Induction Study #1 of Oral Ozanimod as Induction Therapy for Moderately to Severely Active Crohn's Disease: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Induction Study #1 of Oral Ozanimod as Induction Therapy for Moderately to Severely Active Crohn's Disease (NCT03440372), a randomized phase 3 study. The primary outcome is Percent of Participants With a Crohn's Disease Activity Index (CDAI) Score < 150 at Week 12.

2. Clinical Question

The study was designed to examine ozanimod as induction treatment, with the primary outcome focused on a CDAI threshold at Week 12. CDAI combines information about stool frequency, abdominal pain, general well-being, complications, use of antidiarrheal drugs, abdominal mass, hematocrit, and body-weight change. Its score reflects clinical activity, with higher scores indicating worse disease. A result below 150 is the threshold used for the primary endpoint; the endpoint is a percentage, not a mean CDAI score or change from baseline.

The registry also lists secondary outcomes involving abdominal pain and stool frequency, endoscopic assessment, CDAI improvement, combinations of clinical and endoscopic criteria, and histologic activity. These outcomes represent different aspects of disease activity and are not interchangeable. The registry record does not report their results. Without the outcome data, the stated question can be described, but the relative outcome observed with ozanimod and placebo cannot be assessed from this record.

3. Trial Design

This is a phase 3, multicenter, randomized, double-blind, placebo-controlled, parallel-group study. The listed interventions are oral ozanimod and placebo. The registry describes masking as quadruple, but does not identify which participant, care, assessment, or analysis roles were masked. It does not give details of the randomization procedure, allocation ratio, treatment duration beyond the induction context, or the exact dosing schedule in the arm descriptions.

The registry records enrollment of 625 participants. Enrollment is not, by itself, a report of how many participants were included in each outcome analysis. The primary outcome description specifies an intended-to-treat population consisting of randomized participants who received at least one dose of investigational drug. Group-specific analysis denominators for the primary outcome are not reported in the registry record.

The study began on 2018-02-27, has a listed primary completion date of 2024-10-01, and is marked terminated. The registry record does not explain the reason for termination or describe whether the planned follow-up and analyses were completed. These administrative details matter when interpreting the absence of posted efficacy results: termination status alone does not establish what happened to the study or why results are unavailable.

Ozanimod and placebo are identifiable as interventions, but the safety groups are labeled Treatment 1 and Treatment 2. Their mapping to the named interventions is not reported in the registry record. As a result, the serious and other adverse-event counts can be described by their registry group labels, but should not be assigned to ozanimod or placebo based on these data alone.

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 625 participants were randomized and of these 623 received at least one dose of study treatment.

Pre-Treatment

Treatment

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Intent to treat population consist of all randomized participants that received at least 1 dose of investigational 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.

6. Primary Endpoint

The registry lists the primary outcome as Percent of Participants With a Crohn's Disease Activity Index (CDAI) Score < 150 at Week 12, measured over At Week 12.

The primary endpoint is the percentage of participants with a CDAI score below 150 at Week 12. CDAI is a composite measure of Crohn’s disease activity. It incorporates reported symptoms, including stool frequency, abdominal pain, and general well-being, alongside clinical information such as complications, abdominal mass, hematocrit, and body-weight change. Symptom scores are based on the seven days before a visit, while the other factors contribute to the total score.

The registry describes CDAI scores as ranging from 0 to 600, with higher values indicating worse disease. It characterizes scores from 150 to 219 as mild, from 220 to 450 as moderate, and above 450 as severe. The primary endpoint uses a threshold rather than the full score: participants are counted according to whether their Week 12 score is below 150. It therefore asks about the proportion reaching that criterion, not the average severity of disease across the group or the size of individual score changes.

A threshold-based endpoint can make a clinical response criterion easier to interpret, but it also compresses a range of scores into a yes-or-no outcome. A score just below the threshold and a much lower score both meet the endpoint, while a score just above it does not. The registry record does not report the percentages, denominators, uncertainty estimates, or comparison for this outcome, so its observed result and precision cannot be described.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does randomization contribute?

