A Study to Evaluate Safety and Efficacy of Infliximab in Chinese Participants With Moderate to Severe Plaque-type Psoriasis: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study to Evaluate Safety and Efficacy of Infliximab in Chinese Participants With Moderate to Severe Plaque-type Psoriasis (NCT01177800), a randomized phase 3 study. The primary outcome is Percentage of Participants Who Achieved a Greater Than Equal to 75 Percent Response in Psoriasis Area and Severity Index (PASI).

2. Clinical Question

3. Trial Design

This was a Phase 3, randomized, double-blind, placebo-controlled study with a parallel-group model. It enrolled 129 participants and is recorded as completed. The study start is listed as 2009-02, with primary completion in 2010-02. The sponsor named in the registry is Xian-Janssen Pharmaceutical Ltd. The condition is psoriasis, and the population specified in the title and summary is Chinese participants with moderate to severe plaque-type psoriasis.

The registry lists 84 participants in the infliximab group and 45 in the placebo group for the primary endpoint. The primary analysis population is described as intent to treat, including all participants randomly assigned to either group. The arm descriptions specify intravenous infusions. The placebo-arm schedule includes infliximab administrations during the treatment period, while the infliximab-arm description is truncated after mentioning placebo. Consequently, the full treatment sequence for both groups cannot be reconstructed from the registry record alone.

Randomization and double masking are stated, but the method used to generate the allocation sequence, conceal allocation, or maintain masking is not reported in the registry record. The registry does not report the original sample-size justification, planned effect size, or the assumptions used to design the trial. These omissions matter when distinguishing the trial’s original design from the separate sample-size planning illustrations associated with the posted results.

The primary endpoint was assessed at Week 10. The record also lists secondary outcomes concerning change in Dermatology Life Quality Index (DLQI) at Week 10 and the percentage with a static Physician Global Assessment (PGA) score less than or equal to 1 at Week 10. Numeric results are posted for the PGA outcome, but a DLQI result is not reported in the registry record. Five outcome measures and four analyses are recorded, without a complete outcome-by-outcome analysis plan in the registry record.

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: Intent to treat (ITT) population included all participants randomly assigned to Infliximab or placebo group.

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 a Greater Than Equal to 75 Percent Response in Psoriasis Area and Severity Index (PASI), measured over Week 10.

The primary endpoint is the percentage of participants who achieved a PASI 75 response at Week 10. A participant meets this definition by having at least a 75 percent relative improvement from baseline in the PASI score. The registry defines PASI as an assessment of erythema, induration, and scaling across four body regions: the head, trunk, upper extremities, and lower extremities. Each assessment uses a scale from 0, meaning none, to 4, meaning very severe. The total score ranges from 0, indicating no disease, to 72, indicating maximal disease.

A responder endpoint turns a continuous score into a yes-or-no outcome: each participant either meets the response threshold or does not. Reporting the percentage who meet a prespecified threshold can make group results easier to interpret than comparing score changes alone. The threshold also focuses attention on the proportion reaching a particular degree of improvement, rather than the average amount of change across everyone.

This endpoint is specific to the Week 10 assessment and to the PASI 75 definition in the registry. It does not, on its own, describe the full course of symptoms, the durability of response after that assessment, or other aspects of health. The registry’s primary population is intent to treat, meaning participants are included according to their randomized assignment. The record does not describe how missing Week 10 PASI assessments were handled.

7. Results Posted in the Registry

• Infliximab: 81.0% (68/84) versus 2.2% (1/45) on control; risk difference 78.7 percentage points (95% CI 69.3 to 88.2), risk ratio 36.43 (5.23–253.71); 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 With Static Physician Global Assessment (PGA) Score Less Than Equal to 1 at Week 10

• 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:
  • Infliximab: 88.1% (74/84) versus 6.7% (3/45) on control; risk difference 81.4 percentage points (95% CI 71.4 to 91.5), risk ratio 13.21 (4.42–39.54); 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 Infliximab than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The registry identifies two secondary outcomes: change from baseline in DLQI at Week 10 and the percentage with a static PGA score less than or equal to 1 at Week 10. Numeric results are posted for the PGA outcome, while the DLQI result is not reported in the registry record. Across the available numeric secondary result and the primary endpoint, the observed pattern favors the infliximab group on the recorded response measures. The outcomes are related in that each describes a different aspect of status at Week 10, but they are not interchangeable measures.

