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 Eloxatin® Plus Gemcitabine Chemotherapy for Mesothelioma (NCT00859469), a na phase 2 study. The primary outcome is Best Response.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00859469 |
| Phase | Phase 2 |
| Condition | Mesothelioma |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 29 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Columbia University |
| Results posted | Yes |
2. Clinical Question
Population
Patients with malignant pleural or peritoneal mesothelioma were the intended population. The official title describes treatment in the first- or second-line setting. The registry record does not report detailed eligibility criteria or participant characteristics, so the extent to which the enrolled group represents a broader clinical population cannot be assessed from this record.
Intervention
The regimen combined gemcitabine and oxaliplatin, also identified as Eloxatin. The listed schedule is gemcitabine 1000 mg/m² by intravenous infusion over 90 minutes, followed by oxaliplatin 100 mg/m² by intravenous infusion over 2 hours, repeated for 14 days up to 6 cycles.
Comparator
There was no separate comparator group in the registry description. The study is identified as single-group, with allocation listed as not applicable and no masking. The response assessment compares radiologic status with baseline; that within-participant comparison is not a randomized comparison between treatments.
Primary question
The primary question was how many participants had each best-response category after treatment, using radiologic assessment by RECIST criteria at 2 months. The registry describes rules for assigning complete response, partial response, and stable/no response, but numerical category counts or a response rate are not reported in the registry record.
3. Trial Design
This was a phase II clinical trial with a single-group design. The registry lists enrollment of 29 and marks the study completed. Allocation is listed as not applicable, and masking as none. These features mean the registry does not describe a randomized, masked comparison with a concurrent control group. The treatment group is listed as Oxaliplatin and Gemcitabine.
The official title identifies patients with malignant pleural or peritoneal mesothelioma receiving first- or second-line chemotherapy. The registry’s condition field is Mesothelioma. Detailed eligibility criteria, baseline characteristics, and the distribution of participants by disease site or treatment line are not reported in the registry record. The extent to which participants differed in these respects therefore cannot be assessed from the record.
The listed regimen was gemcitabine 1000 mg/m² by intravenous infusion over 90 minutes, then oxaliplatin 100 mg/m² by intravenous infusion over 2 hours, repeated for 14 days up to 6 cycles. The registry does not provide further operational details about treatment delivery, dose changes, or adherence. Such details should not be inferred from the listed schedule.
The study start is recorded as 2004-04 and primary completion as 2009-03. Columbia University is named as sponsor. Overall survival and progression-free survival are listed as secondary outcomes, in addition to the primary best-response outcome. Numerical results for these outcomes are not reported in the registry record. The record lists no analyses, so it does not provide a statistical comparison or a detailed account of how the outcome data were analyzed.
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: Patients who are deemed eligible will start the treatment cycle, defined as an interval of 14 days, and comprising of treatment with Gemcitabine followed immediately by Oxaliplatin.
Overall Study
| Stage | Oxaliplatin and Gemcitabine |
|---|---|
| STARTED | 29 |
| 6 Cycles | 16 |
| COMPLETED | 1 |
| NOT COMPLETED | 28 |
Reasons for not completing this period:
| Reason | Oxaliplatin and Gemcitabine |
|---|---|
| Adverse Event | 2 |
| Lack of Efficacy | 9 |
| Withdrawal by Subject | 1 |
| Death | 16 |
Analysis population for the primary outcome, as defined in the registry: intention to treat principle
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 | Oxaliplatin and Gemcitabine |
|---|---|---|
| Participants analysed | 29 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 16 |
| Age, Categorical: >=65 years | Participants | 13 |
| Age, Continuous | years | 63.0 (SD 11.5) |
| Sex: Female, Male: Female | Participants | 9 |
| Sex: Female, Male: Male | Participants | 20 |
| Region of Enrollment: United States | participants | 29 |
| Primary Site: Pleural | participants | 16 |
| Primary Site: Peritoneal | participants | 13 |
| Pathologic Subtype: Epithelioid | participants | 19 |
| Pathologic Subtype: Sarcomatoid | participants | 3 |
| Pathologic Subtype: Biphasic | participants | 7 |
| Prior chemotherapy regimens: 0 | participants | 11 |
| Prior chemotherapy regimens: 1 or more | participants | 18 |
6. Primary Endpoint
The registry lists the primary outcome as Best Response, measured over Two months.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is Best Response, measured as the number of participants in response categories. The stated assessment is radiologic response by RECIST criteria, comparing baseline with assessment at 2 months. The registry specifies that a best response of complete response requires two objective determinations of CR before progression. A best response of partial response requires two determinations of PR or better before progression, without meeting the CR rule. Stable/no response requires two determinations of stable/no response or better before progression, without meeting the CR or PR rules.
