Efficacy and Safety Study of MP-513 in Patients With Type 2 Diabetes: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Efficacy and Safety Study of MP-513 in Patients With Type 2 Diabetes (NCT00628212), a randomized phase 2 study. The primary outcome is Change From Baseline in HbA1c at Week 12.

2. Clinical Question

3. Trial Design

This was a phase II, randomized, quadruple-masked, parallel-group study with placebo control. The official title describes it as a double-blind monotherapy study in Japanese patients with type 2 diabetes. The registry lists an enrollment of 324 and a completed status. The study start is recorded as 2008-01, and primary completion as 2008-12.

The four assigned groups were placebo and teneligliptin 10 mg, 20 mg, and 40 mg. Each regimen was taken orally once daily. The brief summary describes a 12-week administration period and identifies change in HbA1c and adverse events as central measures. The primary endpoint timeframe is 12 weeks. The parallel design means the groups represent separate assigned regimens over the study period, rather than a sequence of treatments for each participant.

Randomization is reported, but the method used to generate the assignment sequence, any stratification factors, and the concealment process are not reported in the registry record. Quadruple masking is the recorded designation; the identities of the four masked roles are not reported in the registry record. The record also does not describe adherence procedures, co-intervention restrictions, or the detailed schedule of visits beyond the endpoint timeframe.

The primary endpoint analysis used a full analysis set, defined in the registry as patients who received at least one dose and had at least one efficacy measurement after randomization. It used last observation carried forward for missing postbaseline observations. The registry supplies the numbers analyzed for the endpoint by group, but does not provide a complete account of participant flow or the reasons for missing endpoint data. These details matter when assessing how closely the analyzed groups reflect the randomized groups.

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

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: The full analysis set, consisting of all type 2 diabetic patients, who received at least one dose of study drug and who had at least one efficacy data after randomization. Analysis based on last observation carried forward, where the last postbaseline double-blind observed value was carried forward and used for Week 12 where data was missing.

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.

6. Primary Endpoint

The registry lists the primary outcome as Change From Baseline in HbA1c at Week 12, measured over 12 weeks.

The primary endpoint was change from baseline in HbA1c at week 12, measured in percent. HbA1c represents glucose bound to hemoglobin and is expressed in the registry description as a percent of the absolute maximum that can be bound. It is used as a continuous measure of glycemic status, allowing the analysis to describe both the direction and average magnitude of change over the study period.

The registry reports least squares means rather than only raw group averages. These model-based means came from an analysis of covariance, or ANCOVA, with treatment as a fixed effect and baseline HbA1c as a covariate. Accounting for baseline values can improve the precision of a comparison when baseline measurements are related to follow-up values. The result remains an average change for the analyzed groups; it does not show how every individual participant changed.

The analysis used the last observed postbaseline value carried forward when a later measurement was missing. That approach retains participants with incomplete follow-up, but its interpretation depends on assumptions about what an unobserved later measurement would have been. The registry does not report the reasons for missing measurements or sensitivity analyses using other missing-data approaches. The endpoint addresses change through week 12 and does not, by itself, describe persistence after that assessment or other clinical outcomes.

7. Results Posted in the Registry

• Teneligliptin 10 mg: mean -0.77 versus 0.11 on control; difference -0.88 (95% CI -1.02 to -0.74), standardized effect d = -1.94; z-test p = <0.001.
• Teneligliptin 20 mg: mean -0.80 versus 0.11 on control; difference -0.91 (95% CI -1.05 to -0.77), standardized effect d = -2.04; z-test p = <0.001.
• Teneligliptin 40 mg: mean -0.91 versus 0.11 on control; difference -1.02 (95% CI -1.16 to -0.88), standardized effect d = -2.27; z-test p = <0.001.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Change From Baseline in Fasting Plasma Glucose at Week 12

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • Teneligliptin 10 mg: mean -15.00 versus 2.80 on control; difference -17.80 (95% CI -23.34 to -12.26), standardized effect d = -0.98; z-test p = <0.001.
  • Teneligliptin 20 mg: mean -14.10 versus 2.80 on control; difference -16.90 (95% CI -22.58 to -11.22), standardized effect d = -0.92; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Teneligliptin 10 mg than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Teneligliptin 20 mg than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Change From Baseline in 2-hour Postprandial Plasma Glucose at Week 12

