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 Gefitinib in Treating Patients With Stage IB, II, or IIIA Non-small Cell Lung Cancer That Was Completely Removed by Surgery (NCT00049543), a randomized phase 3 study. The primary outcome is Overall Survival.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00049543 |
| Phase | Phase 3 |
| Condition | Adenocarcinoma of the Lung, Adenosquamous Cell Lung Cancer, Bronchoalveolar Cell Lung Cancer |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 503 |
| Arms in the primary outcome | 2 |
| Lead sponsor | National Cancer Institute (NCI) |
| Results posted | Yes |
2. Clinical Question
Population
Patients with completely resected stage IB, II, or IIIA non-small cell lung cancer. The registry lists several histologic types, including adenocarcinoma, squamous cell, and large cell lung cancer. The primary outcome population is identified as the ITT population.
Intervention
Gefitinib, taken by mouth once daily for 2 years, unless disease progression or unacceptable toxicity occurred.
Comparator
Placebo, taken by mouth once daily for 2 years, unless disease progression or unacceptable toxicity occurred.
Primary question
How did overall survival compare between the gefitinib and placebo groups after surgery? Survival was assessed from randomization to death from any cause, with the 5-year survival rate reported.
The trial addressed whether assigning gefitinib after surgery was associated with a different overall-survival experience from assigning placebo. The registry describes a randomized, double-blind comparison, which is intended to reduce the influence of treatment-selection differences and expectations on the comparison. It does not establish that any observed difference was caused by treatment; interpretation also depends on the analysis, uncertainty, and completeness of outcome follow-up.
The registry record reports 503 enrolled participants and identifies overall survival as the primary outcome. The listed secondary outcomes were disease-free survival and the incidence of toxicities graded using the NCI Common Terminology Criteria for Adverse Events Version 3.0. Results for those outcomes are not detailed in the information reported for this analysis. The record also lists laboratory biomarker analysis, but does not report its specific role or findings.
3. Trial Design
This was a phase III, randomized, double-blind, parallel-group, placebo-controlled trial sponsored by the National Cancer Institute. The registry lists enrollment of 503. The trial began in 2002-09, had primary completion in 2011-04, and is marked completed.
Participants were assigned to gefitinib or placebo after complete surgical removal of primary stage IB, II, or IIIA non-small cell lung cancer. The treatment descriptions specify oral dosing once daily for 2 years, unless disease progression or unacceptable toxicity occurred. The registry lists several lung cancer histologies, including adenocarcinoma, adenosquamous cell, bronchoalveolar cell, large cell, and squamous cell lung cancer.
Double masking means that the treatment assignment was concealed from participants and relevant trial personnel as described by the registry’s design classification. The record does not identify which specific roles were masked or describe how masking was maintained. Random allocation is stated, but details of sequence generation, allocation concealment, and the allocation procedure are not reported in the registry record.
The primary outcome was overall survival in the ITT population. The registry defines the time frame as randomization until death from any cause, assessed up to 5 years, and reports the percentage alive at 5 years. Its stated analysis plan uses Kaplan-Meier methods to describe survival and a stratified log-rank test as the primary comparison, adjusting for stratification factors. An unadjusted analysis was also planned. The identities of the stratification factors and further details of the analysis plan are not reported in the registry record.
The registry lists disease-free survival and graded toxicities as secondary outcomes. It also lists laboratory biomarker analysis as an intervention. The record does not give further descriptions of the biomarker procedures or results in the material reported for this trial.
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 I (Gefitinib) | Arm II (Placebo) |
|---|---|---|
| STARTED | 251 | 252 |
| COMPLETED | 249 | 243 |
| NOT COMPLETED | 2 | 9 |
Reasons for not completing this period:
| Reason | Arm I (Gefitinib) | Arm II (Placebo) |
|---|---|---|
| still on treatment | 2 | 9 |
Analysis population for the primary outcome, as defined in the registry: ITT population
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 I (Gefitinib) | Arm II (Placebo) | Total |
|---|---|---|---|---|
| Participants analysed | 251 | 252 | 503 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 105 | 120 | 225 |
| Age, Categorical: >=65 years | Participants | 146 | 132 | 278 |
| Age, Continuous | years | 67.3 (38.9 to 88) | 65.9 (30.4 to 86.9) | 66.7 (30.4 to 88) |
| Sex: Female, Male: Female | Participants | 116 | 116 | 232 |
| Sex: Female, Male: Male | Participants | 135 | 136 | 271 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 2 | 2 | 4 |
| Race (NIH/OMB): Asian | Participants | 6 | 3 | 9 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 1 | 1 |
| Race (NIH/OMB): Black or African American | Participants | 10 | 9 | 19 |
| Race (NIH/OMB): White | Participants | 233 | 235 | 468 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 2 | 2 |
| Region of Enrollment: Canada | participants | 52 | 50 | 102 |
| Region of Enrollment: United States | participants | 199 | 202 | 401 |
6. Primary Endpoint
The registry lists the primary outcome as Overall Survival, measured over From randomization to the time of death from any cause, assessed up to 5 years.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | 95% Confidence Interval |
| Unit | percentage of 5 years survival rate |
| Endpoint classification | not reduced to a single comparison |
Overall survival measures the time from randomization until death from any cause. The registry reports the percentage of participants alive at 5 years, rather than reporting only the timing of events. The stated assessment period extends up to 5 years.
