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 Bevacizumab and Erlotinib Study in Advanced Ovarian Cancer (NCT00130520), a non-randomized phase 2 study. The primary outcome is Objective Response (Complete Partial, Stable and Progression).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00130520 |
| Phase | Phase 2 |
| Condition | Ovarian Neoplasms |
| Allocation | Non-Randomized |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 40 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Arizona |
| Results posted | Yes |
2. Clinical Question
Population
Women with advanced ovarian cancer whose disease had progressed during prior standard chemotherapy with a taxane and a platinum. The registry record describes the primary analysis population as subjects who received 1 dose of intervention and had one post-baseline assessment; one subject was not evaluable.
Intervention
The combination of bevacizumab and erlotinib, studied in an open-label phase II trial. The registry identifies both agents as drug interventions.
Comparator
There was no randomized control group. The registry lists a single group and non-randomized allocation, so the study does not provide a like-for-like comparison against another treatment or control condition.
Primary question
The stated primary outcome is objective response, classified using standard RECIST criteria. The registry record does not report the observed numbers in the response categories, so it does not establish how participants were distributed among complete response, partial response, stable disease, or progression.
The clinical question concerns whether this drug combination warrants further study in a population with advanced ovarian cancer after progression on prior taxane- and platinum-based chemotherapy. The record describes the project as evaluating safety and effectiveness, but its design is a single-group phase II study rather than a randomized comparison. Therefore, its central evidence is descriptive: outcomes observed while participants received the combination, not an estimate of how outcomes compare with an alternative.
Objective response was defined through changes in target lesions. Complete response required disappearance of all target lesions; partial response required a 30% decrease in the sum of their longest diameters; progression required a 20% increase; and stable disease described changes that did not meet those criteria. The title of the primary outcome also names complete response, partial response, stable disease, and progression. The registry record does not report the observed category counts or an analysis estimate for this endpoint.
3. Trial Design
This was a phase II, open-label, non-randomized, single-group trial sponsored by the University of Arizona. The registry lists an enrollment of 40 and identifies bevacizumab and erlotinib as the interventions. With no random allocation and no separate comparator group, the design cannot support a randomized treatment contrast. Its results, when reported, describe outcomes in the treated group.
The registry describes the intended population as women with advanced ovarian cancer whose disease progressed while on prior standard chemotherapy with a taxane, such as paclitaxel or docetaxel, and a platinum, such as cisplatin or carboplatin. The primary endpoint population is narrower in operational terms: subjects had to receive 1 dose of intervention and complete one assessment after baseline. The record notes that one subject was not evaluable, but does not give further detail about that participant's outcome or reason for non-evaluability.
The primary outcome is titled Objective Response (Complete Partial, Stable and Progression), with a timeframe of 06.16.201 to 10.5.201. The registry's description gives RECIST-based definitions for complete response, partial response, progressive disease, and stable disease. Progression-free survival is listed as a secondary outcome. Although the registry records 3 outcome measures, it records 0 analyses; no observed result for objective response or progression-free survival is stated in the record.
The record describes an accrual decision rule: an initial accrual of 20, with closure if ≤1 confirmed responses were observed, and 20 additional participants if ≥2 responses were observed. This is a design feature stated in the registry, not an observed result. A fuller prospective statistical plan, including how the response analysis would be conducted, is not reported in the registry record. The registry lists the study as completed, with primary completion in 2010-01.
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.
Before assignment: The study had no pre-assignment criteria. This was an open label study and all subjects were given the same treatment.
Overall Study
| Stage | Bevacizumab and Erlotinib |
|---|---|
| STARTED | 40 |
| Completion of at Least One Cycle | 39 |
| COMPLETED | 1 |
| NOT COMPLETED | 39 |
Reasons for not completing this period:
| Reason | Bevacizumab and Erlotinib |
|---|---|
| Adverse Event | 11 |
| Death | 1 |
| Physician Decision | 1 |
| Withdrawal by Subject | 1 |
| Disease Progression | 23 |
| Protocol non-compliance | 1 |
| Did not meet re-treatment criteria | 1 |
Analysis population for the primary outcome, as defined in the registry: Population=subjects receiving 1 dose of intervention and one assessment post-baseline. One subject=not evaluable. Analysis-Enroll 40, initial accrual of 20. If ≤1 confirmed responses observed in 20=closure. If ≥2 responses=20 additional.
