is not a confidence interval, a standard error, or a measure of how precisely a treatment difference has been estimated.
The registry reports geometric coefficients of variation of 34.0, 36.0, and 54.0 for the three conditions. These values indicate that variability is part of the interpretation, particularly when considering why group summaries alone do not determine the precision of a comparative estimate. No confidence limits for the endpoint are posted. The registry record also does not describe the method used to estimate the coefficients or any diagnostic evaluation of the data distribution.
Why does the crossover structure matter?
In general, a crossover design assigns participants to sequences in which they receive multiple conditions, with a period between treatments intended to reduce lingering effects. Because participants can serve as their own comparator, analyses can focus on within-person changes, which may reduce the influence of stable participant characteristics. This benefit depends on observations being analyzed in a way that accounts for participant, treatment, and period structure.
The registry describes randomized treatment sequences and a washout period of at least 21 days before crossover. It does not report the statistical model, the sequence allocation details, or whether period, sequence, or carryover effects were assessed. These methods are important because a crossover analysis is not necessarily equivalent to comparing separate groups of observations. The posted geometric means do not reveal whether the statistical analysis used paired data or how correlation between measurements from the same participant was handled.
What can be inferred from the posted endpoint summaries?
The available summaries describe the geometric mean AUC for sitagliptin alone on Day 4 and for the sitagliptin-plus-LY2189265 condition on Day 6 and Day 13. They also give the number of participants with evaluable data and a geometric coefficient of variation for each condition. These are useful descriptive statistics, but they do not provide a formal test of the primary question. No p-value, confidence interval, standard error, adjusted estimate, or other comparative analysis is reported in the registry record.
In general, a confidence interval conveys a range of values compatible with the observed data under a specified method, and its width reflects statistical precision. Without a confidence interval or another measure of uncertainty for a contrast, readers cannot determine how precisely the registry estimates a difference between conditions. The spread measure for each condition is not a substitute: it describes individual-level variation rather than uncertainty in a treatment comparison.
The posted summaries also have different evaluable sample sizes: 28, 29, and 26. A participant may contribute data at one time point and not another, but the reason for any missing or unevaluable measurements is not reported in the registry record. In general, missingness can affect both the set of participants represented by each summary and the reliability of comparisons. The registry does not describe any imputation, exclusion, or sensitivity analysis for missing AUC data.
How should statistical significance be read?
No statistical significance result for the primary endpoint is posted. The registry record does not report a p-value for a sitagliptin-alone versus combination contrast, and it does not report a confidence interval for such a contrast. It would therefore be inappropriate to treat the numerical ordering of the three geometric means as evidence of a statistically established difference or similarity.
In general, statistical significance evaluates data against a specified null hypothesis and depends on the analysis, assumptions, and chosen significance threshold. A lack of a posted test is not evidence that no difference exists; it means the registry record does not provide that inferential result. Similarly, a nonsignificant result, if one were reported, would not by itself demonstrate equivalence. Equivalence or noninferiority requires a defined margin and an analysis designed for that purpose; neither is reported in this record.
What do the planning calculations mean?
In general, a sample-size calculation for a future study uses assumptions about the effect to detect, variability, significance level, allocation, and analysis method. It is a planning illustration, not a measure of the probability that the completed study detected an effect. The study’s own sample-size justification is not reported in the registry record. Nor are analysis-specific sample-size outputs reported in the registry record, so no planning figure can be interpreted as the observed power of this study.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one primary endpoint, sitagliptin AUC during one dosing interval, assessed at Day 4, Day 6, and Day 13 of Treatment 2. It also lists four secondary pharmacokinetic outcomes: sitagliptin Tmax, and LY2189265 AUC, Cmax, and Tmax. The record does not state how multiplicity across outcomes or time points was addressed. No multiplicity adjustment, testing hierarchy, or prespecified order for inferential tests is reported in the registry record.
Multiplicity matters in general when several outcomes, comparisons, or time points are tested. Repeated testing can increase the chance of at least one result appearing notable by chance if each test is interpreted independently. Whether adjustment is appropriate depends on the study’s aims and analysis plan. Because the registry does not post comparative tests or a statistical analysis plan, the approach to multiplicity cannot be assessed from the posted record.
The primary outcome population is described as participants who received at least one dose of sitagliptin with evaluable sitagliptin AUC data. The condition-specific sample sizes are 28, 29, and 26. The reasons for differences in evaluable data, the number of participants with missing measurements, and the handling of such observations are not reported in the registry record. No imputation method or sensitivity analysis is described.
