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 Sputum-derived Cellular Targets After Xolair (Omalizumab) (NCT02658877), a randomized phase 4 study. The primary outcome is Measurement in the Reduction of the Effect of Omalizumab on Thymic Stromal Lymphopoietin (TSLP) Using Two Group T-test in Moderate Persistent Asthma.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02658877 |
| Phase | Phase 4 |
| Condition | Asthma |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 3 |
| Arms in the primary outcome | n/a |
| Lead sponsor | NYU Langone Health |
| Results posted | Yes |
2. Clinical Question
Population
The registry identifies asthma and describes the primary outcome population as patients with moderate persistent asthma. It also states that most (n=124) patients failed screening criteria and the investigator did not move forward. Enrollment is listed as 3; further details about the characteristics of enrolled participants are not reported in the registry record.
Intervention
The active intervention was omalizumab. The registry describes a 16-week treatment period, but the dose, schedule, route, and other treatment details are not reported in the registry record.
Comparator
The comparator was placebo. The registry does not describe the placebo formulation or provide further details about how it was administered.
Primary question
The stated primary endpoint concerns measurement of the reduction in the effect of omalizumab on thymic stromal lymphopoietin (TSLP), using a two-group t-test in moderate persistent asthma. The record does not report a numerical endpoint result or a clear single comparison across the outcome's categories or time points.
3. Trial Design
This was a phase 4, randomized, double-masked, parallel trial comparing omalizumab with placebo in asthma. Randomization assigns participants to treatment groups by chance, while masking is intended to limit the influence of treatment knowledge on participants or study personnel. The registry does not identify which people were masked or describe the randomization procedure, allocation concealment, or how masking was maintained.
The listed enrollment is 3. The record also states that most (n=124) patients failed screening criteria and the investigator did not move forward. It does not explain the relationship between this screening statement and the enrollment figure, nor does it report detailed screening, enrollment, or retention flow. The number assigned to each intervention is not described in the main enrollment information; the safety data list 3 at risk for omalizumab and 0 for placebo.
The study began in 2016-01, reached primary completion on 2018-07-19, and has status TERMINATED. The reason for termination and whether termination occurred before or after any planned analyses are not reported in the registry record. The 16-week treatment period is stated for the primary endpoint, but the timing of assessments for other outcomes is not fully described.
The registry names omalizumab and placebo as the interventions, without arm-specific descriptions. It lists 11 outcome measures, including gene-expression-array assessment of sHBEC targets, change in Asthma Control Test score, change in lung function by spirometry, and change in small-airway dysfunction measures by impulse oscillometry. The record does not describe the planned allocation ratio, treatment doses, eligibility criteria in detail, or the rationale for the enrollment target.
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 | Omalizumab | Placebo |
|---|---|---|
| STARTED | 3 | 0 |
| COMPLETED | 3 | 0 |
| NOT COMPLETED | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Most (n=124) of these patients failed screening criteria and investigator did not move forward
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: None were on placebo because study had a block randomization of 6.
| Characteristic | Unit | Omalizumab | Placebo | Total |
|---|---|---|---|---|
| Participants analysed | 3 | 0 | 3 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 3 | 0 | 3 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 |
| Sex: Female, Male: Female | Participants | 2 | 0 | 2 |
| Sex: Female, Male: Male | Participants | 1 | 0 | 1 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): White | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 3 | 0 | 3 |
| Region of Enrollment: United States | Participants | 3 | 0 | 3 |
6. Primary Endpoint
The registry lists the primary outcome as Measurement in the Reduction of the Effect of Omalizumab on Thymic Stromal Lymphopoietin (TSLP) Using Two Group T-test in Moderate Persistent Asthma, measured over 16 Weeks of Treatment of omalizumab or placebo.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is described as measurement of the reduction in the effect of omalizumab on thymic stromal lymphopoietin (TSLP), using a two-group t-test in moderate persistent asthma. The stated timeframe is 16 Weeks of Treatment of omalizumab or placebo. TSLP is presented in the registry as a target of interest in a study concerned with cellular responses and mechanisms of action; the record does not give a biological assay description, measurement unit, scoring scale, or a more precise definition of what constitutes a reduction.
