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 Phase II Study of Adenovirus/PSA Vaccine in Men With Hormone - Refractory Prostate Cancer (NCT00583024), a na phase 2 study. The primary outcome is Number of Participants With Stable, Decreased, or Increased PSA Doubling Times (PSADT).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00583024 |
| Phase | Phase 2 |
| Condition | Hormone Refractory Prostate Cancer |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 32 |
| Arms in the primary outcome | n/a |
| Lead sponsor | David M Lubaroff |
| Results posted | Yes |
2. Clinical Question
Population
Men with hormone-refractory prostate cancer. The study description specifies metastatic disease with evidence of hormone-refractory status; the registry record does not give further eligibility details in the information reported for this study.
Intervention
An adenovirus/PSA vaccine administered as three subcutaneous injections. The arm description specifies 0.16 ml for each injection, consisting of 0.125 ml vaccine and 0.035 ml Gelfoam.
Comparator
There is no concurrent comparator group in this single-group study. The record lists allocation as NA and masking as none, so the design does not provide a randomized, masked comparison of the vaccine with another treatment or control.
Primary question
The primary outcome asks how many participants had stable, decreased, or increased PSA doubling times during the 18 months specified for the outcome. The registry describes evaluating PSA responses and changes in PSADT using a prime-boost immunization strategy, with PSADT calculated using the MSKCC online calculator. The observed counts for the response categories are not reported in the registry record.
This question is descriptive as recorded: it concerns the distribution of participants across PSA doubling-time response categories after vaccination. It is not framed as a comparison against an untreated group or another therapy. Consequently, even if the category counts were available, they would describe outcomes among participants in this study rather than directly estimate a difference between treatments. The registry also lists the number of participants alive and deceased following treatment as a secondary outcome. The results for that outcome are not reported in the registry record in the information available for this analysis.
3. Trial Design
The registry identifies this study as Phase II and describes it as a single-group trial of an adenovirus/PSA vaccine in men with hormone-refractory prostate cancer. The recorded enrollment is 32. The study began in 2007-12, its primary completion date is 2020-12-31, and its status is completed. These administrative details describe the record, but they do not supply the outcome results needed to assess the primary question.
Participants were assigned to the Adenovirus/PSA Vaccine arm. Its description specifies three subcutaneous injections of 0.16 ml, with each injection described as 0.125 ml vaccine plus 0.035 ml Gelfoam. Allocation is recorded as NA, masking as none, and the model as single-group. There is therefore no separate randomized control arm in the design described by the registry. The record does not report a protocol-defined comparison group or a masked assessment procedure.
The primary outcome is the number of participants with stable, decreased, or increased PSA doubling times, with an 18-month timeframe. The outcome description says that the study evaluates PSA responses and changes in PSADT using a prime-boost immunization strategy, and that PSADT is calculated using the MSKCC online calculator. The registry also lists a secondary outcome concerning participants alive and deceased following treatment. Detailed analysis results for these outcomes are not reported in the registry record.
The registry lists three outcome measures, but the analysis information records zero analyses. A completed study status should not be confused with a complete report of efficacy or safety results. The registry record does not report the statistical analysis plan, sample-size justification, analysis populations, or whether any interim analyses were planned or conducted. Those details should not be inferred from the Phase II label or from the enrollment entry.
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 | Adenovirus/PSA Vaccine |
|---|---|
| STARTED | 32 |
| COMPLETED | 28 |
| NOT COMPLETED | 4 |
Reasons for not completing this period:
| Reason | Adenovirus/PSA Vaccine |
|---|---|
| Lost to Follow-up | 4 |
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 | Adenovirus/PSA Vaccine |
|---|---|---|
| Participants analysed | 32 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 6 |
| Age, Categorical: >=65 years | Participants | 26 |
| Sex: Female, Male: Female | Participants | 0 |
| Sex: Female, Male: Male | Participants | 32 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 31 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 32 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 32 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants With Stable, Decreased, or Increased PSA Doubling Times (PSADT), measured over 18 months.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is a participant count grouped by the direction of change in PSA doubling time: stable, decreased, or increased. The stated timeframe is 18 months. PSADT refers to the time taken for PSA to double, and the registry says it is calculated with the MSKCC online calculator. The endpoint therefore turns a continuous measure of timing into categories describing the direction of change. The registry’s outcome description also refers more broadly to evaluating PSA responses and changes in PSADT under a prime-boost immunization strategy.