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • Teneligliptin 10 mg: mean -43.30 versus 7.30 on control; difference -50.60 (95% CI -62.80 to -38.40), standardized effect d = -1.27; z-test p = <0.001.
  • Teneligliptin 20 mg: mean -49.40 versus 7.30 on control; difference -56.70 (95% CI -69.17 to -44.23), standardized effect d = -1.41; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Teneligliptin 10 mg than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Teneligliptin 20 mg than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Change From Baseline in the Areas Under the Curve From 0 to 2 h (AUC0-2h) for Postprandial Plasma Glucose at Week 12

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • Teneligliptin 10 mg: mean -65.44 versus 5.90 on control; difference -71.34 (95% CI -88.74 to -53.94), standardized effect d = -1.26; z-test p = <0.001.
  • Teneligliptin 20 mg: mean -73.21 versus 5.90 on control; difference -79.11 (95% CI -96.87 to -61.34), standardized effect d = -1.38; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Teneligliptin 10 mg than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Teneligliptin 20 mg than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The posted secondary outcomes cover fasting plasma glucose, 2-hour postprandial plasma glucose, and the area under the curve for postprandial plasma glucose from 0 to 2 hours, each assessed as change from baseline at week 12. Across the reported group estimates, the placebo means are positive while the teneligliptin means are negative. This broad direction is consistent with the pattern of the primary endpoint: the active groups' reported average changes are lower than the placebo group's on these measures.

The secondary outcomes provide related but distinct views of glucose measurements. Their direction can help describe whether the primary endpoint pattern is accompanied by similar patterns in other recorded measures. They should not be treated as independent confirmation of the primary result: the outcomes arise from the same trial and may be related to one another. The registry lists three secondary endpoints, but reports no formal secondary analyses. The recalculated comparisons are unadjusted, and the record does not provide a multiplicity procedure for secondary outcomes or comparisons.

When several outcomes and treatment contrasts are examined, the chance of finding apparently notable results by chance can increase. Without a prespecified testing hierarchy or adjustment method, unadjusted secondary p-values carry less weight than a result from a clearly specified primary analysis. In this record, the primary endpoint has a described ANCOVA method, while the secondary analysis details are limited. The secondary pattern is therefore best read as descriptive context for the primary endpoint, not as a separate basis for firm confirmatory conclusions. The registry record does not report whether these secondary endpoints were designated as confirmatory or exploratory in the protocol.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Change From Baseline in Fasting Plasma Glucose at Week 12
• Change From Baseline in 2-hour Postprandial Plasma Glucose at Week 12
• Change From Baseline in the Areas Under the Curve From 0 to 2 h (AUC0-2h) for Postprandial Plasma Glucose at Week 12

9. Statistical Interpretation

10. Statistical Methods Explained

The registry describes the primary endpoint as a continuous outcome and reports least squares mean changes with standard errors. The primary model was ANCOVA, with treatment as a fixed effect and baseline HbA1c as a covariate. The registry does not report the full model specification, diagnostic checks, or the detailed method used to estimate uncertainty.

What does a least squares mean represent?

A least squares mean is a model-based group mean. In this analysis, ANCOVA accounts for baseline HbA1c while estimating the mean change associated with each assigned treatment. This differs from simply averaging each group's observed changes without adjustment. The adjustment is useful when baseline values vary and are associated with follow-up measurements, but the estimate depends on the model being appropriate for the data. The reported values are still averages and do not describe the range of individual responses.

What does the standard error describe?

A standard error quantifies the estimated sampling uncertainty of a statistic, such as a group mean. It reflects how precisely the mean is estimated under the statistical model. It is not the spread of individual participant measurements. The primary endpoint standard errors are 0.05 in each reported group. A confidence interval uses an estimate and its uncertainty to express a range of values compatible with the data and the interval procedure. It does not give the probability that a particular fixed effect lies in the realized interval.

How were the posted comparisons calculated?

The pairwise contrasts listed for the endpoint are recalculated, unadjusted comparisons between each active group and placebo. For example, the posted comparison for teneligliptin 10 mg is -0.88, with a 95% confidence interval from -1.019 to -0.741 and p < 0.001. The comparable estimates for 20 mg and 40 mg are -0.91 and -1.02, each with p < 0.001. These recalculations use the posted group means and standard errors to approximate group variability. Because that variability is reconstructed approximately, and because the contrasts are not the stated ANCOVA treatment contrasts, the recalculated intervals and p-values should not be mistaken for sponsor-reported model results. The registry does not report the treatment contrasts from its ANCOVA model.

