This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Study for the Treatment of Chronic Idiopathic Urticaria With High Doses of AERIUS (Desloratadine) (Study P04849) (NCT00536380), a randomized phase 4 study. The primary outcome is Change in the Urticaria Activity Score (UAS) From Baseline to the Final Week for Desloratadine 5 mg Versus Desloratadine 20 mg.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00536380 |
| Phase | Phase 4 |
| Condition | Chronic Idiopathic Urticaria |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 314 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Organon and Co |
| Results posted | Yes |
2. Clinical Question
Population
Participants had chronic idiopathic urticaria and were currently taking a second-generation antihistamine, according to the study summary. The primary outcome population is identified as the intent-to-treat population. The registry record does not provide further eligibility details in the information reported for this analysis, so the population should not be assumed to represent every person with chronic urticaria.
Intervention
The study assigned participants to once-daily desloratadine tablets at 5 mg, 10 mg, or 20 mg. Treatment was planned for 28 days. The stated research question concerned whether doses above 5 mg were associated with a different change in urticaria activity.
Comparator
The primary outcome title specifies a comparison of 5-mg and 20-mg desloratadine. The 10-mg group was also included in the trial, but the record does not report a numerical primary-outcome comparison involving that group in the information available for this analysis. The study descriptions list active desloratadine doses; they do not identify a placebo group.
Primary question
The primary endpoint was change in the Urticaria Activity Score (UAS) from baseline to the final treatment week for 5 mg versus 20 mg. The score combines diary-recorded wheal and pruritus ratings. The key statistical question is whether the average change differed between these dose groups and how precisely that difference was estimated. The registry record does not report the numerical estimate, its standard error, or a confidence interval, so the direction and precision of the primary comparison cannot be assessed from the record.
3. Trial Design
This was a completed, randomized, quadruple-masked, parallel-group phase 4 study sponsored by Organon and Co. The registry record reports enrollment of 314. That is the enrollment figure, not a statement of how many participants contributed data to the primary analysis. The record lists three treatment groups: desloratadine 5 mg once daily, 10 mg once daily, and 20 mg once daily.
The study began in 2007-09, and primary completion was recorded in 2009-04. The study summary says that participants with chronic urticaria who were taking a second-generation antihistamine would receive one of the desloratadine doses for 28 days. The primary endpoint timeframe is described as baseline and 4 treatment weeks, with the final week defined as the terminal week in which participants remained in the treatment period.
Randomization is intended to allocate treatment by chance, while masking is intended to limit the influence of treatment knowledge on conduct or assessment. The record identifies the masking level as quadruple but does not specify which roles were masked or how masking was maintained. A parallel-group design means the listed treatment groups are separate arms rather than treatment periods crossed within each participant. The registry record does not report the allocation ratio or further details of randomization procedures.
The primary endpoint title names a 5-mg versus 20-mg comparison. The 10-mg arm remains part of the study design, but no numerical primary outcome result for any contrast is reported in the registry record. The record also does not report a sample-size justification or enough information to determine how enrollment was divided among the arms or how many participants were included in each outcome analysis.
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
| Stage | 5-mg Desloratadine | 10-mg Desloratadine | 20-mg Desloratadine |
|---|---|---|---|
| STARTED | 106 | 104 | 104 |
| COMPLETED | 94 | 95 | 94 |
| NOT COMPLETED | 12 | 9 | 10 |
Reasons for not completing this period:
| Reason | 5-mg Desloratadine | 10-mg Desloratadine | 20-mg Desloratadine |
|---|---|---|---|
| Adverse Event | 0 | 2 | 2 |
| Lost to Follow-up | 0 | 0 | 1 |
| Withdrawal unrelated to study drug | 2 | 0 | 1 |
| Withdrawal related to study drug | 7 | 5 | 2 |
| Noncompliance with protocol | 3 | 2 | 2 |
| Did not meet protocol eligibility | 0 | 0 | 1 |
| Administrative | 0 | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: Intent to treat population
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.