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 | Bevacizumab and Erlotinib |
|---|---|---|
| Participants analysed | 40 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 30 |
| Age, Categorical: >=65 years | Participants | 10 |
| Age Continuous | years | 59.35 (SD 11.07) |
| Sex: Female, Male: Female | Participants | 40 |
| Sex: Female, Male: Male | Participants | 0 |
| Region of Enrollment: United States | participants | 40 |
6. Primary Endpoint
The registry lists the primary outcome as Objective Response (Complete Partial, Stable and Progression), measured over 06.16.2005 to 10.05.2009.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is titled Objective Response (Complete Partial, Stable and Progression) and is measured in participants. The registry says response was assessed using standard RECIST criteria. These criteria classify changes in target lesions: complete response means disappearance of all target lesions; partial response means a 30% decrease in the sum of the longest diameter of target lesions; progressive disease means a 20% increase; and stable disease means changes that do not meet the stated thresholds for partial response or progression.
As a general statistical concept, a response endpoint converts assessments of tumor change into categories that can be counted. Such categories can give a concise description of observed disease status over a specified assessment period. They do not, by themselves, describe how long a response lasts, and a category count does not establish what would have happened under a different treatment. The listed secondary outcome, progression-free survival, concerns a time-to-event outcome and addresses a different aspect of disease course.
The registry specifies the primary-outcome timeframe as 06.16.201 to 10.5.201 and defines the analysis population as subjects receiving 1 dose of intervention and one post-baseline assessment. It notes one subject was not evaluable. However, the registry record does not give the observed participant counts in the response categories, nor does it report a summary estimate or uncertainty interval for the endpoint. Consequently, the endpoint's definition is available, but its observed distribution is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The record identifies a completed, single-group phase II study of bevacizumab and erlotinib in advanced ovarian cancer. Its primary endpoint is an objective-response classification based on RECIST criteria. These design and endpoint details establish what the study set out to describe, but they do not provide the result itself: the registry record does not report response counts, an estimated response rate, or an uncertainty interval. No conclusion about the observed objective-response outcome can be drawn from the endpoint definition alone.
The registry's accrual rule indicates that the study began with an initial accrual of 20 and could close if ≤1 confirmed responses were observed; if ≥2 responses were observed, 20 additional participants were to be accrued. This describes a decision rule, not evidence that either condition occurred. The record does not state whether the trial stopped after the initial accrual or proceeded to the additional accrual. Enrollment is listed as 40, but that value alone does not establish how many participants were evaluable for the primary outcome or how many had each response category.
The single-group design limits interpretation. Without a randomized comparator, outcomes cannot be separated from the course of disease, participant selection, prior treatment history, assessment timing, or other factors that could influence observed response. This is a general limitation of uncontrolled studies, not evidence that any particular factor affected this trial. Open-label conduct also means treatment assignment was not masked; the registry lists masking as none. The record does not describe safeguards or procedures that might have been used in assessment.
Progression-free survival appears as a secondary outcome, but no result for it is stated. The registry records 3 outcome measures and 0 analyses. It does not provide an analysis plan, estimates, or uncertainty measures for the listed outcomes. The absence of a reported result is not the same as a finding of no effect or no events; it means the registry record does not present the outcome data needed to assess the result.
Safety information is recorded separately. The adverse-event fields indicate serious events among participants at risk, and the record lists serious-event terms with percentages. Those entries are useful as descriptive safety reporting, but in the absence of a control group they do not provide comparative risk estimates. The record also does not report a death count in the group-level deaths field. A term labeled Death in the serious-event list should therefore be read as a listed event term, not as a complete mortality analysis.
In general, estimates are easier to interpret when accompanied by uncertainty intervals, analysis populations, and explicit methods for handling incomplete assessments. Those details are not reported in the registry record. The available information supports a description of design, definitions, and selected safety entries; it does not support a quantitative conclusion about efficacy or a comparative benefit-risk judgment.
9. Statistical Methods Explained
The registry record gives the study design and outcome definitions but does not report a full statistical analysis plan. The concepts below explain how such information is generally interpreted; they are not claims about additional methods used in this trial.
What does a single-group design estimate?
In a single-group study, the observed outcomes describe the participants who received the intervention. For a binary endpoint such as a response category, an analysis may report the count in each category and a proportion within a clearly defined analysis population. A comparison with another treatment requires a suitable comparator and a design that supports that comparison. Here, the registry identifies the model as single group and allocation as non-randomized, so there is no randomized treatment contrast.