The registry does not report a separate intention-to-treat analysis population, a per-protocol population, or criteria for excluding participants from an analysis beyond the stated primary endpoint population description. It also does not report whether all randomized participants completed both crossover periods. These omissions mean the analysis population and potential effects of missing or incomplete data cannot be fully reconstructed from the posted record.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| LY2189265 | 0 | 26 | 0.0% |
| Sitagliptin | 0 | 29 | 0.0% |
| Sitagliptin + LY2189265 | 2 | 29 | 6.9% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 3% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| LY2189265 | 11 of 26 |
| Sitagliptin | 10 of 29 |
| Sitagliptin + LY2189265 | 16 of 29 |
Most frequent serious adverse event terms
| Event term | Organ system | LY2189265 | Sitagliptin | Sitagliptin + LY2189265 |
|---|---|---|---|---|
| Pneumonia bacterial | Infections and infestations | 0 of 26 | 0 of 29 | 1 of 29 |
| Concussion | Injury, poisoning and procedural complications | 0 of 26 | 0 of 29 | 1 of 29 |
| Renal failure acute | Renal and urinary disorders | 0 of 26 | 0 of 29 | 1 of 29 |
Most frequent non-serious adverse event terms
| Event term | Organ system | LY2189265 | Sitagliptin | Sitagliptin + LY2189265 |
|---|---|---|---|---|
| Headache | Nervous system disorders | 4 of 26 | 1 of 29 | 5 of 29 |
| Fatigue | General disorders | 3 of 26 | 1 of 29 | 2 of 29 |
| Hypoglycaemia | Metabolism and nutrition disorders | 1 of 26 | 1 of 29 | 4 of 29 |
| Nausea | Gastrointestinal disorders | 1 of 26 | 0 of 29 | 4 of 29 |
| Decreased appetite | Metabolism and nutrition disorders | 1 of 26 | 0 of 29 | 4 of 29 |
| Vomiting | Gastrointestinal disorders | 1 of 26 | 1 of 29 | 2 of 29 |
| Diarrhoea | Gastrointestinal disorders | 1 of 26 | 0 of 29 | 2 of 29 |
| Dyspepsia | Gastrointestinal disorders | 2 of 26 | 0 of 29 | 1 of 29 |
| Injection site pain | General disorders | 2 of 26 | 0 of 29 | 1 of 29 |
| Abdominal discomfort | Gastrointestinal disorders | 2 of 26 | 0 of 29 | 0 of 29 |
Serious events with the highest arm-level rate: pneumonia bacterial (3.4%), concussion (3.4%), renal failure acute (3.4%).
The posted safety summaries count participants at risk and participants affected in the listed groups. For serious adverse events, the LY2189265 group had 0 affected participants among 26 at risk, the sitagliptin group had 0 among 29, and the sitagliptin-plus-LY2189265 group had 2 among 29. Death counts are not reported in the registry record. These counts describe the entries in the registry; they do not establish whether an event was caused by a study treatment.
The registry also reports other, non-serious adverse-event counts: 11 of 26 participants in the LY2189265 group, 10 of 29 in the sitagliptin group, and 16 of 29 in the combination group were affected. These groups belong to a crossover study, so they should not be treated as separate parallel groups of unique participants or added together to obtain a participant total. The record does not provide the event-level detail needed to assess timing, recurrence, severity beyond the serious/non-serious classification, or treatment attribution for these counts.
The listed serious adverse event terms are Pneumonia bacterial, Concussion, and Renal failure acute, each reported as 3.4%. The registry does not provide further contextual detail for these term percentages in the posted safety summary. In general, adverse-event figures are descriptive safety observations; their interpretation depends on the study population, exposure, follow-up, and event ascertainment. They do not by themselves establish causation or comparative safety.
12. What the Result Does, and Does Not, Mean
The posted results describe sitagliptin AUC under three stated treatment-time conditions in a randomized crossover study. The geometric mean was 3210.0 ng*h/mL for sitagliptin alone on Day 4, 3240.0 ng*h/mL for sitagliptin plus LY2189265 on Day 6, and 2970.0 ng*h/mL for the combination on Day 13. The corresponding geometric coefficients of variation were 34.0, 36.0, and 54.0. These figures provide a descriptive account of the measured exposure and its variability in the participants with evaluable data.
The record does not report a formal comparative estimate, confidence interval, p-value, or analysis model for the primary endpoint. As a result, the posted summaries do not establish the size or precision of a treatment-related change in sitagliptin exposure. Their numerical ordering should not be treated as proof of a difference, equivalence, or absence of an interaction. A formal conclusion would require the relevant analysis and uncertainty estimates, which are not reported in the registry record.