As a general statistical point, a categorized endpoint can make a result easier to describe in terms of how many participants fall into each response group. However, categorization can conceal variation within a category: participants assigned the same label may have different underlying PSADT values or different magnitudes of change. A participant count also does not by itself show the size or precision of a change in PSADT. Those questions would require the actual outcome data and, for a comparison, an appropriate reference group or baseline-based analysis.
The registry record does not report the counts in the stable, decreased, and increased categories, nor does it provide an effect estimate or confidence interval for this primary endpoint. Thus, the endpoint can be identified and explained, but its observed distribution cannot be described from the reported results.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes a completed Phase II study with a single group receiving the adenovirus/PSA vaccine. The primary outcome is a count of participants with stable, decreased, or increased PSA doubling times over the stated 18 months. The record identifies this endpoint and its calculation approach, but the category counts are not reported in the registry record. As a result, the central descriptive result cannot be stated, and the direction or size of any observed change cannot be assessed from the information reported.
The distinction between a defined endpoint and a reported result is important. A registry entry can specify what investigators intended to measure without presenting the resulting measurements. Here, the endpoint description does not give the number of participants in each response category, the distribution of PSADT values, or a measure of uncertainty. The record also lists three outcome measures and zero analyses. Those entries do not establish what analyses were planned, whether analyses were performed outside the registry, or why detailed results are absent; those explanations are not reported in the registry record.
The design places a further limit on interpretation. Because the study is single-group, it has no concurrent control group against which to estimate a treatment contrast. Any observed changes in a group over time would be descriptive unless interpreted through a suitable comparison or other explicitly stated analytic framework. The registry record does not report such a comparative estimate or an analysis plan. The absence of a randomized comparator also means the design, as recorded, cannot separate changes associated with receiving the vaccine from changes that might occur over time for other reasons.
Precision cannot be evaluated for the primary endpoint because no category counts, effect estimates, or confidence intervals are reported. A confidence interval, as a general statistical concept, expresses the uncertainty associated with an estimate under the assumptions of the analysis. Without an estimate and its uncertainty measure, readers cannot judge whether a result is narrowly or broadly determined. No p-value for the primary endpoint is reported in the registry record.
The record does provide adverse-event figures for the vaccine group, including 32 participants at risk, 3 affected by serious adverse events, 18 affected by other adverse events, and 21 deaths. It also lists several serious-event terms with percentages. These entries describe what the registry records, but they do not establish that an event was caused by the vaccine. The record does not provide the detail needed to assess timing, duration, attribution, or comparisons with a control group.
Overall, the registry establishes the study question, the single-group design, the intervention description, and selected safety counts. It does not report enough primary outcome results or analytic detail to support a numerical assessment of the PSA doubling-time response pattern or its precision.
9. Statistical Methods Explained
Statistical interpretation begins by identifying the question the design can answer. This study is recorded as a single-group Phase II trial, with allocation listed as NA and masking as none. The primary endpoint is a count of participants classified by whether PSA doubling time was stable, decreased, or increased during the stated 18 months. Because there is no concurrent comparator group in the recorded design, the endpoint is not a randomized estimate of a difference between treatments. The registry record does not report a separate comparative analysis.
What does a participant count describe?
A count reports how many participants meet a defined category. When categories are mutually exclusive and cover all participants in the analysis, their counts can describe the observed distribution. Whether the categories in this study are exhaustive for the analyzed population, how missing measurements were handled, and what population was included in the endpoint analysis are not reported in the registry record. Without the category counts, even the descriptive distribution cannot be reconstructed.
A count is also different from an effect estimate. A count alone does not express how much PSADT changed, how much variation existed between participants, or how uncertain an estimated response rate might be. As a general statistical explanation, an estimate of a proportion or a mean is often paired with an interval to convey uncertainty. No such interval or primary endpoint estimate is reported in the registry record. No numerical result should therefore be inferred from the endpoint title or from the overall enrollment entry.
