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 Sipuleucel-T, CT-011, and Cyclophosphamide for Advanced Prostate Cancer (NCT01420965), a randomized phase 2 study. The primary outcome is Determine Feasibility of Provenge Plus Low-dose Cyclophosphamide as Well as the Immune Efficacy of Provenge Alone Versus Provenge Plus Low-dose Cyclophosphamide and Anti PD1 Monoclonal Antibodies (CT011) on the Change in Specific Immune Response..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01420965 |
| Phase | Phase 2 |
| Condition | Prostatic Neoplasms |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 7 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Augusta University |
| Results posted | Yes |
2. Clinical Question
Population
Men with advanced castrate-resistant prostate cancer. The eligibility summary specifies men at least 18 years of age with advanced prostate cancer. The registry records an enrollment of 7.
Intervention
The study evaluated sipuleucel-T alone and in combinations that included CT-011, an anti-PD-1 antibody, and low-dose cyclophosphamide. The registry describes three treatment arms: sipuleucel-T alone; sipuleucel-T with CT-011; and sipuleucel-T with cyclophosphamide and CT-011.
Comparator
The arm descriptions make sipuleucel-T alone the comparison for the combination regimens. The registry also describes the study as having two parts with different participants, but the allocation and comparison structure across those parts is not fully specified in the record.
Primary question
The primary objective was to assess feasibility and the change in a specific immune response with sipuleucel-T alone versus sipuleucel-T combined with low-dose cyclophosphamide and CT-011. The primary outcome timeframe is 2 years. The record states that the study was discontinued because of drug supply issues and that no analysis was performed or meaningful data derived.
This is therefore a question the trial set out to investigate, not a comparison with a reported estimate. The registry contains no primary endpoint result from which to judge the size, direction, or precision of an immune-response difference. It also does not give an operational definition of the immune response, the measurement procedure, or a result for feasibility. The study's secondary objective refers to progression-free survival and overall survival, but the record does not provide analyzed results for those outcomes.
3. Trial Design
The registry identifies this as a randomized, open-label, parallel Phase 2 study. It lists Augusta University as the sponsor, records a start date of 2012-09 and a primary completion date of 2016-12, and gives the study status as terminated. The registry reports enrollment of 7. It also says the study was discontinued because of drug supply issues, with no analysis performed or meaningful data derived for the primary objective.
The brief description separates the study into two parts with different participants. Arm descriptions identify three regimens: sipuleucel-T alone for 3 cycles; sipuleucel-T for 3 cycles with CT-011; and sipuleucel-T for 3 cycles with cyclophosphamide in the first cycle and CT-011. The listed cycle length is 14 days. For the combination arms, CT-011 is described as a 3mg/kg intravenous infusion delivered approximately 2 days after each sipuleucel-T infusion. The cyclophosphamide dose in the third arm is listed as 125 or 250mg/m2 in the first cycle.
The registry does not explain how participants were assigned to arms, whether allocation was balanced, or how the two parts relate to the three arm descriptions. It does not report an allocation sequence, concealment procedures, or a masking procedure beyond identifying the study as unmasked. Further details about planned recruitment, treatment adherence, or the conduct of follow-up are not reported in the registry record. These omissions matter because the registered design alone does not establish how closely the intended comparisons could be carried out before termination.
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 | Arm A | Arm B | Arm C |
|---|---|---|---|
| STARTED | 2 | 2 | 3 |
| COMPLETED | 1 | 1 | 3 |
| NOT COMPLETED | 1 | 1 | 0 |
Reasons for not completing this period:
| Reason | Arm A | Arm B | Arm C |
|---|---|---|---|
| Withdrawal by Subject | 1 | 0 | 0 |
| Adverse Event | 0 | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: Study discontinued due to drug supply issues; no analysis performed or meaningful data derived.
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 | Arm A | Arm B | Arm C | Total |
|---|---|---|---|---|---|
| Participants analysed | 2 | 2 | 3 | 7 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 1 | 1 | 3 | 5 |
| Age, Categorical: >=65 years | Participants | 1 | 1 | 0 | 2 |
| Sex: Female, Male: Female | Participants | 0 | 0 | 0 | 0 |
| Sex: Female, Male: Male | Participants | 2 | 2 | 3 | 7 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 | 0 | 0 | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 2 | 2 | 3 | 7 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 | 1 | 0 | 1 |
| Race (NIH/OMB): White | Participants | 1 | 1 | 3 | 5 |
| Race (NIH/OMB): More than one race | Participants | 1 | 0 | 0 | 1 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 | 0 |
| Region of Enrollment: United States | participants | 2 | 2 | 3 | 7 |
6. Primary Endpoint
The registry lists the primary outcome as Determine Feasibility of Provenge Plus Low-dose Cyclophosphamide as Well as the Immune Efficacy of Provenge Alone Versus Provenge Plus Low-dose Cyclophosphamide and Anti PD1 Monoclonal Antibodies (CT011) on the Change in Specific Immune Response., measured over 2 years.
| 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 objective combines a feasibility question with an immune-response question. The stated immune objective is to assess the change in a specific immune response with sipuleucel-T alone compared with sipuleucel-T plus low-dose cyclophosphamide and CT-011. The registry lists a timeframe of 2 years. It does not identify the immune measure, assay, collection schedule, definition of change, or threshold that would count as a meaningful response. Feasibility is named in the objective, but its criteria are not described.
