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 (PGA) for Platinum-resistant/Refractory, Paclitaxel-Pretreated Recurrent Ovarian and Peritoneal Carcinoma (NCT01936974), a randomized phase 2 study. The primary outcome is Progression-free Survival.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01936974 |
| Phase | Phase 2 |
| Condition | Ovarian Carcinoma, Fallopian Tube Carcinoma, Peritoneal Carcinoma |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 7 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Western Regional Medical Center |
| Results posted | Yes |
2. Clinical Question
Population
People with recurrent ovarian or peritoneal carcinoma described as platinum-resistant or refractory and paclitaxel-pretreated were the intended population. The listed conditions also include fallopian tube carcinoma. The registry record does not give further eligibility criteria or describe the enrolled participants’ characteristics.
Intervention
One regimen combined platinum, gemcitabine and bevacizumab. Carboplatin was specified as the platinum drug, with cisplatin or oxaliplatin described as alternatives in cases of allergy. Gemcitabine and bevacizumab were also part of this regimen.
Comparator
The comparison regimen consisted of gemcitabine and bevacizumab, without a platinum drug listed. The record describes gemcitabine on days 1 and 8 and bevacizumab on day 1 for this arm. Doses and treatment duration are not reported in the registry record.
Primary question
The study aimed to evaluate progression-free survival between the regimens at the stated one-year timeframe. Because the record says the data were not collected and results could not be retained, it does not provide an observed comparison of progression-free survival.
In statistical terms, the planned question was comparative: whether progression-free survival differed between the assigned regimen groups in the target clinical population. Random allocation is recorded, but the registry record does not describe the allocation procedure, concealment, or how the single masking was implemented. It also does not report a treatment-effect estimate, uncertainty interval, or test result. The intended question is therefore distinguishable from what can be concluded from the posted results: the record documents a comparison that was planned, not an analyzable result establishing the direction or size of any difference.
3. Trial Design
The registry describes NCT01936974 as a phase 2, randomized, single-masked, parallel trial. The study compared a regimen of platinum, gemcitabine and bevacizumab with a regimen of gemcitabine and bevacizumab. The recorded enrollment is 7. The listed conditions are ovarian carcinoma, fallopian tube carcinoma and peritoneal carcinoma; the title and summary focus on recurrent platinum-resistant or refractory ovarian and peritoneal carcinoma in people pretreated with paclitaxel.
The platinum-containing arm specifies carboplatin on day 1, with cisplatin as an alternative for a patient allergic to carboplatin and oxaliplatin as an alternative if the patient is allergic to both carboplatin and cisplatin. Gemcitabine and bevacizumab are also listed on day 1 for this arm. The comparison arm specifies gemcitabine on days 1 and 8 and bevacizumab on day 1. The registry record does not give doses, cycle length, treatment duration, or details of how the alternative platinum choices were assigned.
The recorded start was 2013-09 and the primary completion was 2015-08. The study status is TERMINATED. The primary outcome is progression-free survival at One Year. Its description says the aim was to evaluate progression-free survival between the regimens. However, the outcome population text states that data were not collected because the study was terminated after the principal investigator was no longer employed at CTCA and did not have rights to the trial information; it also states that results could not be retained after much effort. The registry lists one outcome measure and no analyses. Thus, the design can be described, but the comparative outcome cannot be reconstructed from 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 | Platinum, Gemcitabine and Bevacizumab | Gemcitabine and Bevacizumab |
|---|---|---|
| STARTED | 2 | 5 |
| COMPLETED | 0 | 0 |
| NOT COMPLETED | 2 | 5 |
Reasons for not completing this period:
| Reason | Platinum, Gemcitabine and Bevacizumab | Gemcitabine and Bevacizumab |
|---|---|---|
| Physician Decision | 2 | 5 |
Analysis population for the primary outcome, as defined in the registry: Data not collected. The study has been terminated due to the PI no longer being employed at CTCA and not having rights to the trial information.After much effort, results were not able to be retained.
