A Study to Learn About the Study Medicine Etrasimod in Adults With Moderate to Severe Atopic Dermatitis (AD) Who Have Already Tried Treatments Taken by Mouth or by Injection: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study to Learn About the Study Medicine Etrasimod in Adults With Moderate to Severe Atopic Dermatitis (AD) Who Have Already Tried Treatments Taken by Mouth or by Injection (NCT05732454), a randomized phase 2, phase 3 study. The primary outcome is Part 1, DB Period: Percentage of Participants Achieving Investigator's Global Assessment (IGA) Response at Week 16.

2. Clinical Question

3. Trial Design

The registry record describes a randomized, quadruple-masked, parallel-group Phase 2/3 study of oral etrasimod for adults with moderate-to-severe atopic dermatitis and a history of prior systemic treatment failure. The record lists an enrollment of 58 and a status of terminated. It does not report the reason for termination.

The study had two parts. In Part 1, participants were assigned to etrasimod 2 mg once daily or oral placebo for a 16-week double-blind period. The primary endpoint and the two posted secondary outcomes concern this period, with results assessed at Week 16. The registry summary says that some participants could continue after the initial period for an additional 52 weeks, knowing that they were taking etrasimod. The registry record does not report the criteria for continuing or how many participants continued.

The posted primary outcome groups include 30 participants assigned to etrasimod and 28 assigned to placebo. The primary population is described as the FAS, which included all randomized participants irrespective of whether they received any study intervention dose; participants were analyzed as randomized. The primary endpoint description also refers to the number of FAS participants with baseline IGA at least 2. The full details of that population statement are not reported in the registry record.

Randomization is intended to make treatment groups comparable on average, while masking can reduce the influence of treatment knowledge on care, reporting, and assessment. These are general features of trial design; they do not guarantee balance or eliminate bias in a particular trial. The registry record does not report the randomization sequence or allocation concealment details. It also does not report the trial's original sample-size assumptions or the reason the study was terminated.

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 58 participants with moderate-to-severe atopic dermatitis (AD) were enrolled in Part 1- DB period and out of them 51 continued into the Part 1- OLE period.

Part 1: DB Period

Reasons for not completing this period:

Part 1: OLE Period

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: FAS included all participants who were randomized to the study irrespective of whether they received any dose of study intervention (i.e., etrasimod or placebo). Participants were analyzed in the treatment groups as they were randomized. Number of participants in FAS with baseline IGA\>=2 was included in this analysis.

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 full analysis set (FAS) included all participants who were randomized to the study irrespective of whether they received any dose of study intervention (i.e., Etrasimod or placebo). Participants were analyzed in the treatment groups as they were randomized.

6. Primary Endpoint

The registry lists the primary outcome as Part 1, DB Period: Percentage of Participants Achieving Investigator's Global Assessment (IGA) Response at Week 16, measured over DB Period: Week 16.

The primary endpoint is the percentage of participants achieving an Investigator's Global Assessment response at Week 16 in the double-blind period. The IGA measures atopic dermatitis severity on a scale from 0, clear, to 4, severe. A response required a score of 0 or 1, corresponding to clear or almost clear, together with a reduction of at least 2 points from baseline.

This definition combines an end-of-period disease-severity threshold with improvement from the participant's starting score. In general, requiring both conditions distinguishes reaching a specified state from simply having some improvement; a participant must meet the final severity criterion and the change criterion. The registry record identifies the endpoint as a percentage of participants, so the result is a binary outcome at the participant level: each participant either meets the response definition or does not.

An IGA response is useful for comparing the proportion reaching a clinically described severity category under each assigned treatment. It is not a complete description of every aspect of atopic dermatitis or every participant's course. The endpoint concerns the Week 16 assessment in the double-blind period, and should be interpreted as a measure of that defined response at that time. Other measures, including EASI outcomes, are listed separately as secondary outcomes.