As general statistical context, an immune-response endpoint can be used to assess a biological effect of a treatment regimen. Such an endpoint is not interchangeable with a clinical outcome: the meaning of a measured immune change depends on what was measured and how the measure relates to outcomes of interest. A clear endpoint definition also supports reproducible measurement and makes it possible to interpret the size and uncertainty of a comparison.
Here, there is no reported primary endpoint estimate because the registry says no analysis was performed and no meaningful data were derived. Consequently, the record does not show whether an immune response changed, whether the regimens differed, or how precisely any difference could have been estimated. The secondary objective mentions progression-free survival and overall survival, but no corresponding analyzed results are reported in this record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive point is that the registry reports a study objective and treatment groups, but no primary outcome analysis. It explicitly attributes discontinuation to drug supply issues and says that no analysis was performed or meaningful data derived. There is therefore no posted estimate of change in specific immune response to interpret. The record supplies no effect estimate, confidence interval, hypothesis-test result, or analysis population for that endpoint.
This is not evidence that the treatments had equal effects, nor is it evidence that one regimen was better or worse. An absent result cannot distinguish a small effect from a large effect, and it cannot establish that the regimens were equivalent. The study's termination and lack of analysis mean that the intended comparison remains unanswered by the posted primary results. The randomized designation describes the planned or registered design; it does not itself supply evidence about the outcome.
The record's secondary objective refers to possible changes in progression-free survival and overall survival. Those are stated objectives, not results. The registry record does not report analyzed estimates for either outcome. No conclusion about survival or disease progression can be drawn from an objective alone.
The enrollment entry is 7, but this does not substitute for an analysis. The adverse-event information is a separate descriptive component: it lists serious events and other events by arm, with small at-risk counts. Those counts describe what the registry reports for safety; they do not recover the missing immune endpoint or provide an estimate of comparative efficacy. The record does not specify the follow-up completeness or the observation period underlying those event figures.
As general statistical context, estimates from a trial are most informative when accompanied by uncertainty measures and a clear account of the data included. A confidence interval, when available, communicates a range of values compatible with the data and the model; it does not make an unperformed analysis possible. In this record there is no primary estimate or interval, so precision cannot be assessed. The appropriate reading is limited: the trial was registered as a randomized parallel study, was terminated because of drug supply issues, and yielded no reported primary analysis or meaningful primary outcome data.
9. Statistical Methods Explained
The registry describes a randomized, parallel Phase 2 study and identifies no masking. These design labels describe different aspects of a trial. Randomization is a method intended to allocate participants by chance, which can reduce systematic differences between treatment groups at the point of assignment. A parallel design means that treatment groups are compared as separate groups rather than participants crossing through each regimen. Open-label means that masking was not used as recorded. These features describe the registered design; they do not establish that a complete comparative analysis was ultimately possible.
What does randomization contribute?
As general statistical context, random allocation can support a fair comparison because, on average, it helps distribute participant characteristics across treatment groups without relying on investigator choice. Its value depends on the allocation process being implemented and on the subsequent analysis respecting the comparison. The registry does not report the sequence-generation method, allocation concealment, or the allocation ratio. With enrollment recorded as 7 and no primary analysis, the record cannot demonstrate how well groups were balanced or quantify a treatment contrast.
What would an effect estimate and confidence interval tell a reader?
As general context, an effect estimate describes the observed contrast for a specified outcome and comparison. A confidence interval expresses uncertainty around that estimate under the statistical method used. A narrow interval generally indicates greater precision than a wide interval, while the interval's location helps convey which effect values are compatible with the data. Neither an estimate nor an interval is reported for the primary immune-response objective in this record. Since no primary analysis was performed, there is no result from which to evaluate magnitude, direction, or precision.
Why does the endpoint definition matter?
As general context, the statistical analysis depends on an endpoint that specifies what is measured, when it is measured, and how the response is summarized. A change outcome also needs a clearly defined reference measurement and follow-up measurement. Without these details, a reader cannot determine what a reported change would represent or whether different participants' measurements could be compared consistently. The registry names a specific immune response and a 2 years timeframe, but the immune marker, measurement procedure, timing details, and change definition are not reported in the registry record.