General statistical interpretation distinguishes an observed outcome from a causal treatment effect. A response observed after treatment is a description of what happened in the enrolled group. It does not by itself indicate what would have happened to those same participants under another treatment or no treatment. Disease history, eligibility, prior therapies, and the timing and completeness of assessments can all matter when interpreting an uncontrolled result. The registry record does not provide enough detail to quantify those influences.
How do response categories work?
The record describes objective response using RECIST and gives definitions for complete response, partial response, progressive disease, and stable disease. In general, a categorical endpoint assigns each evaluable participant to a defined status according to assessment rules. Those definitions make the outcome interpretable only when the assessment schedule, evaluation rules, and analysis population are also clear. The registry states that the primary population received 1 dose and had one post-baseline assessment; it also notes one subject was not evaluable. It does not report the category counts or explain the reason for non-evaluability.
The endpoint title includes complete response, partial response, stable disease, and progression. The record's definitions distinguish the categories, but the wording alone does not establish how categories were combined in any analysis. The registry record does not report an observed primary result or analysis details that resolve this question. A reader should not infer an overall response count from the definitions or the accrual rule.
What does uncertainty add?
As a general concept, a confidence interval describes a range of values compatible with the observed data under a specified statistical model and method. It communicates precision as well as the central estimate. A narrow interval generally indicates greater precision than a wide interval, while neither width nor the estimate alone establishes causation in a single-group study. The registry record does not state a response estimate or confidence interval for the primary endpoint.
For time-to-event outcomes such as progression-free survival, general analyses may account for the timing of events and for participants who have not experienced an event by the end of observation. Interpretation depends on how events and censoring are defined and on the follow-up information available. Progression-free survival is listed as a secondary outcome, but its analysis details and results are not reported in the registry record.
What can the accrual rule tell us?
The registry describes an initial accrual of 20 and a rule based on confirmed responses: closure if ≤1 were observed, with 20 additional participants if ≥2 were observed. In general, such a rule can specify how a study proceeds based on accumulating outcome information. It does not itself provide the final response count or show whether the additional accrual condition was met. The record does not state which path occurred. The listed enrollment of 40 does not substitute for a reported endpoint analysis.
The separate planning assumptions describe sample-size illustrations based on an observed effect, with two-sided significance level 0.05, equal allocation between two arms, and a normal approximation. These are planning illustrations, not the trial's own design or observed power. The trial itself is listed as single group, so an equal-allocation two-arm illustration is not a description of its design. The registry does not report the underlying effect estimate or numerical planning results in the information available for this interpretation.
Why does over-dispersion matter in general?
Over-dispersion is a general issue when observed variability exceeds what a statistical model assumes. If a model understates variability, standard errors and uncertainty intervals can be too optimistic. Whether over-dispersion is relevant depends on the outcome and analysis model. The registry record does not identify a model for the primary endpoint or report a diagnostic assessment, so no claim can be made about over-dispersion in this trial.
How should the absence of analyses be read?
The registry lists 0 analyses and does not report primary outcome counts, estimates, or uncertainty intervals. This means the registry record does not permit verification of the outcome calculation or an assessment of statistical precision. It does not establish that no analysis was conducted outside the registry record. The appropriate interpretation is limited to what the record reports: the study design, outcome definitions, accrual rule, and selected safety entries.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 3 outcome measures and identifies objective response as the primary outcome and progression-free survival as a secondary outcome. It does not report a multiplicity strategy, such as whether the interpretation of multiple outcomes was adjusted or whether any outcomes were designated for separate confirmatory testing. That information is not reported in the registry record. In general, when several outcomes are examined, the chance of finding an apparently notable result among them can depend on how many tests are conducted and how they are interpreted. No trial-specific multiplicity procedure can be inferred from the record.
Missing-data handling is also not reported in the registry record. The primary endpoint population is described as participants who received 1 dose and completed one assessment after baseline, and one subject is identified as not evaluable. The registry does not state why that participant was not evaluable, whether any other assessments were incomplete, or how incomplete or unavailable outcomes were treated. It does not report imputation, sensitivity analyses, or alternative analysis populations.
