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 Pomalidomide for Chronic Graft-versus-Host Disease (NCT01688466), a randomized phase 2 study. The primary outcome is Overall Response at 6 Months.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01688466 |
| Phase | Phase 2 |
| Condition | Graft vs Host Disease, Graft-Versus-Host Disease |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 34 |
| Arms in the primary outcome | n/a |
| Lead sponsor | National Cancer Institute (NCI) |
| Results posted | Yes |
2. Clinical Question
The study asks whether two dosing strategies for pomalidomide can be compared in people with chronic graft-versus-host disease that has not responded to standard treatments. Both study arms received pomalidomide; one strategy began at 0.5 mg/day and allowed dose escalation, while the other used 0.5 mg/day without escalation. The primary question was whether participants met the registry’s overall-response definition at 6 months.
Population
Adults with chronic graft-versus-host disease that had not responded to standard treatments. The registry lists 34 participants enrolled.
Intervention
Pomalidomide at 0.5 mg/day with dose escalation by 0.5 mg/day increments every 2 weeks to a maximum of 2.0 mg/day.
Comparator
Pomalidomide at 0.5 mg/day without dose escalation. This is an active dosing-strategy comparison, not a comparison with no treatment.
Primary question
How many participants in each strategy met the overall-response criteria at 6 months? The response categories are described, but the primary outcome result is not reported in the registry record.
The registry describes the trial as randomized, phase 2, parallel-group, and single-center. It also lists no masking. Those design features frame the comparison, but they do not by themselves establish what the primary outcome showed. The posted information does not report the allocation procedure beyond identifying the study as randomized, or provide a numerical comparison of response between the dosing strategies.
3. Trial Design
This was a randomized phase 2, single-center study with a parallel-group design and no masking. The registry lists 34 participants enrolled. The two arm descriptions distinguish pomalidomide dosing strategies: 0.5 mg/day with escalation in 0.5 mg/day increments every 2 weeks to a maximum of 2.0 mg/day, or 0.5 mg/day without escalation. Safety summaries list 17 participants at risk in each arm.
The registry’s study summary describes once-daily capsules given in 4-week cycles. The planned treatment period was six cycles, described as 6 months, unless disease worsened or side effects were too severe. Participants whose disease had improved at the end of that period might be able to continue for up to six more cycles. This description gives the intended treatment context; it does not establish how long each participant actually received treatment.
Screening and monitoring described in the study summary included physical examination, medical history, blood and urine samples, lung-function testing, and imaging. During treatment, the summary describes frequent blood tests and imaging, as well as saliva samples and skin and mouth tissue biopsies. The registry record does not report how consistently these assessments were completed.
The primary outcome was overall response at 6 months, assessed using National Institutes of Health chronic graft-versus-host disease response criteria. A secondary outcome concerned participants with serious and/or non-serious adverse events assessed under CTCAE v4.0. The record lists two outcome measures, but the primary response categories are not reduced to a single comparison in the posted results. The record does not report a sample-size justification, a detailed randomization procedure, or a statistical analysis plan.
The study is marked completed, with a start date of 2012-08-30 and a primary completion date of 2017-03-30. These dates describe the registry timeline and do not supply missing outcome estimates or explain the timing of individual participants’ assessments.