A p-value summarizes how inconsistent the observed data, or more extreme data, would be with a specified null model if its assumptions held. It is not the probability that the null hypothesis is true, and it does not measure the size or practical importance of an effect. Here, the listed p-values are unadjusted, so they do not account for testing multiple treatment comparisons or endpoints.

Why does over-dispersion matter?

In general, over-dispersion means that data vary more than a statistical model expects. When a model underestimates variability, standard errors can be too small and confidence intervals too narrow; when it overestimates variability, precision can be understated. This is a general statistical consideration, not a reported finding about this trial. The registry does not report a formal assessment of dispersion or model diagnostics for the primary endpoint.

How was missing information handled?

The primary analysis used last observation carried forward: the last observed postbaseline value was used in place of a later missing value. This procedure gives an analysis value to a participant without a week-12 observation, but treats the earlier value as if it represented the later assessment. If participants' outcomes would have changed after their last observed visit, that substitution can misrepresent the week-12 value. The registry does not report reasons for missing data, the amount of missingness by group, or sensitivity analyses that test alternative assumptions.

The full analysis set included patients who received at least one dose and had at least one efficacy measurement after randomization. This definition excludes randomized participants who did not meet those conditions. The registry does not report a separate intention-to-treat analysis or a per-protocol analysis. General statistical interpretation should therefore keep the stated population and missing-data method in view rather than assuming that the estimates include every randomized participant under all possible follow-up scenarios.

What can planning estimates tell a reader?

The sample-size illustrations use two-sided significance level 0.05, equal allocation between the two arms, and a normal approximation. They examine detecting the stated fraction of the observed effect and give participants per arm for non-time-to-event outcomes. These figures are planning scenarios based on the observed effect, not the trial's documented design calculation. The original sample-size justification and planning assumptions are not reported in the registry record. A smaller effect generally requires more participants to detect at the same power and significance level, all else being equal.

11. Confidence Intervals and Precision

Precision is reflected by the standard errors and confidence intervals, but the two types of uncertainty summaries in the registry should be kept distinct. For the primary endpoint, the reported standard error is 0.05 in each group. These standard errors accompany the ANCOVA least squares means and describe uncertainty in those model-based mean changes. The registry does not report confidence intervals for those ANCOVA means or their treatment contrasts.

The comparison intervals are recalculated and unadjusted. The estimate for teneligliptin 10 mg versus placebo is -0.88, with a 95% confidence interval from -1.019 to -0.741. For 20 mg, the estimate is -0.91, with an interval from -1.049 to -0.771. For 40 mg, the estimate is -1.02, with an interval from -1.159 to -0.881. Each interval is based on an approximate standard deviation reconstructed from posted means and standard errors. This approximation and the unadjusted method mean the intervals are not equivalent to model-based intervals from the registry's ANCOVA.

A confidence interval gives a range of effect estimates compatible with the data under the calculation's assumptions and method. Narrower intervals indicate greater statistical precision under those assumptions, while wider intervals indicate more uncertainty. An interval excluding zero in an unadjusted comparison is not, on its own, a complete inferential conclusion: it does not account for multiple comparisons, model uncertainty, or missing-data assumptions. Precision is also not the same as clinical importance. The registry does not report a threshold for a clinically important difference in HbA1c, so the clinical meaning of the interval widths cannot be established from this record alone.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The sample-size figures are planning illustrations expressed as participants per arm, not total event counts. They are based on the observed effect and consider detecting the full observed effect, 75% of the observed effect, or 50% of the observed effect. The stated assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. These illustrations are separate from the trial's original design calculation, which is not reported in the registry record.

The 80% power column gives the planned participants per arm for a hypothetical study with an 80% chance of detecting the specified effect under the stated assumptions, if that effect is real and the model assumptions hold. The 90% power column gives the corresponding planning figure for a 90% chance. Neither column describes the probability that the trial's observed result is true, and the figures do not demonstrate the power achieved by the completed study.

