A Study of JNJ-77242113 for the Treatment of Participants With Plaque Psoriasis Involving Special Areas (Scalp, Genital, and/or Palms of the Hands and the Soles of the Feet): Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study of JNJ-77242113 for the Treatment of Participants With Plaque Psoriasis Involving Special Areas (Scalp, Genital, and/or Palms of the Hands and the Soles of the Feet) (NCT06095102), a randomized phase 3 study. The primary outcome is Percentage of Participants Who Achieved an Investigator's Global Assessment (IGA) Score of 0 or 1 and a Greater Than or Equal to (>=) 2-Grade Improvement From Baseline at Week 16.

2. Clinical Question

The primary outcome combines a status threshold at Week 16 with a change requirement from baseline. A participant had to have an IGA score of 0 or 1 and a reduction of at least 2 grades to meet the endpoint. The registry reports the percentages in each randomized arm and a treatment difference from the sponsor’s Cochran-Mantel-Haenszel analysis.

The question is specific to the first 16 weeks, when the randomized comparison was JNJ-77242113 versus placebo. It does not ask whether participants maintained a response through Week 156 or compare the groups after the placebo arm began receiving JNJ-77242113. Those longer-term questions are not answered by the posted Week 16 primary result. The registry record describes the study as evaluating efficacy and safety in participants with plaque psoriasis affecting special areas, but the primary endpoint is a general IGA assessment of plaque psoriasis rather than a site-specific score.

3. Trial Design

The registry describes a Phase 3, multicenter, randomized, double-blind, placebo-controlled, parallel study of JNJ-77242113 in participants with plaque psoriasis involving special areas. Enrollment was 311. The study began on 2023-10-12, and the primary completion date was 2024-06-19. Its status is active, not recruiting.

Participants were assigned to JNJ-77242113 or placebo. The JNJ-77242113 arm received treatment from Week 0 through Week 156. The placebo arm received placebo from Week 0 through Week 16 and then JNJ-77242113 from Week 16 through Week 156. This means the placebo-controlled comparison relevant to the primary endpoint is the Week 16 comparison. The later treatment arrangement does not preserve a placebo comparison through the full stated treatment period.

The primary outcome was assessed in the full analysis set, defined in the registry record as all participants randomized at Week 0. The recorded arm sizes for this endpoint were 103 in the placebo arm and 208 in the JNJ-77242113 200 mg arm. The registry record does not report the method used to generate the randomization sequence, the allocation-concealment procedure, or the specific roles masked by double blinding.

The registry record does not report the original sample-size justification, planned power, or assumptions used to design the trial. Any sample-size illustrations derived from the posted treatment effect are therefore distinct from the study’s original design rationale. Likewise, the registry record does not report the complete statistical analysis plan or whether interim analyses were planned or conducted. The reported trial analysis and the record’s outcome definitions can be described, but details not stated in the registry cannot be inferred from the trial design label 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.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Full analysis set (FAS) included all participants who were randomized at Week 0 in the study. Non-responder imputation was applied for missing data after applying predefined intercurrent event rules.

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 Percentage of Participants Who Achieved an Investigator's Global Assessment (IGA) Score of 0 or 1 and a Greater Than or Equal to (>=) 2-Grade Improvement From Baseline at Week 16, measured over Week 16.

The primary endpoint is the percentage of participants who, at Week 16, had an Investigator’s Global Assessment score of 0 or 1 and an improvement of at least 2 grades from baseline. The IGA assesses plaque psoriasis by grading induration, erythema, and scaling. Each component is scored on a 5-point scale, and the final IGA score reflects their average, classified from cleared (0) through severe (4). Higher scores indicate more severe disease.

The endpoint uses both an absolute score and a change-from-baseline requirement. The absolute threshold identifies participants whose Week 16 assessment falls in the cleared or minimal categories. The improvement requirement means that reaching that threshold alone is not sufficient: the participant must also have improved by at least 2 grades relative to baseline. This combined definition can distinguish a low Week 16 score reached after substantial improvement from a low score that does not meet the specified change criterion.

