A Study to Evaluate the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of PF-06882961 in Japanese Adults With Type 2 Diabetes Mellitus: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study to Evaluate the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of PF-06882961 in Japanese Adults With Type 2 Diabetes Mellitus (NCT04552470), a randomized phase 1 study. The primary outcome is Number of Participants With Treatment Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs).

2. Clinical Question

3. Trial Design

This was a randomized, double-blind, sponsor-open, placebo-controlled, parallel-group Phase 1 study. It enrolled 37 participants and is listed as completed. The registry gives a study start date of 2020-10-26 and a primary completion date of 2021-03-25. The official title describes an 8-week study, while the primary safety observation period extended from Day 1 of dosing to approximately 4 weeks after the last dose, up to a maximum of approximately 12 weeks.

The intervention was oral PF-06882961 administered twice daily. The registry lists groups targeting 40 mg, 80 mg, and 120 mg. Participants in those groups were to be titrated to their desired dose over up to 2 weeks, 4 weeks, and 6 weeks, respectively. A placebo group was also included. The record does not describe titration procedures for placebo or report the allocation ratio.

The stated purpose was to evaluate safety, tolerability, pharmacokinetics, and pharmacodynamics in Japanese adults with type 2 diabetes mellitus. The registry lists pharmacokinetic secondary outcomes for PF-06882961: area under the plasma concentration-time profile from zero to 24 hours (AUC24), maximum observed plasma concentration (Cmax), time to maximum observed concentration (Tmax), and terminal phase half-life (t1/2). The record lists 8 outcome measures, but does not report statistical analyses for them in the results summarized for this trial.

The primary outcome is a safety measure based on counts of participants with treatment-emergent AEs and SAEs. The registry defines the safety analysis set as randomized participants who took at least 1 dose. That population definition is relevant when interpreting the arm counts: enrollment and the safety-set denominators describe different stages of participation. The registry record does not report additional design details such as the allocation ratio or a statistical analysis plan.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Before assignment: 65 participants signed the inform consent form (ICF). 28 participants were screen failures who did not meet criteria and were not enrolled. 37 participants enrolled into the study and assigned to a study treatment.

Overall Study

Analysis population for the primary outcome, as defined in the registry: Safety analysis set included all participants who were randomly assigned to study intervention and who took at least 1 dose of study intervention.

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

Population: Safety analysis set included all participants who were randomly assigned to study intervention and who took at least 1 dose of study intervention.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With Treatment Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs), measured over Day 1 of dosing up to approximately 4 weeks after last dose (up to maximum of approximately 12 weeks).

The primary outcome counts participants with treatment-emergent adverse events and serious adverse events. An AE is defined as an untoward medical occurrence temporally associated with study intervention, whether or not it is considered related to the intervention. An SAE is an AE that results in a specified serious outcome, including death, initial or prolonged inpatient hospitalization, a life-threatening experience, persistent or significant disability or incapacity, or a congenital anomaly, or is deemed significant for another reason.

Treatment-emergent events were those occurring between the first dose and approximately 4 weeks after the last dose that were absent before treatment or worsened relative to the pretreatment state. The registry gives the primary observation window as Day 1 of dosing to approximately 4 weeks after the last dose, up to a maximum of approximately 12 weeks.

Counting participants is a way to describe how many people in each group experienced an event during the defined period. It is used for safety monitoring because it gives a direct account of participants affected, while the event definition also distinguishes serious from non-serious events. The count alone does not describe event severity beyond that classification, timing, recurrence, or whether investigators judged an event to be related to treatment. The registry does not report individual event terms for serious events in the results summarized for this trial.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary endpoint is expressed as a count of participants rather than as a continuous measurement. Each participant is classified according to whether a treatment-emergent AE or SAE was recorded during the defined observation period. The registry gives arm-specific numbers of participants at risk and numbers affected. Those counts can describe the observed safety experience within each group, but they do not by themselves provide an adjusted comparison or quantify uncertainty.

What does a participant count capture? A participant count records whether a person experienced an event, rather than how many separate events that person experienced. This distinction matters because one participant may have more than one event, while the endpoint is framed around participants with events. The registry gives counts for serious and other AEs, but does not supply event-level detail, recurrence counts, or a breakdown by event term in the results summarized for this trial. The counts therefore cannot describe the full pattern of events or how often events recurred.