The PGA outcome is a categorical assessment, while DLQI concerns dermatology-related quality of life and is described as a change from baseline. A pattern across distinct measures can provide context for the primary result, but it does not make the outcomes equivalent or resolve the limitations of any one measure. The registry lists five outcome measures and four analyses, but it does not provide a complete mapping of every outcome to an analysis or a full statistical analysis plan.

Secondary results generally carry less confirmatory weight than a prespecified primary result, especially when the number of tested outcomes and the approach to multiple testing are unclear. Testing several outcomes increases the chance that at least one apparently notable result may arise without a corresponding underlying effect. In general, adjustment procedures can control that risk, but the multiplicity approach for this trial is not reported in the registry record. The posted secondary p-value should therefore be read as an unadjusted result, not as proof of a family-wide error-controlled conclusion.

The secondary findings can be considered supportive context for the primary comparison, but they do not independently establish the same claim as the primary endpoint. The absence of a posted DLQI result also limits assessment of whether the overall pattern extends to the quality-of-life measure. No conclusion about that outcome can be drawn from a numeric result that is not reported in the registry record.

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

• Change From Baseline in Dermatology Life Quality Index (DLQI) at Week 10
• Percentage of Participants With Static Physician Global Assessment (PGA) Score Less Than Equal to 1 at Week 10

9. Statistical Interpretation

10. Statistical Methods Explained

The primary outcome is binary: each participant is counted as either achieving PASI 75 or not achieving it. The registry reports the number and percentage of responders in each randomized group. The infliximab group had 68 responders among 84 participants, reported as 81.0%; the placebo group had 1 responder among 45 participants, reported as 2.2%. Keeping both counts and percentages in view helps make clear how much information underlies each percentage.

What does the Fisher exact test assess?

The registry names Fisher Exact as the method for the primary between-group test. In general, Fisher’s exact test evaluates whether the observed distribution of a binary outcome across groups is compatible with no association between group and outcome, using the fixed margins of the comparison. It is often useful when counts are small or when the expected counts in a contingency table may be low. The registry reports p < 0.001 for this test.

A p-value is a measure of compatibility between data and a specified null model, conditional on the test’s assumptions. It does not quantify the probability that the result happened “by chance,” nor does it establish that a treatment effect is clinically important. The p-value is also not a measure of precision. Precision is better considered through an interval estimate around the group comparison and through the amount of observed data.

What is the unadjusted recalculation?

The recalculation uses the posted responder counts to describe the unadjusted comparison between randomized groups. “Unadjusted” means the comparison is not corrected for other measured characteristics or covariates. The reported difference in response proportions and its interval are useful summaries of the contrast, while the group percentages show the underlying event frequency. These simple summaries do not replace any more detailed model that may have been used by the sponsor.

The recalculated result and the registry-reported analysis both have p < 0.001. The record does not indicate a discrepancy between them. A recalculation from summary counts can check whether a basic unadjusted result is consistent with the posted data, but it cannot reproduce analyses that depend on individual participant data, covariate adjustment, imputation, or other information not reported in the registry.

Why are absolute proportions useful?

The percentage in each arm describes the observed frequency of response within that group. The difference between those percentages expresses the contrast on an absolute scale; a relative measure instead compares one group’s response frequency with the other group’s. Absolute and relative summaries answer different questions and can look different when the comparison group has few events. The registry-derived materials include an unadjusted risk-difference comparison, but the precise difference and interval are best read from the associated statistical display.

For any binary endpoint, a response percentage depends on the endpoint definition, assessment time, and participants included in the denominator. Here, the endpoint is a PASI 75 response at Week 10 and the primary population is identified as intent to treat. The registry does not state how missing Week 10 data were handled, so the denominator and missing-data approach cannot be independently assessed from the record alone.

What does a confidence interval add?

In general, a confidence interval gives a range of values compatible with the data under the method used to calculate it. It conveys uncertainty around an estimate, whereas a p-value tests compatibility with a particular null value. An interval that excludes the null value for a difference supports evidence of a between-group contrast under the interval method’s assumptions. The confidence level and full interval-calculation method are not reported in the registry record, so interpretation should not assume details that are absent.

The trial’s comparison is an unadjusted summary based on observed binary outcomes. The registry does not describe interim analyses, a data monitoring procedure, a covariate model, or a multiplicity strategy. General statistical concepts can explain how the displayed methods work, but they cannot fill in these missing protocol details. The statistical findings should therefore be read as the reported endpoint comparison, with the stated population and time point, rather than as a complete account of every analytic decision.