As a percentage endpoint, the result describes the fraction of participants meeting the stated response definition in each arm. It does not describe the average IGA score, the degree of improvement among responders, or response at every affected site. The registry defines baseline as the closest measurement taken before or at the time of first study-drug administration. Missing data were handled using non-responder imputation after applying predefined intercurrent-event rules; the specific rules are not reported in the registry record.

IGA is used as a clinical assessment of overall plaque psoriasis severity. General statistical context: a prespecified categorical response endpoint can make a treatment comparison easier to interpret as the proportion meeting a clinically described threshold, while discarding information about differences among participants who do not meet that threshold. The posted endpoint does not by itself explain how the threshold was selected.

7. Results Posted in the Registry

• Arm 2: JNJ-77242113 200 mg: 56.7% (118/208) versus 5.8% (6/103) on control; risk difference 50.9 percentage points (95% CI 42.8 to 59.0), risk ratio 9.74 (4.44–21.36); unadjusted two-proportion z-test p = <0.001.

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.

Percentage of Participants Who Achieved a Scalp Specific (ss)-IGA Score of 0 or 1 at Week 16 Among Participants With a Baseline Ss-IGA Score >=3

• 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:
  • Arm 2: JNJ-77242113 200 mg: 65.9% (110/167) versus 10.6% (9/85) on control; risk difference 55.3 percentage points (95% CI 45.6 to 65.0), risk ratio 6.22 (3.32–11.65); unadjusted two-proportion z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the proportion with the event is statistically higher for Arm 2: JNJ-77242113 200 mg than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Percentage of Participants Who Achieved Psoriasis Scalp Severity Index (PSSI) 90 at Week 16 Among Participants With a Baseline Ss-IGA Score >=3

• 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:
  • Arm 2: JNJ-77242113 200 mg: 57.5% (96/167) versus 5.9% (5/85) on control; risk difference 51.6 percentage points (95% CI 42.6 to 60.6), risk ratio 9.77 (4.13–23.10); unadjusted two-proportion z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the proportion with the event is statistically higher for Arm 2: JNJ-77242113 200 mg than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Percentage of Participants Who Achieved Static Physician's Global Assessment of Genitalia (sPGA-G) Score of 0 or 1 at Week 16 Among Participants With a Baseline sPGA Score >=3

• 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:
  • Arm 2: JNJ-77242113 200 mg: 76.5% (75/98) versus 21.4% (9/42) on control; risk difference 55.1 percentage points (95% CI 40.1 to 70.1), risk ratio 3.57 (1.98–6.44); unadjusted two-proportion z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the proportion with the event is statistically higher for Arm 2: JNJ-77242113 200 mg than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The posted secondary outcomes extend the Week 16 assessment to scalp, genital, and hands-and-feet measures, as well as other response and symptom measures. Three secondary results have arm-level data and sponsor analyses reported in the record: scalp-specific IGA response, PSSI 90 response, and genital sPGA response. For each of these posted comparisons, the reported response proportion is higher in the JNJ-77242113 arm than in the placebo arm, and the sponsor-reported treatment difference is positive. The registry also lists additional secondary outcome definitions, including measures of hands and feet, overall IGA, symptoms, itch, and sexual frequency, but those additional results are not detailed in the posted result data used for this discussion.

The pattern across the reported site-specific endpoints is consistent in direction with the primary Week 16 IGA result: the primary comparison and the reported special-area measures all show higher response proportions in the JNJ-77242113 arm. These outcomes are related but not interchangeable. They use different scales, focus on different locations or symptoms, and may apply only to participants meeting baseline severity or symptom criteria. Their populations can therefore differ from the full analysis set used for the primary endpoint.

The registry record lists 32 outcome measures and 35 analyses, while 31 secondary outcomes are posted. General statistical context: when many outcomes are examined, the chance of obtaining at least one apparently positive result can rise if no adjustment or prespecified testing hierarchy is used. The registry record does not report a multiplicity adjustment or explain which secondary results, if any, were confirmatory. Accordingly, the secondary results should be interpreted as additional evidence about the measured outcomes, but carry less confirmatory weight than the designated primary outcome unless a broader testing plan is documented elsewhere in the record.