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: Baseline data were not collected. No data was collected for this study.
| Characteristic | Unit | Platinum, Gemcitabine and Bevacizumab | Gemcitabine and Bevacizumab | Total |
|---|---|---|---|---|
| Participants analysed | 0 | 0 | 0 | |
| Age, Categorical: <=18 years | — | — | — | |
| Age, Categorical: Between 18 and 65 years | — | — | — | |
| Age, Categorical: >=65 years | — | — | — | |
| Sex: Female, Male: Female | — | — | — | |
| Sex: Female, Male: Male | — | — | — | |
| Region of Enrollment: United States | participants | — | — | — |
6. Primary Endpoint
The registry lists the primary outcome as Progression-free Survival, measured over One Year.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
Progression-free survival is a time-to-event outcome. In general, it describes the time from a defined starting point until disease progression or death, according to the trial’s endpoint rules. Such outcomes are often used in oncology trials because they capture how long participants remain alive without a recorded progression event. The exact event definition and rules applied in this trial are not reported in the registry record, so the general description should not be taken as confirmation of the study’s specific measurement procedure.
The stated timeframe is One Year, and the primary outcome description says progression-free survival was to be evaluated between the two regimens. The record does not state the time origin, how progression was assessed, the assessment schedule, how deaths were handled, or how follow-up ended for participants without a recorded event. It also does not provide an outcome value, a survival curve, a hazard ratio, or another comparative estimate. Most importantly, the outcome population text says data were not collected and results could not be retained. The intended endpoint is identifiable, but its observed value and precision are not available in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive point is that the registry documents a randomized comparison but does not report the primary outcome data. The study’s stated aim was to compare progression-free survival for a platinum-containing regimen with progression-free survival for gemcitabine and bevacizumab. The record identifies One Year as the outcome timeframe, but it does not provide the event data or any treatment-effect estimate. Consequently, it is not possible to tell from the posted results whether progression-free survival differed between the groups, or to assess the size or precision of a possible difference.
The registry records enrollment of 7, but enrollment alone does not indicate how many participants contributed evaluable follow-up or outcome information. Group-specific enrollment and analysis counts are not reported in the registry record. The stated reason for the absence of the primary data is that the study was terminated after the principal investigator was no longer employed at CTCA and did not have rights to the trial information, and that results could not be retained. This is a limitation on what can be interpreted, not evidence about the outcome itself.
The adverse-event entries also require caution. The record displays zero for the listed serious and other event counts and for deaths in both groups. These entries do not establish that no events occurred: the primary outcome text explicitly says data were not collected, and the record does not clarify whether the adverse-event zeros represent collected surveillance, unavailable data encoded as zero, or another reporting convention. The record therefore cannot support a conclusion about comparative safety.
The record lists one outcome measure and no analyses. It does not report estimates, uncertainty intervals, significance tests, or analysis populations. The sample-size assumptions describe planning illustrations based on an observed effect and specify a two-sided significance level of 0.05, equal allocation, and a normal approximation. But the clinical outcome data and effect estimate needed to interpret such an illustration are not reported in the registry record. No calculated planning result can be treated as evidence about this trial’s observed effect.
Overall, the available information supports description of the trial’s question and design, along with the reason its outcome results are unavailable. It does not support a judgment that either regimen had better or worse progression-free survival, nor does it quantify uncertainty about such a comparison.
9. Statistical Methods Explained
What does randomization contribute?
In general, random allocation is intended to make treatment assignment independent of participants’ prognostic characteristics, apart from chance. This can reduce systematic differences between comparison groups and supports a causal interpretation when the allocation process is properly implemented and follow-up and analysis preserve the randomized comparison. The registry identifies the study as randomized and parallel, but does not report the sequence-generation method, allocation concealment, or the details of implementation. The presence of a randomized label alone does not establish that all those procedures were adequate.
What does single masking mean for interpretation?
The registry records single masking. In general, masking is used to limit the influence of treatment knowledge on care, assessment, or reporting. The record does not say who was masked, whether masking continued throughout follow-up, or how the different regimens were managed to support masking. Those details matter especially when an endpoint depends on assessment decisions. The registry designation therefore describes the recorded design feature without explaining its practical scope.
How is a time-to-event outcome commonly analyzed?
