Drug Use Investigation Of Effexor (SECONDARY DATA COLLECTION STUDY; SAFETY AND EFFICACY OF EFFEXOR.UNDER JAPANESE MEDICAL PRACTICE): Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Drug Use Investigation Of Effexor (SECONDARY DATA COLLECTION STUDY; SAFETY AND EFFICACY OF EFFEXOR.UNDER JAPANESE MEDICAL PRACTICE) (NCT02958527), a registered phase not stated study. The primary outcome is Number of Participants With Adverse Drug Reactions.

2. Clinical Question

The investigation concerns safety and efficacy in routine Japanese medical practice, but the posted primary endpoint is a safety count: participants with adverse drug reactions. An adverse drug reaction was defined as an untoward medical occurrence attributed to Effexor in a participant who received it. The physician assessed whether an occurrence was related to the drug. A serious adverse drug reaction was defined by specified serious outcomes or by the physician deeming it significant for another reason.

The registry also lists secondary outcomes involving changes from baseline in HAM-D17 and MADRS scores at pre-specified evaluation points, Clinical Global Impressions-Severity, and changes in Clinical Global Impressions-Improvement. These measures address symptom severity and clinical improvement, but the registry record does not provide their numerical results in the registry record described for this analysis. The central statistical question is therefore descriptive: what adverse-reaction counts are posted for the treated safety population, and how should those counts be interpreted without a comparator or a reported analysis plan?

3. Trial Design

This is a completed drug-use investigation of Effexor SR Capsules, with venlafaxine listed as the drug intervention. Its title describes secondary data collection and safety and efficacy under Japanese medical practice. The registry lists depression or depressed state as the condition and an enrollment of 1408.

The arm description refers to patients with no experience using Effexor who would receive it for the first time. No comparator arm is described. The record does not describe this as a randomized comparison, and allocation is not stated. Accordingly, the design information supports a description of treated participants and their recorded outcomes, not a direct comparison between assigned treatment groups.

The registry status is completed. The recorded start date is 2016-10-03, and the primary completion date is 2020-05-11. The primary endpoint is the number of participants with adverse drug reactions. Its timeframe is stated as 12 weeks from the start date, up until 52 weeks. The safety analysis set is defined as participants who met the inclusion criteria and received Effexor at least once.

The registry lists five outcome measures and names secondary measures concerning HAM-D17, MADRS, and Clinical Global Impressions. It reports zero statistical analyses. Details about the protocol, the rationale for enrollment, interim analyses, and a fuller statistical analysis plan are not reported in the registry record. The sponsor entry states that Pfizer's Upjohn has merged with Mylan to form Viatris Inc.

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 safety analysis set comprised of participants who satisfied the inclusion criteria and had received Effexor at least once.

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: A total of 1408 participants were enrolled in this study. Of the 1396 participants who completed the study, 62 participants were excluded from the safety analysis set due to the following reasons: no adverse event information (no visit after first day of treatment)(57 participants), no drug administration (3 participants), protocol violation (2 participants).

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With Adverse Drug Reactions, measured over 12 weeks from the start date (up until 52 weeks).

The primary endpoint is the number of participants with adverse drug reactions attributed to Effexor. It is a count-based, binary-participant endpoint: each participant is classified according to whether an attributed reaction was recorded, and the endpoint counts participants with such a reaction. The registry defines an adverse drug reaction as an untoward medical occurrence attributed to Effexor in someone who received it. The physician assessed relatedness.

The registry distinguishes serious adverse drug reactions by their consequences or clinical significance. A serious reaction could involve death, a life-threatening experience, initial or prolonged inpatient hospitalization, persistent or significant disability or incapacity, or congenital anomaly; it could also be deemed significant for another reason. This seriousness definition concerns the nature and consequence of an event, while the primary endpoint concerns the count of participants with reactions.