What is the role of the analysis population? The safety analysis set includes all participants who were randomly assigned to study intervention and took at least 1 dose. This definition excludes randomized participants who did not take a dose, if any, and is distinct from simply describing enrollment. The arm-specific safety denominators are 9 for placebo, 10 for PF-06882961 40 mg, 9 for 80 mg, and 9 for 120 mg. The registry does not report additional analysis populations for the primary safety outcome.

How should group comparisons be assessed? General statistical context: a comparison of event counts can be presented using a difference in risks, a relative measure, or a model-based estimate, but each approach requires a defined comparison and an appropriate analysis. A confidence interval is useful because it communicates the uncertainty around an estimated comparison; a hypothesis-test result addresses compatibility with a specified null hypothesis under model assumptions. The registry does not report such a comparison, confidence interval, or hypothesis test for this primary endpoint. No new comparative estimate should be inferred from the raw counts alone.

General statistical context: sparse safety outcomes can make estimates imprecise, especially when few participants are observed. A zero count in a group is an observed result, not proof that the underlying event probability is zero. Interpretation also depends on the observation period and the completeness of event ascertainment. The registry specifies the treatment-emergent period but does not report a separate analysis of follow-up completeness or precision for the SAE counts.

What do the planning assumptions mean? The registry's sample-size assumptions describe planning illustrations based on fractions of an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. Such calculations are planning illustrations, not observed power. The primary outcome has several categories or time points and was not reduced to one comparison, so those assumptions do not supply a specific primary safety comparison in the registry record. The sample-size justification for the trial itself is not reported in the registry record.

General statistical context: over-dispersion is a feature of count data in which variability exceeds what a simple count model expects. It can affect standard errors and confidence intervals if a count model is used. This endpoint, however, is the number of participants affected, and no count-model analysis or over-dispersion assessment is reported. It would therefore be inappropriate to attribute a particular model or variance assumption to this trial.

The registry lists 0 statistical analyses for the outcomes. It does not report an interim analysis plan, an adjustment method for multiple comparisons, a model for the primary endpoint, or a prespecified hypothesis test. The appropriate interpretation is therefore descriptive: the counts report observed participants with events in each group, without an inferential estimate of treatment effect.

10. Multiplicity, Missing Data and Analysis Populations

The registry describes the primary outcome as having several categories or time points and does not reduce it to one comparison. It does not report a multiplicity adjustment or explain how multiple safety categories, dose groups, or time points were handled in formal inference. Because no primary comparison or inferential analysis is reported, the posted counts should not be interpreted as a set of confirmatory tests.

Missing-data handling is not reported in the registry record. The record defines the safety analysis set as participants who were randomized and took at least 1 dose, but does not describe how missing event information, incomplete follow-up, or withdrawal was handled. The stated event observation period runs from Day 1 of dosing to approximately 4 weeks after the last dose, up to a maximum of approximately 12 weeks; the record does not give further detail about completeness of observation within that window.

The only specified analysis population for the primary safety outcome is the safety analysis set. The registry does not report an intention-to-treat analysis, a per-protocol population, or another population definition for this endpoint. It also lists no statistical analyses for the outcomes. These omissions limit interpretation of statistical uncertainty and prevent assessment of whether analysis decisions could influence the reported counts.

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 0% reporting threshold.

Most frequent non-serious adverse event terms

The SAE counts are 0 participants in placebo, 0 in PF-06882961 40 mg, 0 in PF-06882961 80 mg, and 0 in PF-06882961 120 mg. The safety-set denominators are 9, 10, 9, and 9, respectively. These figures indicate that no participant in the recorded safety groups was reported with an SAE during the stated treatment-emergent observation period.

The registry defines SAEs by outcomes or clinical significance, including death, hospitalization, a life-threatening experience, persistent or significant disability or incapacity, and congenital anomaly. The record lists no serious adverse event terms. A zero participant count does not mean that risk is absent; it means no SAE was recorded among the observed participants in the specified period. The size of the safety groups and the absence of a reported comparative analysis limit how precisely these observations can be generalized.

The counts for other AEs are separate descriptive figures: 3 participants in placebo, 7 in the 40 mg group, 9 in the 80 mg group, and 9 in the 120 mg group. The registry does not provide event terms or a detailed severity breakdown for these counts. Neither the SAE counts nor the other-AE counts establish causation.

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

The results describe treatment-emergent safety observations among participants in the safety analysis set. The record reports no participants with SAEs in any group and reports other AEs in each group, with counts of 3 for placebo, 7 for PF-06882961 40 mg, 9 for 80 mg, and 9 for 120 mg. The observation period began on Day 1 of dosing and continued to approximately 4 weeks after the last dose, with a maximum of approximately 12 weeks.