What can be learned from the analysis fields?
The registry reports no primary analysis and no meaningful data derived. It lists no analyses in the record. Therefore, there is no sponsor analysis to compare with a recalculation from posted summary statistics, and no recalculated effect should be inferred. Statistical methods such as adjustment for baseline characteristics, repeated-measures modeling, or time-to-event analysis cannot be attributed to the study unless reported. The analysis plan and any model specifications are not reported in the registry record.
As general context, a statistical model is chosen to match the outcome and design. A continuous immune measure might be summarized or modeled differently from a binary response, while a time-to-event outcome requires methods that account for follow-up time and censoring. The registry does not state the scale or structure of the primary immune endpoint, so no particular model can be identified. It also does not report how data from the two study parts were intended to be combined or compared.
How should planning illustrations be interpreted?
As general context, a sample-size calculation is a planning exercise, not an observed result. The registry's stated planning assumptions describe two-sided significance level 0.05, equal allocation between two arms, and a normal approximation, with the target effect described as a fraction of the observed effect. For time-to-event calculations, the stated convention is to give total events; other calculations are described as participants per arm. These assumptions do not show that the trial achieved a particular power or that any treatment effect was observed. No primary effect estimate is reported in the registry record, so a planning illustration cannot supply the missing trial result.
Power is a design property under specified assumptions about an effect, variability, and analysis. It is not an observed probability that a finding is true, and a small or terminated study cannot be interpreted through a retrospective observed-power claim. In this case, no analyzed primary effect is available to anchor such an interpretation. The registry does not report a sample-size justification, target enrollment rationale, or interim-analysis plan.
Finally, the safety counts are descriptive, not substitutes for the primary statistical analysis. A count of events in an arm does not by itself identify a causal effect, especially when the groups are small and follow-up details are not reported. The registry does not provide a comparative safety model, uncertainty estimates, or a detailed analysis plan for adverse events. The record supports description of the entries, but not stronger inferential claims.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one primary objective and a secondary objective that refers to progression-free survival and overall survival. It does not report a statistical plan for controlling multiplicity across outcomes, treatment comparisons, immune measures, or time points. The primary description itself combines feasibility and immune efficacy, but the record does not define separate tests or a hierarchy for those aims. It is therefore not possible to determine whether any planned inference was intended to account for multiple comparisons.
As general statistical context, testing several outcomes or comparisons can increase the chance of observing an apparently notable result by chance if multiplicity is not addressed. A prespecified hierarchy or adjustment can clarify how results should be interpreted. No such procedure is reported in the registry record, and no primary analysis was performed, so there is no set of inferential results to assess for multiplicity.
The registry states that no analysis was performed or meaningful data derived for the primary outcome. It does not report participant-level missingness, reasons for missing measurements beyond the study's discontinuation due to drug supply issues, follow-up completeness, or methods for handling missing values. It also does not define an analysis population, such as all randomized participants or participants with evaluable endpoint data. Consequently, the available record cannot show who contributed to a primary outcome analysis or how incomplete observations might have affected an estimate.
As general context, missing-data methods rely on assumptions about why measurements are absent. Those assumptions should be stated because different approaches can produce different interpretations. No imputation, sensitivity analysis, or missing-data assumption is reported. The record's termination statement explains the stated reason for discontinuation, but it does not detail the extent or pattern of missing endpoint data.
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 |
|---|---|---|---|
| Arm A | 0 | 2 | 0.0% |
| Arm B | 1 | 2 | 50.0% |
| Arm C | 0 | 3 | 0.0% |
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 |
|---|---|
| Arm A | 0 of 2 |
| Arm B | 0 of 2 |
| Arm C | 0 of 3 |
Most frequent serious adverse event terms
| Event term | Organ system | Arm A | Arm B | Arm C |
|---|---|---|---|---|
| Negative infusion reaction | Immune system disorders | 0 of 2 | 1 of 2 | 0 of 3 |
Serious events with the highest arm-level rate: negative infusion reaction (50.0%).
The safety entries are reported by arm. For serious adverse events, the registry lists 0 affected among 2 at risk in Arm A, 1 affected among 2 at risk in Arm B, and 0 affected among 3 at risk in Arm C. For other adverse events, it lists 0 affected in each arm, with at-risk counts of 2, 2, and 3 respectively. The top serious term is listed as Negative infusion reaction, 50.0%.
These are descriptive registry entries, not a complete comparative safety analysis. The record does not explain the denominator or calculation underlying the 50.0% term listing, so that percentage should not be treated as an arm-specific risk or connected to a particular event count without further documentation. Death counts are not reported in the record. Follow-up duration, event ascertainment procedures, severity grading details, and statistical comparisons are also not reported in the registry record.