In general, a biomarker endpoint can help characterize biological changes associated with an intervention. A comparison between treatment groups can assess whether the measured marker differs between groups, while a change-from-baseline analysis can address how measurements shift over time. The registry wording does not make clear which exact contrast or summary measure was intended. It also does not report a baseline definition, the outcome's categories or time points, or a numerical result. Those omissions limit interpretation of what the primary endpoint represents in practice.
The registry identifies a two-group t-test as the method associated with the endpoint, but lists no analyses. Therefore, the stated method should not be taken as evidence that the test was carried out or that a treatment effect was estimated. The primary outcome is not reduced to one comparison in the posted record, and no endpoint result is reported.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes a randomized, double-masked comparison of omalizumab and placebo, but it does not report an analyzable primary outcome result. The primary endpoint is framed around TSLP over 16 weeks, yet its measurement scale and exact comparison are unclear, and the record does not provide a numerical estimate, confidence interval, or test result. Consequently, the posted information cannot establish the direction, size, or precision of a treatment-group difference for this endpoint.
The enrollment figure is 3, and the safety record lists 3 at risk in the omalizumab group and 0 at risk in the placebo group. The primary outcome population description also says most (n=124) patients failed screening criteria and the investigator did not move forward. The record does not clarify how this screening information relates to the enrolled or analyzed populations. This makes it especially important not to interpret the study as a balanced, completed comparison merely because the design is described as randomized and parallel.
The registry lists 11 outcome measures and 0 analyses. It identifies several secondary outcomes, including gene-expression-array assessment, asthma control, spirometry, and impulse oscillometry, but does not report results for them. The record also notes that the primary outcome has several categories or time points and was not reduced to one comparison. Without outcome estimates and their uncertainty, there is no basis for judging whether an observed difference is compatible with a range of effects or is precise enough to be informative.
In general, an estimate describes the observed contrast, while a confidence interval describes the uncertainty around that estimate under the analysis assumptions. Neither is reported for the primary endpoint in the registry information. A p-value alone, if one were reported, would not describe the size or practical importance of an effect; in this case, no primary p-value is listed either.
The status is TERMINATED, but the reason is not reported in the registry record. Termination by itself does not show why a trial stopped or what its results would have been if it had continued. The appropriate statistical reading is therefore limited: the record documents a study design, a small enrollment figure, and a stated biomarker question, but it does not provide outcome evidence from which to estimate an intervention effect.
9. Statistical Methods Explained
The registry associates a two-group t-test with the primary TSLP endpoint. This describes a planned or named method, not a confirmed analysis: the posted record lists 0 analyses and provides no test statistic, estimated difference, confidence interval, or p-value. The outcome is also flagged as having several categories or time points and not being reduced to one comparison, so a single test result cannot be reconstructed from the posted information.
What does a two-group t-test compare?
In general, a two-group t-test compares group means for a quantitative outcome. Its interpretation depends on the outcome definition, which participants contribute measurements, and whether the analysis compares follow-up values or changes from baseline. The registry does not specify the TSLP measurement scale, the summary used for analysis, or the precise contrast. It therefore does not support a numerical interpretation of a t-test for this trial.
General assumptions for a conventional t-test include independent observations and a suitable distributional approximation for the group means. A version that assumes equal variances also relies on a common within-group variance; other versions can allow unequal variances. The registry does not state which variant was intended, how assumptions would be checked, or whether any transformation or alternative method was planned. With an enrollment of 3 and no reported analysis population, assumptions cannot be evaluated from the registry record.
How should the stated result structure be understood?
The primary endpoint title refers to a reduction in the effect of omalizumab on TSLP, and the timeframe is 16 Weeks of Treatment of omalizumab or placebo. The description does not say whether the endpoint is a change from baseline, a follow-up measurement, or another summary. It also does not identify the categories or time points that prompted the registry's note that the endpoint was not reduced to one comparison. Without those definitions, a reader cannot determine which particular contrast the named test was meant to address.
In general, an effect estimate should be read alongside its uncertainty. A confidence interval gives a range of values compatible with the data and analysis assumptions; its width conveys precision. No effect estimate or confidence interval is reported for the primary endpoint. A p-value, if available, would address compatibility with a specified null model, but would not by itself show the magnitude or precision of an effect. No primary p-value is reported.
What does the sample-size illustration represent?