The secondary findings do not establish effects on every special-area measure or every symptom outcome listed in the registry. Nor can a pattern among the reported analyses resolve the missing information about multiplicity, subgroup sizes, or the statistical plan. Their value is in showing that the primary result has related Week 16 outcomes with a similar reported direction, while leaving the strength of confirmatory inference uncertain.

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

• Percentage of Participants Who Achieved a Scalp Specific (ss)-IGA Score of 0 or 1 at Week 16 Among Participants With a Baseline Ss-IGA Score >=3
• Percentage of Participants Who Achieved Psoriasis Scalp Severity Index (PSSI) 90 at Week 16 Among Participants With a Baseline Ss-IGA Score >=3
• Percentage of Participants Who Achieved Static Physician's Global Assessment of Genitalia (sPGA-G) Score of 0 or 1 at Week 16 Among Participants With a Baseline sPGA Score >=3
• Percentage of Participants Who Achieved Physician's Global Assessment of Hands and Feet (Hf-PGA) Score of 0 or 1 at Week 16 Among Participants With a Baseline Hf-PGA Score >=3
• Percentage of Participants Who Achieved an IGA Score of 0 at Week 16
• Percentage of Participants Who Achieved Psoriasis Symptom and Signs Diary (PSSD) Symptom Score of 0 at Week 16 Among Participants With a Baseline PSSD Symptom Score >0
• Percentage of Participants Who Achieved >=4-Point Improvement From Baseline in PSSD Itch Score at Week 16 Among Participants With a Baseline PSSD Itch Score >=4
• Percentage of Participants Who Achieved Genital Psoriasis Sexual Frequency Questionnaire (GenPs-SFQ) Item 2 Score of 0 or 1 at Week 16 Among Participants With a Baseline sPGA-G Score >=3 and a Baseline GenPs-SFQ Item 2 Score >=2

9. Statistical Interpretation

10. Statistical Methods Explained

The primary outcome is binary at the participant level: each participant either met the Week 16 IGA response definition or did not. The reported arm percentages describe the proportion classified as responders within each randomized arm. General statistical context: binary outcomes are commonly compared using proportions, risk differences, relative measures, or regression-based methods. These measures answer related but not identical questions, and their numeric scales differ.

What does the treatment difference represent?

The sponsor reported a treatment difference using the Cochran-Mantel-Haenszel method. The reported estimate is 51.1, with a 95% confidence interval from 42.1 to 58.8 and p < 0.001. The method is used to estimate a treatment comparison while accounting for stratification factors when those factors have been used in the analysis. The registry record names the method but does not report the stratification factors, the detailed model specification, or whether any additional adjustments were made. Those details should not be inferred from the method name.

The posted recalculation is an unadjusted comparison based on the summary event counts and randomized arm sizes. Its risk-difference estimate is 0.509, with a confidence interval from 0.428 to 0.590 and p < 0.001. “Unadjusted” means that this calculation does not incorporate the sponsor’s analysis structure or any covariates beyond the summarized groups. It provides a transparent check from the posted counts, but it is not the same analysis as the sponsor’s Cochran-Mantel-Haenszel result.

How should the p-value be read?

General statistical context: a p-value evaluates how compatible the observed data are with a specified null hypothesis under the assumptions of the statistical test. A small p-value indicates that data at least as discrepant from the null as those observed would be uncommon if that null hypothesis and the model assumptions were correct. It is not the probability that the null hypothesis is true, and it does not measure the size or practical importance of an effect. The registry reports p < 0.001 for the primary sponsor analysis and for the unadjusted recalculation.

The sponsor’s reported analysis is labelled superiority. That label describes the direction and purpose of the stated hypothesis test, not a guarantee about outcomes beyond the measured endpoint or beyond the studied population. The registry record does not report the full hierarchy of hypotheses or a complete testing strategy.

What does non-responder imputation mean?

