A Study to Evaluate How Ontamalimab Works and Assess Its Safety and Tolerability in People With Nonalcoholic Steatohepatitis With Fibrosis Stages 1 to 4: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study to Evaluate How Ontamalimab Works and Assess Its Safety and Tolerability in People With Nonalcoholic Steatohepatitis With Fibrosis Stages 1 to 4 (NCT07052682), a na phase 1 study. The primary outcome is Number of Participants With Treatment-emergent Adverse Events (TEAEs).

2. Clinical Question

The central question is therefore about safety and tolerability during and after ontamalimab exposure in this study population, rather than whether the drug performed better than another treatment or a control. A single-arm design can describe events observed among treated participants, but it cannot separate effects of treatment from events that might occur because of the underlying condition, other factors, or chance.

The record also identifies biomarker outcomes, including changes in Pro-C3, Enhanced Liver Fibrosis, and liver iron-corrected T1 mapping by magnetic resonance imaging. These measures relate to the study’s interest in liver scarring and inflammation. However, outcome names alone do not establish what changes occurred, how variable they were, or whether they were judged clinically meaningful. The registry record does not report analyses for these outcomes.

3. Trial Design

This was a multicenter, single-arm, open-label Phase 1b study of ontamalimab in participants with steatohepatitis and fibrosis stage 1 through 4. The record lists the study as Phase 1 and describes the study as Phase 1b in its official title. It was not randomized, and there was no masking. The enrollment was 11.

All participants were assigned to the ontamalimab group; the study did not include a separate control group. Participants received a 75 milligrams subcutaneous injection once every 4 weeks. The record describes the first dose on Day 1, a last dose at Week 20, and a total treatment period of 24 weeks. Overall participation was described as approximately up to 46 weeks.

The study’s primary outcome was the number of participants with treatment-emergent adverse events, assessed from the first dose up to Week 36. The record defines a treatment-emergent event as one that appeared or manifested at or after treatment began, or an existing event that worsened in intensity or frequency after exposure. An adverse event did not need to be considered caused by the study drug to meet the definition.

Secondary outcomes were changes from baseline in Pro-C3 and Enhanced Liver Fibrosis through Week 24, and change from baseline in liver iron-corrected T1 mapping by magnetic resonance imaging at Week 24. The record lists eight outcome measures overall, but the number of analyses is zero. Results for the named biomarker outcomes are not reported in the registry record.

The study status is terminated. The start date was 2023-01-18, and the primary completion date was 2024-12-30. The reason for termination and any consequences for the planned study procedures are not reported in the registry record. With no comparator, the design is primarily descriptive: it can report events among participants who received treatment, but it does not provide a direct treatment-versus-control estimate.

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 11 participants were enrolled and received study treatment. The study was terminated early by the sponsor due to a strategic shift and reprioritization of clinical programs within Takeda.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: The safety analysis set consisted of all participants who were enrolled in the study and had received at least 1 dose of study drug.

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: The safety analysis set consisted of all participants who were enrolled in the study and had received at least 1 dose of study drug.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With Treatment-emergent Adverse Events (TEAEs), measured over From first dose of study drug up to Week 36.

The primary endpoint is the number of participants with treatment-emergent adverse events from the first dose of study drug up to Week 36. It is a count of participants who experienced an event, not a measure of how many total events occurred or how severe each event was.

The registry’s definition includes events that began after treatment started and existing events that worsened in intensity or frequency following exposure. Importantly, an adverse event does not have to be judged related to treatment to be counted. The endpoint therefore describes events arising during the specified observation period; by itself, it does not establish their cause.

General statistical context: safety outcomes are commonly used to characterize the types and frequency of medical events observed during a study. A participant-based count makes clear how many people experienced at least one qualifying event, while separate summaries may distinguish serious events or other event categories. Interpretation depends on the definition, follow-up period, and number of participants observed.

The posted registry record does not report the primary endpoint result or an analysis of it. The adverse-event summary separately lists counts for serious events, other events, and deaths. Those figures offer limited descriptive safety information, but they do not substitute for a reported primary-endpoint analysis or establish whether any event was caused by ontamalimab.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

General statistical context: a clinical outcome has to be defined before its results can be interpreted. The definition specifies what is counted, which participants are included, and the period during which events are observed. In this study, the primary outcome is a participant count for treatment-emergent adverse events, with observation from the first dose up to Week 36. The registry record also defines what qualifies as treatment-emergent and clarifies that an event need not be attributed to the drug.

What does a participant count describe?

A count of participants with an event answers how many people experienced at least one qualifying event. It differs from a count of all event episodes: a participant with multiple events may still contribute once to a participant-based measure. The primary outcome’s title identifies a participant count, but its numerical result is not reported in the registry record. The separate safety summary gives counts for serious events, other events, and deaths; these should be read according to their labels rather than assumed to be interchangeable with the primary outcome.

General statistical context: counts are most informative when read with their denominator, outcome definition, and follow-up period. The denominator indicates how many participants were at risk of having an event recorded. Follow-up defines how long an event could be observed. Differences in either the denominator or observation time can affect comparisons, which is one reason a clear outcome definition matters. Here, the safety summary lists 11 participants at risk for serious events and 11 at risk for other events, while the primary endpoint specifies observation up to Week 36.