| Characteristic | Unit | 5-mg Desloratadine | 10-mg Desloratadine | 20-mg Desloratadine | Total |
|---|---|---|---|---|---|
| Participants analysed | 106 | 104 | 104 | 314 | |
| Age, Continuous | years | 41.4 (SD 12.8) | 40.4 (SD 13.3) | 40.1 (SD 14.2) | 40.6 (SD 13.4) |
| Sex: Female, Male: Female | Participants | 70 | 69 | 70 | 209 |
| Sex: Female, Male: Male | Participants | 36 | 35 | 34 | 105 |
6. Primary Endpoint
The registry lists the primary outcome as Change in the Urticaria Activity Score (UAS) From Baseline to the Final Week for Desloratadine 5 mg Versus Desloratadine 20 mg, measured over Baseline and 4 treatment weeks.
| Element | Registry entry |
|---|---|
| Result type | Least Squares Mean |
| Measure of spread | Standard Error |
| Unit | Units on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change in the Urticaria Activity Score (UAS) from baseline to the final week of treatment, comparing desloratadine 5 mg with 20 mg. The registry describes the UAS as a composite of diary-recorded wheal and pruritus scores. Each symptom was rated for severity from 0 = none to 3 = intense. Participants recorded scores twice daily: within one hour of arising and in the evening, approximately 12 hours later. Each entry was reflective of the period since the preceding recording, and the daily UAS was the average of morning and evening scores.
Change from baseline is used to express how a measured score differs from its starting value during follow-up. Comparing changes between randomized groups can describe whether the average score trajectory differed across the assigned doses, rather than simply comparing final scores without reference to baseline. The final week was defined as the last week participants stayed in the treatment period, so the endpoint is tied to each participant’s terminal treatment week as described in the record.
The registry identifies the outcome summary as a least-squares mean with a standard error and names the intent-to-treat population. It does not report the numerical least-squares means, the between-group contrast, or its uncertainty. The record also gives no threshold for interpreting a particular UAS change as important to participants.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a primary comparison of change in UAS from baseline to the final treatment week between the 5-mg and 20-mg desloratadine groups. It describes the endpoint and the planned summary as a least-squares mean with a standard error, but does not report the numerical outcome estimate for either group or the between-group contrast. It also does not report a confidence interval or a p-value for that comparison. Consequently, the record does not establish the direction, size, or statistical precision of the primary outcome difference.
This absence matters for interpretation. An endpoint definition tells readers what was intended to be measured, but it cannot show how participants’ scores changed or whether the groups’ changes differed. Without the estimates and their uncertainty, it is not possible to distinguish a small, imprecisely estimated contrast from a larger, more precise one. Nor can the posted record support a claim about the relative UAS changes in the two dose groups. The existence of an outcome title alone is not a result.
The study included a 10-mg arm as well as the two doses named in the primary outcome. However, no numerical outcome results for that arm or any additional dose comparisons are reported in the information available in the registry record. It would be inappropriate to infer a dose pattern from the existence of the three assigned doses. The listed serious and other adverse event counts are separate safety summaries and cannot substitute for the missing primary efficacy estimate.
For context, the record reports enrollment of 314, but enrollment is not the same as the number analyzed for this endpoint. The primary population is labeled intent to treat, yet the record does not give analysis counts, missing outcome counts, or details of how missing observations were handled. The stated timeframe is baseline and 4 treatment weeks, and the summary describes a 28-day treatment period; neither detail supplies the missing outcome values.
The appropriate reading is therefore limited: the registry specifies a randomized comparison and a defined symptom-score endpoint, but the primary numerical result and its precision are not reported in the registry record. Any stronger conclusion about the comparative UAS changes would go beyond the posted results. This limitation applies to interpretation of the trial’s primary endpoint, not to the fact that the study was registered as completed.
9. Statistical Methods Explained
What does a least-squares mean represent?
The registry identifies the primary outcome parameter as a least-squares mean. General: a least-squares mean is an estimated group mean produced by a statistical model. It can differ from a simple arithmetic average when the model accounts for other terms or the structure of the data. The record does not describe the model, its covariates, or the exact calculation used, so those details are not reported in the registry record. The label alone does not reveal which adjustments, if any, were made.