These findings do not establish whether PF-06882961 caused any event. The registry definition includes AEs whether or not they are considered related to study intervention. It also does not report enough event-level detail to characterize the kinds of other AEs, their timing, or whether individual participants experienced more than one event. The serious-event listing contains no terms, and no statistical analysis or uncertainty interval is reported for the primary outcome.

The counts do not establish a comparative treatment effect, prove that the groups differ, or show that serious events cannot occur. They also do not answer the trial's pharmacokinetic or pharmacodynamic questions: although those outcomes are listed, their results are not reported in the information summarized for this trial. The registry record does not report efficacy outcomes that would support conclusions about clinical benefit.

General statistical context: a safety result is interpreted in light of the number of participants observed, the duration of observation, the definition of an event, and the precision of any comparison. Here the participant counts and observation window are reported, but a comparative estimate and its precision are not. The most defensible reading is therefore descriptive and limited to the recorded safety observations in this study.

13. Why This Trial Matters Statistically

This trial illustrates how a randomized, placebo-controlled study can report safety through participant counts while leaving important questions about comparative inference unanswered. The registry identifies the study as a Phase 1 investigation of safety, tolerability, pharmacokinetics, and pharmacodynamics, and it reports a defined safety population and treatment-emergent observation period. Those details are necessary to understand what the counts represent.

The study also illustrates why an endpoint's structure matters. The primary outcome encompasses treatment-emergent AEs and SAEs and is described as having several categories or time points. The registry does not reduce it to one comparison or report a statistical analysis. Without a specified comparison and an uncertainty estimate, readers should not treat differences in raw counts as formal evidence of a treatment effect.

Small safety groups can make event counts useful for describing what was observed while limiting the precision of conclusions about uncommon events. Zero reported SAEs in the groups is a meaningful description of the observed trial record, but it does not establish absence of risk. Likewise, counts for other AEs cannot be interpreted without information about event terms, severity, attribution, and the analysis approach.

For biostatisticians and clinical researchers, the record underscores the value of transparent reporting of analysis populations, endpoint definitions, missing-data handling, multiplicity decisions, and uncertainty. In this record, the safety-set definition and event window are available, while several analysis details are not reported. The distinction between observed data and inferential conclusions is central to reading these results responsibly.

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 primary safety outcome is not presented as a single comparative estimate. The registry states that it has several categories or time points and does not reduce it to one comparison. No inferential analysis, confidence interval, or p-value is reported, so the precision of differences between groups cannot be assessed from the registry record.

The safety groups were small: the registry reports 9 participants at risk in placebo, 10 in the 40 mg group, 9 in the 80 mg group, and 9 in the 120 mg group. These counts describe the denominator for the posted safety results, but do not by themselves indicate how representative the participants are of other populations. The registry describes Japanese adults with type 2 diabetes inadequately controlled on diet and exercise alone; broader applicability is not established by these results.

The record defines treatment-emergent events and the safety analysis set, but does not report event terms for the other AE counts, detailed severity information, individual event timing, or recurrence. It lists no serious adverse event terms. Missing-data procedures and follow-up completeness are not reported, and the registry does not provide a statistical analysis plan, interim analysis information, or a sample-size justification.

The study's stated scope includes pharmacokinetic and pharmacodynamic outcomes, but their results are not reported in the information summarized for this trial. These limitations mean the available safety counts should be treated as descriptive observations within the defined study population and period, not as a complete account of risk or evidence of comparative effect.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: A Study to Evaluate the Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of PF-06882961 in Japanese Adults With Type 2 Diabetes Mellitus — NCT04552470.
• Registry record last updated 2022-03-11; status last verified 2022-03.
• Results first posted 2022-03-11.
• 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 record describes a completed, randomized, double-blind, sponsor-open, parallel, placebo-controlled Phase 1 study of twice-daily oral PF-06882961 in Japanese adults with type 2 diabetes mellitus. Enrollment was 37. The listed target-dose groups were 40 mg, 80 mg, and 120 mg, with titration over up to 2 weeks, 4 weeks, and 6 weeks, respectively.

The primary outcome counted participants with treatment-emergent AEs and SAEs. The safety analysis set included randomized participants who took at least 1 dose. SAE counts were 0 in each group; other-AE counts were 3, 7, 9, and 9 for placebo, 40 mg, 80 mg, and 120 mg, respectively. The registry does not report an inferential analysis for the primary outcome, missing-data handling, or results for the listed pharmacokinetic and pharmacodynamic measures in the information summarized for this trial.