The full analysis set includes all participants randomized at Week 0. For missing primary-outcome data, the registry says non-responder imputation was applied after predefined intercurrent-event rules. General statistical context: under non-responder imputation, a missing outcome is classified as not meeting the response definition, subject to the analysis’s specified rules. This can make the result depend on how missingness and intercurrent events are handled. The registry does not give the specific intercurrent-event rules, the amount or pattern of missing data, or sensitivity analyses assessing alternative assumptions. Consequently, it is not possible to evaluate from the registry record how robust the result is to other missing-data approaches.

The registry record does not report the trial’s original sample-size justification, planned power, or assumptions used in its design. The planning illustrations associated with the posted effect are calculations for hypothetical planning scenarios, not evidence about the design process or the trial’s probability of detecting an effect after data collection. The record also does not report whether interim analyses were planned or conducted.

For the secondary outcomes, the registry posts additional response measures and analyses. General statistical context: testing many outcomes can increase the chance that at least one result appears statistically notable by chance if the tests are interpreted without accounting for multiplicity. The registry record does not report whether a multiplicity procedure was used for these secondary analyses, which results were designated confirmatory, or how their hypotheses were ordered. Their reported p-values should therefore be read in light of that missing information.

Finally, the registry includes an outcome description, analysis population, named method, estimates, confidence limits, and p-values, but not every operational or analytic detail needed to reproduce the sponsor’s analysis. The reported analysis should be distinguished from the simpler recalculation based only on the posted summary statistics. Both describe the Week 16 data, but they do so using different analytical approaches.

11. Confidence Intervals and Precision

The sponsor’s primary treatment difference is 51.1, with a 95% confidence interval from 42.1 to 58.8. The interval describes a range of effect values compatible with the observed data under the sponsor’s analysis and its assumptions. Its width reflects uncertainty in the estimate; it is not a range containing a known fixed proportion of individual participant outcomes, nor does it mean that there is a 95% probability that the true effect lies in this particular interval.

The interval lies on the positive side of zero. In the sponsor’s comparison, zero would represent no treatment difference. The reported interval therefore aligns with the reported p-value of <0.001 and the superiority classification. The interval still allows a range of possible effect magnitudes; the point estimate alone should not be read as exact. The registry record does not report the stratification details needed to reproduce the sponsor’s confidence interval from the published summary.

The unadjusted recalculation has an estimate of 0.509 and a confidence interval from 0.428 to 0.590. This interval pertains to the recalculated risk difference, rather than the sponsor’s displayed treatment-difference scale. The two results arise from different analyses, and the sponsor’s own analysis is the reported trial analysis. General statistical context: a confidence interval conveys sampling uncertainty under the analysis assumptions, but does not account automatically for every source of uncertainty, such as outcome measurement, missing-data assumptions, multiplicity, or differences between trial participants and other populations.

Precision is also shaped by the number of participants contributing to an endpoint and by the frequency of the outcome. For this endpoint, the recorded arm sizes were 103 for placebo and 208 for JNJ-77242113 200 mg. The registry reports non-responder imputation for missing data, but does not report missing-data counts or sensitivity analyses. The confidence interval therefore describes uncertainty under the reported analysis; it cannot resolve uncertainty about unreported analytic choices or missing-data patterns.

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 are planning scenarios based on the observed effect, not the trial’s original design justification. For this binary outcome, the figures are participants per arm, not total events. They assume a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is set to a stated fraction of the observed effect. The registry record does not report whether these assumptions were used to plan the trial.

The 80% power column gives the number of participants per arm in a hypothetical design intended to have an 80% chance of rejecting the no-difference hypothesis if the assumed effect and planning assumptions hold. The 90% power column gives the corresponding number for a 90% target. These are design calculations, not summaries of what happened in this trial. They are not observed power.

The planning rows consider the full observed effect and smaller fractions of that effect. For planning for 100% of the observed effect, the illustration gives 12 participants per arm for 80% power and 16 for 90% power. For planning for 75% of the observed effect, it gives 19 and 25 participants per arm, respectively. For planning for 50% of the observed effect, it gives 36 and 47 participants per arm, respectively. Smaller assumed effects require more participants under the stated assumptions because a more modest difference is harder to distinguish from random variation.