In general, randomization assigns participants to treatment groups using a chance-based process. Its purpose is to make treatment assignment independent of participant characteristics on average, reducing the risk that systematic baseline differences explain a later group contrast. Randomization does not guarantee that groups are identical in every respect, and it does not remove uncertainty from finite data. The registry identifies the study as randomized but does not report the sequence-generation method, allocation concealment details, or any assessment of baseline balance.

What does masking mean?

In general, masking is intended to limit the influence of treatment knowledge on participant reports, clinical care, outcome assessment, or analysis. This is especially relevant when an outcome includes symptom reports, because expectations can affect reporting and interpretation. The registry labels this study quadruple-masked, but does not specify the roles covered by that label or how masking was maintained. The record therefore establishes the stated masking level, not the operational details or success of masking.

How should a binary percentage outcome be understood?

The primary endpoint is a binary outcome summarized as a percentage: each participant either meets the CDAI threshold at Week 12 or does not. A group percentage describes the observed proportion meeting the criterion among the participants included in that analysis. Comparing group percentages can describe an absolute difference in outcome proportions, but the registry record does not report the underlying percentages or a comparison estimate. No such comparison can be reconstructed from the enrollment total alone.

General statistical uncertainty applies to percentages as well as to continuous measurements. A confidence interval gives a range of values compatible with the observed data under the specified statistical method. It helps distinguish a precise estimate from one with substantial uncertainty. The registry record does not report a confidence interval or another uncertainty measure for the primary outcome. It also does not state the primary analysis model, covariate adjustments, or handling of repeated or missing measurements.

Why do analysis populations matter?

An analysis population defines which participants contribute to an outcome estimate. The primary outcome description states that the intended-to-treat population consists of randomized participants who received at least one dose of investigational drug. That definition should be read as the registry’s stated population, rather than assuming that all enrolled participants were included in every analysis. The record does not give the group-specific denominators, numbers excluded, or reasons for exclusion. It also does not explain how participants without an observed Week 12 assessment were handled.

In general, missing outcome data can affect interpretation when the likelihood of missingness is related to participants’ health, treatment, or outcomes. Different approaches to missing data rely on different assumptions and can yield different estimates. The registry record does not report a missing-data strategy, sensitivity analyses, or the amount and pattern of missing outcome information. The impact of missingness on the primary comparison therefore cannot be assessed.

What is the role of statistical testing?

General hypothesis testing evaluates data against a specified null hypothesis using a statistical model and a chosen significance threshold. A p-value describes how unusual the observed data, or data more extreme, would be under that null hypothesis and model; it is not the probability that a treatment effect is true. A p-value alone also does not convey the size or clinical importance of an estimate. The registry record does not report a primary-outcome p-value, significance threshold for the primary analysis, or test specification.

The sample-size assumptions describe a planning illustration based on an observed effect, a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. Such an illustration is a conditional planning calculation, not observed power and not evidence that the trial was designed around those assumptions. The registry record does not report the trial’s own sample-size justification or establish that these illustration assumptions were used in the protocol. No calculated planning values are reported in the registry record.

Why does multiplicity matter?

When a study evaluates multiple outcomes or makes multiple statistical comparisons, the chance of at least one apparently notable finding can increase if each is interpreted separately. General methods for addressing multiplicity can include a prespecified testing sequence, adjusted significance thresholds, or a clear distinction between confirmatory and exploratory analyses. The registry lists numerous secondary outcomes, but does not report a multiplicity strategy, endpoint hierarchy, or statistical analysis plan. The presence of multiple outcomes alone does not establish which were confirmatory or how inference was controlled.

