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 Androgen Deprivation Therapy and Vorinostat Followed by Radical Prostatectomy in Treating Patients With Localized Prostate Cancer (NCT00589472), a na phase 2 study. The primary outcome is Pathologic Complete Response at the Time of Surgery.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00589472 |
| Phase | Phase 2 |
| Condition | Prostate Adenocarcinoma, Stage I Prostate Cancer, Stage IIA Prostate Cancer |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 19 |
| Arms in the primary outcome | n/a |
| Lead sponsor | National Cancer Institute (NCI) |
| Results posted | Yes |
2. Clinical Question
Population
The trial enrolled patients with prostate cancer that had not spread to other parts of the body. The listed conditions include prostate adenocarcinoma and Stage I, Stage IIA, Stage IIB, and Stage III prostate cancer. Enrollment was 19 participants. The registry describes the study as phase II and gives the primary endpoint timeframe as 12 weeks.
Intervention
The intervention combined androgen-deprivation therapy with vorinostat before radical prostatectomy. The registry describes bicalutamide by mouth once daily for 1 month, with leuprolide acetate by injection or goserelin acetate by injection once a month until surgery. Vorinostat was taken by mouth once daily, starting on the first day of androgen-depletion therapy and continuing for up to 8 weeks or until surgery.
Comparator
This was a single-group study with no randomized control group. The registry lists allocation as not applicable and masking as none. As a result, the study does not provide a concurrent group receiving a different treatment against which to compare the preoperative regimen.
Primary question
The primary question was whether pathological complete response was observed at surgery after the preoperative regimen. The registry defines this as no evidence of disease in the prostate in the posttherapy pathology specimen. The observed number of participants with this outcome is not reported in the registry record, so the primary clinical result cannot be described from the posted information.
3. Trial Design
This was a phase II, single-group trial sponsored by the National Cancer Institute (NCI). The registry lists 19 participants as enrolled. The study began in 2007-11, had a primary completion date of 2010-06, and is marked completed. Its title identifies androgen-deprivation therapy and vorinostat followed by radical prostatectomy as the treatment sequence for localized prostate cancer.
The treatment arm description specifies bicalutamide by mouth once daily for 1 month, together with either leuprolide acetate by injection or goserelin acetate by injection once a month until surgery. Vorinostat by mouth once daily was to begin on the first day of androgen-depletion therapy and continue for up to 8 weeks or until the day of surgery. Radical prostatectomy followed the preoperative drug treatment. The arm description is truncated after its reference to what happens next, so no additional treatment details can be established from that text.
There was no random allocation and no masking. Because the design has a single treatment group, observed outcomes can describe what happened among enrolled participants, but the design does not provide a direct concurrent estimate of what would have happened under another treatment. The registry does not report a control group or a planned between-group comparison.
The primary endpoint was pathological complete response at the time of surgery, with a stated timeframe of 12 weeks. The registry also lists secondary outcomes including Gleason score and levels of DHEA, DHEA-S, DHT, PSA, and testosterone in blood from radical prostatectomy specimens. It lists 17 outcome measures overall, but observed outcome values and analysis results are not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Treatment (Antihormone Therapy and Enzyme Inhibitor Therapy) |
|---|---|
| STARTED | 19 |
| COMPLETED | 18 |
| NOT COMPLETED | 1 |
Reasons for not completing this period:
| Reason | Treatment (Antihormone Therapy and Enzyme Inhibitor Therapy) |
|---|---|
| Adverse Event | 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 | Treatment (Antihormone Therapy and Enzyme Inhibitor Therapy) |
|---|---|---|
| Participants analysed | 19 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 14 |
| Age, Categorical: >=65 years | Participants | 5 |
| Sex: Female, Male: Female | Participants | 0 |
| Sex: Female, Male: Male | Participants | 19 |
6. Primary Endpoint
The registry lists the primary outcome as Pathologic Complete Response at the Time of Surgery, measured over At 12 weeks.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
Pathological complete response at the time of surgery was the primary endpoint. The registry defines a response as no evidence of disease in the prostate, meaning that the posttherapy pathology specimen has no tumor. This is a binary participant-level outcome: each participant is assessed as having or not having the specified response. The stated assessment timeframe is 12 weeks.
Pathology after surgery provides a direct assessment of the removed prostate specimen. In general, this kind of endpoint is used to describe whether tumor is detectable in the surgical tissue after preoperative treatment. It is distinct from measurements of hormone levels, PSA, or Gleason score, which the registry lists as secondary outcomes. Those measures address different features and are not substitutes for the primary endpoint as defined in the record.