A count is useful for describing how many treated participants had recorded reactions in the defined safety population and follow-up period. It does not, by itself, establish how the observed experience compares with what would have occurred without Effexor or under another treatment. Nor does a count show how precisely the underlying frequency is estimated unless uncertainty measures are also reported. No confidence interval for the primary endpoint is included in the registry entries. The timeframe is stated as 12 weeks from the start date, up until 52 weeks; further detail about how follow-up duration varied or was handled is not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies the primary outcome as a number of participants with adverse drug reactions, so the outcome is naturally read as binary at the participant level: a participant either had a qualifying reaction recorded or did not. The posted summary gives counts rather than a continuous measurement. For this type of endpoint, a count conveys how many participants were classified as having an event; a proportion would additionally relate that count to a defined denominator. The registry lists 1334 at risk in the venlafaxine group, along with the serious and other affected-participant counts.

What does a confidence interval add?

In general, a confidence interval expresses statistical uncertainty around an estimate. It gives a range of values that are compatible with the data and the method used, rather than only a single point estimate. For a binary outcome, the interval depends on the event count, denominator, and chosen calculation method. No confidence interval for the primary endpoint is reported in the registry entries, so the precision of the posted counts cannot be fully assessed from those counts alone. A count may be clear as a description of the observed safety set while remaining insufficient to show the uncertainty around a broader underlying rate.

Why does the absence of a comparator matter?

A treatment comparison requires groups that can meaningfully be contrasted. The record describes venlafaxine and does not describe a comparator arm; it also states that this is not a randomized comparison and that allocation is not stated. Consequently, the adverse-reaction counts are descriptive of the treated group. They cannot by themselves estimate a contrast between treatment strategies, separate treatment effects from other explanations, or show what would have happened to the same participants under a different approach.

Randomization is a general design method for making treatment groups comparable on average, including on factors that are not measured. It is not described for this investigation. This does not invalidate descriptive reporting, but it limits the causal conclusions that can be drawn from group counts. In routine-practice investigations, differences in patient characteristics, clinical decisions, follow-up, and recording can influence observed outcomes; whether and how those factors were addressed is not reported in the registry record.

How should the event categories be read?

The registry defines adverse drug reactions through attribution to Effexor, with relatedness assessed by the physician. Seriousness is defined by specified consequences or clinical significance. The summary reports serious and other reaction counts separately. Without an explicit statement about overlap or participant-level classification, those categories should not be recombined. The serious-term percentages are listed for individual terms, but the record does not provide enough information to infer event overlap, recurrent events, or the total number of distinct participants represented by every term.

In general, over-dispersion matters when event data vary more than a statistical model assumes. For example, repeated events from the same participant or uneven risk across participants can make simple models understate uncertainty if they treat observations as more independent or homogeneous than they are. The registry entries do not describe a model for recurrent events, participant clustering, or over-dispersion, and the primary endpoint is a participant count rather than a reported recurrent-event analysis. Whether such methods were considered is not reported in the registry record.

What does the sample-size illustration represent?

The planning illustration is not the trial’s design justification and is not observed power. The stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect to detect expressed as a fraction of the observed effect. The record’s comparison is not randomized and does not describe a comparator arm, so those assumptions should not be mistaken for the actual investigation’s design. The illustration is a planning exercise, not evidence that the study had a particular probability of detecting an effect. The trial’s own sample-size justification is not reported in the registry record.

More generally, sample-size planning estimates how many participants a future or hypothetical design might require under stated assumptions. It does not describe the number of events actually observed, and it does not repair the limitations of a non-comparative record. A planning result depends on the assumed effect, variability, significance criterion, allocation, and analysis method. The illustration’s assumptions should therefore be kept distinct from the registry’s enrollment of 1408 and the safety analysis set of 1334.

