A Study to Assess Adverse Events of Intramuscular AGN-151586 Injection in Adult Participants With Glabellar Lines: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study to Assess Adverse Events of Intramuscular AGN-151586 Injection in Adult Participants With Glabellar Lines (NCT05248893), a na phase 3 study. The primary outcome is Number of Participants With Adverse Events.

2. Clinical Question

The study was designed to evaluate safety during up to three treatments, but the registry’s posted primary endpoint description does not give a numerical overall count of participants with any adverse event. The adverse-event categories reported by dose group provide additional descriptive safety information, including serious events and other events. These counts should be read in the context of the open-label, single-group design and the fact that participants could receive different numbers of doses. The record does not establish a causal effect of treatment from these summaries.

3. Trial Design

This is a completed Phase 3, multicenter, open-label, single-group study of intramuscular AGN-151586 for glabellar lines. AbbVie is listed as the sponsor. The study began on 2022-02-25, reached primary completion on 2023-06-26, and its status is completed. The registry lists enrollment as 992. Its brief description anticipated approximately 45 sites in the United States and an enrollment range of around 940 to 1100 adults with moderate to severe glabellar lines.

All participants were scheduled to receive 5 injections into the glabellar complex on Day 1. Participants meeting retreatment criteria could receive up to 2 additional open-label doses. The registry describes regular study-site visits and safety monitoring through medical assessments, blood tests, telephone calls, questionnaires, and checks for side effects. The primary endpoint timeframe runs from Day 1 (Baseline) to Day 126.

There was no masking, and allocation is listed as not applicable. Although the registry displays adverse-event counts for participants categorized by whether they received one, two, or three doses, these categories do not constitute randomized comparison arms. The registry explicitly cautions that the arms are not a like-for-like control comparison. The not-treated category is also not a randomized control group. Differences in the number of doses may reflect retreatment eligibility and exposure rather than assigned study groups.

The safety population included all participants who received at least one dose of AGN-151586, listed as n=985. The record does not report a separate efficacy comparison or a randomized treatment allocation. A statistical analysis plan, sample-size justification, interim analysis details, and further protocol information are not reported in the registry record. The design supports descriptive reporting of observed safety events; it does not, by itself, isolate treatment effects from other explanations for those events.

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: A total of 992 participants were enrolled and 985 received treatment.

All Enrolled Participants (ITT)

Reasons for not completing this period:

AGN-151586 (Dose 1)

Reasons for not completing this period:

AGN-151586 (Dose 2)

Reasons for not completing this period:

AGN-151586 (Dose 3)

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: The safety population included all participants who received at least one dose of AGN-151586 (n=985).

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: Baseline analyses were performed on the ITT Population, consisting of all enrolled subjects (N=992).

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With Adverse Events, measured over Day 1 (Baseline) to Day 126.

The primary endpoint is the number of participants with adverse events during the period from Day 1 (Baseline) to Day 126. It is a count of participants experiencing an event, rather than a count of every event occurrence. A participant with multiple events may still contribute as one participant to an endpoint defined this way. The registry’s description defines an adverse event as an untoward medical occurrence in a participant administered a pharmaceutical product, without requiring a causal relationship to treatment. The investigator assesses the relationship of each event to study drug.

Safety endpoints of this kind are used to describe what medical events arise while participants are followed during treatment. They can help characterize the types and seriousness of events observed and whether investigators consider an event related to study drug. They do not establish causation simply because an event occurred after dosing. In an open-label study, participant and investigator knowledge of treatment may also affect reporting or assessment; the record does not quantify such effects.

The primary endpoint’s definition and timeframe are reported, and the safety population is described as participants receiving at least one dose. However, the overall numerical primary endpoint result is not reported in the registry record. The separate dose-group summaries report serious and other adverse-event counts, but those categories should not be substituted for an overall count of participants with any adverse event.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The appropriate starting point for interpreting this study is its design. It is an open-label, single-group Phase 3 study, with no masking and no randomized allocation. The adverse-event summaries are organized by dose received, but those categories are not randomized comparison groups. The registry specifically cautions that they are not a like-for-like control comparison. Statistical language about treatment differences should therefore be avoided unless an appropriate comparison and analysis are reported.