7. Results Posted in the Registry

• DB Period: Etrasimod 2 mg: 3.3% (1/30) versus 7.1% (2/28) on control; risk difference -3.8 percentage points (95% CI -15.3 to 7.7), risk ratio 0.47 (0.04–4.87); unadjusted two-proportion z-test p = 0.513.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Part 1, DB Period: Percentage of Participants Who Achieved >=75% Reduction From Baseline in Eczema Area and Severity Index (EASI) Score (EASI-75) at Week 16

• Endpoint type: Binary: the percentage of participants with the event (counts rebuilt from the posted percentages and group sizes).
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • DB Period: Etrasimod 2 mg: 23.3% (7/30) versus 14.3% (4/28) on control; risk difference 9.0 percentage points (95% CI -10.9 to 29.0), risk ratio 1.63 (0.54–4.98); unadjusted two-proportion z-test p = 0.380.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between DB Period: Etrasimod 2 mg and the control. The interval gives the range of effects that remain compatible with the data.

Part 1, DB Period: Percent Change From Baseline in EASI Score at Week 16

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • DB Period: Etrasimod 2 mg: mean -53.87 versus -24.65 on control; difference -29.22 (95% CI -54.92 to -3.52), standardized effect d = -0.59; z-test p = 0.026.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for DB Period: Etrasimod 2 mg than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The secondary outcomes provide context from two different EASI-based measures: a responder definition requiring at least a 75% reduction from baseline, and percent change from baseline in EASI score. Across these endpoints, the observed pattern is not fully uniform. The responder outcome numerically favored etrasimod, while the average percentage change also showed a larger reduction in the etrasimod group. The primary IGA response comparison, by contrast, was numerically lower in the etrasimod group. This variation across measures underscores that results depend on the endpoint definition and should not be collapsed into a single claim.

The secondary results do not resolve the uncertainty in the primary endpoint. The sponsor-reported interval for the binary EASI responder comparison includes no difference, while the reported interval for the continuous EASI change comparison does not. These are distinct analyses of distinct outcomes, and the continuous endpoint's result does not replace the primary endpoint or establish a consistent effect across all measures.

Unadjusted secondary results carry less inferential weight when several outcomes are examined because repeated testing can make chance findings more likely. The registry record does not report whether multiplicity adjustment was used, nor does it give a complete statistical testing hierarchy. The secondary findings are therefore best treated as supportive or exploratory evidence, interpreted alongside the primary result, its small number of responses, and its wide interval—not as a separate confirmation that settles the treatment comparison.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Part 1, DB Period: Percentage of Participants Who Achieved >=75% Reduction From Baseline in Eczema Area and Severity Index (EASI) Score (EASI-75) at Week 16
• Part 1, DB Period: Percent Change From Baseline in EASI Score at Week 16

9. Statistical Interpretation

10. Statistical Methods Explained

The primary outcome is binary: each participant either met the IGA response definition at Week 16 or did not. The natural descriptive summaries for a binary outcome are the number meeting the definition and the percentage within each assigned group. In this trial, the posted counts are 1 and 2, and the arm percentages are 3.3% and 7.1%. When event counts are sparse, percentages can look quite different after only a small change in the count. That general property is especially relevant when interpreting this comparison.

What does the percentage difference represent?

A risk difference, also called a difference in proportions, subtracts the comparator group's response proportion from the intervention group's response proportion. The sponsor reported the difference as a difference in percentage, with etrasimod compared with placebo. Its estimate was -3.76 percentage points. A negative sign means the observed response percentage was lower in the etrasimod group under that ordering. This is a description of the estimate, not proof that the treatment caused the difference.

In general, an absolute difference is often easier to interpret than a relative measure because it directly expresses the change in the proportion meeting the endpoint. Relative measures such as a risk ratio compare proportions by division, and odds ratios compare odds rather than probabilities. With few events, relative measures can be particularly unstable. The posted primary analysis is reported as a difference in percentage; the registry record does not report a sponsor-reported primary risk ratio or odds ratio.