The rows use different target effects. Planning for 75% of the observed effect requires more participants per arm than planning for the full observed effect in the listed illustrations; planning for 50% requires more again. This reflects a general principle: smaller effects are harder to distinguish from random variation and therefore need more participants when other assumptions remain fixed. These estimates are sensitive to the effect and variability used, and the observed effect may not be a reliable value for planning a future study. They should be read as scenarios rather than prescriptions or evidence of the original trial's sample-size rationale. This is not observed power.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = -0.880; pooled standard deviation σ = 0.453.
2. n = 2 × (1.96 + 0.842)² × 0.453² / -0.880² = 4.2, rounded up to 5 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- -0.88                      # observed difference in means
sigma <- 0.452905571604196                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(628212)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 5 (80% power), 6 (90% power)
 75% of observed effect: n per arm = 8 (80% power), 10 (90% power)
 50% of observed effect: n per arm = 17 (80% power), 23 (90% power)
power.t.test: 5.3 
Simulated power at n = 5 per arm: 0.768 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when statistical tests are conducted across several outcomes, treatment groups, or comparisons. The primary endpoint includes comparisons of three teneligliptin groups with placebo, and the registry also lists three secondary endpoints. The posted recalculated p-values are unadjusted. A multiplicity adjustment or a prespecified testing hierarchy is not reported in the registry record. Accordingly, the unadjusted p-values should not be read as controlling the overall chance of a false-positive finding across all the comparisons that may have been considered.

The primary analysis population is described as the full analysis set: patients who received at least one dose and had at least one efficacy measurement after randomization. The primary outcome used last observation carried forward for missing postbaseline values. The registry does not report the number or reasons for missing week-12 observations, a participant flow accounting, or sensitivity analyses using other missing-data assumptions. This limits assessment of whether the stated method materially influenced the endpoint estimates.

The registry identifies ANCOVA with treatment as a fixed effect and baseline HbA1c as a covariate, but does not report a fuller statistical analysis plan, diagnostic results, or the sponsor's model-based treatment contrasts. The specific original sample-size justification, interim analyses, and the trial's multiplicity strategy are not reported in the registry record. These are gaps in the available record; they do not establish that such procedures were absent from the trial protocol or conduct.

Last observation carried forward is a specific assumption about missing outcomes, not a neutral way to recover an unobserved week-12 measurement. If the recorded outcome would have changed after the last observed visit, carrying the earlier value forward can create bias. Without missing-data details and sensitivity analyses, the robustness of the result to alternative assumptions cannot be assessed from the registry alone.

15. Safety Results

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

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: metastatic neoplasm (1.2%).

The registry reports serious adverse events as counts of affected participants and the corresponding group at-risk counts. There was 1 serious adverse event among 80 participants in the placebo group. The reported counts were 0 among 84 in the teneligliptin 10 mg group, 0 among 79 in the 20 mg group, and 0 among 81 in the 40 mg group. These are observed counts during the study, not estimates that establish the relative safety of the regimens.

The registry lists “Metastatic neoplasm” as a top serious-event term, with 1.2%. The record does not provide enough context in this entry to assign that term to a specific group or describe its clinical course. Death counts are not reported in the registry record. The other adverse-event counts are separate from the serious-event counts and should not be combined with them.

Zero recorded serious events in an active group does not prove that the risk is zero; uncommon events may not appear in a study of this size and duration. The study lasted 12 weeks for the primary endpoint, so the posted figures describe events recorded in this trial rather than longer-term safety. These counts alone do not determine whether an event was caused by a study treatment.

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

The posted primary endpoint estimates show a difference in the direction of change between the placebo group and each teneligliptin group at week 12. The reported least squares mean changes were 0.11 for placebo and -0.77, -0.8, and -0.91 for teneligliptin 10 mg, 20 mg, and 40 mg, respectively. The registry's primary analysis used ANCOVA with baseline HbA1c as a covariate. The simple recalculated comparisons also show negative mean differences versus placebo, with unadjusted p-values of <0.001.

These results describe a short-term average change in the analysis population. They do not show the response of every individual, establish that the differences are clinically important, or tell how outcomes may change beyond week 12. A statistical difference and a clinically meaningful difference are not interchangeable. The registry does not report a clinically important threshold for HbA1c change.

The results also do not establish the relative merits of the three teneligliptin doses. The group means are descriptive, but direct active-dose comparisons are not reported in the registry record. A pattern across doses is not itself a formal dose-response analysis. The recalculated intervals and p-values are unadjusted and based on an approximate standard deviation, so they should not be substituted for sponsor-reported ANCOVA contrasts.