What can an open-label, single-arm study estimate?

General statistical context: a single-arm study describes outcomes in one treated group. Without a concurrent control group, it does not estimate a direct difference between treatment and control. An open-label design means masking was absent, as the registry record states; the record does not describe additional procedures to reduce awareness of treatment assignment. For an outcome based on reported or assessed events, design features can be relevant to how events are noticed, attributed, or recorded. The registry record does not report further assessment procedures.

In a comparative trial, an effect estimate usually contrasts outcomes across groups under a specified analysis plan. No such group contrast is available because there was only one treatment group. The posted counts therefore describe events recorded in that group and do not identify what would have happened to the same participants under a different treatment or without treatment.

How should precision be understood?

General statistical context: an estimate is more useful when its uncertainty is also described. A confidence interval is a range of values compatible with the observed data under a stated statistical method; it conveys uncertainty rather than guaranteeing that the true value lies within that particular interval. A small number of observed participants can leave substantial uncertainty, even when a count appears straightforward. The registry record does not report a confidence interval for the primary endpoint or for the adverse-event counts.

General statistical context: methods for event counts may need to account for variation in the number of events across participants. Over-dispersion means that the observed variability is greater than a model assumes; if present and ignored, standard errors and confidence intervals can be misleading. This concept is relevant to analyses of event counts in general, but the registry record does not report an event-count model, an over-dispersion assessment, or an inferential analysis for this study. It would therefore be inappropriate to attribute any such method to the trial.

What does the registry say about the analysis?

The record lists eight outcome measures and zero analyses. The primary endpoint’s result, its uncertainty, and a detailed statistical analysis plan are not reported in the registry record. The record also does not report a sample-size justification, interim analyses, or a plan for handling missing observations. These omissions mean that readers cannot evaluate whether the analysis followed a prespecified plan, whether the available participants represent the planned analysis population, or how incomplete outcome data were handled.

The safety analysis set is described as participants who were enrolled and received at least one dose. The summary lists 11 participants at risk in each of the serious-event and other-event categories. General statistical context: an analysis population defines which participants contribute to a particular result, and different endpoints can have different analysis populations. The definition given for the safety set does not itself establish that every planned endpoint used the same population.

The record also names secondary biomarker outcomes. General statistical context: a change-from-baseline outcome compares a follow-up measurement with a participant’s starting measurement, and interpretation depends on the measurement scale, timing, available data, and analysis method. The registry record names the outcomes and assessment time points but does not report their results or analysis details. No conclusion about biomarker change or its precision can be drawn from the outcome names alone.

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("Ontamalimab")
n      <- c(11)
events <- c(6)
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  Ontamalimab  11  6  54.5  23.4  83.3  28.0  78.7  27.7  78.9

11. Multiplicity, Missing Data and Analysis Populations

The registry record names a primary safety outcome and secondary biomarker outcomes, but does not report a detailed statistical analysis plan or any analyses. It is therefore not reported in the registry record whether the study used a formal approach to multiplicity, such as prioritizing tests or adjusting interpretation when multiple outcomes are examined.

General statistical context: when several outcomes are tested, the chance of obtaining an apparently notable result by chance can increase if each is assessed independently. A prespecified strategy can clarify which results are confirmatory and how other findings should be interpreted. Without a reported strategy and without outcome analyses, there is no basis for describing a multiplicity adjustment or the inferential status of any biomarker result.

Missing-data procedures are also not reported in the registry record. The outcome descriptions do not establish whether every participant had an assessment at each planned time point, how incomplete observations were handled, or whether any participants discontinued before follow-up ended. The study’s terminated status does not, by itself, establish that data were missing or explain why the study ended.

The safety analysis set is defined as enrolled participants who received at least one dose. The adverse-event summary lists 11 participants at risk in both event categories. The record does not give a separate participant flow or outcome-specific analysis populations for the biomarker measures. General statistical context: knowing which participants contributed to each analysis is important because the analyzed group may differ from the enrolled group when data are incomplete or unavailable. In the absence of those details and of reported analyses, the extent and handling of missing data cannot be assessed.

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 non-serious adverse event terms

The adverse-event summary lists 0 participants with serious adverse events among 11 participants at risk, 6 participants with other adverse events among 11 at risk, and 0 deaths. These figures are descriptive counts in the ontamalimab group. The registry record does not list serious adverse-event terms.

General statistical context: a zero count means no event in that category was recorded among the participants at risk during the relevant observation. It does not establish that the event is impossible or that the treatment has no associated risk. With a limited number of participants, rare or less frequent events may not appear in a study even when they could occur in a larger population or with longer observation.

The counts also do not establish causality. The registry defines adverse events without requiring a causal relationship to the study drug. The record does not report additional details about event severity, timing, duration, outcome, or attribution for the listed other events. These safety figures should therefore be read as event counts observed in the study, not as a complete characterization of risk or as a comparison against another treatment.