How should the confidence interval be read?

A confidence interval expresses uncertainty around an estimated effect under the assumptions of the method used. In general, a 95% confidence interval is generated by a procedure that, over repeated comparable studies, would cover the underlying effect at the stated rate if its assumptions hold. It is not a range containing a known fixed percentage of participants, nor does it assign a probability to the true effect after the data have been observed.

The sponsor's primary interval extends from -16.36 to 8.83 percentage points. Because it includes zero, the data are compatible with no difference under this interval-based comparison. Its negative and positive limits also indicate that the estimate is not precise enough to determine the direction of the difference. This interpretation is about statistical uncertainty, not whether any particular effect would be important to patients.

What is the role of the reported analysis?

The sponsor reports a Cochran-Mantel-Haenszel analysis for the primary comparison. This method is used for categorical outcomes and can combine information across strata when a stratified analysis is specified. The registry record does not report the stratification factors or enough detail to determine how the method was implemented, so those details should not be inferred. The sponsor also reports a 95% interval and a p-value, but the p-value is not repeated because the registry value has more than three decimal places.

The posted recalculation is a simple, unadjusted comparison from the displayed group summaries. It is useful as a check on the direction and broad scale of the result, but it is not the same analysis as the sponsor's. The registry does not flag a discrepancy between the recalculation and the sponsor result. In general, analyses can differ because of methods, adjustments, or the exact population and assumptions used. The record does not supply details that would permit a complete reconciliation beyond the reported methods.

Why does the analysis population matter?

The primary endpoint description states that the FAS includes all randomized participants irrespective of whether they received a dose of study intervention, with participants analyzed in the treatment groups to which they were randomized. This is an intention-to-treat-style principle: retaining participants in their assigned groups preserves the basis of the randomized comparison. The record also refers to participants with baseline IGA at least 2 in the primary endpoint population description. The complete wording and any further population rules are not reported in the registry record.

How missing outcomes were handled can affect a binary endpoint, especially when event counts are sparse. For example, the analysis could depend on whether unavailable Week 16 assessments were excluded or handled under a specified assumption. The registry record does not report the missing-data method, the number of unavailable primary assessments, or sensitivity analyses for missing data. No particular approach should be assumed.

How should p-values and multiple outcomes be understood?

In general, a p-value measures how unusual data at least as incompatible with a specified null model would be if that model and the analysis assumptions were correct. It is not the probability that the null hypothesis is true, and it does not measure the size or clinical importance of an effect. For the primary result, the interval already conveys the key issue: the estimate is imprecise and compatible with differences in either direction.

Testing several endpoints can increase the chance that at least one result appears unusual by chance. Statistical methods that control multiplicity can address this issue, but the registry record does not report whether the secondary tests were adjusted or how outcomes were prioritized for inference. The posted secondary findings should therefore be read as exploratory context rather than as independent confirmation of the primary result.

11. Confidence Intervals and Precision

The sponsor's 95% confidence interval for the primary difference in percentage runs from -16.36 to 8.83 percentage points around an estimate of -3.76 percentage points. Its span across zero means that the data do not pin down whether the response percentage was lower or higher with etrasimod. The limits also permit effects larger in magnitude than the point estimate. The interval therefore communicates substantial uncertainty, not evidence that the effect is exactly zero.

The small number of observed primary responses is central to this uncertainty. There were 1 response in the etrasimod group and 2 in the placebo group. With so few events, the estimate depends heavily on each individual response classification. The displayed arm percentages should not be read as stable estimates of what would necessarily occur in a much larger or different population.

In general, confidence intervals reflect both the estimated effect and the amount of information available under the analysis method. A larger sample can improve precision, but precision also depends on event frequency and study design. The registry record does not report a target interval width or an original precision goal. The sample-size illustrations use the observed effects and stated planning assumptions; they are not evidence that the trial was designed to achieve the precision seen in the posted result.

