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 Safety and Tolerability Study of Aripiprazole IM Depot in Adult Subjects With Schizophrenia (NCT01909466), a randomized phase 1 study. The primary outcome is Number of Participants With Adverse Events (AEs)..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01909466 |
| Phase | Phase 1 |
| Condition | Schizophrenia, Mental Disorder, Nervous System Diseases |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 141 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Otsuka Pharmaceutical Development & Commercialization, Inc. |
| Results posted | Yes |
2. Clinical Question
Population
Adults with schizophrenia were the intended study population. The registry reports enrollment of 141 participants. The safety population was defined as randomized participants who received at least one dose of study medication, regardless of protocol violations. The posted safety group has 138 participants at risk. Further eligibility criteria and participant characteristics are not reported in the registry record.
Intervention
The study evaluated multiple-dose aripiprazole intramuscular depot administered in the deltoid muscle. The intervention is listed as aripiprazole, also identified as OPC-14597. The adverse-event result is labeled “Aripiprazole IM Depot 400 mg - Total.” Details of the dosing schedule are not reported in the registry record.
Comparator
The registry describes a randomized parallel study and lists Deltoid Injection and Gluteal Injection arms. The arm descriptions are blank, and the posted primary adverse-event result is for the total group rather than separate arms. The specific contrast, including the doses and schedules assigned to each arm, is not reported in the registry record.
Primary question
The primary outcome asks how many participants experienced adverse events during the study safety observation period. The registry defines an adverse event as a new medical problem or worsening of an existing problem during trial participation, whether or not the investigator considered it related to study medication. The result is a safety count, not an estimate of comparative efficacy.
The registry’s stated purpose was to determine the safety and tolerability of multiple-dose aripiprazole intramuscular depot administered in the deltoid muscle in adults with schizophrenia. That purpose frames the primary outcome: whether participants experienced medical events while enrolled, including events not judged to be drug-related. The event count therefore concerns observed safety experience during the specified observation period; by itself, it does not establish that the medication caused an event.
Although randomization and a parallel model are recorded, the primary outcome result is posted for a total group rather than as a comparison between the listed injection arms. No arm-specific primary outcome counts or statistical comparison are reported in the registry record. The clinical question that can be answered from the posted primary result is consequently descriptive: how many participants in the reported group had events, not whether one injection site had a different event rate from another.
3. Trial Design
This is a completed Phase 1 study with randomized allocation, no masking, and a parallel model. It enrolled 141 participants. The recorded study start is 2013-07, and primary completion is recorded as 2014-03. The registry identifies adults with schizophrenia as the study population and lists Otsuka Pharmaceutical Development & Commercialization, Inc. as sponsor.
The official title describes an open-label, multiple-dose study of aripiprazole intramuscular depot administered in the deltoid muscle. The intervention list identifies aripiprazole, OPC-14597. The registry lists Deltoid Injection and Gluteal Injection arms, but their descriptions are blank. The adverse-event result is presented for “Aripiprazole IM Depot 400 mg - Total,” with no separate primary outcome result by arm. Dosing schedules, treatment duration, and the precise arm assignments are not reported in the registry record.
Open-label means masking was not used: participants and study staff were not described as unaware of the assigned intervention. In general, knowledge of treatment assignment can influence the reporting, elicitation, or interpretation of subjective outcomes, although the degree of influence on a particular outcome cannot be determined from design labels alone. Randomization is intended in general to support comparable groups at allocation, but the registry record does not report the allocation procedure or the arm-specific baseline information needed to assess balance.
The safety population included randomized participants who received at least one dose of study medication, regardless of protocol violation. The posted adverse-event group has 138 participants at risk, whereas total enrollment is 141. The reasons for this difference and the number randomized to each arm are not reported in the registry record. The primary outcome concerns adverse events recorded from informed consent through follow-up for 28 days after last; what “last” refers to in the truncated timeframe description is not reported in the registry record.
The registry lists 17 outcome measures, including the primary adverse-event count and secondary measures of symptom severity, clinical global ratings, and subject well-being. Numerical results for those secondary outcomes are not reported in the registry record. The record reports zero analyses, so no inferential analysis results are posted.
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: Prior to the trial, the participants were stabilized for at least 14 days on their current oral antipsychotic medication prior to administration of the first aripiprazole IM depot.