11. Confidence Intervals and Precision

The reported percentages are estimates from the participants assessed in each randomized group, not exact descriptions of every participant who might be eligible for a similar study. The primary outcome has 68 responders among 84 participants in the infliximab group and 1 among 45 in the placebo group. The group sizes and the event counts are relevant to precision: percentages based on limited counts can vary across studies even when the underlying response probabilities are similar.

The statistical materials include an unadjusted risk-difference estimate and an interval around it. An interval communicates a range of values compatible with the observed data under its calculation method. It is not a range containing a known fixed effect with certainty, and it does not account automatically for bias, missing data, or limitations in how participants were selected. The confidence level and interval method are not reported in the registry record, so the interval should be interpreted as presented without assuming those details.

The displayed primary result has a large separation between the two observed response percentages, and the reported Fisher exact test has p < 0.001. Statistical evidence against the null comparison and precision are related but distinct. The p-value summarizes compatibility with a null model; the interval describes uncertainty around an estimated contrast. Neither statistic addresses whether the endpoint captures every outcome of interest or whether the result applies to other populations and time points.

For the secondary PGA outcome, the record also gives group percentages and an unadjusted interval-based comparison. The same general cautions apply: interval estimates depend on the data and calculation method, and they do not account for unreported multiplicity procedures or missing-data handling. The registry does not provide a confidence interval for every listed outcome in a form that allows all analytic details to be checked.

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 figures are planning illustrations based on the observed effect, not the trial’s original design justification. The figures are participants per arm, not total event counts. They use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. Each planning row asks how many participants per arm would be needed if the effect to detect were 100%, 75%, or 50% of the observed effect. The original trial’s design assumptions and sample-size justification are not reported in the registry record.

The 80% power column gives the planning number of participants per arm associated with an 80% chance of rejecting the null hypothesis under the listed assumptions, if the specified effect were the true effect. The 90% power column gives the corresponding planning number for a 90% chance under those assumptions. These are prospective planning concepts; the numbers do not measure the probability that the completed trial found a real effect. This is not observed power.

For the primary endpoint, the planning illustrations list 5 participants per arm for 80% power and 6 for 90% power when planning for 100% of the observed effect. For 75% of the observed effect, the figures are 9 and 11 participants per arm. For 50% of the observed effect, they are 17 and 22 participants per arm. The associated curve should be read as a visual representation of how the planned sample size changes with the effect size used in the calculation.

Smaller effects are harder to distinguish from random variation, so they generally require more participants to achieve the same planned power. The illustration’s inputs are based on the observed effect in this trial, which can make the resulting numbers especially optimistic if the observed contrast is larger than the effect a future study aims to detect. The planning calculations also assume equal allocation and a normal approximation; actual design needs depend on the planned endpoint, analysis method, allocation, and other assumptions. These figures should not be interpreted as evidence that the original study was designed with those sample sizes in mind.

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 = 0.022; treatment proportion p₁ = 0.810; average p̄ = 0.416.
2. First term: z_1−α/2 × √[2p̄(1−p̄)] = 1.96 × 0.6970 = 1.3661.
3. Second term: z_1−β × √[p₀(1−p₀) + p₁(1−p₁)] = 0.842 × 0.4194 = 0.3530.
4. n = (1.3661 + 0.3530)² / (0.7873)² = 4.8, rounded up to 5 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 <- 0.0222222222222222                          # control proportion
p1 <- 0.80952380952381                          # 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(1177800)
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 = 5 (80% power), 6 (90% power)
 75% of observed effect: n per arm = 9 (80% power), 11 (90% power)
 50% of observed effect: n per arm = 17 (80% power), 22 (90% power)
power.prop.test: 4.8 
Simulated power at n = 5 per arm: 0.884 (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 registry’s reported primary analysis uses Fisher’s exact test and gives p < 0.001. The unadjusted recalculation from the posted summary counts also gives p < 0.001, and the record does not flag a discrepancy between the sponsor analysis and the recalculation. The sponsor’s own analysis is the primary reported analysis; the recalculation is a check based on the group counts and is not a substitute for the sponsor’s full analysis.