As a general statistical principle, the analysis population and missing-data approach can influence an endpoint summary. Excluding participants without an evaluable assessment may yield a result that describes only those assessed, while other approaches may make different assumptions about unobserved outcomes. Without the outcome counts and analysis methods, the impact of non-evaluability cannot be assessed. The record's stated population definition should therefore be kept distinct from any broader interpretation of all enrolled participants.
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 |
|---|---|---|---|
| Bevacizumab and Erlotinib | 12 | 40 | 30.0% |
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 |
|---|---|
| Bevacizumab and Erlotinib | 40 of 40 |
Most frequent serious adverse event terms
| Event term | Organ system | Bevacizumab and Erlotinib |
|---|---|---|
| Hospitalization for dyspnea and fatigue | General disorders | 1 of 40 |
| hospitalization for diarrhea, nausea, vomiting and facial rash (CTCAE grade 2) | General disorders | 1 of 40 |
| Hospitalization for partial bowel obstruction | Gastrointestinal disorders | 1 of 40 |
| Hospitalizaton for diarrhea, abdomianl bloating, dyspnea | General disorders | 1 of 40 |
| Death | General disorders | 1 of 40 |
| Myocardial infarct | Cardiac disorders | 1 of 40 |
| Bowel perforation-large intestine | Gastrointestinal disorders | 1 of 40 |
| Possible Myocardial infarction | Cardiac disorders | 1 of 40 |
| Abdominal fistula | Cardiac disorders | 1 of 40 |
| Nasal septal perforation | General disorders | 1 of 40 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Bevacizumab and Erlotinib |
|---|---|---|
| Diarrhea | Gastrointestinal disorders | 33 of 40 |
| Rash: acne/acneiform | Skin and subcutaneous tissue disorders | 31 of 40 |
| Albumin, serum-low (hypoalbuminemia) | Metabolism and nutrition disorders | 27 of 40 |
| Pain | General disorders | 21 of 40 |
| Dry Skin | Skin and subcutaneous tissue disorders | 18 of 40 |
| Fatigue | General disorders | 16 of 40 |
| Nausea | Gastrointestinal disorders | 16 of 40 |
| Anorexia | Gastrointestinal disorders | 15 of 40 |
| Vomiting | Gastrointestinal disorders | 14 of 40 |
| Dermatology/Skin - Other | Skin and subcutaneous tissue disorders | 13 of 40 |
Serious events with the highest arm-level rate: hospitalization for dyspnea and fatigue (2.5%), hospitalization for diarrhea, nausea, vomiting and facial rash (ctcae grade 2) (2.5%), hospitalization for partial bowel obstruction (2.5%), hospitalizaton for diarrhea, abdomianl bloating, dyspnea (2.5%), death (2.5%).
The serious adverse-event fields list 40 participants at risk and 12 affected in the group receiving bevacizumab and erlotinib. The other adverse-event fields list 40 at risk and 40 affected. These are descriptive entries for the single study group, not comparisons with a control group. The deaths field is null, so a group-level death count is not reported in the registry record.
The serious-event terms listed include hospitalization for dyspnea and fatigue, hospitalization for diarrhea, nausea, vomiting and facial rash (CTCAE grade 2), hospitalization for partial bowel obstruction, hospitalization for diarrhea, abdominal bloating and dyspnea, Death, and myocardial infarct. Each listed term is accompanied by 2.5%. The registry's wording includes spelling variations in some entries. These terms should be read as the events recorded in the listing, not as a complete account of all safety outcomes or an estimate of comparative risk.
In general, adverse-event frequencies depend on definitions, reporting rules, observation time, and the population assessed. The record does not provide enough detail to determine whether events were judged related to treatment or to compare risk against another group. The listed Death term does not replace the missing group-level deaths count or establish a full mortality result.
12. What the Result Does, and Does Not, Mean
The record establishes that a completed, open-label phase II study evaluated bevacizumab and erlotinib in a single group of women with advanced ovarian cancer after progression during prior taxane- and platinum-based chemotherapy. It defines an objective-response endpoint using RECIST criteria and lists progression-free survival as a secondary outcome. It also records an accrual decision rule and selected serious adverse-event information.
These details do not establish the observed primary endpoint result. The registry record does not report how many participants had complete response, partial response, stable disease, or progression, nor does it report an estimate or confidence interval. The listed outcome definition and enrollment value cannot be used to reconstruct the missing response data. The record also does not report a progression-free survival result.