These calculations are illustrations only. They do not establish that the original trial was adequately or inadequately powered, because the original design assumptions are not reported in the registry record. They also do not show the probability that this completed comparison is correct, or the probability that another study would produce the same finding. A planning calculation is conditional on its selected effect size and statistical assumptions; changing those assumptions can change the required sample size.

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 = 0.058; treatment proportion p₁ = 0.567; average p̄ = 0.313.
2. First term: z_1−α/2 × √[2p̄(1−p̄)] = 1.96 × 0.6557 = 1.2851.
3. Second term: z_1−β × √[p₀(1−p₀) + p₁(1−p₁)] = 0.842 × 0.5480 = 0.4612.
4. n = (1.2851 + 0.4612)² / (0.5091)² = 11.8, rounded up to 12 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 <- 0.058252427184466                          # control proportion
p1 <- 0.567307692307692                          # 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(6095102)
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 = 12 (80% power), 16 (90% power)
 75% of observed effect: n per arm = 19 (80% power), 25 (90% power)
 50% of observed effect: n per arm = 36 (80% power), 47 (90% power)
power.prop.test: 11.8 
Simulated power at n = 12 per arm: 0.834 (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 primary analysis is reported as a Cochran-Mantel-Haenszel treatment difference of 51.1, with a 95% confidence interval from 42.1 to 58.8 and p < 0.001. The registry labels this result as superiority. This is the trial’s reported inferential analysis and should be kept distinct from a recalculation using only the posted summary counts.

The unadjusted recalculation gives a risk difference of 0.509, with a confidence interval from 0.428 to 0.590 and p < 0.001. It uses the arm-level event counts and sizes and does not reproduce the sponsor’s named method. The displayed estimates use different scales and analytical approaches. Their close correspondence in direction is consistent with both analyses describing a higher response proportion in the JNJ-77242113 arm, but the recalculation does not validate every feature of the sponsor’s analysis.

General statistical context: a summary-statistic recalculation can serve as a check that the posted arm counts and an unadjusted contrast tell a coherent story. It cannot replace an analysis that accounts for design features or stratification not included in the summary data. The registry record does not identify the sponsor analysis’s stratification factors, so the detailed reason for any difference between the estimates cannot be determined from the record. The sponsor’s analysis remains the relevant reported result; the recalculation is supplementary.

15. Multiplicity, Missing Data and Analysis Populations

The registry record identifies a primary outcome and lists 32 outcome measures and 35 analyses. It also posts 31 secondary outcomes. The primary endpoint is the Week 16 percentage meeting the specified IGA response definition. The record reports the sponsor’s primary Cochran-Mantel-Haenszel analysis, but it does not provide a complete statistical analysis plan or a full hierarchy of hypotheses.

Multiplicity is relevant when multiple endpoints, time points, subgroups, or comparisons are tested. General statistical context: if several hypotheses are tested and each is interpreted using an unadjusted significance threshold, the overall chance of at least one false-positive result can be greater than for a single test. Methods such as a prespecified hierarchy or multiplicity adjustment can address this issue, but the registry record does not report whether such a method was used for the secondary analyses. It also does not identify which secondary outcomes were intended to be confirmatory or how results were prioritized.

The primary endpoint analysis population is the full analysis set, defined as all participants randomized at Week 0. The record states that non-responder imputation was applied for missing data after predefined intercurrent-event rules. This conveys the general approach to missing outcomes, but not the detailed rules. The registry record does not report how many endpoint values were missing, the reasons for missingness, the number of participants affected by each intercurrent event, or sensitivity analyses under alternative missing-data assumptions.

Those omissions limit evaluation of robustness. General statistical context: conclusions from an analysis with imputed outcomes depend partly on the assumptions and rules used to classify missing data. Non-responder imputation treats missing outcomes as nonresponse, subject to the stated intercurrent-event rules, but the record does not provide enough detail to assess the impact of those rules. A sensitivity analysis can test whether conclusions change under plausible alternatives; whether such analyses were performed is not reported in the registry record.