The registry describes a planned analysis of response probabilities, but it does not report the observed response count or proportion. Therefore, the posted information does not establish how many participants met the pathological complete-response definition. Nor does it allow a confidence interval or a statistical comparison for the observed response to be stated. The endpoint definition and its planned role are recorded, while the result needed to assess the endpoint is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The record describes the study design and the intended primary endpoint, but it does not post the observed pathological complete-response result. In particular, it does not state the number of participants with no evidence of disease in the prostate specimen, the number assessed for this outcome, or an estimated response proportion. Without those data, the primary outcome cannot be quantified or interpreted as an observed study finding.
Enrollment was 19 participants, while the endpoint description says that a maximum of 38 participants were planned. These are different pieces of information: the first is the registry’s enrollment figure, and the second is the planned maximum in the described design. The record does not explain why enrollment was below that planned maximum. It also does not give the number who underwent surgery or the number whose pathology specimens were available for the primary endpoint. The enrolled count therefore should not be treated as the denominator for an observed response rate.
The planned Simon 2-stage optimal design was described as distinguishing response probabilities of 0.05 and 0.20, with Type I error 10% and power 90%. The registry says the trial was to stop if zero or one response was observed. These are design features, not the observed result. They do not show that the planned stopping rule was triggered, that a response occurred, or that the planned operating characteristics were achieved in practice. The record does not report the stage-specific enrollment or response counts needed to assess implementation.
Because this is a single-group study, any reported response proportion would describe outcomes in the treated group rather than estimate a treatment effect against a concurrent control group. General statistical interpretation of a single proportion depends on both its numerator and denominator, and uncertainty is important when the number of observations is limited. Neither an observed proportion nor its uncertainty is posted for the primary endpoint.
The safety information lists 2 participants with serious adverse events and 17 with other adverse events, among 19 at risk in each category. Those figures describe the registry’s adverse-event entries; they do not fill the gap in the primary efficacy outcome. The registry also lists thrombosis and hypertension among the top serious terms, each at 5.3%. The posted information does not permit a causal comparison of safety with another regimen or population.
Overall, the record supports a description of the intended treatment sequence, study structure, endpoint definition, planned response design, and listed safety counts. It does not provide the observed primary endpoint result or enough information to assess a treatment effect. That distinction between a planned statistical design and an available study result is central to interpreting this trial.
9. Statistical Methods Explained
What does a single-group design estimate?
A single-group study observes outcomes among participants receiving the study regimen. In general, an estimated response proportion describes the frequency of the defined outcome in that group. It does not, by itself, separate the effect of treatment from other explanations, such as the natural course of disease, participant selection, or differences in follow-up. A concurrent comparison group can address some of these questions, but this trial is listed as single group, with allocation not applicable and no masking.
For this trial, the primary endpoint is a binary outcome: pathological complete response is defined as absence of tumor in the posttherapy prostate pathology specimen. To estimate a response proportion, the analysis needs the number meeting that definition and the number assessed. The registry does not report those counts. A response estimate, confidence interval, or test result therefore cannot be reconstructed from the posted record.
What does the planned Simon design mean?
The registry describes a Simon 2-stage optimal design for the pathological complete-response endpoint. In general, a two-stage design evaluates accumulating outcome information at an interim stage and can stop early under a prespecified rule. This structure can limit continued enrollment when early outcomes meet a stopping criterion. The record says that the trial was to stop if zero or one response was observed. It does not report stage-specific enrollment or response counts, so it is not possible to determine whether this rule was applied or whether it led to stopping.
The design was stated to distinguish response probabilities of 0.05 and 0.20, with Type I error 10% and power 90%. In general, the Type I error is the planned probability of rejecting a reference condition when that condition is true, under the design assumptions. Power is the planned probability of detecting the specified alternative under the assumptions and analysis plan. These are prospective design properties, not measures of what the study actually observed. The registry also describes a one-sided 0.10 size test and says the design had power 0.90 for a population response proportion to 0.20. No observed test statistic or p-value is reported.
The registry states a maximum planned accrual of 38 participants. Enrollment is listed as 19. The record does not explain the difference, and it does not report whether recruitment ended early, whether eligibility or follow-up affected enrollment, or whether the stopping rule determined the final sample. Those possibilities cannot be inferred from the enrollment and design statements alone.
How should uncertainty be understood?
In general, a confidence interval describes a range of values compatible with the observed data under a specified method. For a binary endpoint, its precision depends on the event count and the number assessed. A small dataset can yield substantial uncertainty, but the amount cannot be quantified without the actual outcome count and denominator. No interval for the primary response is reported in the registry record.
There is no sponsor-reported primary endpoint analysis in the posted record. As a result, there is no sponsor estimate to compare with a recalculated estimate, and no recalculation can be made from summary statistics. The planned design values should not be mistaken for an observed effect, and power is not an observed property of the completed participant group.
What do the secondary outcomes add?