The registry reports zero statistical analyses. It does not report the methods used to estimate uncertainty, adjust for confounding, handle repeated observations, or compare outcomes. No recalculated treatment comparison is presented in the registry record described for this analysis. The appropriate reading is consequently descriptive: the record reports participant counts and term percentages, while the inferential methods and their assumptions are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists five outcome measures, including a primary adverse drug reaction endpoint and secondary outcomes involving HAM-D17, MADRS, and Clinical Global Impressions. When several outcomes or evaluation points are examined, multiplicity can arise because repeated statistical tests increase the chance of at least one apparently notable result by chance. In general, a prespecified approach may control or otherwise address that issue. The record does not report a multiplicity strategy, the handling of multiple evaluation points, or inferential results for the listed secondary outcomes.

The registry reports zero statistical analyses. It does not describe an analysis plan for missing outcome data, incomplete follow-up, withdrawals, or participants who did not contribute every assessment. Those procedures are not reported in the registry record. Their absence from the record does not show that no procedures were used; it means the registry entries do not establish what they were.

The safety analysis set is defined as participants who met inclusion criteria and received Effexor at least once. Overall enrollment is 1408, and the safety set contains 1334 participants at risk. The reason the populations differ is not reported in the registry record. The registry entries also do not specify analysis populations for the symptom and clinical-impression outcomes, or explain whether all enrolled participants were included in those analyses.

These reporting gaps matter because the population included, the treatment of missing measurements, and the choice of multiplicity procedures can affect interpretation. Without those details, the adverse-event counts remain interpretable as posted descriptive figures for the stated safety set, but the record does not support a fuller assessment of outcome completeness or confirmatory statistical inference.

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 0.1% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: depression (0.1%), suicidal ideation (0.1%), alcoholic pancreatitis (0.1%), jaundice cholestatic (0.1%), liver disorder (0.1%).

The adverse-event summary lists 1334 participants at risk in the venlafaxine group. Within that summary, 20 participants are listed with serious adverse drug reactions and 495 with other adverse drug reactions; the listed death count is 0. These are registry-posted counts, not results from a comparison with a control group.

The serious terms listed are Depression, Suicidal ideation, Alcoholic pancreatitis, Jaundice cholestatic, Liver disorder, and Anaphylactic shock. Each is displayed with 0.1%. The record does not clarify whether a participant could appear under more than one term, whether terms refer to distinct events or participants, or how recurrent events were counted. The term percentages should therefore be read as the posted values for those terms, not as a complete breakdown that can be summed.

Seriousness and drug relatedness are separate judgments in the registry definitions. Seriousness reflects outcomes such as hospitalization or a life-threatening experience, or another reason considered significant; relatedness to Effexor was assessed by a physician. These counts are useful for describing recorded safety experience, but they do not establish that every occurrence was caused by the drug or quantify comparative risk. No confidence interval or control-group estimate is reported in the registry entries.

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

The posted results describe adverse drug reaction counts among participants who received Effexor and qualified for the safety analysis set. They provide a record of how many participants were listed in serious and other reaction categories, along with selected serious-reaction terms and a death count. This is useful descriptive information about the registry’s recorded safety experience.

The results do not establish a causal effect. The registry describes no comparator arm, and this was not a randomized comparison. A treated-group count cannot show how the same population would have fared under another treatment or without treatment. Physician assessment of relatedness is part of the adverse-reaction definition, but the record does not provide individual assessments or the information needed to independently evaluate them.

The figures also do not establish a complete risk profile. The registry entries do not specify how missing observations, follow-up variation, repeated events, or overlap among terms were handled. No confidence interval or statistical analysis is reported. Thus, the counts do not quantify statistical precision, and the listed serious terms should not be treated as an exhaustive description of all possible reactions.

The listed secondary outcomes concern depression symptom scales and clinical impressions, but their numerical results are not included in the registry record described for this analysis. The record therefore cannot support an interpretation of change in those measures. Nor does the sample-size planning illustration establish observed power or show that the investigation was designed to test a treatment contrast; its assumptions are hypothetical and include equal allocation between two arms, unlike the described single-arm record.