In general, a best-response endpoint condenses assessments over a defined period into a category for each participant. This can make the pattern of radiologic response easier to describe than a sequence of individual assessments. The category rules matter: they determine which observations count as a response and require repeated determinations rather than relying on a single scan. Those rules do not, by themselves, show how many participants entered each category.
The registry identifies the intention-to-treat principle as the population approach. However, response counts, the denominator used for any response-rate calculation, and the handling of missing assessments are not reported in the registry record. As a result, the endpoint’s numerical estimate and its precision cannot be evaluated from the information recorded.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies the clinical question and the intended response assessment, but it does not report numerical results for Best Response. In particular, the record does not give counts in the response categories, a response rate, or a confidence interval. The primary endpoint therefore cannot be quantified from the registry record, and no conclusion about the observed magnitude or precision of response can be drawn from it.
Enrollment is listed as 29, but this figure alone does not establish the denominator for the primary endpoint. The registry does not report how many participants had an evaluable assessment, how missing or unevaluable assessments were handled, or how many participants were assigned to each best-response category. An endpoint denominator or a percentage should not be reconstructed from enrollment alone.
Design is also important to interpretation. This was a single-group study without a separate comparator group. The baseline comparison in the endpoint definition describes change in radiologic status within the treatment group; it is not a comparison of treatment effects between groups. Without a concurrent control, the record cannot isolate the contribution of the regimen from other influences on observed disease status. This is a general limitation of interpreting outcomes from a single-group design.
The registry lists overall survival and progression-free survival as secondary outcomes, but does not report their results or the details needed to interpret them. The record also lists no analyses. Thus, there is no posted inferential analysis, adjustment, or uncertainty estimate available for those outcomes in this record.
Planning illustrations based on an observed effect are not the same as observed trial results or observed power. Their stated assumptions include a two-sided significance level of 0.05, equal allocation between two hypothetical arms, and a normal approximation. Those assumptions do not change the trial’s single-group design. Without numerical outcome estimates and the corresponding planning values, the precision and practical implications of any such illustration cannot be assessed. The registry record also does not report a rationale for the enrollment target or a design-based sample-size justification.
Overall, the record supports a description of the intended population, regimen, design, and endpoint rules. It does not provide the outcome data required to estimate response, judge precision, or compare the regimen with another treatment. These are limits of the information reported, not evidence for a particular outcome.
9. Statistical Methods Explained
Statistical interpretation begins by distinguishing an endpoint definition from an endpoint result. The registry defines Best Response as a count of participants assigned to radiologic response categories. It describes the assessment at 2 months and rules for complete response, partial response, and stable/no response. Those details explain what the outcome is meant to measure; they do not supply category counts, a response proportion, or uncertainty around an estimate. Numerical primary results are not reported in the registry record.
What does a single-group design allow?
The trial is listed as single-group, with allocation not applicable and masking none. In a single-group study, outcomes can describe what happened among participants receiving the listed regimen. A comparison of status with baseline can also describe change over time within that group. In general, neither description alone establishes what would have happened to comparable participants under a different treatment or without the regimen. A concurrent comparator is needed for a direct between-group contrast, and none is recorded.
This distinction matters even when the endpoint uses a defined response framework. A clear rule for categorizing scans can improve consistency in outcome classification, but it does not remove the limitations of a non-comparative design. Interpretation also depends on who was assessed, how assessments were conducted, and how incomplete observations were handled. Those operational details are not reported in the registry record.
How should counts and rates be understood?