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

The posted record establishes the basic design and provides limited adverse-event counts for an open-label, single-arm study of ontamalimab. It reports 0 serious events among 11 participants at risk, 6 participants with other adverse events among 11 at risk, and 0 deaths. These values describe the participants represented in the safety summary; they do not establish a comparative treatment effect.

The primary endpoint was the number of participants with treatment-emergent adverse events through Week 36. Its result is not reported in the registry record. Nor are analyses reported for the named secondary outcomes: changes in Pro-C3 and Enhanced Liver Fibrosis through Week 24, and change in liver iron-corrected T1 mapping by magnetic resonance imaging at Week 24. No direction, magnitude, or precision of biomarker change can be inferred from their inclusion as outcomes.

General statistical context: a single-arm observation can describe what was recorded during treatment and follow-up, but cannot determine how those outcomes compare with an alternative. Events can occur for reasons other than treatment, and the registry’s adverse-event definition does not require a causal relationship. A lack of recorded serious events in this group is not evidence that serious events cannot occur.

The study was terminated, but the reason is not reported in the registry record. The record does not explain whether termination changed the planned follow-up, reduced the availability of results, or reflected a safety finding. No such explanation should be inferred from status alone.

Accordingly, the record supports a description of the intervention schedule, the planned outcomes, and the reported safety counts. It does not support a conclusion about comparative safety, treatment efficacy, biomarker response, or the cause of any event. The absence of posted analyses leaves uncertainty about the primary outcome and the secondary measures.

14. Why This Trial Matters Statistically

This study is statistically notable for the gap between its clearly defined questions and the limited results reported in the registry record. It describes a safety-focused primary endpoint, specifies an observation period, and names secondary biomarker outcomes. Yet it lists zero analyses, and the primary-endpoint result and biomarker findings are not reported. Readers can identify what the study set out to measure, but cannot evaluate those planned results from this record.

The single-arm design also matters for interpretation. A treated group can be described, but the absence of a comparator prevents a direct estimate of how outcomes differ from another treatment or from no study treatment. This remains true even when event counts are available. The safety summary’s counts are informative as a description of the recorded participants, not as evidence of a relative treatment effect.

General statistical context: reporting the analysis population, outcome definitions, follow-up, uncertainty, and handling of missing data helps readers judge how much weight to place on a result. Those details are particularly important when enrollment is limited, because estimates can be imprecise and may not capture uncommon events. The record does define the safety analysis set and the primary endpoint’s event criteria, but it does not report confidence intervals, a detailed analysis plan, or missing-data procedures.

The listed biomarker outcomes show that the study was interested in more than adverse events. However, without reported values and analyses, the outcomes cannot be used to characterize biomarker trajectories or their variability. Likewise, termination is an important record status, but its statistical implications cannot be determined without the reason and information about data completion.

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 principal limitation is that the registry record does not report a primary-endpoint result or any analysis, despite defining the number of participants with treatment-emergent adverse events as the primary outcome. The named secondary biomarker outcomes also have no reported results. This prevents assessment of the measured changes, their precision, or how many participants contributed to those analyses.

The study enrolled 11 participants and used a single-arm, open-label design without randomization or masking. There is no concurrent control group, so the record cannot support a direct comparative estimate. The event counts are descriptive and do not establish whether events were caused by ontamalimab. The registry also does not report confidence intervals or other measures of uncertainty for the safety counts.

The study status is terminated, but the reason is not reported in the registry record. Nor does the record report whether planned follow-up was completed for every participant, how missing observations were handled, or whether termination affected outcome availability. The safety analysis set is defined, but outcome-specific analysis populations for the biomarker measures are not reported.

Further limitations include the absence of a reported detailed statistical plan, sample-size justification, multiplicity approach, and interim-analysis information. These items are not reported in the registry record; their absence from the record does not establish what procedures were or were not conducted. The study’s limited posted results make it important to distinguish documented safety counts from outcomes that remain unreported.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: A Study to Evaluate How Ontamalimab Works and Assess Its Safety and Tolerability in People With Nonalcoholic Steatohepatitis With Fibrosis Stages 1 to 4 — NCT07052682.
• Registry record last updated 2025-08-19; status last verified 2025-08.
• Results first posted 2025-08-19.
• 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

This registry record describes a multicenter, open-label, single-arm Phase 1b study of ontamalimab in participants with nonalcoholic steatohepatitis or metabolic dysfunction-associated steatohepatitis and liver fibrosis stage 1 through 4. The record lists 11 enrolled participants and identifies Takeda as the sponsor.

Participants received ontamalimab 75 milligrams by subcutaneous injection once every 4 weeks. The record describes dosing from Day 1, a last dose at Week 20, and a total treatment period of 24 weeks. The primary outcome was participants with treatment-emergent adverse events through Week 36. Secondary outcomes included changes in Pro-C3, Enhanced Liver Fibrosis, and liver iron-corrected T1 mapping.

The study is listed as terminated. The safety summary reports 0 serious adverse events among 11 at risk, 6 participants with other adverse events among 11 at risk, and 0 deaths. The primary-endpoint result, biomarker analyses, and reason for termination are not reported in the registry record.