Recalculations from summary statistics are necessarily limited. They can reproduce a simple unadjusted comparison when the necessary counts are available, but they cannot verify any analysis that depends on participant-level records, adjustments, missing-data rules, or other procedures not described in the registry. The record does not provide enough information to determine whether any such procedures were used beyond the listed Fisher exact test.

The matching reported p-value does not establish that every analytic choice is identical, nor does it establish that all outcomes were analyzed according to a prespecified plan. It indicates that the posted primary comparison and the simple count-based recalculation lead to the same broad inferential result. The interpretation should continue to distinguish that result from the separate issues of effect size, precision, applicability, and safety.

15. Multiplicity, Missing Data and Analysis Populations

The registry reports a primary endpoint and lists multiple additional outcome measures. It also records five outcome measures and four analyses. The primary endpoint is the percentage achieving PASI 75 at Week 10; the listed secondary outcomes include DLQI change from baseline and a static PGA threshold at Week 10. The record does not describe a hierarchy for testing the outcomes, a family of hypotheses, or a correction for multiple comparisons. It also does not report whether any outcomes were designated exploratory.

Multiplicity matters because examining more than one endpoint can increase the chance of at least one apparently small p-value under a setting where no true effects exist. General approaches include adjusting significance thresholds or specifying an ordered testing procedure in advance. These are general statistical concepts, not descriptions of what this trial did. Since the multiplicity plan is not reported in the registry record, the secondary p-values should be treated as unadjusted evidence rather than assumed to have family-wise error control.

The primary population is explicitly described as intent to treat, including all participants randomly assigned to infliximab or placebo. That definition supports interpretation by randomized assignment, but the registry does not describe whether all randomized participants had a Week 10 endpoint assessment or how missing values were handled. It does not report imputation, a nonresponder rule, a complete-case analysis, or sensitivity analyses for missing data. Those methods can affect binary response percentages, so their absence limits a full audit of the analysis.

The record identifies Fisher’s exact test for the primary reported comparison, but other aspects of the statistical analysis plan are not reported. Interim analyses, stopping rules, subgroup plans, covariate adjustments, and the original sample-size justification are not reported in the registry record. Their absence should not be interpreted as evidence that such procedures were or were not used; it means the registry does not document them. The available evidence supports interpretation of the posted primary and secondary results as reported, with those analytic details unresolved.

16. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: pulmonary tuberculosis (2.4%), coronary artery disease (2.2%), tuberculous pleurisy (1.2%), pulmonary embolism (1.2%), metastatic pancreatic cancer (1.2%).

The registry’s serious adverse event summary records 4 participants affected among 84 in the infliximab group and 1 among 45 in the placebo group. For other adverse events, it records 58 participants affected among 84 in the infliximab group and 28 among 45 in the placebo group. These are counts of affected participants as represented in the registry summary; they do not indicate how many events each participant experienced or establish that an event was caused by a study treatment.

The registry lists serious-event terms including Pulmonary Tuberculosis at 2.4%, Coronary artery disease at 2.2%, and Tuberculous pleurisy, Pulmonary embolism, Metastatic Pancreatic Cancer, and Liver diseases at 1.2% each. The context and denominator for these term-level percentages are not reported in the registry record, so they should not be read as arm-specific risks or used to compare groups. Deaths are not reported in the registry record.

Safety summaries describe events recorded during the trial; they do not by themselves determine causality or provide a complete account of severity, timing, duration, or exposure-adjusted incidence. Those details are not reported in the registry record. The participant counts should therefore be read as descriptive safety information, separately from the efficacy endpoint and its statistical test.

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

The posted primary result describes a marked difference in the Week 10 PASI 75 response percentages between the randomized groups: 81.0% in the infliximab group and 2.2% in the placebo group. The registry reports p < 0.001 for the Fisher exact comparison, and the unadjusted recalculation from the posted counts also gives p < 0.001. Together, these findings indicate a strong statistical separation in the recorded endpoint for the participants included in the analysis.

The result does not establish that every participant responded, or that a particular individual would have the same result. Group summaries describe patterns across study participants and do not predict an individual outcome. Nor does a Week 10 response percentage describe response at every later time point. The registry does not provide a primary endpoint result at another time point in the information summarized for this analysis.

The finding is specific to the trial population, comparator, endpoint definition, and assessment time. The study concerned Chinese participants with moderate to severe plaque-type psoriasis and compared infliximab with placebo under a randomized, double-blind design. The result should not automatically be extended to other populations, disease settings, treatment schedules, or outcomes that are not represented in the record.