Overall Study
| Stage | Gluteal/Deltoid | Deltoid/Deltoid |
|---|---|---|
| STARTED | 68 | 73 |
| COMPLETED | 46 | 50 |
| NOT COMPLETED | 22 | 23 |
Reasons for not completing this period:
| Reason | Gluteal/Deltoid | Deltoid/Deltoid |
|---|---|---|
| Lost to Follow-up | 5 | 7 |
| Adverse Event | 3 | 4 |
| Met Withdrawal Criteria | 0 | 3 |
| Physician Decision | 2 | 0 |
| Withdrawal by Subject | 11 | 9 |
| Lack of Efficacy | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: The safety sample included all randomized participants who were administered at least one dose of study medication, regardless of any protocol violation.
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.
| Characteristic | Unit | Aripiprazole IM Depot 400 mg - Total |
|---|---|---|
| Participants analysed | 141 | |
| Age, Continuous | Years | 43.9 (SD 10.2) |
| Sex: Female, Male: Female | Participants | 32 |
| Sex: Female, Male: Male | Participants | 109 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants With Adverse Events (AEs)., measured over AEs were recorded from the time the informed consent was signed until follow-up for 28 days after last.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants with adverse events. It counts people who experienced at least one event rather than counting every event episode. The registry defines an adverse event as any new medical problem or worsening of an existing problem experienced while a participant was enrolled, whether or not the investigator considered it related to study medication.
The endpoint is used to describe safety experience during the study observation period. Its broad definition allows the registry to capture events without first requiring a judgment that the study medication caused them. The endpoint includes the period from signing informed consent through follow-up for 28 days after last, although the timeframe wording does not identify what was last. The complete endpoint schedule is not reported in the registry record.
A serious adverse event is defined separately as an untoward medical occurrence resulting in death, being life threatening, requiring inpatient hospitalization, or prolonging hospitalization. A treatment-emergent adverse event has a separate definition based on starting after study medication or worsening from baseline in specified circumstances. These distinctions matter because an overall adverse-event count and a serious-event count describe different aspects of safety.
Counting participants is straightforward to interpret as a measure of how many people were affected in the observed group. It does not convey how many events each person experienced, the duration or severity of events beyond the separate serious-event classification, or whether an event was caused by treatment. The primary outcome is also not a direct measure of symptom benefit. Although symptom and well-being outcomes are listed as secondary measures, their numerical results are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry reports 4 participants with serious adverse events among 138 at risk in the total aripiprazole intramuscular depot group. It reports 112 participants with other adverse events among the same 138 at risk. These are descriptive counts for the posted group. They do not, on their own, indicate whether events were more or less frequent with deltoid versus gluteal injection, because arm-specific primary outcome counts are not reported in the registry record.
The serious-event terms listed among the leading terms are Schizophrenia at 1.4%, Atrial fibrillation at 0.7%, and Psychotic disorder at 0.7%. These entries describe terms recorded in the registry adverse-event information. The registry record does not report an event-by-event narrative, the severity of each event beyond the serious classification, or the investigators’ causal assessments for these terms.
The count of participants with adverse events should not be read as a count of events. A participant may experience more than one event, while the participant-level endpoint counts that person once for the outcome. The record also separates serious events from other events. The two figures therefore represent different reported categories, rather than a complete event-by-event account. Further detail on event timing, recurrence, and participant overlap is not reported in the registry record.
The study was randomized, but the posted safety result is pooled across the total group. Randomization alone does not turn a pooled count into a comparative estimate. Without arm-specific counts, an effect estimate, or an inferential analysis, the registry record does not establish the direction or size of any difference between injection arms. No confidence interval or p-value for the primary outcome is reported in the registry record.
The registry lists symptom, global-impression, and well-being outcomes, but does not post their numerical results. The primary endpoint is a safety measure, and the available result does not answer whether symptoms changed or whether one administration site performed differently. The study purpose and posted safety counts should therefore be interpreted within the limits of the data available in the registry record.
In general, a confidence interval expresses the uncertainty around an estimated effect under a statistical model; it is not reported for this primary result. In general, a p-value evaluates how compatible data are with a specified null hypothesis under stated assumptions; no primary-outcome p-value or testing procedure is reported. The posted counts are useful descriptive information, but do not provide those inferential summaries.
9. Statistical Methods Explained
What does a participant count represent?