The trial’s purpose included examining the effect of each drug on the pharmacokinetics of the other. The posted primary endpoint addresses sitagliptin AUC, while the listed secondary outcomes include measures of LY2189265 pharmacokinetics. The registry record does not post secondary outcome results or analysis results for a two-arm comparison. Therefore, the listed outcome names alone do not answer the broader pharmacokinetic question.
The crossover design and washout period are relevant to the planned comparison, but the statistical model and handling of repeated observations are not reported. The endpoint summaries are also based on different numbers of evaluable participants, with no account of missing data. These limitations leave uncertainty about the comparability and precision of the descriptive values.
In general, pharmacokinetic summaries characterize drug exposure; they are not, by themselves, measures of clinical benefit or harm. This record does not support medical advice or a conclusion about treatment effectiveness. It documents a small Phase 1 study’s design, endpoint definition, posted AUC summaries, and selected safety counts, while leaving important inferential details unreported.
13. Why This Trial Matters Statistically
This trial illustrates why endpoint summaries and treatment comparisons are not interchangeable. A geometric mean gives a compact description of exposure for each stated condition, while a comparative estimate would quantify the contrast between conditions. The registry posts the former for sitagliptin AUC but not the latter. For statistical readers, that distinction prevents descriptive values from being mistaken for a formal test of a pharmacokinetic effect.
The crossover structure also highlights the importance of analysis details. Repeated measurements on the same participants can be statistically informative, but the interpretation depends on accounting for within-participant association and the sequence of conditions. The record identifies randomization, crossover, and a washout period of at least 21 days, yet does not describe the model or diagnostics used. A reader can understand the planned structure without being able to reproduce or evaluate the inferential analysis.
Variability and evaluable sample sizes further shape interpretation. The geometric coefficients of variation differ across the posted conditions, and the number of participants contributing data is not identical at each time point. In general, a summary of central tendency without uncertainty does not show how precisely a contrast has been estimated. This study therefore provides a useful example of the limits of reading apparent differences directly from point summaries.
The record also separates a pharmacokinetic question from a clinical outcome question. AUC summarizes drug exposure over an interval. It is not itself a measure of how participants felt or functioned, nor does it alone establish treatment benefit, harm, or causality. Statistical interpretation should stay aligned with what the endpoint measures and what analyses are actually reported.
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 registry record contains descriptive primary endpoint summaries but does not report an inferential comparison between sitagliptin alone and the combination conditions. No primary treatment-effect estimate, confidence interval, p-value, or statistical model is reported. As a result, the magnitude and precision of a between-condition contrast cannot be evaluated from the posted results.
Condition-specific evaluable sample sizes differ: 28 on Day 4, 29 on Day 6, and 26 on Day 13. The record does not explain the missing or unevaluable measurements, identify whether participants completed all periods, or describe a missing-data method. This limits assessment of whether the summaries represent comparable participant sets.
The registry identifies the study as randomized and crossover but does not provide the allocation sequence details, analysis of period or sequence effects, or an assessment of carryover. It reports a washout period of at least 21 days, but the rationale for its duration is not reported in the registry record. The method used to account for the repeated observations is also not reported.
The sample-size justification and statistical analysis plan are not reported in the registry record. Neither is an approach to multiplicity across time points and secondary pharmacokinetic outcomes. The registry lists four secondary outcomes but does not post their results. These gaps prevent a fuller assessment of prespecification, selective reporting, and the overall pharmacokinetic findings.
The study enrolled 29 participants and is listed as Phase 1. The registry describes the primary endpoint population as participants with at least one sitagliptin dose and evaluable AUC data. The record does not report additional population criteria or enough detail to establish how broadly the findings apply beyond the study participants and conditions. Safety summaries also lack event-level context and do not state whether events were attributed to treatment.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Study of LY2189265 and Sitagliptin in Participants With Type 2 Diabetes — NCT01408888.
- Registry record last updated 2014-10-07; status last verified 2014-10.
- Results first posted 2014-10-07.
- 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
NCT01408888 is a completed Phase 1 randomized, nonmasked crossover study of LY2189265 and sitagliptin in participants with type 2 diabetes. Enrollment was 29. The study began in 2011-08, and primary completion was in 2012-04. The record describes a washout period of at least 21 days between crossover treatments.
The primary endpoint was sitagliptin AUC over a 24-hour dosing interval, summarized as geometric means and geometric coefficients of variation. The posted values are 3210.0 on Day 4 with sitagliptin alone, 3240.0 on Day 6 with the combination, and 2970.0 on Day 13 with the combination. The corresponding evaluable sample sizes are 28, 29, and 26. No inferential comparison for the primary endpoint is reported in the registry record.
The record lists four secondary pharmacokinetic outcomes and reports selected adverse-event counts. It does not post secondary outcome results, a statistical analysis plan, a sample-size justification, or details of missing-data handling.