The record describes sample-size planning illustrations based on the observed effect, with a two-sided significance level of 0.05, equal allocation between groups, and a normal approximation. The illustration is described as considering an effect to detect at a stated fraction of the observed effect. No resulting sample-size values or observed-effect estimate are present in the registry information used for this interpretation. Such planning values are not observed power and do not establish that the trial was adequately sized. The registry does not report its own sample-size justification or design assumptions.
In general, planning calculations depend on the target effect, variability, significance level, power target, allocation, and analysis method. A calculation based on an observed effect is a planning illustration rather than evidence about what the trial actually detected. The absence of a reported endpoint estimate also prevents assessment of whether the illustration's reference effect is stable or precise.
What can be said about other analyses?
The registry lists 11 outcome measures and names secondary outcomes covering sHBEC targets measured by gene expression array, Asthma Control Test score, spirometry, and impulse oscillometry. It does not report analysis results for these outcomes. The record does not specify adjustment for baseline values, covariates, missing measurements, repeated observations, or multiplicity. Those choices can affect both the estimate and its uncertainty, so they should not be inferred from the outcome titles or the named t-test.
In general, repeated measurements or multiple endpoints can create several possible comparisons. A prespecified analysis plan clarifies which contrasts are primary and how uncertainty is handled across them. The registry record does not report such a plan, an interim-analysis approach, or analysis populations. Accordingly, no claim about an implemented statistical method beyond the method named for the primary endpoint is warranted.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 11 outcome measures, including the primary TSLP endpoint and secondary outcomes involving gene-expression-array targets, asthma control, spirometry, and impulse oscillometry. It also states that the primary outcome has several categories or time points and is not reduced to one comparison. When a study has multiple outcomes, time points, or possible contrasts, there can be more than one opportunity to find a result that appears unusual by chance. In general, a prespecified hierarchy or multiplicity adjustment can clarify how such results should be interpreted. No multiplicity procedure or testing hierarchy is reported in the registry record.
The record lists 0 analyses and does not report primary or secondary outcome estimates. It also does not describe the analysis population, missing-data methods, imputation, or how participants with incomplete measurements would be handled. These omissions mean that the available record cannot show whether the outcome data were complete or which participants contributed to any analysis.
The registry's statement that most (n=124) patients failed screening criteria and the investigator did not move forward is relevant to participant flow, but the record does not explain its relation to the enrollment figure of 3. It does not report the number screened, reasons for other exclusions, withdrawals, or follow-up completion in a way that resolves this relationship. The reason for termination and any planned interim analyses are not reported in the registry record. Thus, selection, missingness, and multiplicity cannot be evaluated from posted analysis results.
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 |
|---|---|---|---|
| Omalizumab | 0 | 3 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Omalizumab | 0 of 3 |
| Placebo | 0 of 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 |
|---|---|
| Omalizumab | 0 of 3 |
| Placebo | 0 of 0 |
The registry's safety figures list 3 participants at risk in the omalizumab group and 0 in the placebo group. For omalizumab, the record lists 0 serious adverse events, 0 other adverse events, and 0 deaths. For placebo, each of these counts is also listed as 0, but the placebo group has 0 participants at risk in the safety data. These figures should not be read as a comparative safety estimate between treatment groups.
In general, an event count is interpreted in relation to the participants observed and the period of observation. A group with no participants listed at risk does not provide a basis for estimating an event frequency in that group. Even when a group has participants listed, a count of zero in a small group cannot establish that an event cannot occur or precisely characterize its likelihood.
The registry does not provide event descriptions, exposure duration for safety reporting, or additional detail about how adverse events were collected. The figures describe what is entered in the safety record; they do not establish a broader safety conclusion.
12. What the Result Does, and Does Not, Mean
The registry documents a randomized, double-masked, parallel phase 4 trial of omalizumab and placebo for asthma, with a stated primary interest in TSLP over a 16-week treatment period. It also lists secondary outcomes related to cellular targets, asthma control, lung function, and small-airway dysfunction. These details establish the study's broad question and design, but do not constitute evidence of an outcome difference.
The posted record does not contain a numerical primary endpoint result, a reported analysis, or a clear single comparison for the primary outcome. It therefore cannot show the magnitude or direction of any difference between omalizumab and placebo, nor the precision of such a difference. The named two-group t-test does not imply that a test was conducted, particularly because the record lists 0 analyses.