Because the study had no randomized comparator, even a reported outcome summary would describe what occurred in the treated group rather than provide a controlled estimate of the effect relative to another treatment. This is a general design limitation, not a claim about the direction or size of any outcome. Open-label conduct and the defined evaluability criteria are also relevant to interpretation, while details of assessment procedures and missing-data handling are not reported in the registry record.
The safety entries are descriptive. Serious adverse events are reported for the group, and several event terms are listed with percentages, but the record does not provide a comparative safety analysis. The group-level deaths field is null. Accordingly, the registry record supports neither a complete mortality summary nor a comparative assessment of safety.
The most defensible reading is therefore narrow: the record documents the study's design, intended population, outcome definitions, enrollment, and selected safety reporting, but does not present the primary or secondary efficacy results needed to assess the observed outcomes. Absence of reported outcome results should not be interpreted as evidence of no response, no progression, or no treatment effect.
13. Why This Trial Matters Statistically
This trial is statistically informative as an example of how design and reporting determine what a result can mean. It is a phase II study with a single group, non-randomized allocation, and no masking. Those features make clear that the study is not a randomized comparison, so its results would be descriptive of the participants receiving the combination rather than a direct estimate against a control group.
The registry also illustrates why outcome definitions and outcome results are separate pieces of evidence. The primary endpoint is described in detail through RECIST categories and lesion-change thresholds. Yet the registry record does not report the participant counts in those categories or an estimate of objective response. A precise endpoint definition cannot substitute for observed data, and an accrual rule cannot be treated as a final result.
The stated population definition matters as well. The primary analysis was to include subjects who received 1 dose and had one post-baseline assessment, with one subject noted as not evaluable. Without a reported outcome distribution or an explanation of non-evaluability, readers cannot assess how the analysis population relates to enrollment or how missing assessments may have affected interpretation.
Finally, the safety entries show the difference between event reporting and comparative inference. The record lists serious adverse-event counts and event terms, but no control group is available for a treatment comparison, and the group-level deaths field is null. The trial therefore highlights a general principle of biostatistics: design, endpoint definitions, analysis populations, uncertainty, and transparent outcome reporting all shape the strength and scope of conclusions. In this record, the design and definitions are available, while the primary outcome results and analysis details are not reported in the registry 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.
Several trial-specific limitations follow directly from the registry record. The study is listed as non-randomized, open-label, and single-group, with no like-for-like control comparison. As a result, the record cannot support a randomized estimate contrasting the combination with another treatment. Any outcomes reported from this design would be descriptive and would not, by themselves, distinguish treatment effects from other influences on observed disease course.
The primary endpoint is defined, but its observed result is not reported in the registry record. The record gives no category counts, response estimate, or uncertainty interval. It also lists progression-free survival as a secondary outcome without reporting a result. This prevents assessment of the magnitude and precision of either efficacy outcome from the registry information.
The primary analysis population requires receipt of 1 dose and one post-baseline assessment, and one subject is noted as not evaluable. The reason for non-evaluability, handling of missing assessments, and relationship between the defined analysis population and the listed enrollment are not reported in the registry record. The record also does not provide the statistical analysis plan, an approach to multiplicity, or details of how response categories were combined for analysis.
Safety interpretation is limited by the absence of a comparator and by the lack of a reported group-level deaths count. Serious-event terms and percentages are listed, but the record does not describe event attribution or provide a comparative safety estimate. These limitations do not establish that the trial lacked analyses or that any particular outcome occurred; they describe what cannot be assessed from the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Bevacizumab and Erlotinib Study in Advanced Ovarian Cancer — NCT00130520.
- Registry record last updated 2012-05-28; status last verified 2010-12.
- Results first posted 2010-12-14.
- 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, open-label, non-randomized, single-group study sponsored by the University of Arizona. It lists enrollment of 40 and evaluates bevacizumab with erlotinib in women with advanced ovarian cancer whose disease had progressed during prior taxane- and platinum-based chemotherapy.
The primary outcome is objective response, defined using RECIST categories, with a stated timeframe of 06.16.201 to 10.5.201. Progression-free survival is listed as a secondary outcome. The record describes an initial accrual of 20 and a response-based rule for closure or further accrual. It lists 3 outcome measures and 0 analyses.
The registry record does not report observed primary or secondary efficacy results. It does report selected serious adverse-event information, while the group-level deaths field is null. Missing-data methods, multiplicity procedures, and fuller analysis details are not reported in the registry record.