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 | 0.5 mg/Day With Dose Escalation | 0.5 mg/Day Without Dose Escalation |
|---|---|---|
| STARTED | 17 | 17 |
| COMPLETED | 15 | 10 |
| NOT COMPLETED | 2 | 7 |
Reasons for not completing this period:
| Reason | 0.5 mg/Day With Dose Escalation | 0.5 mg/Day Without Dose Escalation |
|---|---|---|
| Withdrawal by Subject | 2 | 1 |
| Death | 0 | 1 |
| Adverse Event | 0 | 4 |
| Not evaluable | 0 | 1 |
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 | 0.5 mg/Day With Dose Escalation | 0.5 mg/Day Without Dose Escalation | Total |
|---|---|---|---|---|
| Participants analysed | 17 | 17 | 34 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 16 | 14 | 30 |
| Age, Categorical: >=65 years | Participants | 1 | 3 | 4 |
| Age, Continuous | years | 48.5 (SD 14.2) | 46.8 (SD 13.9) | 47.65 (SD 14.05) |
| Sex: Female, Male: Female | Participants | 7 | 5 | 12 |
| Sex: Female, Male: Male | Participants | 10 | 12 | 22 |
| 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 | 1 | 0 | 1 |
| Race (NIH/OMB): White | Participants | 15 | 17 | 32 |
| Race (NIH/OMB): More than one race | Participants | 1 | 0 | 1 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Race/Ethnicity, Customized: Mexican, Puerto Rican, Cuban, Central/So. American | Participants | 0 | 2 | 2 |
| Race/Ethnicity, Customized: Not meeting definition for Hispanic or Latino | Participants | 17 | 15 | 32 |
| Region of Enrollment: United States | Participants | 17 | 1 | 18 |
6. Primary Endpoint
The registry lists the primary outcome as Overall Response at 6 Months, measured over 6 months.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants with an overall response at 6 months. Response was assessed using the NIH chronic graft-versus-host disease criteria. The categories distinguish complete response, partial response, response below partial response, stable disease, flare, progressive disease, and mixed response. Complete response requires resolution of signs and symptoms in affected organs or tissues. Partial response requires improvement in at least one organ or tissue without progression elsewhere. A change toward improvement that does not meet either response definition is classified below partial response. Stable disease means no change; flare and progressive disease have separate definitions, and mixed response is categorized as progressive disease.
This kind of endpoint is used to summarize clinical status across affected organs and tissues at a specified assessment time. It recognizes that changes can vary across disease sites, rather than treating improvement in one site as sufficient if another site worsens. The registry’s definitions therefore matter when interpreting any reported response count: the categories describe different states and are not interchangeable.
The posted record does not report the number of participants in each response category or a comparison between arms at 6 months. It also does not report how participants without an assessment were handled. Consequently, the endpoint’s definition can be explained, but the primary outcome result and its precision cannot be assessed from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry gives a clear description of the study question and the primary outcome, but it does not provide the primary response results. Although overall response at 6 months was the primary endpoint, the posted results do not state how many participants had complete response, partial response, response below partial response, stable disease, flare, or progressive disease in either arm. The record therefore does not support a numerical estimate of response or a conclusion about how the two dosing strategies compared on that endpoint.
The safety information is more detailed. Each arm’s safety summary lists 17 participants at risk. Serious adverse events affected 11 participants in the dose-escalation arm and 8 in the arm without escalation. Non-serious adverse events affected 17 participants in each arm. The record also lists serious adverse-event terms, including lung infection at 29.4%; carbon monoxide diffusing capacity decreased, dehydration, hypotension, skin infection, and wound infection are each listed at 11.8%. Deaths are listed as 0 in the dose-escalation arm and 1 in the arm without escalation.
These safety summaries are descriptive. They do not, on their own, establish that one dosing strategy caused more or fewer adverse events than the other. The record does not provide event-level timing, exposure-adjusted summaries, or a statistical comparison for these figures. The listed percentages should be read as registry summaries, not as a substitute for a full safety analysis. A participant with an event is not necessarily equivalent to an event count, since a participant may experience more than one event.
The study’s randomized design is relevant to how the comparison was intended to be made, but it does not fill in missing results. Interpretation also depends on how response was assessed, whether participants remained in their assigned groups for analysis, how missing assessments were handled, and whether any adjustment or prespecified testing strategy was used. Those details are not reported in the registry record.
The posted material therefore supports a limited reading: it identifies the population, two active dosing strategies, the response criteria and the reported safety summaries. It does not establish the size or precision of a difference in primary response. The completion status and enrollment total do not substitute for outcome estimates. The tables and plots on this page should be read alongside these gaps, with the distinction between descriptive safety data and an unreported primary efficacy comparison kept in view.
9. Statistical Methods Explained
What does the primary endpoint count? The primary measure is a participant count classified by overall response at 6 months. This is a categorical endpoint: each assessed participant is placed into a response category according to the registry’s NIH chronic graft-versus-host disease criteria. The categories convey different clinical patterns, including resolution, improvement, no change, flare, and progression. Because the record does not report a category-by-arm result, there is no posted primary response estimate to interpret.
Why do the categories matter? A composite response assessment can capture disease changes across multiple organs or tissues. The registry specifies that partial response involves improvement in at least one organ or tissue without progression in another affected site. It also states that mixed response, where some organs improve while others worsen, is categorized as progressive disease. These definitions determine how a participant’s overall status is classified. A different classification rule could change the meaning of a response summary, so the criteria should be considered part of the endpoint rather than as a technical footnote.