Why does the single-group design matter?
In a comparative trial, the treatment effect is commonly framed as a contrast between outcomes under different assigned groups. A single-group study does not supply that concurrent contrast. Describing outcomes after treatment can still be informative about what was recorded among participants, but it does not, by itself, establish what would have happened to comparable participants without the intervention or under another intervention. This is a general limitation of interpreting change over time without a concurrent control, not a claim about what happened to participants in this study.
Random allocation, when used, is intended to make treatment groups comparable on average with respect to both measured and unmeasured factors. This record does not describe randomized allocation and lists a single group. The registry record does not report a protocol-defined external comparator or an adjustment strategy that could support a treatment contrast. Masking is recorded as none; details about outcome assessment procedures beyond the PSADT calculator description are not reported in the registry record.
How should PSADT be understood?
The registry says that PSADT will be calculated using the MSKCC online calculator. It defines the primary outcome by categories of change in PSADT, but does not report the calculation inputs, the timing of measurements, rules for selecting measurements, or the threshold used to define a stable response. Those details are not reported in the registry record. They matter because calculated values can depend on the measurements and rules used, while categorization depends on prespecified criteria. Readers should not assume a specific threshold or calculation procedure beyond the description actually recorded.
As a general statistical point, converting a continuous measurement into categories simplifies communication but discards information about the size of changes and differences among participants. It can also make results sensitive to the boundaries chosen for the categories. A fuller account would ordinarily clarify those boundaries and report the underlying measurement or an analysis that retains its continuous information. Such details and results are not reported in the registry record, so the primary endpoint can be described only at the level of its stated categories.
What do confidence intervals and p-values add?
General explanation: a confidence interval describes the range of values compatible with an estimate under a specified statistical procedure and its assumptions. It helps readers evaluate precision, but it does not correct a weak design or remove bias. A p-value addresses how incompatible data are with a specified null model, given the analysis assumptions; it does not directly measure the probability that a treatment works or the size of an effect. Neither a primary endpoint confidence interval nor a p-value is reported in the registry record. In their absence, the statistical uncertainty around the endpoint cannot be assessed from this record.
The record lists zero analyses. This does not establish whether analyses were performed elsewhere or whether the registry entry is incomplete. The analysis plan, including any covariate adjustment, handling of repeated measurements, or approach to multiple outcomes, is not reported in the registry record. Any interpretation requiring those details would be speculative.
What can planning calculations say?
General explanation: sample-size planning uses assumptions about the expected effect, variability, significance criterion, allocation, and analysis method to illustrate how much information a future study might need. A planning illustration is not an observed result and is not observed power. The registry record does not report the trial’s sample-size justification or statistical design assumptions. Nor does it report the primary endpoint result needed to interpret calculations based on an observed effect. Therefore, a planning number should not be treated as a finding about the participants in this trial or as evidence that the study was adequately powered.
For count outcomes, the statistical model should match the nature of the data and the way observations were collected. General explanation: over-dispersion occurs when the observed variability is greater than a model expects; ignoring it can make uncertainty appear too small. The registry record does not report a model, dispersion estimate, or model-based analysis for the primary endpoint. Since the endpoint results and analyses are not reported, no model assumptions can be checked against the observed data.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists three outcome measures, including the primary PSA doubling-time outcome and a secondary outcome concerning the number of participants alive and deceased following treatment. The analysis record lists zero analyses. The registry record does not report a statistical analysis plan, the status of each outcome, or whether any additional outcomes were analyzed. It also does not describe how the investigators handled the possibility of multiple outcomes or multiple statistical tests.
As a general statistical principle, examining several outcomes or several versions of an analysis can increase the chance of a seemingly noteworthy result arising by chance. A prespecified hierarchy or multiplicity adjustment can address some of that issue, but the methods used in this study are not reported in the registry record. It would be inappropriate to assume either that multiplicity was addressed or that it was ignored.
The registry record does not report how missing PSA measurements or missing endpoint data were handled. It does not identify the analysis population for the primary endpoint, describe exclusions, or say whether all participants with recorded enrollment contributed to the endpoint analysis. These omissions matter because a count of response categories depends on which participants have usable measurements and on the rules for assigning categories when data are incomplete. No missing-data method or sensitivity analysis is reported in the registry record.