The interval is specific to the sponsor's reported analysis and the Week 16 primary endpoint. It does not describe uncertainty for every secondary outcome, long-term safety, or participants outside the study population. Its inclusion of both negative and positive values should guide interpretation: the observed direction is not established with precision by this comparison.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The sample-size illustrations express planned enrollment as participants per arm, not as a total across the two arms. The endpoint is not time-to-event, so the illustration is not a total-event target. The calculations use a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. The effect to detect is set as the stated fraction of the observed effect. The original trial's own design assumptions and sample-size justification are not reported in the registry record.

The 80% power column describes the number of participants per arm estimated to give an 80% chance of rejecting the null under the planning assumptions if the specified effect is the true effect. The 90% power column gives the corresponding per-arm planning figure for a 90% chance. These are design calculations conditional on assumptions, not guarantees about what a future study will observe.

Rows that plan for a smaller fraction of the observed effect require more participants per arm. This is expected in general: smaller differences are harder to distinguish from random variation, so more information is needed to detect them with the same planned power and significance level. The illustrations are based on the observed estimate, which itself is uncertain, and should be treated as planning examples rather than as a recommended design. This is not observed power.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, p₀ and p₁ are the control and treatment proportions, and p̄ is their average.

Worked calculation for this trial

1. Control proportion p₀ = 0.071; treatment proportion p₁ = 0.033; average p̄ = 0.052.
2. First term: z_1−α/2 × √[2p̄(1−p̄)] = 1.96 × 0.3151 = 0.6175.
3. Second term: z_1−β × √[p₀(1−p₀) + p₁(1−p₁)] = 0.842 × 0.3139 = 0.2642.
4. n = (0.6175 + 0.2642)² / (-0.0381)² = 535.7, rounded up to 536 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
p0 <- 0.0714285714285714                          # control proportion
p1 <- 0.0333333333333333                          # treatment proportion
n_per_arm <- function(power, frac = 1) {
  q1 <- p0 + (p1 - p0) * frac               # smaller effect = fraction of the observed difference
  pbar <- (p0 + q1) / 2
  z_b <- qnorm(power)
  ceiling(round((z_a * sqrt(2 * pbar * (1 - pbar)) + z_b * sqrt(p0 * (1 - p0) + q1 * (1 - q1)))^2 / (q1 - p0)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (unrounded n per arm)
cat("power.prop.test:", round(power.prop.test(p1 = p0, p2 = p1, power = 0.80)$n, 1), "\n")

# Simulation: how often does the z-test reject at the 80%-power sample size?
set.seed(5732454)
n    <- n_per_arm(0.80)
reps <- 20000
x0 <- rbinom(reps, n, p0); x1 <- rbinom(reps, n, p1)
ph <- (x0 + x1) / (2 * n)
z  <- ((x1 - x0) / n) / sqrt(ph * (1 - ph) * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(z) > z_a, na.rm = TRUE), reps))

Output from running the code

100% of observed effect: n per arm = 536 (80% power), 717 (90% power)
 75% of observed effect: n per arm = 1,035 (80% power), 1,385 (90% power)
 50% of observed effect: n per arm = 2,512 (80% power), 3,362 (90% power)
power.prop.test: 535.7 
Simulated power at n = 536 per arm: 0.807 (20000 replicates)

The simulation draws many pairs of event counts at the planned sample size and counts how often the two-proportion z-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Analyses Reported by the Sponsor

The sponsor's reported primary comparison uses a Cochran-Mantel-Haenszel method and gives a difference in percentage of -3.76, with a 95% confidence interval from -16.36 to 8.83. That interval includes no difference. The sponsor's result is the trial's own reported analysis and should be distinguished from the simple unadjusted recalculation based on the displayed group summaries.

The recalculation is a useful check of the summary data, but it does not reproduce every feature of the sponsor's method. The sponsor's analysis and the unadjusted calculation both leave the primary comparison uncertain; neither yields a precise conclusion about the direction of the difference. The registry record does not flag a discrepancy between them. Details such as stratification factors and other implementation choices are not reported in the registry record, so a more exact reconciliation is not possible from the record alone.