As general statistical context, event counts are easier to interpret when their definitions, observation periods, and denominators are clear. Small group counts can be especially sensitive to each recorded event, and descriptive differences alone do not establish that a treatment caused an event. The posted safety figures should therefore be read narrowly as the registry's reported counts and term listing, not as evidence of a causal safety difference between regimens.
12. What the Result Does, and Does Not, Mean
The result that can be stated is a result about study conduct and reporting: the registry says the study was discontinued because of drug supply issues and that no analysis was performed or meaningful data derived for the primary objective. The primary question concerned feasibility and change in a specific immune response. No result answers that question in the registry record.
This does not mean that the treatment regimens had no effect, that they were equivalent, or that an effect was present. It also does not establish that the study's objective was achieved or not achieved. Without an analyzed endpoint, there is no estimate of effect size and no uncertainty interval with which to assess precision. The registry's randomized label and arm descriptions cannot replace outcome data.
The survival outcomes in the secondary objective are also not results. The record mentions progression-free survival and overall survival as objectives but provides no analyzed findings for them. The adverse-event entries offer limited descriptive information, but they do not address the primary immune endpoint and do not support a comparative efficacy conclusion.
As general statistical context, a trial can be informative through a completed analysis, but incomplete or unreported outcome data limit what readers can learn about the treatment contrast. In this case, the record documents the intended study question and some design and safety information, while leaving the primary outcome unanswered. Any further conclusion about benefit, lack of benefit, or comparative clinical effect would go beyond what is reported.
13. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the distinction between a registered question and an analyzed result. The record identifies a randomized comparison involving sipuleucel-T alone and combination regimens, but it also explicitly says that no primary analysis was performed and no meaningful data were derived. The design can describe what investigators intended to compare; it cannot establish what the comparison would have shown.
The record also shows why endpoint definition and analysis planning are important. The primary objective refers to a change in specific immune response, but does not identify the measure, measurement schedule, or operational definition of change. Without those details and a completed analysis, readers cannot assess the estimand, interpret the scale, or evaluate precision. The secondary survival objective likewise has no reported analyzed outcomes.
As general statistical context, clear reporting of outcome definitions, analysis populations, missing data, and uncertainty helps readers distinguish an inconclusive estimate from an absent estimate. Those are not the same situation. An inconclusive estimate still describes observed data and their uncertainty; an unperformed analysis supplies no such estimate. The registry's explanation for termination is important context, but it does not resolve the unanswered treatment questions.
The record therefore contributes information about the planned design, termination, and limited safety entries, while demonstrating that registration and randomization alone do not guarantee interpretable efficacy evidence. This distinction is useful when reading any trial record: statistical conclusions must be tied to results that were actually analyzed and reported.
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 is explicit: the registry states that the study was discontinued because of drug supply issues and that no analysis was performed or meaningful data derived for the primary endpoint. As a result, no primary effect estimate or measure of precision is available. The record cannot support a conclusion about immune response or feasibility.
Other limitations arise from incomplete methodological detail. Although the study is identified as randomized, parallel, and unmasked, the allocation procedure and ratio are not reported in the registry record. The relationship between the two study parts and the three described arms is not fully explained. The registry does not report a detailed statistical analysis plan, sample-size justification, interim-analysis plan, or analysis population.
The primary outcome is described as a change in specific immune response, but the immune measure, assay, assessment schedule, and definition of change are not given. Feasibility criteria are also absent. The secondary objective mentions progression-free survival and overall survival, but analyzed results and relevant operational details are not reported in the registry record.
The safety entries have limited context. The record does not explain the denominator for the listed 50.0% serious-event term, and death counts are not reported. Details about event definitions, follow-up, and missing observations are not given. These limitations mean that the safety figures should remain descriptive and that neither safety nor efficacy comparisons can be reconstructed from the registry entries alone.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Sipuleucel-T, CT-011, and Cyclophosphamide for Advanced Prostate Cancer — NCT01420965.
- Registry record last updated 2019-07-10; status last verified 2019-06.
- Results first posted 2019-07-10.
- 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 NCT01420965 as a randomized, unmasked, parallel Phase 2 study sponsored by Augusta University. It evaluated sipuleucel-T alone and regimens combining sipuleucel-T with CT-011, with cyclophosphamide included in one described arm. The population was men with advanced castrate-resistant prostate cancer, and the record lists enrollment of 7.
The primary objective concerned feasibility and change in a specific immune response, with a timeframe of 2 years. The study status is terminated; the record attributes discontinuation to drug supply issues and states that no analysis was performed or meaningful data derived. The registry does not report a primary endpoint result or analyzed survival results. It lists serious and other adverse-event counts by arm, but their limited context does not support broader comparative conclusions.