The primary outcome is a participant-level count: it records how many people had an adverse event, not the total number of events. This distinction is important when a person may have multiple events. The registry’s posted total group has 138 participants at risk, with 4 participants reported with serious adverse events and 112 with other adverse events. These counts do not show how many separate event episodes occurred.
In general, a count is most interpretable alongside its denominator and a clear definition of who could be included. Here the safety population is defined as all randomized participants who received at least one dose, regardless of protocol violation. This differs conceptually from a population that includes every randomized participant whether or not treatment began. Reasons that participants were not part of the posted safety group are not reported in the registry record.
How do the event definitions shape interpretation?
The registry defines an adverse event broadly as a new medical problem or worsening of an existing problem during enrollment, regardless of whether the investigator judged it related to medication. This approach captures events that occur during observation without requiring a causal attribution. It does not mean every recorded event was caused by the study drug.
The serious adverse-event definition is based on specified consequences: death, a life-threatening occurrence, inpatient hospitalization, or prolonged hospitalization. The treatment-emergent definition identifies events beginning after study medication or certain worsening events that continued from baseline. These definitions classify events in different ways. The registry’s primary endpoint is the number of participants with adverse events, while the posted safety information separately reports serious and other event categories.
What can randomization and masking tell the reader?
Random allocation and a parallel model are recorded. In general, randomization is designed to reduce systematic differences between treatment groups at the time of allocation. Its value for a comparative question depends on knowing the assigned groups, how participants were allocated, and how outcomes are reported by group. The registry lists Deltoid Injection and Gluteal Injection arms, but the arm descriptions are blank and the primary safety result is posted only for the total group. Arm-specific primary results and the allocation procedure are not reported in the registry record.
Masking is recorded as none, consistent with the open-label title. In general, lack of masking can affect subjective reports or assessments because expectations may be known. Whether that occurred for any particular adverse event cannot be determined from the registry data. The endpoint’s broad medical-event definition and investigator judgment of drug relatedness are relevant context, but they do not establish bias in the reported count.
What does statistical precision mean for these results?
In general, a point estimate is a single summary of observed data, while a confidence interval describes uncertainty around that estimate under specified assumptions. For a binary participant outcome, an analysis might report the proportion of participants experiencing an event and an interval, or compare proportions across arms. The registry record posts participant counts but does not report a confidence interval, a comparative effect estimate, or a p-value for the primary outcome. No new estimates are calculated from the posted counts in this explanation.
In general, statistical precision depends on factors such as the number of observations, the frequency of the outcome, and the analysis model. A count from a single pooled group does not quantify comparative precision between arms. The posted sample-size assumptions describe a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation. Such illustrations are not observed power and do not substitute for a reported primary analysis. The record does not provide a usable primary-outcome comparison for that illustration, and no planning result for this binary endpoint is reported.
Over-dispersion is a general issue for count data when variability exceeds what a chosen count model assumes. It can lead to uncertainty estimates that are too narrow if ignored. The primary endpoint is a participant count for a binary event status, not a reported count of repeated event episodes; the registry record does not report a model for over-dispersion or a repeated-event analysis.
How should the registry’s analysis information be read?
The registry lists 17 outcome measures and zero analyses. This means numerical analysis results for the listed outcomes are not reported in the registry record. The listed secondary outcomes include changes in PANSS scores, Clinical Global Impression scores, and Subject Well-being Under Neuroleptic Treatment-Short Form scores. No baseline values, follow-up estimates, variability measures, or statistical comparisons for those outcomes are posted in the record.
In general, the distinction between a prespecified outcome and a reported analysis matters. An outcome description tells the reader what was intended to be assessed, while an analysis result supplies the observed estimate and its uncertainty. The registry record gives the primary outcome definition and some safety counts, but does not provide a full inferential analysis plan or results. The analysis model, handling of repeated observations, adjustment variables, and any interim analyses are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 17 outcome measures: a primary adverse-event measure and secondary outcomes covering PANSS symptom scores, Clinical Global Impression ratings, and subject well-being. It reports zero analyses. Numerical results for the secondary outcomes, and inferential results for the primary outcome, are not reported in the registry record.
In general, testing many outcomes can increase the chance of obtaining at least one apparently notable result by chance. Statistical methods may address this through a prespecified hierarchy, adjusted significance thresholds, or other strategies. The registry record does not report whether multiplicity adjustment was planned or used, how outcomes were ordered for testing, or which outcomes were considered confirmatory. No multiplicity procedure should therefore be inferred from the list of outcomes alone.