In short, the evidence supports a limited descriptive statement about recorded adverse reactions in the safety set. Broader conclusions about comparative safety, causation, symptom change, or how well the estimates represent other populations are not established by these registry entries.

13. Why This Trial Matters Statistically

This investigation is statistically instructive because it places a clearly defined safety outcome in a routine-practice drug-use setting while leaving important inferential details unreported. The primary endpoint is a participant count, and the registry gives an explicit safety population definition. Those features make the basic descriptive question understandable: how many qualifying participants were recorded with reactions attributed to the drug?

At the same time, a descriptive count and a treatment comparison answer different questions. The record does not describe a comparator arm, and it is not a randomized comparison. The posted data therefore illustrate why the presence of event counts should not be mistaken for evidence of a comparative treatment effect. A count can describe observed experience, but causal or comparative claims require additional design and analysis support.

The distinction between serious and other reactions also illustrates how endpoint definitions shape interpretation. Seriousness is tied to specified outcomes or clinical judgment, while drug relatedness is separately assessed by a physician. Readers need those definitions to understand what the counts represent, but the registry does not provide the detail needed to examine every classification or participant-level overlap.

Finally, the record highlights the importance of reporting analysis populations, missing-data handling, uncertainty estimates, multiplicity procedures, and a statistical plan. The registry lists secondary measures and a planning illustration, yet reports no statistical analyses. A planning calculation based on an assumed comparison does not substitute for a design description or analysis of observed data. The result is a useful example of how registry reporting can support a bounded descriptive reading while leaving broader statistical questions unresolved.

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 record describes a single venlafaxine arm and no comparator. It is not a randomized comparison, and allocation is not stated. Consequently, the adverse-reaction counts cannot be interpreted as a between-treatment effect or as a causal estimate. The record does not provide a control group against which the observed safety experience could be contrasted.

Enrollment is 1408, while 1334 participants are listed at risk in the safety group. The reason for this difference is not reported in the registry record. Although the safety-set definition is stated, the record does not report how participants who did not meet the criteria, did not receive the drug, or had incomplete follow-up were handled in other analyses.

The follow-up timeframe is expressed as 12 weeks from the start date, up until 52 weeks. Further details about timing, duration across participants, and how events outside or within evaluation windows were treated are not reported. The record also does not describe event recurrence, overlap between serious and other categories, or whether multiple listed terms could refer to the same participant.

No confidence interval, inferential test, statistical model, missing-data procedure, or multiplicity approach is reported in the registry entries. The listed secondary outcomes do not have numerical results in the registry record described for this analysis. The trial’s own sample-size justification and any interim analyses are also not reported in the registry record. These limitations restrict the interpretation to the posted descriptive safety counts and do not support a broader assessment of efficacy, precision, or comparative safety.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Drug Use Investigation Of Effexor (SECONDARY DATA COLLECTION STUDY; SAFETY AND EFFICACY OF EFFEXOR.UNDER JAPANESE MEDICAL PRACTICE) — NCT02958527.
• Registry record last updated 2023-05-22; status last verified 2021-06.
• Results first posted 2021-05-24.
• 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 drug-use investigation of Effexor SR Capsules (venlafaxine) under Japanese medical practice for depression or depressed state. Enrollment is 1408. The recorded start date is 2016-10-03, and the primary completion date is 2020-05-11.

The primary outcome is the number of participants with adverse drug reactions, with a stated timeframe of 12 weeks from the start date, up until 52 weeks. The safety analysis set includes eligible participants who received Effexor at least once. The adverse-event summary lists 1334 at risk, 20 with serious reactions, 495 with other reactions, and 0 deaths. Six serious-reaction terms are listed, each with 0.1%.

The record lists five outcome measures and zero statistical analyses. It does not describe a comparator arm or a randomized comparison. The posted safety counts are therefore descriptive; further information about analysis methods, missing data, and comparative effects is not reported in the registry record.