How should counts and percentages be read? A participant count reports how many people met a defined condition; a percentage expresses that count relative to a denominator. The registry’s safety summaries provide arm-specific numbers at risk and numbers affected, as well as percentages for selected serious-event terms. These are descriptive summaries. They do not supply a treatment-effect estimate, an uncertainty interval, or a formal comparison between arms. The record does not say whether the reported term percentages use a particular event-level or participant-level convention beyond the displayed safety information, so interpretation should remain close to the labels shown.
What does randomization contribute? In general, random assignment is intended to make comparison groups more similar at the start of a trial, on average, and can support a causal comparison when the analysis preserves the randomized groups and follow-up is adequately handled. This is a general statistical principle, not a finding about this trial’s balance or conduct. The registry identifies the study as randomized but does not report the allocation method, concealment procedures, baseline balance, or a detailed analysis population. The design label alone cannot confirm that all potential sources of bias were controlled.
What does masking mean? The record lists no masking. In general, masking can reduce the influence of treatment knowledge on outcome assessment or participant reporting, depending on who is masked and how an outcome is measured. Without masking, subjective assessments may be more vulnerable to expectations. The response endpoint uses defined criteria, which helps specify classification, but the registry does not report assessor masking or methods used to maintain consistency in assessment.
How should safety summaries be distinguished from event rates? The registry reports participants affected by serious and non-serious adverse events, and it identifies selected serious-event terms. Counts of participants affected are not necessarily counts of all events: one participant may have multiple events. General safety analysis may also consider severity, timing, duration, relatedness, and exposure time, but those details are not reported. No exposure-adjusted rates or inferential comparisons are given in the posted record.
What do confidence intervals and over-dispersion mean in general? A confidence interval is a range of values compatible with the data and a specified statistical procedure; it communicates uncertainty around an estimate. For a simple count-based model, over-dispersion means the observed variability is greater than the model expects. Accounting for it can widen uncertainty and change inference. These are general concepts. The registry record does not report a confidence interval or a count-model analysis for the primary endpoint, and the response categories are not presented as one numerical count comparison.
What are planning illustrations? A sample-size illustration can show, under stated assumptions, how many participants might be needed to detect a chosen effect with a chosen power and significance level. It is a planning exercise, not evidence that a trial had that power after completion. The planning framework is described as using a two-sided significance level of 0.05, equal allocation, a normal approximation, and an effect expressed as a fraction of the observed effect. Such illustrations do not replace the trial’s own design justification, which is not reported in the registry record. They also do not make an unreported primary result available or demonstrate observed power.
Why is a single comparison not shown for the primary endpoint? The registry outcome has several response categories, and the posted results are not reduced to one comparison. Collapsing categories would require a defined rule, such as selecting a particular contrast or grouping categories. Without such a rule and the underlying category counts, a reader should not infer a binary response result or calculate an effect estimate. The registry record does not report the analysis that would support such a reduction.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary response outcome and a secondary safety outcome, but it does not report a multiplicity strategy. Multiplicity arises when a study makes several statistical comparisons or tests multiple outcomes: the chance of at least one misleading positive result can increase if each is interpreted independently. In general, a prespecified testing hierarchy or adjustment can address that concern. The record does not report whether either approach was planned or used, so no claim about control of multiplicity is possible.
The primary response measure has several categories, but the posted results do not give the category counts or a single arm-to-arm comparison. The registry record does not report whether one category was designated as the main contrast for analysis, or whether any subgroup or secondary analyses were conducted. It also does not report inferential analyses for the listed outcomes. The absence of a posted comparison should not be read as evidence that no analysis occurred; the relevant analysis details are not reported in the registry record.
Missing data handling is also not reported in the registry record. For a response assessment at 6 months, interpretation can depend on whether participants who lack an assessment are excluded, treated as nonresponders, or handled using another method. The record does not state the number of missing assessments or the method used. The analysis population is not described: the registry does not state whether results were analyzed by randomized assignment, treatment received, or another definition.
These omissions limit assessment of bias and uncertainty. They prevent readers from determining how incomplete follow-up affected the endpoint, which participants contributed to any analysis, or how multiple outcomes and comparisons were interpreted. They do not justify assuming that a particular method was used.