The original sample-size justification, planned power, and trial-specific design assumptions are also not reported in the registry record. Likewise, whether interim analyses were planned or conducted is not reported. These gaps do not alter the figures reported for the primary analysis, but they constrain independent assessment of the prespecified design, multiplicity control, and sensitivity of the findings to missing-data choices.

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: covid-19 pneumonia (1.0%), sepsis (1.0%), sciatica (1.0%), acute respiratory failure (1.0%), hepatitis (0.5%).

The registry reports serious adverse events in 2 participants in the placebo arm, among 103 at risk, and 1 participant in the JNJ-77242113 200 mg arm, among 208 at risk. Other adverse events were reported in 15 participants in the placebo arm and 32 in the JNJ-77242113 arm. No deaths were reported in either arm. These are counts within the registry’s stated at-risk groups; they are not estimates of comparative safety adjusted for treatment duration or other factors.

The listed serious adverse-event terms include Covid-19 Pneumonia, Sepsis, Sciatica, Acute Respiratory Failure, and Hepatitis, with the percentages recorded for those terms shown in the registry. The record does not provide enough detail in this summary to establish how those terms were distributed between arms or to interpret their causes. A listed event does not by itself establish that study treatment caused it.

General statistical context: adverse-event counts describe events observed and recorded during a study; interpreting comparative safety also requires attention to exposure time, event definitions, severity, and the completeness of reporting. The registry summary does not provide exposure-adjusted rates or further detail on event duration and relatedness. These figures should therefore be read as descriptive safety information, not as a standalone estimate of the causal effect of treatment on adverse events.

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

The primary result describes the percentage of participants who met a particular IGA response definition at Week 16. The posted arm percentages are 5.8% for placebo and 56.7% for JNJ-77242113 200 mg. The sponsor reported a treatment difference of 51.1, with a 95% confidence interval from 42.1 to 58.8 and p < 0.001. These data show a higher observed Week 16 response proportion in the JNJ-77242113 arm for this endpoint, under the reported analysis.

The endpoint is not a measure of every aspect of plaque psoriasis or every outcome that may matter to participants. It combines an overall IGA threshold with an improvement-from-baseline requirement. It does not describe the full distribution of changes, the severity of symptoms among participants who did not meet the threshold, or response at every affected special area. The secondary measures broaden the outcomes considered, but the registry does not report results for every listed secondary outcome in the data.

The result is specific to the randomized comparison through Week 16. The placebo group then began receiving JNJ-77242113, according to the registered treatment schedule. The primary Week 16 comparison does not establish what would have happened under continued placebo, nor does it answer whether responses were maintained through Week 156. Long-term comparative conclusions are not available from this primary result.

Statistical significance does not mean the result is free of uncertainty. The confidence interval describes uncertainty under the sponsor’s analysis, and the registry does not report all details needed to assess stratification, missing-data sensitivity, or multiplicity handling. General statistical context: a trial estimate applies most directly to the participants, endpoint definition, assessment time, and analysis used. Extending it to different populations, treatment durations, or outcomes requires evidence beyond this one comparison.

The registry record describes a Phase 3 randomized, double-blind, placebo-controlled study, but the treatment result alone does not establish the mechanism of any observed difference or determine the balance of benefits and harms. The safety information is descriptive and does not replace a complete safety assessment. The result should be understood as evidence about the stated Week 16 response endpoint, with the record’s analytic and reporting limitations in view.

18. Why This Trial Matters Statistically

This trial is statistically informative because it uses a randomized, double-blind, placebo-controlled comparison for a defined Week 16 response outcome in plaque psoriasis involving special areas. Randomization provides a basis for comparing the assigned groups, while the endpoint specifies both a Week 16 status and a required improvement from baseline. Those features make the primary contrast interpretable as a comparison of proportions meeting a prespecified-looking clinical threshold, although the registry does not report the full protocol or analysis plan needed to verify all design details.