The registry defines a safety population comprising randomized participants who received at least one dose. It does not report participant flow by arm, reasons for not receiving treatment, missing outcome counts, or a missing-data strategy. It is therefore not possible to determine from the record how incomplete observations were handled or whether the posted group represents all eligible observations at every follow-up point.
In general, missing data can affect interpretation when the likelihood of an outcome being unobserved is related to participant characteristics or outcomes. Common analytic approaches depend on the type and extent of missingness and on assumptions that should be stated. The registry record does not report such assumptions, imputation methods, sensitivity analyses, or the number of participants contributing to each listed secondary outcome.
The record also does not report interim analyses, stopping rules, or a detailed statistical analysis plan. These items are not established by the study’s randomized or Phase 1 design labels. Without analysis details and arm-specific outcome results, multiplicity and missing-data decisions cannot be evaluated for their effect on a treatment comparison.
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 |
|---|---|---|---|
| Aripiprazole IM Depot 400 mg - Total | 4 | 138 | 2.9% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Aripiprazole IM Depot 400 mg - Total | 112 of 138 |
Most frequent serious adverse event terms
| Event term | Organ system | Aripiprazole IM Depot 400 mg - Total |
|---|---|---|
| Schizophrenia | Psychiatric disorders | 2 of 138 |
| Atrial fibrillation | Cardiac disorders | 1 of 138 |
| Psychotic disorder | Psychiatric disorders | 1 of 138 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Aripiprazole IM Depot 400 mg - Total |
|---|---|---|
| Injection site pain | General disorders | 38 of 138 |
| Weight increased | Investigations | 17 of 138 |
| Headache | Nervous system disorders | 16 of 138 |
| Toothache | Gastrointestinal disorders | 11 of 138 |
| Upper respiratory tract infection | Infections and infestations | 11 of 138 |
| Akathisia | Nervous system disorders | 11 of 138 |
| Dyspepsia | Gastrointestinal disorders | 9 of 138 |
| Nausea | Gastrointestinal disorders | 9 of 138 |
| Restlessness | Psychiatric disorders | 8 of 138 |
| Diarrhoea | Gastrointestinal disorders | 7 of 138 |
Serious events with the highest arm-level rate: schizophrenia (1.4%), atrial fibrillation (0.7%), psychotic disorder (0.7%).
The registry reports 4 participants with serious adverse events among 138 at risk in the total group labeled “Aripiprazole IM Depot 400 mg - Total.” It separately reports 112 participants with other adverse events among 138 at risk. The figures are participant counts, not counts of every event episode. The registry’s serious-event definition includes occurrences resulting in death, being life threatening, requiring inpatient hospitalization, or prolonging hospitalization.
The listed leading serious-event terms are Schizophrenia at 1.4%, Atrial fibrillation at 0.7%, and Psychotic disorder at 0.7%. The registry does not provide an event narrative or indicate in these entries whether investigators considered each event related to study medication. The adverse-event definition explicitly includes events whether or not investigators judged them drug-related.
These data describe the reported safety experience in the total group. They are not arm-specific comparisons, and they do not establish that treatment caused the events. The registry record does not report participant-level overlap between serious and other event categories, event duration, recurrence, or detailed outcomes after an event. The timeframe is described as extending through follow-up for 28 days after last, but the meaning of “last” is not stated in the registry record.
12. What the Result Does, and Does Not, Mean
The posted results establish that the registry contains a total-group safety count for a study of multiple-dose aripiprazole intramuscular depot in adults with schizophrenia. In the group labeled “Aripiprazole IM Depot 400 mg - Total,” the record reports 4 participants with serious adverse events and 112 with other adverse events among 138 at risk. These are descriptive observations under the registry’s event definitions.
The counts do not establish causation. An adverse event was recorded whether or not the investigator considered it related to study medication. The serious-event classification describes specified consequences of an event, not a causal relationship. The registry record also does not provide enough detail to determine how the listed serious terms unfolded for individual participants.
The counts do not establish a difference between deltoid and gluteal injection. Although the study is recorded as randomized and parallel and lists both injection arms, the posted primary outcome result is pooled. Arm-specific counts and a comparative statistical analysis are not reported in the registry record. A total-group count cannot answer which arm had a higher or lower event frequency.