What does a participant count represent?

The primary endpoint counts participants with adverse events during the stated follow-up window. This differs from counting all event episodes: a person may experience more than one event, while a participant-based endpoint counts whether the person experienced an event. The posted primary endpoint description does not include the overall numerical count, so the event frequency for the full safety population cannot be stated. Separate serious and other adverse-event counts are available by dose category and should be kept distinct from that overall endpoint.

A denominator gives the number of participants in the group being described. For example, the serious and other event summaries list both participants at risk and participants affected within the dose categories. These category denominators describe their respective summaries; they should not be added together to construct a total or treated as randomized arms. The registry lists a safety population of n=985, defined as participants who received at least one dose. The record does not report enough detail to reconcile that population with every displayed category, and no reconciliation should be inferred.

Why does the absence of randomization matter?

Randomization is a method for assigning participants to comparison groups in a way intended to reduce systematic differences between groups. This study does not have randomized assignment. Participants receiving additional doses had to meet retreatment criteria, so dose categories can differ in ways related to eligibility, follow-up, or observed clinical circumstances. The registry does not report a causal analysis that adjusts for such differences. A direct contrast of their raw counts would therefore not isolate the effect of dose number.

In general, open-label means participants and study personnel are not masked to the treatment. This can matter to event recognition, reporting, and investigator judgments of relatedness. It does not mean that reported events are invalid; it means the design and assessment context belong in the interpretation. The registry’s definition explicitly allows an adverse event to occur without a causal relationship to treatment.

How should uncertainty be understood?

In general, a confidence interval describes a range of values compatible with the observed data under a specified statistical procedure. Its width conveys precision, and its interpretation depends on the design and assumptions used. A p-value, in general, describes how unusual data at least as extreme as those observed would be under a stated null model. Neither a confidence interval nor a p-value for the reported adverse-event categories is reported in the registry record. The descriptive counts alone do not quantify uncertainty around a difference between treatment groups.

Over-dispersion is a general issue for count data when variability exceeds what a simple count model assumes. It can affect standard errors and confidence intervals if event counts are modeled using a distribution that does not accommodate the extra variability. The posted summaries are participant counts, and the registry record does not describe a count model or report an over-dispersion assessment. This concept should not be mistaken for an analysis performed in this study.

What do planning illustrations mean?

Any sample-size illustrations associated with these results are planning calculations, not observed trial outcomes and not observed power. The described assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is expressed as a fraction of the observed effect. For non-time-to-event calculations, such illustrations refer to participants per arm for a specified power level. Time-to-event calculations instead describe a total number of events under the stated approach. These are general planning scenarios and are not the study’s own design justification.

The registry record does not report the original sample-size justification or a statistical plan supporting those calculations. Since the study was single-group and nonrandomized, equal allocation between two arms is not a description of its enrollment design. The illustrations should not be read as evidence that the trial had a particular probability of detecting an effect, nor as a substitute for a prespecified analysis. A formal power value for the completed study is not reported in the registry record.

What analyses are actually reported?

The registry lists 7 outcome measures and 0 analyses. This means the record does not provide a set of posted inferential analysis results for interpreting the safety counts. The available summaries can be read as descriptive information, with their definitions, denominators, dose categories, and limitations kept in view. Adjusted estimates, model-based comparisons, confidence intervals, p-values, and details of a prespecified statistical analysis are not reported in the registry record.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("AGN-151586 (Dose 1)", "AGN-151586 (Dose 2)", "AGN-151586 (Dose 3)", "Any AGN-151586")
n      <- c(985, 916, 846, 985)
events <- c(213, 174, 128, 374)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  AGN-151586 (Dose 1)  985  213  21.6  19.1  24.3  19.2  24.3  19.2  24.3
ARM  AGN-151586 (Dose 2)  916  174  19.0  16.5  21.7  16.6  21.7  16.6  21.7
ARM  AGN-151586 (Dose 3)  846  128  15.1  12.8  17.7  12.9  17.7  12.9  17.7
ARM  Any AGN-151586  985  374  38.0  34.9  41.1  35.0  41.0  35.0  41.0