The recorded enrollment is 32, but the primary outcome counts are not reported. Enrollment alone does not establish the denominator used for the endpoint analysis. The record does not report whether the analysis followed an intention-to-treat principle, used a treated-participant population, or applied another population definition. Those details should not be inferred from the single-group design or the completion status.
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 |
|---|---|---|---|
| Adenovirus/PSA Vaccine | 3 | 32 | 9.4% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Adenovirus/PSA Vaccine | 21 of 32 |
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 |
|---|---|
| Adenovirus/PSA Vaccine | 18 of 32 |
Most frequent serious adverse event terms
| Event term | Organ system | Adenovirus/PSA Vaccine |
|---|---|---|
| Pulmonary emboli | Respiratory, thoracic and mediastinal disorders | 1 of 32 |
| Obstruction/stenosis of airway - Bronchus | Respiratory, thoracic and mediastinal disorders | 1 of 32 |
| Cardiac ischemia/infarction | Cardiac disorders | 1 of 32 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Adenovirus/PSA Vaccine |
|---|---|---|
| Cold and flu symptoms | General disorders | 5 of 32 |
| Headache | General disorders | 4 of 32 |
| Injection site irritation | Skin and subcutaneous tissue disorders | 4 of 32 |
| Fatigue | General disorders | 3 of 32 |
| Flushing | Skin and subcutaneous tissue disorders | 1 of 32 |
| Myalgia | Musculoskeletal and connective tissue disorders | 1 of 32 |
Serious events with the highest arm-level rate: pulmonary emboli (3.1%), obstruction/stenosis of airway - bronchus (3.1%), cardiac ischemia/infarction (3.1%).
The adverse-event record lists the Adenovirus/PSA Vaccine group with 32 participants at risk for serious adverse events and 3 affected. It also lists 32 at risk for other adverse events and 18 affected, along with 21 deaths. These are registry counts, not treatment-effect estimates. The record lists Pulmonary emboli, Obstruction/stenosis of airway - Bronchus, and Cardiac ischemia/infarction among the top serious-event terms, each with a reported percentage of 3.1%.
These figures should be read as descriptive entries for the study group. The registry record does not provide a concurrent control group, so these counts cannot be used to estimate whether the event frequency was higher or lower than it would have been under another treatment or without treatment. The listed terms and percentages also do not establish that the vaccine caused any event.
The record does not report event timing, duration, severity grading beyond the serious-event classification, attribution, recurrence, or the follow-up period associated with each safety count. The relationship between the death count and specific causes is not reported in the registry record. Counts of participants affected also do not necessarily convey the total number of event episodes. These limitations make the figures useful as a record of reported safety information, but insufficient for causal conclusions or a complete account of individual safety histories.
12. What the Result Does, and Does Not, Mean
The registry record establishes that this was a completed Phase II, single-group study of an adenovirus/PSA vaccine in men with hormone-refractory prostate cancer. It describes the intervention, identifies PSA doubling-time response categories as the primary endpoint, and states that PSADT was to be calculated using the MSKCC online calculator. The endpoint timeframe is 18 months. The record also contains adverse-event counts and identifies a secondary outcome concerning participants alive and deceased following treatment.
What the record does not establish is the observed primary endpoint result. The numbers of participants with stable, decreased, or increased PSADT are not reported in the registry record, and no effect estimate, confidence interval, or p-value for that endpoint is reported. The secondary outcome results are also not reported in the registry record. Consequently, the endpoint’s response pattern and statistical precision cannot be assessed from the results recorded.
The single-group design also limits what can be concluded. Without a concurrent comparator, the registry’s design does not provide a randomized estimate of how outcomes differ between the vaccine and another treatment or control. This does not negate the descriptive role of a single-group study; it defines the scope of its evidence. A change observed in a group cannot, by itself, isolate the effect of the intervention from other influences.
The safety entries provide counts and listed event terms, but do not determine causality. The registry record does not report the attribution and timing details needed to interpret the events in that way. The study’s completed status likewise does not fill in missing results or analytic methods. The practical statistical reading is therefore bounded: the record documents a study question and design, but leaves the primary outcome results and important analysis details unreported.