Safety interpretation is similarly bounded. The serious adverse event counts are sparse and describe observed events in the study groups; they cannot establish that no less common or longer-term risks exist. Nor can the counts alone attribute an event to treatment. Overall, the registry gives information about one phase II study, its selected endpoints, and its 12-week analysis. It does not by itself answer broader questions about durability, other outcomes, or applicability to populations not described in the record.

17. Why This Trial Matters Statistically

This trial is statistically informative because it reports a randomized, placebo-controlled comparison across three assigned doses and gives a defined primary endpoint. The primary measure is continuous, and the registry describes an ANCOVA model that includes baseline HbA1c. Those details help readers understand the target quantity: adjusted average change from baseline at week 12, rather than a count of participants who crossed a threshold.

The record also makes the analysis population and missing-data method visible. The full analysis set required at least one dose and at least one post-randomization efficacy measurement, and missing postbaseline values were handled by carrying the last observed value forward. Knowing these choices matters because the group estimates are conditional on them. The method has assumptions that cannot be fully checked from the registry entry, particularly without information on missingness and sensitivity analyses.

Another useful distinction is between the registry's stated ANCOVA analysis and the unadjusted recalculations based on posted group summaries. The latter provide approximate contrasts and intervals, but they do not recreate the sponsor's full model. Keeping these separate prevents a precise-looking recalculated interval from being mistaken for an official adjusted result.

Finally, the study illustrates why statistical significance, estimation precision, multiplicity, and clinical importance should be considered separately. The reported unadjusted p-values are small, but the record does not report a multiplicity plan or a threshold for clinical importance. The sample-size illustrations are planning scenarios based on observed effects, not the trial's original design calculation. Each detail contributes to a careful reading without extending the conclusions beyond the trial's endpoint, population, and follow-up.

18. Limitations

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

The primary endpoint is limited to change in HbA1c at week 12. The registry does not report longer-term follow-up results in the registry record described for this record. Its full analysis set excludes patients without a dose or without any post-randomization efficacy data, and the registry does not provide a participant flow description or reasons for missing data. Last observation carried forward may not represent an unobserved week-12 value if the outcome would have changed over time.

Although an ANCOVA model is described, model-based treatment contrasts and confidence intervals are not reported. The posted pairwise comparisons are unadjusted recalculations with an approximate standard deviation; they are not a substitute for the sponsor's ANCOVA contrasts. A multiplicity strategy is not reported, and there are several active-versus-placebo comparisons alongside secondary outcomes. The record therefore leaves uncertainty about how the analyses were prioritized and how the chance of false-positive findings was handled.

The registry reports group-level averages, not individual response distributions. It does not report a clinically important threshold for the primary endpoint, so the clinical importance of the estimated changes cannot be judged from these values alone. It also does not report direct comparisons among active doses, making the dose pattern descriptive rather than a demonstrated difference between doses.

The study is identified as phase II and lasted 12 weeks for the primary outcome. The record's findings should not be extended to durability or outcomes not reported. Details about randomization procedures, masking roles, missing-data sensitivity analyses, interim analyses, and the original sample-size rationale are not reported in the registry record. Their absence from this record limits appraisal but does not establish what the full protocol contained.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Efficacy and Safety Study of MP-513 in Patients With Type 2 Diabetes — NCT00628212.
• Registry record last updated 2026-01-02; status last verified 2025-12.
• Results first posted 2013-05-31.
• 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.

22. Record Summary

NCT00628212 is a completed, randomized, quadruple-masked, parallel, placebo-controlled phase II study of teneligliptin in Japanese patients with type 2 diabetes. The four assigned regimens were placebo and teneligliptin 10 mg, 20 mg, and 40 mg, taken orally once daily. The registry lists an enrollment of 324.

The primary endpoint was change from baseline in HbA1c at week 12. The registry reports ANCOVA least squares means and standard errors for the full analysis set, using last observation carried forward for missing postbaseline observations. Recalculated unadjusted comparisons show negative mean differences for each active group versus placebo, but they are approximate and are not the sponsor's ANCOVA contrasts. Three secondary glucose outcomes and adverse-event counts are also recorded. Multiplicity procedures, missing-data sensitivity analyses, and the original sample-size justification are not reported in the registry record.