The primary safety result does not establish a change in schizophrenia symptoms or well-being. Those domains appear among the listed secondary outcomes, but their numerical results are not reported in the registry record. Nor does the record report a confidence interval or p-value for the primary endpoint, so the statistical precision of a comparative effect cannot be assessed.
In general, a trial result is most informative when the outcome definition, analysis population, group-level estimates, uncertainty, and missing-data handling can all be examined. The registry record gives an outcome definition and a total-group safety count, but does not report several of those details. The appropriate reading is therefore limited to the observed safety counts and the study design information recorded, without extending the result to causal or comparative conclusions.
13. Why This Trial Matters Statistically
This trial is statistically informative as an example of the difference between a randomized design and a reported comparative result. Randomization is recorded, and two injection arms are listed, but the primary adverse-event information is reported for the total group. Without arm-specific counts or an effect estimate, the posted result remains descriptive rather than a comparison of injection sites.
The endpoint also illustrates why outcome definitions and analysis populations matter. The primary measure counts participants with adverse events, while the record defines safety inclusion as randomized participants who received at least one dose. The reported group has 138 participants at risk, compared with enrollment of 141. That difference cannot be explained from the registry record, and it cautions against treating enrollment and the safety denominator as interchangeable.
The record distinguishes general adverse events, serious adverse events, and treatment-emergent adverse events. Those definitions address different classification questions: whether an event occurred, whether it met serious criteria, and whether its timing or change from baseline met the treatment-emergent definition. Clear distinctions help readers avoid treating a broad event count as equivalent to a count of serious events or medication-related events.
Finally, the record lists multiple symptom and well-being outcomes but does not report their numerical analyses. This highlights the difference between outcomes named in a trial record and outcomes with results available for statistical interpretation. The result is useful for describing the registry’s safety reporting, while also showing why full group-level estimates, analysis methods, and uncertainty are needed to support broader comparisons.
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 result is reported only for the total group. Although the registry lists Deltoid Injection and Gluteal Injection arms, the arm descriptions are blank and arm-specific primary outcome counts are not reported. The record therefore does not support a comparison between injection sites based on the posted primary result.
The safety denominator is 138, while total enrollment is 141. The registry defines the safety population as randomized participants who received at least one dose, but does not explain why the remaining enrolled participants are not included in the posted safety group. Randomized numbers by arm, treatment exposure, and participant flow are not reported in the registry record.
The study is open-label and has no masking recorded. This design feature is relevant to outcomes that depend on reporting or assessment, but the registry record does not show whether or how it affected event ascertainment. The record also does not provide event narratives, detailed causality assessments, or the overlap between participants with serious and other adverse events.
The timeframe says events were recorded from informed consent through follow-up for 28 days after last, but the endpoint wording does not identify what was last. The full observation schedule and treatment duration are not reported in the registry record. The record also does not report arm-specific baseline characteristics, eligibility details, a detailed statistical analysis plan, interim analyses, or missing-data methods.
Although 17 outcome measures are listed, zero analyses are reported. Numerical results for secondary symptom and well-being outcomes are not available in the registry record, and no confidence interval or p-value is posted for the primary result. These omissions limit assessment of statistical precision, multiplicity, and comparative effects.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Safety and Tolerability Study of Aripiprazole IM Depot in Adult Subjects With Schizophrenia — NCT01909466.
- Registry record last updated 2015-07-01; status last verified 2015-06.
- Results first posted 2015-06-02.
- 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
The registry record describes a completed Phase 1, randomized, open-label, parallel study of multiple-dose aripiprazole intramuscular depot in adults with schizophrenia. Enrollment was 141. The recorded start was 2013-07, and primary completion was 2014-03. Deltoid Injection and Gluteal Injection arms are listed, with no arm descriptions.
The primary outcome is the number of participants with adverse events. The safety population includes randomized participants who received at least one dose. For the total group labeled “Aripiprazole IM Depot 400 mg - Total,” 138 participants were at risk; 4 participants had serious adverse events and 112 had other adverse events. Serious-event terms listed include Schizophrenia at 1.4%, Atrial fibrillation at 0.7%, and Psychotic disorder at 0.7%.
The registry lists 17 outcome measures and zero analyses. Arm-specific primary results, numerical secondary outcome results, comparative estimates, and inferential statistics are not reported in the registry record.