The sponsor also reported a p-value for the primary analysis. The central interpretive issue remains the broad interval spanning both sides of no difference. A p-value alone would not express the size or precision of the effect, and should not replace the effect estimate and its interval.

15. Multiplicity, Missing Data and Analysis Populations

The registry record lists 17 outcome measures, while two secondary outcomes have posted results in addition to the primary result. The record does not report a complete statistical analysis plan, a hierarchy for testing outcomes, or whether multiplicity adjustments were applied. It is therefore not possible to determine from the registry record whether the sponsor treated the secondary outcomes as confirmatory or exploratory for formal inference.

Multiplicity matters because testing several endpoints can increase the chance of obtaining at least one apparently notable result even when no treatment effect exists. In general, adjustment procedures can control the overall error rate across a family of tests, but they require a prespecified definition of the family and method. No such details are reported in the registry record. The secondary findings should consequently be interpreted with more caution than a single prespecified primary comparison.

The primary population is described as the FAS, including randomized participants whether or not they received a dose, analyzed according to randomized group. The endpoint description also refers to participants with baseline IGA at least 2. The record does not report further details sufficient to clarify the full population rules. The number of missing Week 16 assessments, the handling of missing primary or secondary data, and sensitivity analyses for missing data are not reported in the registry record.

The registry record does not report interim analyses, stopping rules, the original sample-size justification, or the protocol's planned statistical procedures beyond the methods identified for the posted analyses. It also does not report why the trial was terminated. These omissions limit assessment of how the posted analyses relate to the full original plan, but they do not establish that any particular analysis or decision was made.

16. 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: pneumothorax spontaneous (3.3%).

For the double-blind period, the registry lists 0 serious adverse events among 30 participants at risk in the etrasimod group and 0 among 28 at risk in the placebo group. The posted safety information also separates open-label extension groups and groups identified by their double-blind treatment followed by open-label etrasimod. Those categories include 1 serious adverse event among 30 at risk in the extension group continuing etrasimod, 0 among 28 in the extension group switching from placebo, 1 among 30 in the combined etrasimod sequence, and 0 among 28 in the combined placebo-then-etrasimod sequence. The categories are reported separately and should not be added together.

The registry lists “Pneumothorax spontaneous” at 3.3% as a top serious term, without specifying in the posted summary which displayed group it belongs to. The registry lists 0 deaths in each displayed safety group. These figures describe the posted categories and do not by themselves establish comparative safety; exposure periods and group definitions differ across the double-blind and extension summaries. The registry record does not report enough detail to assess all adverse events or their timing and relationship to treatment.

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

The primary finding is a Week 16 comparison of a specifically defined IGA response in adults with moderate-to-severe atopic dermatitis and a history of prior systemic treatment failure. The observed response percentage was lower in the etrasimod group than in the placebo group, but only 1 and 2 participants, respectively, met the response definition. The sponsor's 95% confidence interval includes no difference and allows effects in either direction.

That result does not establish that etrasimod is less effective, more effective, or equivalent to placebo. Failure to distinguish a difference is not proof that the treatments are the same. Conversely, secondary outcome patterns that favor etrasimod on some measures do not establish a treatment benefit, particularly when the primary comparison is imprecise and multiplicity handling is not reported. The interpretation should remain tied to the endpoint, analysis, and period actually reported.

The primary outcome concerns the double-blind period at Week 16. It does not answer every question about longer-term outcomes, all aspects of disease severity, or the safety profile over time. The registry summary describes an additional open-label period for some participants, but the primary comparison is not a randomized placebo comparison during that later period. The posted safety categories should be read according to their separate group labels and observation periods.