Statistical significance does not by itself resolve clinical importance, long-term effects, or the balance of potential benefits and harms. The registry’s safety summary records serious and other adverse events, but it does not establish causation or provide all details needed for a comprehensive safety assessment. The record also lacks information about missing-data handling, multiplicity procedures, and the original sample-size rationale. These gaps constrain how completely the posted results can be evaluated.

The appropriate interpretation is therefore narrow: the registry records substantially different Week 10 PASI 75 response proportions between the randomized groups, with a small p-value under the stated test. The result is an observed trial finding, not a guarantee, a complete treatment evaluation, or evidence about outcomes that were not reported.

18. Why This Trial Matters Statistically

This trial offers a clear example of the distinction between a binary endpoint, its underlying counts, and the statistical comparison between randomized groups. PASI 75 classifies participants by whether they cross a specified improvement threshold. The reported percentages make the group pattern readily visible, while the responder counts show the amount of data contributing to those percentages.

The result also illustrates why a p-value and an effect estimate answer different questions. Fisher’s exact test gives p < 0.001, indicating strong incompatibility with the no-association model under the test assumptions. The unadjusted risk-difference display describes the magnitude of the group contrast and its uncertainty. A small p-value alone does not communicate the size or precision of the contrast, and an estimated contrast alone does not summarize all design limitations.

The unequal group sizes and sparse placebo response make exact methods and interval interpretation relevant. A percentage can appear highly different when one group has very few events, while the amount of information still depends on both group sizes and counts. Reading the counts, percentages, test, and interval together is more informative than relying on any one measure.

The registry also demonstrates how missing methodological details affect interpretation. It identifies the primary population and sponsor-reported test, yet does not describe missing-data handling, multiplicity procedures, or the original sample-size assumptions. The sample-size planning illustrations are therefore distinct from the original trial design. Separating posted results from planning calculations and from unknown protocol details is essential for a disciplined statistical reading.

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 registry record is incomplete for several questions that would affect a full appraisal. The infliximab arm description is truncated, and the schedule cannot be fully reconstructed from that text. Although the placebo-arm description gives a sequence of placebo and infliximab infusions, the available description does not explain the complete treatment logic or timing in a way that resolves the truncated text. The record also does not report the randomization sequence method, allocation concealment, or the procedures used to maintain masking.

Details of the endpoint analysis are limited. The primary population is identified as intent to treat and Fisher’s exact test is named, but handling of missing Week 10 assessments, imputation, sensitivity analyses, and any adjustment for baseline factors are not reported in the registry record. The confidence level and calculation method for the interval estimate are also not reported. These omissions limit independent verification of the full analysis.

The record lists multiple outcomes but does not report a multiplicity strategy or a complete analysis plan. A numeric DLQI result is not reported in the registry record, and the reasons for its absence are not stated. The original sample-size justification and design assumptions are also not reported; the separate planning illustrations use the observed effect and should not be treated as the trial’s original rationale.

Finally, the safety summary gives participant counts and selected serious-event terms, but does not report enough context to establish event attribution, timing, exposure, or the denominator for the listed term-level percentages. Deaths are not reported in the registry record. These limitations do not erase the posted group findings, but they restrict conclusions beyond the recorded Week 10 endpoints and summarized safety information.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: A Study to Evaluate Safety and Efficacy of Infliximab in Chinese Participants With Moderate to Severe Plaque-type Psoriasis — NCT01177800.
• Registry record last updated 2014-09-12; status last verified 2014-09.
• Results first posted 2014-03-17.
• 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 records a completed randomized, double-blind, placebo-controlled Phase 3 parallel-group study of infliximab in Chinese participants with moderate to severe plaque-type psoriasis. Enrollment was 129, with 84 participants in the infliximab group and 45 in the placebo group for the primary endpoint. The primary outcome was PASI 75 response at Week 10 in the intent-to-treat population.

The posted primary response percentages were 81.0% for infliximab and 2.2% for placebo. The registry reports Fisher’s exact p < 0.001, and the unadjusted recalculation from the posted counts also gives p < 0.001. Numeric results are posted for the secondary PGA outcome, while a DLQI result is not reported in the registry record.

The record includes descriptive adverse-event counts but does not report deaths, missing-data procedures, multiplicity handling, or the original sample-size justification. Interpretation is therefore strongest for the specific Week 10 endpoint comparison and should remain bounded by the design and reporting details available in the registry.