For this endpoint, the quantity of interest is change in UAS from baseline to the final week. A group-specific mean change describes the estimated average change in that arm. A between-group contrast would then describe how the estimated change in one named group differs from the other. The record identifies the 5-mg versus 20-mg contrast in the endpoint title, but does not report the numerical group estimates or contrast. No value for the contrast should be inferred from the treatment assignments or study design.
What does the standard error tell readers?
The registry says the dispersion measure is a standard error. General: a standard error describes the sampling uncertainty of an estimate under the analysis used. A smaller standard error generally indicates greater precision for the estimate, while a larger one indicates less precision. It is not the same as the spread of individual participants’ scores. The record does not report the standard error value for the primary outcome, so the estimate’s precision cannot be judged from the stated parameter and dispersion labels alone.
General: a confidence interval combines an estimate with an expression of its uncertainty, giving a range of values compatible with the data under the interval’s assumptions. Its width is informative about precision. The registry record does not report a confidence interval for the primary contrast. Likewise, no p-value for the primary comparison is reported in the information. Without the estimate and uncertainty measures, statistical compatibility with different possible effects cannot be assessed.
Why does the endpoint use diary scores?
The UAS is built from repeated symptom recordings. The record says that wheal and pruritus were each rated from 0 = none to 3 = intense, with diary entries twice daily and a daily score formed by averaging the morning and evening scores. General: repeated measurements can capture symptom variation over time rather than relying only on a single retrospective measurement. They also create analysis choices about how daily observations are combined and how incomplete diaries are treated. The registry record does not describe those choices beyond the stated daily averaging and final-week definition.
The endpoint specifies baseline and the terminal treatment week. General: analyzing change relates follow-up measurements to each participant’s starting score. A model may account for baseline values or other design features, but the exact model cannot be assumed when it is not described. In this record, the use of a least-squares mean suggests a model-based summary, but the model specification is not reported in the registry record.
How should randomization and masking be understood?
The trial is identified as randomized and parallel-group. General: random assignment is intended to reduce systematic differences between treatment groups at the point of allocation, while a parallel design compares separate groups over the treatment period. Randomization does not guarantee identical groups on every characteristic, and it does not resolve missing-data or analysis concerns. The record does not report the allocation ratio or detailed sequence-generation and concealment procedures.
The masking level is recorded as quadruple. General: masking can reduce the influence of treatment knowledge on participant reporting, clinical management, or outcome assessment. The registry record does not identify which parties were masked, how masking was implemented, or whether it remained intact. No further inference about those procedures is justified from the label alone.
What can planning calculations say?
The study information describes sample-size assumptions as a planning illustration based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect, and that non-time-to-event planning figures represent participants per arm. These are assumptions for an illustrative planning exercise, not the trial’s own design justification. The registry record does not report the sponsor’s original sample-size rationale, and no planning result should be interpreted as observed power or as evidence that the trial was adequately or inadequately sized.
General: planning calculations depend on assumptions about the effect of interest, variability, significance level, allocation, and analysis. Changing those assumptions changes the planning result. They do not replace the observed treatment-effect estimate and its uncertainty. Because the primary outcome estimates and variability are not reported in the registry record, the comparative result cannot be reconstructed from the design description or planning assumptions.
10. Multiplicity, Missing Data and Analysis Populations
The record identifies a primary outcome title focused on UAS change for 5 mg versus 20 mg, and separately lists a 10-mg treatment group. It does not report a statistical analysis plan describing how multiple outcomes, comparisons, or time points were handled. The registry also notes that the primary outcome has several categories or time points and was not reduced to one comparison. That qualification limits any attempt to treat the title alone as a complete account of all outcome analyses or to infer a multiplicity adjustment.
General: when several hypotheses are tested, the chance of at least one apparently unusual result can increase if testing is not accounted for. Methods for handling multiplicity depend on the planned family of comparisons and the analysis strategy. The record does not report whether any adjustment was used, which comparisons were considered together, or whether a hierarchy of tests was specified. No particular approach should be presumed.