The primary outcome is specified as participants, with the parameter described as a number. A count reports how many participants fall into a category. A rate or proportion additionally requires a denominator and a defined rule for including participants. The record lists enrollment of 29 and identifies an intention-to-treat principle, but it does not report the response counts or the denominator used in an endpoint calculation. No response rate should therefore be inferred from enrollment.
In general, an intention-to-treat approach aims to analyze participants according to their study assignment or enrollment group, rather than excluding them simply because treatment was not completed as planned. The registry names this principle but does not describe how it was operationalized for this endpoint, including the treatment of missing scans or participants without an evaluable response. The label alone does not establish the exact denominator or missing-data method used.
What would an uncertainty interval add?
In general, a confidence interval describes the range of values compatible with an estimate under a stated statistical procedure. It helps readers distinguish an imprecise estimate from one with greater precision. It does not guarantee that the true value lies in the interval, nor does it correct for limitations in design, measurement, or missing data. The registry record does not report an interval for Best Response, so precision cannot be judged from this record.
For a single-group response proportion, uncertainty depends on both the observed count and the analysis denominator, as well as the method used to calculate the interval. Since the registry does not report those results or the method, no interval can be reconstructed without making assumptions. Reconstructing one from enrollment would risk treating all enrolled participants as having known endpoint status, which the record does not establish.
How do the planning assumptions differ from the trial design?
The registry describes planning illustrations based on a fraction of an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. These are planning assumptions, not a description of the study’s actual allocation. The trial itself is listed as single-group. The hypothetical equal-allocation framework should not be mistaken for a randomized two-arm comparison in this study.
In general, a sample-size calculation asks how many participants or events a future design might require under specified assumptions about the effect, variability, significance level, and power. Such a calculation is conditional on those assumptions; it does not show that a completed trial had that power, and it does not establish an observed treatment effect. The planning illustrations are not observed power. The registry does not report the study’s own sample-size justification, and the numerical outcome estimate and planning values are not reported in the registry record.
For time-to-event outcomes, the stated planning convention uses a total number of events; other planning displays use participants per arm. In general, event-based planning for time-to-event outcomes differs from planning based on a participant count because the information available depends on events observed. Here, overall survival and progression-free survival are listed as secondary outcomes, but their numerical results and event counts are not reported in the registry record.
Why does over-dispersion matter in general?
Over-dispersion is a general statistical issue in count data: observed variation can exceed what a simple model assumes. If a model ignores that extra variation, its uncertainty estimates may be too small and statistical tests may appear more conclusive than warranted. This is a general concept, not a reported feature of this study. The primary outcome is described as participant counts, and the registry record does not report a count model or an over-dispersion assessment. There is no basis in the record to claim that over-dispersion was tested or was present.
More broadly, a statistical method cannot compensate for unreported outcome data or a missing comparator. The registry supplies the endpoint definition and design labels, but not the numerical response results, a confidence interval, or a detailed analysis plan. Interpretation should remain limited to what those recorded details establish.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists Best Response as the primary outcome and Overall Survival and Progression-free Survival as secondary outcomes. Considering multiple outcomes raises a general multiplicity question: when several hypotheses are tested, the chance of at least one apparently notable result can increase unless the analysis plan accounts for the testing structure. The registry record does not report whether any multiplicity procedure was planned or used, or how the outcomes were ordered or interpreted statistically.
The record lists no analyses and does not provide numerical results for the primary or secondary outcomes. It also does not report interim analyses, stopping rules, or a statistical analysis plan. These details are therefore not reported in the registry record; their absence from the record should not be filled by assumptions about what investigators may have done.
The primary endpoint description identifies the intention-to-treat principle. This states the intended analysis population at a broad level, but the registry does not explain how participants without a 2-month assessment were handled, whether any observations were imputed, or how incomplete follow-up was treated. Missing-data methods and the extent of missingness are not reported in the registry record.
In general, missing outcome data can affect both the estimate and its uncertainty, particularly if the chance of missingness is related to health status or response. The record does not provide information to evaluate that possibility. It also does not report the endpoint denominator, so the relationship between enrollment and participants with an observed response assessment cannot be determined.