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 7 outcome measures, while 0 analyses are listed. A statistical plan describing how those outcomes were prioritized or analyzed is not reported in the registry record. In general, when many outcomes or comparisons are tested, the chance of at least one apparently unusual result can increase. Methods for addressing multiplicity may include prespecifying a primary outcome or adjusting inference across tests, but the registry information does not state whether such methods were planned or used. No multiplicity-adjusted analysis is reported.

The safety population is defined as all participants who received at least one dose of AGN-151586, n=985. The primary endpoint runs from Day 1 (Baseline) to Day 126. The record does not report the number of participants with missing primary endpoint data, how missing observations were handled, whether follow-up was complete, or how withdrawal and loss to follow-up were addressed. Those details are not reported in the registry record and should not be assumed.

The endpoint counts participants with adverse events, while the adverse-event summary also separates serious from other events and describes dose categories. Definitions of these categories and the investigator’s role in assessing relationship are stated. A detailed coding procedure, rules for repeated events, and a statistical method for handling incomplete event reports are not reported in the registry record.

The registry provides a safety population rather than a reported intention-to-treat comparison population. Because the study is single-group and not randomized, the usual interpretation of randomized-group analysis populations does not apply in the same way. Further analysis-population definitions, protocol deviations, and sensitivity analyses are not reported in the registry record. These omissions limit assessment of how robust the posted descriptive counts are to missing data or analytic choices.

12. 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 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: biliary dilatation (1.4%), cholecystitis acute (1.4%), device related infection (1.4%), jaw fracture (1.4%), rib fracture (1.4%).

The serious-event summaries count participants with serious adverse events within each listed category. The registry reports 3 of 69 in the AGN-151586 one-dose category and 4 of 846 in the three-dose category. It reports 0 of 70 in the two-dose category and 0 of 7 in the not-treated category. These are category-specific counts, not randomized comparisons. The registry also lists 0 deaths in each category.

Other adverse events are reported separately: 11 of 69 in the one-dose category, 9 of 70 in the two-dose category, 147 of 846 in the three-dose category, and 0 of 7 in the not-treated category. These figures refer to participants affected, not necessarily the total number of event episodes. No overall count for the primary endpoint is reported in the registry record, so the other-event counts should not be treated as that overall endpoint result.

Six serious-event terms are listed with a reported percentage of 1.4% each: biliary dilatation, acute cholecystitis, device-related infection, jaw fracture, rib fracture, and road traffic accident. The registry record does not report the corresponding term-specific counts or denominators in the information summarized for this analysis. The terms and percentages do not, on their own, establish causation. The adverse-event definition does not require a causal link, and investigators assess relatedness to study drug.

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

The results describe adverse events recorded during an open-label study of AGN-151586. The registry identifies the primary safety endpoint, its timeframe, and the safety population. It also reports serious and other adverse-event counts across categories defined by dose received, along with deaths and selected serious-event terms. This is useful descriptive information about events observed in the study record.

The posted data do not establish that AGN-151586 caused any particular event. The adverse-event definition expressly includes events without a necessary causal relationship, while investigators assess relatedness. The overall numerical result for the primary endpoint is not reported in the registry record. The listed dose-category counts therefore do not fill that gap or provide a comprehensive overall primary endpoint result.

The counts also do not show that a particular dose category is safer or less safe than another. Participants were not randomized among the dose categories, and additional treatment depended on meeting retreatment criteria. Participants in different categories may have differed in relevant ways; an unadjusted contrast would not address those differences. The registry warns that these categories are not a like-for-like control comparison. The not-treated category is not a randomized control group.

No inferential analysis, confidence interval, p-value, or adjusted comparison is reported for these safety counts. Their precision and the uncertainty around any comparative effect therefore cannot be assessed from the registry summaries. In general, descriptive event counts can indicate what was recorded but cannot alone distinguish a treatment effect from background events or other explanations.