The primary population is described as intent to treat, but the record does not give the number of participants contributing primary outcome data, the quantity or pattern of missing observations, or the method used to handle missing data. General: missing-data methods can affect estimates if participants with incomplete measurements differ from those with complete measurements. The record does not establish why data may have been missing or how the analysis addressed it. It also does not report sensitivity analyses examining alternative missing-data assumptions.
These omissions mean readers cannot assess the full analysis population, the treatment of incomplete diaries, or the robustness of the reported primary comparison. Since the numerical primary result is not reported in the registry record, multiplicity and missing-data procedures cannot be connected to an observed estimate.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| 5-mg Desloratadine | 0 | 106 | 0.0% |
| 10-mg Desloratadine | 1 | 104 | 1.0% |
| 20-mg Desloratadine | 1 | 104 | 1.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| 5-mg Desloratadine | 5 of 106 |
| 10-mg Desloratadine | 4 of 104 |
| 20-mg Desloratadine | 6 of 104 |
Most frequent serious adverse event terms
| Event term | Organ system | 5-mg Desloratadine | 10-mg Desloratadine | 20-mg Desloratadine |
|---|---|---|---|---|
| Pneumonia | Infections and infestations | 0 of 106 | 1 of 104 | 0 of 104 |
| Urticaria | Skin and subcutaneous tissue disorders | 0 of 106 | 0 of 104 | 1 of 104 |
Most frequent non-serious adverse event terms
| Event term | Organ system | 5-mg Desloratadine | 10-mg Desloratadine | 20-mg Desloratadine |
|---|---|---|---|---|
| Headache | Nervous system disorders | 5 of 106 | 4 of 104 | 6 of 104 |
Serious events with the highest arm-level rate: pneumonia (1.0%), urticaria (1.0%).
The registry lists serious adverse event counts for the three desloratadine groups. In the 5-mg group, 0 serious adverse events were reported among 106 at risk. In the 10-mg group, 1 was reported among 104 at risk; in the 20-mg group, 1 was reported among 104 at risk. These are counts within the listed groups, not estimates of comparative risk, and no statistical comparison or uncertainty interval is reported.
The record also lists other adverse event counts: 5 among 106 at risk in the 5-mg group, 4 among 104 at risk in the 10-mg group, and 6 among 104 at risk in the 20-mg group. The registry’s top serious adverse event terms are Pneumonia at 1.0% and Urticaria at 1.0%. The record does not specify a group attribution for those terms in the information, so they should not be assigned to a particular dose group.
Deaths are not reported in the registry record. These counts do not establish that no other events occurred beyond those captured in the posted safety summaries, nor do they describe event severity beyond the serious-event classification. Small counts can be difficult to compare precisely, and the record does not provide enough information to assess differences in exposure duration or follow-up for safety.
12. What the Result Does, and Does Not, Mean
The trial record describes a randomized comparison of once-daily desloratadine doses in people with chronic idiopathic urticaria who were taking a second-generation antihistamine. It defines a symptom-based primary endpoint: change in UAS from baseline to the final treatment week, with a named comparison of 5 mg and 20 mg. This makes the research question and the intended measurement understandable.
However, the numerical primary outcome is not reported in the registry record. There is no reported group mean change, between-group estimate, standard error, confidence interval, or p-value in the information available for this analysis. As a result, the record does not show whether the UAS changes differed, in which direction they differed, or how precisely any difference was estimated. It cannot support a claim that one dose produced a larger or smaller change than another.
The presence of a 10-mg arm does not establish how outcomes varied across the three dose levels. The record’s safety counts are also not a substitute for the missing primary endpoint result. They are descriptive counts, with no reported comparative analysis or uncertainty measures. The listed serious adverse event terms do not have a dose-group attribution in the information.
General: a trial’s design, endpoint definition, and outcome estimates answer different questions. Design details describe how a comparison was intended to be conducted; outcome estimates show what was observed; uncertainty measures indicate how precisely those estimates were determined. In this record, the design and endpoint are described, but the numerical primary result is missing. It is therefore possible to explain what the study set out to compare, but not to evaluate its primary comparative finding from the registry record.