13. Why This Trial Matters Statistically
This study is statistically informative as an example of why a registry record’s design, outcome definition, and reported results must be considered separately. The record specifies a concrete primary endpoint: participant counts across stable, decreased, and increased PSA doubling-time categories. It also states an 18-month timeframe and identifies the calculator used for PSADT. Those details clarify what was intended to be measured, even though the outcome counts are not reported in the registry record.
The single-group design is central to interpreting the question. It permits a description of participants’ recorded outcomes, but does not supply a concurrent randomized contrast. A reader should not treat the intervention group’s course as if it were a comparison between treatments. In general, the lack of a comparator limits causal interpretation, while the absence of reported primary outcome results prevents even a complete descriptive account of the stated endpoint.
The record also illustrates why precision and analysis transparency matter. Without category counts, estimates, confidence intervals, or a reported analysis, there is no basis for judging how uncertain the primary result is. Without information on analysis populations and missing data, readers cannot determine which participants contributed to the endpoint or how incomplete observations were addressed. These are not merely technical details: they affect the meaning and reliability of an outcome summary.
For clinical researchers and biostatisticians, the key lesson is to distinguish what a trial was designed to measure from what its registry record reports as observed. A named endpoint, a completed status, and an enrollment entry do not substitute for outcome estimates and methods. The available safety counts are similarly descriptive and do not establish causation. Clear reporting of results, denominators, analysis populations, uncertainty, and analytic choices is necessary for readers to evaluate evidence within the limits of the study design.
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 most direct limitation is that the primary endpoint is defined but its observed category counts are not reported in the registry record. The record therefore does not show how many participants had stable, decreased, or increased PSA doubling times. It also does not report an effect estimate, a measure of uncertainty, or a p-value for that endpoint. The absence of these results prevents a direct statistical assessment of the primary question.
The single-group design has no concurrent control arm, and allocation is listed as NA. Masking is recorded as none. These design features limit comparative and causal interpretation. The registry record does not describe a separate comparator or an alternative method for estimating a treatment contrast.
Important endpoint details are not reported in the registry record. Although the outcome description names the MSKCC online calculator and the response categories, it does not give the operational criteria for stable, decreased, or increased PSADT, the measurement schedule, or the handling of incomplete measurements. The analysis population and missing-data methods are also not reported. The record lists three outcome measures and zero analyses, but does not explain the analysis plan or the status of each outcome.
The safety information is also limited in interpretability. The record lists counts of participants affected and selected event terms, but does not report event timing, attribution, duration, or a control-group comparison. The reported death count is not accompanied by cause-specific information in the registry record. These limitations mean that the safety entries should be treated as descriptive rather than as evidence of causal relationships.
Finally, the registry record does not report the trial’s sample-size justification, interim-analysis plans, or detailed statistical methods. These gaps should not be filled by assumptions based on the Phase II designation, enrollment, or completed status.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Phase II Study of Adenovirus/PSA Vaccine in Men With Hormone - Refractory Prostate Cancer — NCT00583024.
- Registry record last updated 2023-04-28; status last verified 2023-04.
- Results first posted 2023-04-28.
- 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 a completed Phase II, single-group study of an adenovirus/PSA vaccine in men with hormone-refractory prostate cancer. Recorded enrollment is 32. The intervention description specifies three subcutaneous injections of 0.16 ml, consisting of 0.125 ml vaccine and 0.035 ml Gelfoam per injection. Allocation is listed as NA and masking as none.
The primary outcome is the number of participants with stable, decreased, or increased PSA doubling times over 18 months; PSADT is described as calculated using the MSKCC online calculator. The primary outcome counts and secondary outcome results are not reported in the registry record. The record lists three outcome measures and zero analyses, without reporting the analysis plan, analysis populations, or missing-data methods.
Safety entries include 3 participants affected by serious adverse events, 18 affected by other adverse events, and 21 deaths; the registry also lists three serious-event terms at 3.1% each. These are descriptive entries and do not establish causality. The single-group design provides no concurrent randomized comparison.