The registry lists Gleason score and measurements of DHEA, DHEA-S, DHT, PSA, and testosterone in blood from radical prostatectomy specimens among the secondary outcomes. These are distinct outcome domains. In general, reporting several endpoints raises questions about how outcomes were selected, how analyses were specified, and whether any adjustment was made for multiple testing. The registry record does not report analysis results for these outcomes or a multiplicity procedure. Their listing alone does not establish what was measured successfully or what findings were obtained.
The registry notes that pT2 indicates cancer confined to the prostate and pT3 indicates extraprostatic extension. Those definitions clarify pathology terminology, but the posted information does not give participant counts by pathological stage. The definitions should therefore not be read as evidence about the distribution of participants or the treatment response.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 17 outcome measures, including the primary pathological complete-response endpoint and secondary measures such as Gleason score and hormone and PSA levels. It lists zero analyses. The record does not report which outcomes were analyzed, how each outcome was handled, or whether results were withheld, unavailable, or not entered. The mere presence of an outcome in the registry does not establish that it was measured or analyzed.
Multiplicity concerns arise in general when several outcomes or statistical tests are considered. Repeated testing can increase the chance of at least one apparently notable finding, depending on the tests and analysis strategy. The registry record does not report a multiplicity adjustment, a hierarchy for secondary outcomes, or a plan for interpreting multiple tests. It is therefore not possible to determine how the set of listed outcomes was handled statistically.
Missing-data methods are not reported in the registry record. The record does not state how participants without a surgery specimen, participants with incomplete measurements, or other unavailable observations were treated in the analysis. It also does not report the number assessed for each endpoint or reasons for missing outcome data. Consequently, the enrolled count of 19 cannot be assumed to be the analysis denominator for every outcome.
Analysis populations are not reported in the registry record. No population definition is given for the primary analysis, such as which enrolled participants would be included or how protocol deviations would be treated. With no posted analyses or participant flow information, the handling of exclusions and incomplete follow-up cannot be assessed.
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 |
|---|---|---|---|
| Treatment (Antihormone Therapy and Enzyme Inhibitor Therapy) | 2 | 19 | 10.5% |
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 |
|---|---|
| Treatment (Antihormone Therapy and Enzyme Inhibitor Therapy) | 17 of 19 |
Most frequent serious adverse event terms
| Event term | Organ system | Treatment (Antihormone Therapy and Enzyme Inhibitor Therapy) |
|---|---|---|
| Thrombosis | Cardiac disorders | 1 of 19 |
| Hypertension | Vascular disorders | 1 of 19 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Treatment (Antihormone Therapy and Enzyme Inhibitor Therapy) |
|---|---|---|
| Anemia | Blood and lymphatic system disorders | 11 of 19 |
| Hyperglycemia | Metabolism and nutrition disorders | 11 of 19 |
| Hypocalcemia | Metabolism and nutrition disorders | 8 of 19 |
| Lymphocyte count decreased | Investigations | 4 of 19 |
| Creatinine increased | Investigations | 2 of 19 |
| Hypertension | Vascular disorders | 2 of 19 |
| INR increased | Investigations | 2 of 19 |
| Activated partial thromboplastin time prolonged | Investigations | 1 of 19 |
| Blood bilirubin increased | Investigations | 1 of 19 |
| Cardiac disorders-Other, specify | Cardiac disorders | 1 of 19 |
Serious events with the highest arm-level rate: thrombosis (5.3%), hypertension (5.3%).
The registry lists 19 participants at risk for serious adverse events and 2 participants affected in that category. It also lists 19 at risk for other adverse events and 17 affected. These are participant counts, not a comparison between treatment groups, because the trial had a single group. The categories should be read as separate registry entries; the record does not explain whether participants with serious events are also included in the other-event count.
Thrombosis and hypertension are listed among the top serious adverse-event terms, each at 5.3%. The record does not provide event-level details, timing, severity grades, attribution to study treatment, or a denominator specific to those terms. It also does not report a comparator group or a safety analysis adjusted for exposure duration. The listed percentages therefore should be read as registry-reported figures, not as comparative risks or evidence about causation.
In general, adverse-event counts describe events recorded under the study’s reporting definitions. Interpretation depends on how events were collected, classified, and attributed. Those methods are not reported in the registry record. The safety entries do not provide a basis for medical advice or for comparing this regimen with another treatment.
12. What the Result Does, and Does Not, Mean
The trial addresses a defined preoperative treatment strategy: androgen-deprivation therapy with vorinostat before radical prostatectomy for localized prostate cancer. Its primary endpoint was also clearly specified as pathological complete response in the surgical prostate specimen. These features make the research question and planned outcome identifiable in the registry.