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 |
|---|---|---|---|
| Oxaliplatin and Gemcitabine | 11 | 28 | 39.3% |
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 |
|---|---|
| Oxaliplatin and Gemcitabine | 27 of n/a |
Most frequent serious adverse event terms
| Event term | Organ system | Oxaliplatin and Gemcitabine |
|---|---|---|
| Anemia | Blood and lymphatic system disorders | 3 of 28 |
| Elevated alkaline phosphatase | Hepatobiliary disorders | 3 of 28 |
| Leukopenia | Blood and lymphatic system disorders | 3 of 28 |
| Elevated AST | Hepatobiliary disorders | 3 of 28 |
| Elevated ALT | Hepatobiliary disorders | 3 of 28 |
| Dyspnea | Respiratory, thoracic and mediastinal disorders | 1 of 28 |
| Thrombocytopenia | Blood and lymphatic system disorders | 1 of 28 |
| Elevated Bilirubin | Hepatobiliary disorders | 1 of 28 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Oxaliplatin and Gemcitabine |
|---|---|---|
| Anemia | Blood and lymphatic system disorders | 23 of 26 |
| Thrombocytopenia | Blood and lymphatic system disorders | 16 of 28 |
| Elevated alkaline phosphatase | Hepatobiliary disorders | 15 of 26 |
| Elevated ALT | Hepatobiliary disorders | 14 of 26 |
| Elevated AST | Hepatobiliary disorders | 13 of 26 |
| Peripheral neuropathy | Nervous system disorders | 11 of 29 |
| Nausea/Vomiting | Gastrointestinal disorders | 9 of 29 |
| Leukopenia | Blood and lymphatic system disorders | 5 of 26 |
| Dyspnea | Respiratory, thoracic and mediastinal disorders | 4 of 28 |
| Diarrhea | Gastrointestinal disorders | 2 of 29 |
Serious events with the highest arm-level rate: anemia (10.7%), elevated alkaline phosphatase (10.7%), leukopenia (10.7%), elevated ast (10.7%), elevated alt (10.7%).
The registry lists serious adverse events for the Oxaliplatin and Gemcitabine group with 28 at risk and 11 affected. For other adverse events, it lists 27 affected, while the at-risk count is not reported in the registry record. These figures should be read as separate registry entries; the missing at-risk count means a proportion for other adverse events cannot be interpreted from the recorded figures. The safety counts should not be combined with the trial enrollment figure to infer a shared denominator.
The serious adverse-event terms listed most often are anemia, elevated alkaline phosphatase, leukopenia, elevated AST, and elevated ALT, each at 10.7%; dyspnea is listed at 3.6%. These are the percentages recorded for the terms. They do not establish whether an event was caused by the regimen, and the registry entry does not provide further detail about attribution or event severity beyond its serious-event classification.
In general, adverse-event counts describe events recorded under the study’s reporting rules; they do not by themselves estimate comparative risk. A control group, consistent follow-up, and clear denominators would be needed for a direct comparison of event frequencies. The registry record does not report deaths in the safety entry.
12. What the Result Does, and Does Not, Mean
The record describes a phase II, single-group evaluation of oxaliplatin plus gemcitabine in patients with malignant pleural or peritoneal mesothelioma. It identifies Best Response as the primary endpoint and gives the radiologic assessment rules and timeframe. It also lists overall survival and progression-free survival as secondary outcomes. Those details clarify what the study set out to assess.
However, the numerical results for Best Response and the secondary outcomes are not reported in the registry record. The record does not give response-category counts, an endpoint denominator, a response rate, or uncertainty intervals. It is therefore not possible to say what response pattern was observed or how precisely it was estimated from the information recorded.
The single-group design also limits the type of inference available. Without a concurrent comparator, outcomes among participants in the study cannot establish a treatment effect relative to another regimen or to no treatment. The baseline comparison described for the radiologic endpoint is not a randomized comparison. This does not make the endpoint definition meaningless; it means the results, if reported, would need to be interpreted in light of the design.
The registry’s safety entry reports serious adverse events affecting 11 participants among 28 at risk, alongside other adverse events affecting 27, for which the at-risk count is not reported. Listed serious-event percentages provide information about the recorded terms but do not, on their own, establish causation or comparative safety.