Nor does the enrollment figure establish the number analyzed, prove that all participants completed treatment, or show that the analysis had a particular degree of precision. The registry identifies the intent-to-treat population but does not provide analysis counts or missing-data details. The appropriate conclusion is limited to the documented study question and reported safety summaries, without a conclusion about comparative UAS change.
13. Why This Trial Matters Statistically
This trial illustrates why a clearly stated endpoint is necessary but not sufficient for statistical interpretation. The record describes the UAS as a composite of repeated wheal and pruritus ratings, explains how daily scores were formed, and defines the endpoint as change from baseline to the terminal treatment week. Those details help readers understand what the intended outcome represents and how it relates to the treatment period.
At the same time, a statistical comparison depends on the numerical estimates and their uncertainty. The record names least-squares means and standard errors but does not report their values or the contrast between the 5-mg and 20-mg groups. Readers therefore cannot assess the magnitude or precision of the primary comparison. This distinction is important: knowing the measurement and analysis labels does not reveal the observed result.
The record also offers a useful reminder to separate the three-dose design from the primary contrast named in the outcome title. The presence of 10-mg treatment does not by itself establish a dose-response pattern, and the record’s statement that the primary outcome has several categories or time points cautions against assuming that the title captures every analysis. Without a reported analysis plan, the handling of multiple comparisons cannot be judged.
Finally, the safety summaries show why counts need context. Serious and other adverse events are reported by group, but no comparative statistical assessment is reported, and deaths are not reported in the registry record. The counts can be described accurately while remaining cautious about what they establish. Overall, this record separates a well-defined study question from the missing numerical evidence needed to interpret its primary treatment comparison.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main limitation for interpreting efficacy is that the registry record does not report the primary outcome values or the between-group contrast. Although it identifies the endpoint, population, least-squares mean, and standard error, it provides no numerical estimate, confidence interval, or p-value for the primary comparison. This prevents assessment of direction, magnitude, and precision.
The record names an intent-to-treat population but does not report how many participants contributed primary outcome data, how many had incomplete diary measurements, or how missing values were handled. It does not describe the statistical model behind the least-squares mean, including any covariates or other adjustments. Randomization is reported, but allocation ratio and procedural details are not reported in the registry record. Quadruple masking is listed without identifying the masked roles or implementation details.
The primary outcome is described as having several categories or time points and not being reduced to one comparison. The record does not explain the multiplicity strategy or provide a statistical analysis plan, so the relationship between the named comparison and any other analyses is unclear. It also does not report a sample-size justification. The planning assumptions listed are illustrative and should not be read as evidence about the original design rationale or observed power.
For safety, the registry gives event counts and at-risk denominators, but no comparative estimates, uncertainty intervals, or detailed follow-up information. Deaths are not reported in the registry record, and the serious event terms are not attributed to specific groups in the information described. These reporting limits constrain interpretation of both efficacy and safety; they do not establish that unreported analyses or events did or did not occur.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Study for the Treatment of Chronic Idiopathic Urticaria With High Doses of AERIUS (Desloratadine) (Study P04849) — NCT00536380.
- Registry record last updated 2024-05-23; status last verified 2022-02.
- Results first posted 2010-05-03.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
This completed phase 4 study was randomized, quadruple-masked, and parallel-group, with enrollment of 314. It evaluated once-daily desloratadine at 5 mg, 10 mg, and 20 mg for chronic idiopathic urticaria. The study summary describes treatment for 28 days in participants taking a second-generation antihistamine.
The primary endpoint was change in UAS from baseline to the final treatment week, with the outcome title specifying 5 mg versus 20 mg and the intent-to-treat population. The registry describes the score’s diary components and identifies least-squares means with standard errors, but the numerical primary outcome result and its uncertainty are not reported in the registry record.
Serious and other adverse event counts are listed by dose group. The record does not report deaths or a comparative statistical safety analysis. The study design and measurement are documented, but the posted results do not permit interpretation of the primary comparative UAS change.