However, the posted record does not report the observed primary endpoint result. Without the response count and number assessed, it is not possible to describe the frequency of pathological complete response in this study, quantify its precision, or determine whether the observed data were consistent with the planned response probabilities. The Simon design’s target probabilities and operating characteristics are planning statements, not evidence of an observed response.
Even if a response estimate were available, a single-group phase II design would describe outcomes among participants treated in the study and would not provide a randomized comparison. Such a design cannot, by itself, establish what outcomes would have occurred under another treatment. The registry provides no concurrent comparator and no masking.
The listed adverse-event counts provide some safety information, but the record does not give detailed event definitions, attribution, or comparative data. These entries should not be extended into a conclusion about relative safety. The secondary outcome list also does not indicate results: actual values for Gleason score, DHEA, DHEA-S, DHT, PSA, and testosterone are not reported in the registry record.
Thus, the registry documents a planned clinical question, treatment sequence, endpoint definition, statistical design, enrollment, and selected adverse-event counts. It does not document the primary outcome result or analyses needed to evaluate the planned endpoint. The absence of a posted result is not evidence that no response occurred, and it is not evidence that the regimen did or did not alter outcomes. It means that the relevant observed result cannot be determined from this record.
13. Why This Trial Matters Statistically
This trial is statistically notable for the way its registry links a binary pathological endpoint to a prospective two-stage design. The endpoint definition is concrete: no tumor in the posttherapy prostate specimen at surgery. The design description also identifies response probabilities it was intended to distinguish, an error rate, power, a maximum planned accrual, and an early stopping rule. Together, these details show how an outcome definition and a decision framework can be specified before results are available.
At the same time, the record illustrates why planned statistical properties must be separated from observed findings. The planned power of 90% does not reveal how many responses occurred, and the planned stopping criterion does not establish whether the study stopped at an interim stage. Enrollment was 19, while the stated maximum was 38; the record does not explain the difference. Without stage-specific outcome counts, the design’s operation cannot be evaluated.
The single-group structure is another important statistical feature. It allows the study to describe outcomes in the treated participants, but it does not supply a direct control-group contrast. This limitation matters when interpreting any outcome as an effect attributable to treatment. Here, the absence of a posted primary result adds a separate limitation: even a descriptive response estimate is unavailable.
The registry also lists multiple secondary outcomes but no analyses. This emphasizes that outcome registration and outcome reporting are not the same. A list can clarify what investigators intended to assess, while still leaving questions about actual measurement, analysis, missing data, and multiplicity unanswered. The study is therefore useful as an example of the distinction between a prespecified statistical plan and a complete, interpretable results record.
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 trial-specific limitation is that the registry does not report the observed primary endpoint result. It provides no response count, analysis denominator, estimate, confidence interval, or test result for pathological complete response. The study’s planned response probabilities and design characteristics cannot replace those observed data.
The single-group design has no concurrent control group, and the registry lists no random allocation or masking. Accordingly, the record does not support a randomized treatment comparison. Enrollment is listed as 19, while the described design planned a maximum of 38; the reason for the difference is not reported in the registry record. Participant flow, completion of surgery, and endpoint availability are also not described.
The arm description is incomplete in the registry text, ending after a truncated statement about what participants did after receiving the preoperative treatment. The record does not report adherence, treatment discontinuations, surgery timing for individual participants, or deviations from the regimen. These details could affect interpretation of both efficacy and safety, but cannot be inferred.
Although 17 outcome measures are listed, the registry gives no analysis results and lists zero analyses. It does not report missing-data methods, analysis populations, multiplicity handling, or detailed definitions for the secondary measurements. For adverse events, participant counts and selected serious-event terms are listed, but event attribution and fuller collection methods are not reported in the registry record. These gaps limit interpretation of the posted safety information as well as the planned clinical outcomes.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Androgen Deprivation Therapy and Vorinostat Followed by Radical Prostatectomy in Treating Patients With Localized Prostate Cancer — NCT00589472.
- Registry record last updated 2017-10-06; status last verified 2017-09.
- Results first posted 2017-10-06.
- 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 record describes a completed phase II, single-group study sponsored by the National Cancer Institute (NCI), with 19 participants enrolled. The study evaluated androgen-deprivation therapy and vorinostat before radical prostatectomy for localized prostate cancer. Its primary endpoint was pathological complete response at surgery, defined as no evidence of disease in the prostate specimen, with a stated timeframe of 12 weeks.
The record describes a Simon 2-stage optimal design, including response probabilities of 0.05 and 0.20, Type I error 10%, power 90%, a maximum planned accrual of 38, and a stopping rule if zero or one response was observed. The observed primary endpoint result and analysis are not reported in the registry record. Safety entries list 2 participants with serious adverse events and 17 with other adverse events, among 19 at risk in each category; thrombosis and hypertension are each listed at 5.3% among the top serious terms.