The record also does not establish efficacy for improving glabellar lines through the primary safety endpoint. The study’s stated primary purpose is safety, and the information summarized for this analysis does not provide an efficacy result. Conclusions should remain limited to the registry’s descriptions and counts, without converting them into a treatment recommendation or a definitive causal claim.

14. Why This Trial Matters Statistically

This trial illustrates why statistical interpretation begins with design rather than with a comparison of numbers. A completed Phase 3 study and a large enrollment do not automatically create a randomized treatment contrast. This study is open-label and single-group, with dose categories shaped by retreatment criteria. Its event counts can describe what was observed, but they cannot be interpreted as a randomized dose-response comparison.

It also shows the importance of distinguishing endpoints. The primary endpoint counts participants with adverse events over a defined follow-up period. Serious-event counts and other adverse-event counts are related safety descriptions, but they are not interchangeable with the overall primary endpoint. Because the primary numerical result is not reported in the registry record, readers should not use the subgroup summaries as a proxy for that missing result.

Denominators and population definitions matter as much as numerators. The safety population is defined by receipt of at least one dose, while the adverse-event summaries are displayed across dose categories and a not-treated category. Without an explicit, complete account of how those categories relate to each analysis population, summing them or treating them as mutually comparable would be inappropriate.

Finally, the record demonstrates the boundary between descriptive safety surveillance and causal inference. Event occurrence, investigator assessment of relatedness, and a causal treatment effect are different concepts. Transparent interpretation requires keeping those distinctions visible, especially when no comparative analysis, uncertainty estimate, or missing-data approach is reported.

15. 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 main limitation for statistical interpretation is the absence of a randomized control group. The study is single-group, open-label, and unmasked. The dose categories reflect treatment received and retreatment criteria, rather than random assignment. Their counts cannot support an unadjusted causal comparison between dose levels or against the not-treated category.

The primary endpoint’s numerical result is not reported in the registry record, even though its definition and timeframe are stated. The separate serious and other adverse-event counts do not replace the missing overall count of participants with any adverse event. The record lists selected serious-event terms with percentages but does not report their term-specific counts or denominators in the information.

The registry does not report confidence intervals, p-values, adjusted estimates, a statistical analysis plan, multiplicity procedures, missing-data methods, or sensitivity analyses. It also does not provide details needed to assess completeness of follow-up or the handling of incomplete event information. These limitations prevent assessment of precision and analytic robustness beyond the descriptive figures.

Although the registry lists enrollment as 992 and identifies a safety population of n=985, the record does not give a full accounting of population flow in the information summarized for this analysis. The listed categories should not be combined to infer additional totals. The sample-size assumptions described for planning illustrations are not the trial’s design justification and do not establish observed power. Taken together, these constraints support a narrow reading of the posted information as descriptive safety reporting rather than a definitive estimate of treatment effect.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: A Study to Assess Adverse Events of Intramuscular AGN-151586 Injection in Adult Participants With Glabellar Lines — NCT05248893.
• Registry record last updated 2026-09-25; status last verified 2026-09.
• Results first posted 2026-09-25.
• 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.

19. Record Summary

NCT05248893 is a completed Phase 3, multicenter, open-label, single-group study sponsored by AbbVie. It evaluated intramuscular AGN-151586 for adults with glabellar lines. The registry lists enrollment as 992 and the safety population as participants receiving at least one dose, n=985. Participants received 5 injections on Day 1, with up to 2 additional doses possible for those meeting retreatment criteria.

The primary endpoint counts participants with adverse events from Day 1 (Baseline) to Day 126. Its numerical overall result is not reported in the registry record. Dose-category summaries report serious and other adverse-event counts, and 0 deaths in each listed category. These are descriptive findings from a nonrandomized study, not like-for-like treatment comparisons. The record lists 7 outcome measures and 0 analyses; inferential results, missing-data methods, and a detailed statistical plan are not reported in the registry record.