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 |
|---|---|---|---|
| 0.5 mg/Day With Dose Escalation | 11 | 17 | 64.7% |
| 0.5 mg/Day Without Dose Escalation | 8 | 17 | 47.1% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| 0.5 mg/Day With Dose Escalation | 0 of 17 |
| 0.5 mg/Day Without Dose Escalation | 1 of 17 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| 0.5 mg/Day With Dose Escalation | 17 of 17 |
| 0.5 mg/Day Without Dose Escalation | 17 of 17 |
Most frequent serious adverse event terms
| Event term | Organ system | 0.5 mg/Day With Dose Escalation | 0.5 mg/Day Without Dose Escalation |
|---|---|---|---|
| Lung infection | Infections and infestations | 2 of 17 | 5 of 17 |
| Hypotension | Vascular disorders | 1 of 17 | 2 of 17 |
| Skin infection | Infections and infestations | 1 of 17 | 2 of 17 |
| Bronchial infection | Infections and infestations | 1 of 17 | 1 of 17 |
| Carbon monoxide diffusing capacity decreased | Investigations | 2 of 17 | 0 of 17 |
| Dehydration | Metabolism and nutrition disorders | 0 of 17 | 2 of 17 |
| Hypoxia | Respiratory, thoracic and mediastinal disorders | 1 of 17 | 1 of 17 |
| Wound infection | Infections and infestations | 0 of 17 | 2 of 17 |
| Acute kidney injury | Renal and urinary disorders | 0 of 17 | 1 of 17 |
| Alanine aminotransferase increased | Investigations | 1 of 17 | 0 of 17 |
Most frequent non-serious adverse event terms
| Event term | Organ system | 0.5 mg/Day With Dose Escalation | 0.5 mg/Day Without Dose Escalation |
|---|---|---|---|
| Lymphocyte count decreased | Investigations | 10 of 17 | 8 of 17 |
| Upper respiratory infection | Respiratory, thoracic and mediastinal disorders | 7 of 17 | 9 of 17 |
| Fatigue | General disorders | 10 of 17 | 3 of 17 |
| Hypophosphatemia | Metabolism and nutrition disorders | 9 of 17 | 4 of 17 |
| Rash maculo-papular | Skin and subcutaneous tissue disorders | 5 of 17 | 5 of 17 |
| Neutrophil count decreased | Investigations | 6 of 17 | 2 of 17 |
| Edema limbs | General disorders | 3 of 17 | 4 of 17 |
| Lung infection | Infections and infestations | 4 of 17 | 3 of 17 |
| Diarrhea | Gastrointestinal disorders | 4 of 17 | 2 of 17 |
| Tremor | Nervous system disorders | 5 of 17 | 1 of 17 |
Serious events with the highest arm-level rate: lung infection (29.4%), carbon monoxide diffusing capacity decreased (11.8%), dehydration (11.8%), hypotension (11.8%), skin infection (11.8%).
The posted safety summaries use 17 participants at risk in each arm. Serious adverse events affected 11 participants in the 0.5 mg/day arm with dose escalation and 8 participants in the 0.5 mg/day arm without dose escalation. Non-serious adverse events affected 17 participants in each arm. The registry lists deaths as 0 in the escalation arm and 1 in the arm without escalation.
The selected serious-event terms include lung infection at 29.4%. Carbon monoxide diffusing capacity decreased, dehydration, hypotension, skin infection, and wound infection are each listed at 11.8%. These entries describe the terms and percentages shown in the registry. They should not be added together: the record does not establish that the terms occurred in mutually exclusive participants, and a participant can experience more than one adverse event.
These figures are descriptive, not a statistical comparison. The registry does not provide uncertainty intervals, a hypothesis test, event timing, or exposure-adjusted rates for these summaries. The counts therefore do not establish that either dosing strategy had a higher or lower safety risk. Serious and non-serious event summaries also do not, by themselves, describe severity gradations, duration, or attribution to treatment.
12. What the Result Does, and Does Not, Mean
This trial record is useful for understanding the question researchers set out to study: a randomized comparison of two pomalidomide dosing strategies in chronic graft-versus-host disease, with overall response at 6 months as the primary endpoint. It also provides the response definitions and descriptive safety summaries. Those elements help readers understand what was to be measured and what kinds of safety information were posted.