In general, time-to-event analyses use both the time until an event and information from participants who have not experienced the event by the end of their observed follow-up. Those participants are often described as censored; censoring is not itself an event. Kaplan–Meier methods can describe the estimated probability of remaining event-free over time, while a log-rank test can compare event-time patterns between groups. A Cox model can estimate a hazard ratio, subject to its assumptions. These are general methods, not methods confirmed for this trial: the statistical analysis plan and methods used are not reported in the registry record.
A hazard ratio, when used, compares event rates over follow-up under the model’s assumptions; it is not the same as a difference in the proportion event-free at a particular time. A confidence interval expresses uncertainty around an estimate under the chosen statistical procedure and assumptions. Without a reported estimate, interval, event count, or analysis description, neither the magnitude nor precision of this trial’s endpoint comparison can be assessed. The One Year timeframe identifies the stated outcome horizon but does not itself provide a one-year survival estimate.
Why do endpoint definitions and follow-up rules matter?
For a time-to-event endpoint, the event definition determines which observations count as events. The time origin determines when follow-up begins, and censoring rules determine how incomplete observation is represented. Assessment timing can also influence when progression is detected. These choices affect the data entering the analysis and the interpretation of an estimated treatment effect. The registry record does not report these operational details for progression-free survival, nor does it describe the follow-up schedule or handling of missing assessments.
What is the role of the stated planning assumptions?
The record describes a sample-size planning illustration using a two-sided significance level of 0.05, equal allocation between the arms, and a normal approximation. It says the target effect is expressed as a fraction of the observed effect, and that time-to-event illustrations use a total event count, whereas other illustrations use participants per arm. These are planning conventions, not observed trial outcomes. The record does not report the statistical plan used to design the study, and the progression-free-survival results needed to establish an observed effect are unavailable. A planning illustration based on an effect cannot substitute for an observed treatment comparison, and it should not be described as observed power.
Why can’t a re-analysis recover the missing result?
A re-analysis requires enough underlying information to calculate or verify an estimate. For a time-to-event outcome, that would generally include event times or suitably detailed group-level outcome summaries, follow-up information, and an analysis definition. The registry says progression-free-survival data were not collected and results could not be retained. It provides no outcome analyses. There is therefore no reported estimate to recalculate and no basis in the registry record for reconstructing the treatment comparison from the design description alone.
More broadly, sound interpretation depends on both design and outcome information. Randomization describes how groups were intended to be formed; it does not supply the missing event data. A stated endpoint identifies what investigators intended to measure; it does not establish what was observed. The available record supports discussion of the planned comparison and general statistical concepts, but not a trial-specific estimate of efficacy or safety.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies progression-free survival as the primary outcome, with One Year as its timeframe, and lists one outcome measure. It lists no analyses. The statistical plan is not reported in the registry record, so it is not possible to determine whether the investigators planned multiple tests, subgroup analyses, repeated endpoint assessments, or any adjustment for multiplicity. Multiplicity matters in general when several comparisons or outcomes are examined, because it can affect how often an apparently unusual result arises by chance. No trial-specific adjustment procedure can be described from this record.
The record’s outcome population text says data were not collected and that results could not be retained. It does not describe missing-data procedures, censoring rules, or how participants with incomplete follow-up would have been handled. Enrollment is recorded as 7, but the number with outcome information, the group-specific analysis counts, and the populations used for analysis are not reported in the registry record. The record also does not specify whether an intention-to-treat, per-protocol, or other analysis population was planned or used.
These omissions are distinct from a reported estimate with a wide confidence interval: there is no estimate or interval to evaluate. Nor should the zero adverse-event entries be interpreted as a missing-data method or as evidence of no events. The registry record does not explain their meaning. With no retained primary outcome data and no reported analysis, neither the impact of missingness nor the robustness of any comparison can be assessed.
11. What the Result Does, and Does Not, Mean
The record establishes that a randomized phase 2 trial was intended to compare two chemotherapy regimens in a population described as having recurrent platinum-resistant or refractory ovarian and peritoneal carcinoma after paclitaxel pretreatment. It also records the outcome of interest, progression-free survival at One Year, and describes the main components of each regimen. These registry entries identify the clinical question and the broad design.
They do not establish the comparative result. The registry record states that progression-free-survival data were not collected and that results could not be retained. It reports no effect estimate, uncertainty interval, test result, or analysis. It is therefore not possible to infer whether the regimens differed, how large a difference might have been, or how precisely a difference was estimated. The absence of a reported result is not evidence of no difference.