The enrollment figure is 3, the study status is TERMINATED, and the safety record lists no placebo participants at risk. These details constrain interpretation but do not explain why the study ended or what results would have been found with a different enrollment or follow-up. The screening statement about most (n=124) patients failing criteria is not reconciled with the enrollment information.
In general, a trial's design and a treatment-effect result answer different questions. Randomization describes how assignment was intended to occur; an estimated contrast and its uncertainty are needed to assess observed outcomes. Neither the design label nor the stated biological rationale substitutes for those results. The record does not report a treatment effect, and the absence of one should not be translated into evidence of benefit, lack of benefit, or equivalence.
The record also does not report a sample-size justification, missing-data strategy, multiplicity plan, or reason for termination. These gaps leave substantial uncertainty about the intended and completed analyses. The defensible conclusion is that the registry identifies a mechanistic research question but does not provide an analyzable result with which to answer it.
13. Why This Trial Matters Statistically
This trial is statistically notable because its registry record places a mechanistic biomarker question alongside a randomized, double-masked design, yet does not provide a reported outcome comparison. That distinction matters: a design can describe how evidence was intended to be generated, but readers need outcome estimates and uncertainty to assess what the study observed.
The primary endpoint concerns TSLP and is associated with a two-group t-test, but its measurement scale and exact contrast are not specified. The record also notes several categories or time points and does not reduce the endpoint to one comparison. These details illustrate why a precise endpoint definition is essential: without it, a reader cannot tell what a single group comparison would represent or how to interpret an estimated difference.
The enrollment figure of 3 and the safety listing of 0 participants at risk for placebo further limit the interpretability of any between-group comparison. The record lists 0 analyses and gives no numerical endpoint results. There is therefore no basis for estimating effect size or precision. This is not the same as finding no effect; it is a lack of reported comparative results in the registry information.
The record's sample-size description also highlights a general distinction between planning and inference. Planning illustrations are not observed power and cannot substitute for actual estimates. Here, the registry does not report the illustration's numerical outputs, an observed-effect estimate, or its own sample-size justification. Together, these issues make the record useful primarily for understanding the intended question and the limitations of the available statistical reporting, rather than for quantifying an intervention effect.
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 registry record has important trial-specific limitations for statistical interpretation. It reports enrollment of 3 but does not explain the relationship between this figure and the statement that most (n=124) patients failed screening criteria and the investigator did not move forward. Participant flow, treatment-group assignment counts beyond the safety listing, and analysis populations are not reported in sufficient detail to reconcile these descriptions.
The study is marked TERMINATED, but the reason and timing relative to any planned analyses are not reported in the registry record. The primary endpoint lacks a clear measurement scale and a single defined comparison; its description field is blank, and the unit is not specified. Although a two-group t-test is named, the record lists 0 analyses and reports no estimate, confidence interval, or p-value.
The registry lists 11 outcome measures, but provides no outcome results in the information available for this analysis. It does not report a multiplicity strategy, missing-data methods, interim analyses, or the statistical analysis plan. The reason for termination, treatment dose and schedule, detailed arm descriptions, and detailed participant characteristics are also not reported in the registry record.
Safety interpretation is limited because the placebo group has 0 participants at risk in the safety listing. The recorded event counts therefore do not support a meaningful comparison between groups. These limitations prevent assessment of effect size, precision, robustness, and the extent to which the planned analyses were completed.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Sputum-derived Cellular Targets After Xolair (Omalizumab) — NCT02658877.
- Registry record last updated 2019-09-30; status last verified 2019-09.
- Results first posted 2019-09-30.
- 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.
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18. Record Summary
NCT02658877, titled “Sputum-derived Cellular Targets After Xolair (Omalizumab),” is a phase 4 randomized, double-masked, parallel trial sponsored by NYU Langone Health. It studied omalizumab and placebo in asthma. The listed enrollment is 3; the registry also notes that most (n=124) patients failed screening criteria and the investigator did not move forward.
The study began in 2016-01, reached primary completion on 2018-07-19, and is marked TERMINATED. Its primary endpoint concerns TSLP over 16 weeks and names a two-group t-test, but the primary outcome is not reduced to one comparison. The registry lists 11 outcome measures and 0 analyses. It does not report a numerical primary endpoint result, a reason for termination, or a complete statistical analysis plan.