These results are evidence about the participants and analyses recorded in this trial, not medical advice and not a recommendation for any individual. The study's terminated status and its enrollment of 58 also form part of the context, but the registry does not report the reason for termination or enough original design detail to infer what motivated it. The appropriate conclusion is limited: the posted primary data are sparse and imprecise, and do not settle the direction or magnitude of the Week 16 response difference.

18. Why This Trial Matters Statistically

This trial illustrates why an effect estimate should be interpreted together with its uncertainty and the number of observed events. The primary endpoint percentages might appear to invite a simple comparison, but they arise from only 1 response in the etrasimod group and 2 in the placebo group. With so few events, the point estimate is highly sensitive to individual outcomes, and the sponsor's interval spans both negative and positive differences.

It also demonstrates that different endpoints can tell different descriptive stories. The primary IGA response, an EASI responder definition, and percent change in EASI do not measure precisely the same feature of disease status. A result on one endpoint cannot automatically be transferred to another. Considering the whole pattern is useful, but it does not remove the need to respect the primary endpoint and the uncertainty in each analysis.

Finally, the record highlights the value of reporting analytic details. The primary population and sponsor method are identified, but the original sample-size justification, missing-data handling, multiplicity plan, and reason for termination are not reported in the registry record. Those details help readers judge how results relate to the planned analysis and what conclusions the evidence can support. Their absence is a limit on interpretation, not evidence that a particular procedure was or was not used.

19. 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.
• Participant counts were reconstructed from posted percentages and arm sizes, so small rounding differences are possible.

The primary comparison is based on very few IGA responders, which limits precision and makes the observed percentages sensitive to individual outcomes. The sponsor's interval is wide and includes differences in either direction. The registry record reports an enrollment of 58 and the posted analysis groups, but it does not report enough baseline information to assess comparability on measured characteristics or describe the participants in further detail.

The trial is listed as terminated, but the reason and timing of the termination decision are not reported in the registry record. The original sample-size justification, design assumptions, interim-analysis plan, stopping rules, and complete statistical analysis plan are also not reported. Missing-data counts, the method used for missing Week 16 outcomes, and sensitivity analyses are not reported. These gaps limit evaluation of the planned-versus-posted analysis and potential effects of incomplete follow-up.

The registry identifies the sponsor's primary method but does not report its implementation details, including any stratification factors. It also does not report whether secondary analyses were adjusted for multiplicity. The secondary findings therefore warrant caution and cannot be treated as independent confirmation without knowing the prespecified testing plan.

The primary efficacy comparison is limited to Week 16 in the double-blind period. The registry summary describes a possible open-label continuation, but the primary endpoint does not establish longer-term comparative efficacy. Safety results are shown across distinct period and treatment-sequence categories, and the posted summary does not give enough detail to combine or compare those observations as if they represented the same exposure. The top serious adverse event term is not linked to a particular group in the posted summary.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: A Study to Learn About the Study Medicine Etrasimod in Adults With Moderate to Severe Atopic Dermatitis (AD) Who Have Already Tried Treatments Taken by Mouth or by Injection — NCT05732454.
• Registry record last updated 2025-05-08; status last verified 2025-04.
• Results first posted 2025-05-08.
• 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.

23. Record Summary

ClinicalTrials.gov record NCT05732454 describes a randomized, quadruple-masked, parallel-group Phase 2/3 study of etrasimod 2 mg once daily versus oral placebo in adults with moderate-to-severe atopic dermatitis and a history of prior systemic treatment failure. The posted enrollment is 58, and the record lists the study status as terminated.

The primary outcome was IGA response at Week 16 during the double-blind period. The sponsor reported a difference in percentage of -3.76, with a 95% confidence interval from -16.36 to 8.83. The posted response counts were 1 with etrasimod and 2 with placebo. The interval includes no difference and remains compatible with effects in either direction.

The record also posts two EASI-based secondary outcomes and safety summaries for double-blind and open-label groups. The reason for termination, original design assumptions, missing-data procedures, and multiplicity plan are not reported in the registry record.