The registry identifies the trial as parallel-group and placebo-controlled, but it does not provide enough information to reproduce a statistical analysis. The outcome definitions and some population details are recorded, while the primary estimates, uncertainty, model specifications, missing-data procedures, and multiplicity plan are not. Statistical interpretation should therefore remain at the level of the registered question and descriptive safety counts rather than implying an unreported treatment effect.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary outcome and numerous secondary outcomes, including symptom-based, CDAI-based, endoscopic, combined clinical-endoscopic, and histologic measures. Evaluating several outcomes creates a multiplicity issue in general: if each comparison is treated as an independent confirmatory test, the chance of at least one apparently positive result can rise. Prespecified testing sequences or other multiplicity procedures can help define how evidence across outcomes should be interpreted. The registry record does not report whether such a procedure was planned, how outcomes were prioritized, or which secondary outcomes were intended as confirmatory.

The registry record also does not report a statistical analysis plan. Details not reported include the primary comparison method, covariate adjustment, missing-data approach, sensitivity analyses, and any interim analyses. The absence of this information does not establish that no such procedures existed; it means they cannot be characterized from the registry record.

The primary outcome description defines the intended-to-treat population as randomized participants who received at least one dose of investigational drug. Group-specific denominators, participant flow through the study, exclusions from analysis, and the number with missing Week 12 outcomes are not reported in the registry record. Without those details, it is not possible to assess whether the endpoint analysis included the stated population or how missing observations may have affected the estimates.

General methods for missing data depend on assumptions about why observations are unavailable. Sensitivity analyses can examine how conclusions change under alternative assumptions, but the record does not report whether any were conducted. The result is a substantial limit on assessing the robustness of any primary or secondary outcome estimate, which itself is not reported.

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 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: crohn's disease (2.4%), subileus (0.5%), abdominal abscess (0.5%), pneumonia aspiration (0.5%), incision site haemorrhage (0.5%).

The registry reports adverse events using the labels Treatment 1 and Treatment 2. For Treatment 1, 416 participants were listed as at risk for serious adverse events and 27 were listed as affected; 416 were listed as at risk for other adverse events and 22 as affected. For Treatment 2, 207 were listed as at risk for serious adverse events and 10 as affected; 207 were listed as at risk for other adverse events and 22 as affected. No deaths were reported in either group.

The treatment-group mapping is not reported in the registry record, so these figures should not be attributed to ozanimod or placebo. The counts are descriptive: the record does not provide event timing, exposure duration, recurrent-event counts, or an adjusted comparison. It also does not report whether the categories represent participants with at least one event or how events were defined beyond the serious and other labels.

The listed serious-event terms include Crohn’s disease at 2.4%, and Subileus, Abdominal abscess, Pneumonia aspiration, Incision site haemorrhage, and Skin laceration at 0.5% each. The registry excerpt does not provide treatment-group attribution for these terms. These entries describe reported events; they do not, by themselves, establish that an intervention caused an event or permit a comparative safety conclusion.

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

The record establishes that this was a randomized, double-blind, placebo-controlled phase 3 study of oral ozanimod for moderately to severely active Crohn’s disease, with a primary endpoint based on CDAI status at Week 12. It also records enrollment of 625 participants and a terminated status. These registry entries describe the trial’s registered structure and administrative status, but they do not give the primary efficacy result.

The central limitation is that the registry record does not report the Week 12 percentage meeting the primary CDAI threshold in either group, a treatment contrast, or an uncertainty interval. It therefore does not show the direction or magnitude of the primary comparison, nor how precisely that comparison was estimated. The listed secondary outcomes cannot fill this gap because their results are also not reported.

Termination should not be read as a result. The registry does not state why the study was terminated or whether termination followed a data review, operational issue, safety concern, or another circumstance. No explanation should be inferred from the status alone. Similarly, the absence of posted outcome values in this record does not establish that no analyses were conducted or that results were absent elsewhere.

The safety entries give counts under treatment labels whose mapping to the named interventions is not reported. They offer descriptive information about recorded adverse events, but do not support attribution to ozanimod or placebo or a comparative safety assessment. No deaths are reported in either group, but this fact does not replace the broader safety information that would be needed to characterize event types, timing, exposure, and uncertainty.