The same caution applies to safety. Although the record contains zero entries for listed adverse-event counts and deaths in both groups, it does not explain those entries, and the outcome text reports that data were not collected. Those zeros cannot be treated as confirmation that no adverse events or deaths occurred.
In general, trial conclusions depend on outcome data, definitions, follow-up, and analysis—not only on randomization or the intended endpoint. Here, the design information remains informative as a description of what was planned, while the unavailable results prevent evaluation of the primary comparison. The registry record should therefore be read as documentation of a terminated study with an unresolved outcome question, not as evidence for or against either regimen.
12. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the difference between a clearly stated comparative question and an answer supported by analyzable data. The record identifies randomization, a parallel design, two regimens, and progression-free survival as the primary outcome. Those features describe an intended framework for comparing outcomes, but they cannot produce a treatment-effect estimate when the endpoint data are unavailable.
The record also shows why outcome availability is part of evidence quality. Enrollment is recorded as 7, while the primary outcome text says data were not collected and the results could not be retained. Without group-specific outcome information, an analyst cannot assess event patterns, quantify uncertainty, or check whether the planned comparison was carried out as intended. The design label cannot resolve that limitation.
From a statistical perspective, this is not a case where an imprecise estimate can be weighed against a more precise one. No primary estimate is reported. The distinction matters: imprecision can be described using an estimate and its uncertainty, whereas unavailable data leave the treatment comparison unevaluated in the registry record. The zero adverse-event entries also illustrate how counts should be interpreted in context rather than as self-explanatory evidence.
The record is therefore useful for understanding how a randomized oncology study was framed and why its intended endpoint cannot be interpreted from the posted results. It underscores that transparent reporting of outcome definitions, analysis populations, missing data, and statistical methods is necessary for readers to assess a trial, while also making clear that such details cannot recover results that were not retained.
13. 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 principal limitation is the absence of the primary outcome data. The registry record explicitly states that data were not collected and results could not be retained after the study was terminated. No progression-free-survival estimate, event information, confidence interval, or analysis is reported. The intended comparison therefore cannot be evaluated statistically from this record.
The recorded enrollment is 7, but group-specific enrollment and outcome-analysis counts are not reported in the registry record. Participant characteristics, eligibility details beyond the broad disease description, and the extent of follow-up are also not given. Without these details, it is not possible to assess who was represented in the enrolled population or how much outcome information would have been available.
Important aspects of endpoint implementation are absent: the progression definition, time origin, assessment schedule, follow-up rules, and handling of censoring or missing assessments are not reported. The registry identifies the design as single-masked but does not state who was masked or how masking was maintained. It also does not report allocation procedures, the statistical analysis plan, the analysis population, or multiplicity procedures.
The adverse-event entries show zero counts, but their interpretation is unclear in light of the statement that data were not collected. They cannot be used to establish the absence of harms. The record’s planning assumptions do not address these limitations, because a planning illustration is not an observed outcome analysis. Together, these gaps limit interpretation to the trial’s stated design and the documented reason that results are unavailable.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: (PGA) for Platinum-resistant/Refractory, Paclitaxel-Pretreated Recurrent Ovarian and Peritoneal Carcinoma — NCT01936974.
- Registry record last updated 2018-02-20; status last verified 2018-01.
- Results first posted 2017-10-25.
- 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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17. Record Summary
NCT01936974 is recorded as a randomized, single-masked, parallel phase 2 study sponsored by Western Regional Medical Center. It compared platinum, gemcitabine and bevacizumab with gemcitabine and bevacizumab for recurrent platinum-resistant or refractory ovarian and peritoneal carcinoma in a paclitaxel-pretreated population. The registry lists fallopian tube carcinoma among the conditions and records enrollment of 7.
The primary outcome was progression-free survival at One Year. The recorded start was 2013-09, primary completion was 2015-08, and status is TERMINATED. The registry states that data were not collected because the principal investigator was no longer employed at CTCA and did not have rights to the trial information; it further states that results could not be retained. One outcome measure and no analyses are listed. The record describes the planned comparison, but does not provide results that permit evaluation of progression-free survival or comparative safety.