The primary response result is not reported in the registry record. There is no arm-specific response count, effect estimate, or confidence interval in the posted information. Consequently, the record cannot show how precisely the two strategies differed on the primary endpoint. The study’s completion status and enrollment total are not evidence of a particular response outcome.
The safety summaries show participants affected by serious and non-serious adverse events, selected serious-event terms, and deaths by arm. They do not establish a causal difference between dosing strategies. The summary does not include the detail needed to assess timing, treatment exposure, repeated events, or statistical uncertainty. A descriptive contrast between the listed arm summaries is not the same as a prespecified comparative analysis.
In general, a trial’s result must be interpreted in light of its design, outcome definition, missing data, analysis population, and statistical plan. Several of these details are not reported in the registry record. The information available supports a description of the study design and posted safety figures, but not a conclusion about efficacy or a precise comparative treatment effect. This is a statistical reading of the posted record, not medical advice.
13. Why This Trial Matters Statistically
This study illustrates why a trial’s endpoint definition and its posted result need to be considered together. The primary endpoint is not simply an unspecified judgment of improvement: the registry describes categories for complete response, partial response, response below partial response, stable disease, flare, and progressive disease, including how mixed changes are classified. Those rules shape the meaning of any response summary.
It also demonstrates a common challenge in registry-based interpretation. A record can identify the design and endpoint while not presenting the outcome counts or a comparative estimate needed to answer the main statistical question. Here, the record describes a randomized, parallel-group comparison of two active dosing strategies, but does not report the primary response categories by arm. A reader should distinguish a stated objective from a reported result.
The safety data offer another statistical lesson: counts of participants affected, event terms, and percentages are descriptive quantities, not automatically comparative estimates. Participants may experience multiple events, and the registry does not provide timing or exposure-adjusted summaries. Those limitations matter when interpreting apparent differences between arm summaries.
Finally, the record highlights the importance of transparent information on missing data, analysis populations, multiplicity, and the statistical plan. Such details help readers understand what evidence an estimate represents and how uncertainty was handled. Their absence does not establish that no methods were used, but it limits independent assessment of the posted results. The trial is statistically informative as an example of how much a registry record can describe—and where incomplete reporting constrains interpretation.
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 this trial is that the registry record does not report the primary outcome result by arm. Although overall response at 6 months is defined in detail, the posted information does not give category counts, an overall comparison, or an estimate with uncertainty. This prevents assessment of the primary endpoint’s direction, magnitude, or precision.
The registry does not report the sample-size justification or the statistical analysis plan. It also does not describe the randomization procedure beyond identifying the study as randomized, or report allocation concealment, baseline balance, or the analysis population. The handling and amount of missing six-month response data are not reported. These gaps limit assessment of how the study was designed to answer its question and how participants contributed to any analysis.
The safety summaries are also limited. They identify participants affected and selected serious-event terms, but do not provide event timing, duration, attribution, exposure-adjusted rates, or uncertainty intervals. The record does not explain whether the listed event percentages represent participants or events beyond the displayed summaries. As a result, the figures are best treated as descriptive and cannot establish a comparative safety effect.
The study is identified as single-center and unmasked. These are features of the recorded design, not proof of a particular bias, but they are relevant context when considering how broadly findings might apply and how outcomes may have been assessed. The registry does not provide enough information to evaluate these issues in detail. Finally, because the primary response outcome is not reduced to one comparison in the posted results, no single effect estimate can be interpreted from the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Pomalidomide for Chronic Graft-versus-Host Disease — NCT01688466.
- Registry record last updated 2025-10-08; status last verified 2025-09.
- Results first posted 2018-01-23.
- 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
The registry describes NCT01688466, titled “Pomalidomide for Chronic Graft-versus-Host Disease,” as a completed, randomized phase 2, single-center, parallel-group study with no masking. It lists 34 participants enrolled. The two arms compare pomalidomide at 0.5 mg/day with dose escalation and 0.5 mg/day without dose escalation.
The primary outcome is overall response at 6 months under NIH chronic graft-versus-host disease response criteria. The registry also lists a secondary safety outcome. The primary response result is not reported in the registry record. Safety summaries list 17 participants at risk per arm, along with serious and non-serious adverse-event information and deaths.
The recorded study start date is 2012-08-30, and the primary completion date is 2017-03-30. The posted information describes the trial question, endpoint definitions, and selected safety findings, but does not provide the primary response comparison or key analysis details such as missing-data handling, the analysis population, and the statistical plan.