In general, a treatment-effect conclusion requires an estimate interpreted alongside its uncertainty, analysis population, outcome handling, and prespecified statistical plan. Those elements are not available for the primary result in the registry record. The appropriate interpretation is therefore limited: the trial’s question and design are documented, while its posted efficacy findings and explanation for termination are not reported.

13. Why This Trial Matters Statistically

This trial is statistically notable as a registered phase 3 randomized comparison of an induction treatment with placebo for moderately to severely active Crohn’s disease. Its primary outcome uses a clinically interpretable CDAI threshold at Week 12, while its secondary outcomes span symptoms, endoscopic findings, combinations of clinical and endoscopic criteria, and histologic activity. The range of measures illustrates why endpoint definitions and a prespecified analysis strategy matter: different outcomes represent distinct aspects of disease activity and should not be treated as equivalent evidence.

The record also demonstrates the distinction between a registered study design and an interpretable results record. Randomization, masking, comparator choice, and the stated analysis population give useful context, but do not establish an effect without group outcomes and a comparison estimate. A sample-size illustration based on observed effects is a planning aid, not observed power, and cannot supply missing outcome evidence.

Multiplicity and missing-data methods are consequential when there are multiple endpoints and an outcome assessed at a specified follow-up visit. Yet the registry does not describe an endpoint hierarchy, multiplicity procedure, missing-data strategy, or statistical analysis plan. The primary results are not reported, so readers cannot assess the effect estimate, its precision, or the robustness of the analysis.

The terminated status and the unexplained absence of posted primary results are important limitations for interpretation, but they do not reveal a cause or outcome. The statistical lesson is to distinguish what the record establishes—the design and registered questions—from what it leaves unresolved, including efficacy, precision, analysis conduct, and the reason for termination.

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 most direct limitation is the absence of reported primary outcome results. The registry record does not provide Week 12 group percentages, analysis denominators, a between-group estimate, or an uncertainty measure. The secondary outcomes are listed without results, so they cannot provide corroborating or contrasting evidence about clinical, endoscopic, or histologic activity.

The status is terminated, but the reason and circumstances are not reported in the registry record. The listed primary completion date does not explain the termination or establish that all planned assessments and analyses were completed. The arm descriptions are also blank, leaving dosing and administration details unspecified in this record. Although the study is described as quadruple-masked, the identities of the masked roles and the procedures used to preserve masking are not reported.

The primary outcome description provides a definition of the intended-to-treat population, but the record does not report participant flow, group-specific outcome denominators, missingness, or exclusions. It also does not state how missing Week 12 values were handled. These omissions prevent evaluation of whether the analysis population and missing-data assumptions could influence an outcome estimate.

The registry lists multiple secondary endpoints but does not report the statistical analysis plan, multiplicity handling, interim analyses, model specifications, or the trial’s sample-size justification. Safety data use Treatment 1 and Treatment 2 labels that are not mapped to the named interventions. Event timing and exposure information are not reported. These are limitations of what can be interpreted from this registry record; they do not establish that the details or analyses were absent from other study materials.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Induction Study #1 of Oral Ozanimod as Induction Therapy for Moderately to Severely Active Crohn's Disease — NCT03440372.
• Registry record last updated 2025-11-04; status last verified 2025-10.
• Results first posted 2025-11-04.
• 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

NCT03440372 is a phase 3, multicenter, randomized, double-blind, placebo-controlled, parallel-group study of oral ozanimod as induction therapy for moderately to severely active Crohn’s disease. The registry records enrollment of 625 participants and lists a primary endpoint of the percentage with a CDAI score below 150 at Week 12. The stated primary analysis population consists of randomized participants who received at least one dose of investigational drug.

The record lists symptom, endoscopic, combined clinical-endoscopic, and histologic secondary outcomes. It is marked terminated, with a primary completion date of 2024-10-01; the reason for termination is not reported in the registry record. Primary and secondary outcome results are not reported. Safety counts are listed under Treatment 1 and Treatment 2, without a mapping to ozanimod and placebo. Thus, the registry documents the trial design and questions, but does not support an interpretation of the primary treatment effect.