The endpoint also illustrates how outcome definition shapes statistical interpretation. A participant must meet both IGA criteria to count as a responder. This converts an assessment based on graded components into a binary result. General statistical context: binary outcomes are straightforward to communicate as percentages, but they do not retain all information about the size or pattern of change among participants. The selected threshold is therefore central to what the estimated treatment difference means.

The record presents a sponsor analysis and an unadjusted recalculation, making clear that analytical method matters. The sponsor used a Cochran-Mantel-Haenszel analysis, while the recalculation uses posted summary counts. Their estimates are reported on different scales and should not be treated as identical. The sponsor’s analysis is the trial’s reported inferential result; the recalculation is a separate summary-data comparison.

The registry also makes visible important limits in the available statistical record: the original sample-size justification is not reported, detailed missing-data rules are absent, and multiplicity handling for secondary endpoints is not stated. These are not merely technical omissions. They affect how confidently readers can assess the design rationale, robustness, and confirmatory status of the wider set of results. The trial therefore offers a clear primary comparison while also illustrating why endpoint definitions, analysis methods, uncertainty, and reporting completeness must be considered together.

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 confined to Week 16. Although the registered treatment schedules extend through Week 156, the placebo arm switches to JNJ-77242113 from Week 16 onward. The primary result therefore does not provide a long-term randomized comparison against continued placebo, and it does not establish the durability of the Week 16 response.

The study concerns participants with plaque psoriasis involving special areas, but the primary endpoint is an overall IGA assessment. It does not directly quantify response separately for the scalp, genital area, hands, or feet. The registry lists site-specific secondary outcomes, but only some secondary results are included in the posted result data. The primary endpoint also reduces the graded IGA assessment to a yes-or-no response classification, so it does not show the distribution of changes among participants who failed to meet the response threshold.

The primary analysis uses non-responder imputation after predefined intercurrent-event rules. The registry record does not report the detailed rules, missing-data counts, reasons for missingness, or sensitivity analyses. As a result, the influence of missing outcomes and intercurrent events cannot be evaluated fully from the record. The record also does not describe the stratification factors used in the sponsor’s Cochran-Mantel-Haenszel analysis.

Multiplicity is another limitation for interpreting the wider outcome set. The registry lists 32 outcome measures and 35 analyses, but does not report whether secondary analyses were adjusted for multiple testing or organized in a confirmatory hierarchy. The original sample-size justification, trial-specific power assumptions, and interim-analysis plans are also not reported in the registry record.

Finally, the safety summary gives counts of serious and other adverse events and reports no deaths, but does not provide exposure-adjusted comparisons or enough detail to establish causation. These limitations do not negate the primary reported result; they define the scope of conclusions that the registry record can support.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: A Study of JNJ-77242113 for the Treatment of Participants With Plaque Psoriasis Involving Special Areas (Scalp, Genital, and/or Palms of the Hands and the Soles of the Feet) — NCT06095102.
• Registry record last updated 2026-11-03; status last verified 2026-11.
• Results first posted 2026-06-25.
• 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.

23. Record Summary

The registry describes NCT06095102 as a Phase 3, multicenter, randomized, double-blind, parallel, placebo-controlled study of JNJ-77242113 in participants with plaque psoriasis involving special areas. Enrollment was 311, and the status is active, not recruiting. The registered treatment period extends through Week 156, with placebo given only through Week 16 in the comparator arm.

The primary outcome is the percentage achieving an IGA score of 0 or 1 and at least a 2-grade improvement from baseline at Week 16. The reported response percentages are 5.8% for placebo and 56.7% for JNJ-77242113 200 mg. The sponsor’s Cochran-Mantel-Haenszel treatment difference is 51.1, with a 95% confidence interval from 42.1 to 58.8 and p < 0.001.

The registry also reports selected Week 16 secondary analyses and descriptive adverse-event counts. It does not report the original sample-size justification, detailed intercurrent-event rules, or multiplicity handling for secondary outcomes. The primary result is specific to the stated endpoint, analysis population, and Week 16 comparison.