Thus, the registry record supports a description of the trial’s question, regimen, endpoint, and selected safety counts. It does not support a numerical estimate of efficacy, a comparative treatment conclusion, or a complete assessment of precision and safety. These distinctions are important: an absent result in the registry record is not the same as a result showing no response or no effect.
13. Why This Trial Matters Statistically
This trial illustrates why statistical interpretation depends on both outcome definitions and study design. The registry specifies Best Response using radiologic assessments and explicit category rules. Those rules define what would count as a response, including the requirement for repeated determinations. Clear criteria are important because outcome classification should not depend on an informal or shifting definition.
At the same time, a defined endpoint is only one part of an interpretable result. Counts, denominators, and measures of uncertainty are needed to understand the observed response pattern. They are not reported in the registry record. Without them, readers cannot assess the magnitude of the endpoint or how precisely it was estimated. Enrollment alone cannot substitute for the missing endpoint information.
The single-group design offers another useful statistical lesson. A study can describe outcomes under a regimen without providing a direct estimate of how those outcomes compare with another treatment. The distinction between within-group change and between-group treatment effect is fundamental. Here, the endpoint compares radiologic status with baseline, while the registry records no separate comparator group.
The record also shows why planning assumptions should be kept separate from completed-trial evidence. Sample-size planning illustrations use stated assumptions, including equal allocation between two arms, even though this study is recorded as single-group. Such illustrations can describe hypothetical planning scenarios, but they are not the trial’s observed power and do not replace observed results.
Finally, the safety entry highlights the importance of denominators. Serious events have a recorded at-risk count, while the at-risk count for other events is not reported. Those entries cannot be read as directly comparable rates without consistent denominators and reporting context. Together, these features make the study a useful example of how registry design fields, endpoint rules, analysis details, and numerical outcomes each contribute different information.
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 affect interpretation of the registry record. The study is listed as single-group, with allocation not applicable and no masking. There is no concurrent control group in the record, so a treatment contrast cannot be estimated from the design as described. The baseline comparison in the endpoint definition does not provide the same information as a randomized between-group comparison.
The registry identifies a population with malignant pleural or peritoneal mesothelioma and describes the treatment as first- or second-line. Detailed eligibility criteria, participant characteristics, and the distribution by disease site or treatment line are not reported in the registry record. This limits assessment of who was enrolled and how broadly the findings could be applied, even if outcome results were available.
Most importantly, numerical primary and secondary outcomes are not reported. The best-response counts, denominator, response rate, and uncertainty estimates are absent. Missing-assessment procedures and the analysis details behind the stated intention-to-treat principle are also not reported. The record lists no analyses, so it does not document how outcomes were statistically evaluated.
The safety information has its own limits. The serious-event entry gives an at-risk count of 28 and an affected count of 11, but the at-risk count for other adverse events is not reported. The record does not provide further detail about event attribution. Finally, although planning assumptions are described, the study’s own sample-size justification is not reported in the registry record. These gaps prevent a complete assessment of statistical precision, outcome handling, and comparative safety.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Eloxatin® Plus Gemcitabine Chemotherapy for Mesothelioma — NCT00859469.
- Registry record last updated 2019-10-30; status last verified 2019-10.
- Results first posted 2012-02-24.
- 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
This completed phase II study, sponsored by Columbia University, evaluated oxaliplatin plus gemcitabine in patients with malignant pleural or peritoneal mesothelioma. It is recorded as a single-group study with enrollment of 29, allocation not applicable, and no masking. The listed regimen combines intravenous gemcitabine and oxaliplatin, and the official title identifies first- or second-line chemotherapy.
The primary outcome is Best Response, assessed radiologically by RECIST criteria at 2 months, with specified rules for response categories. Overall survival and progression-free survival are listed as secondary outcomes. Numerical outcome results, response counts, and uncertainty estimates are not reported in the registry record. The safety entry lists serious adverse events affecting 11 among 28 at risk and other adverse events affecting 27, without an at-risk count for the latter. The record lists no analyses.