Overall survival is a time-to-event outcome: it uses information about both whether an event occurred and when it occurred. The Kaplan-Meier method, named in the registry’s analysis description, estimates survival over time while accounting for participants whose event time is not observed during follow-up. The registry says survival experience in both groups would be described this way.
This endpoint is useful for comparing the duration of survival without restricting the event definition to a particular cause of death. Here, the event is death from any cause. The registry’s primary analysis compares the groups using a stratified log-rank test, with an unadjusted analysis also planned. The 5-year survival rate provides a specific time-point summary, while the time-to-event comparison uses follow-up across the stated period.
The registry identifies the ITT population for the primary outcome. The posted 5-year estimates are 52% for gefitinib, with a 95% confidence interval from 0.44 to 0.58, and 57% for placebo, with a 95% confidence interval from 0.51 to 0.64. These estimates describe survival in the trial groups; they do not, by themselves, establish the result of the comparative test or explain why any difference occurred.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted 5-year survival estimates are 52% in the gefitinib group and 57% in the placebo group. The corresponding 95% confidence intervals are 0.44 to 0.58 and 0.51 to 0.64. These intervals communicate uncertainty around each group’s estimated survival rate. They overlap; however, overlap between separate confidence intervals is not, by itself, the formal test of a between-group difference.
The registry reports a log-rank analysis with a hazard ratio of 1.24 and a 95% confidence interval from 0.94 to 1.64, with p=0.14. The interval includes 1, the no-difference reference value for a hazard ratio, and the reported p-value is above the conventional 0.05 threshold used in the stated planning assumptions. This result does not provide clear statistical evidence of a difference in overall survival under that comparison. It also does not establish that the groups had identical survival experiences: the confidence interval leaves room for effects in either direction.
The hazard ratio summarizes relative event rates over follow-up under the assumptions of the analysis. The registry lists gefitinib and placebo as the comparison groups, but does not spell out the hazard-ratio reference convention in the result description. The estimate should therefore be read together with the registry’s group order and analysis description rather than treated as a stand-alone direction of effect. The 5-year survival percentages and the hazard ratio are different summaries: one concerns survival at a specified time point, while the other describes a relative event rate over time.
The primary analysis was described as a stratified log-rank test adjusting for stratification factors, with an unadjusted analysis also planned. The reported analysis is identified as a log-rank result. The registry record does not identify the stratification factors in the information available for interpretation, so the exact adjustment cannot be reconstructed from these details.
The reported result is about the trial’s overall-survival comparison in the ITT population. It does not resolve the findings for disease-free survival, toxicities, or biomarker analyses; those results are not detailed in the registry information. Nor does the result establish the effect for every listed cancer stage or histology separately. Subgroup-specific estimates and tests are not reported in the registry record.
Statistical uncertainty is important in reading both the survival estimates and the comparative analysis. The point estimates alone do not show how precisely the treatment groups differ. The confidence interval for the hazard ratio spans values on both sides of its no-difference reference, while the p-value does not meet the threshold stated in the planning assumptions. Taken together, the posted data do not demonstrate a statistically clear overall-survival difference, but they do not prove equivalence or rule out potentially meaningful differences.
9. Statistical Methods Explained
The registry describes Kaplan-Meier estimates, a stratified log-rank test, an unadjusted analysis, and a hazard ratio for the primary overall-survival comparison. These methods address related but distinct aspects of a time-to-event outcome.
What does the Kaplan-Meier method describe?
Kaplan-Meier estimation describes survival over follow-up. It incorporates the observed times to death and can retain information from participants whose follow-up ends before a death is observed. Such observations are censored: their complete event time is not known, but their observed follow-up still contributes information up to the point at which observation ends. This interpretation depends on assumptions about censoring and follow-up. The registry record does not report the amount or pattern of censoring, or diagnostic checks of those assumptions.
The registry also reports a 5-year survival rate. This is a time-point summary of the estimated survival curve, not a count of deaths and not the hazard ratio. The gefitinib estimate is 52%, with a 95% confidence interval from 0.44 to 0.58; the placebo estimate is 57%, with a 95% confidence interval from 0.51 to 0.64. A confidence interval conveys uncertainty in an estimate under the statistical method used. It is not a range containing a specified proportion of individual participants’ outcomes.
What does a log-rank test assess?
A log-rank test compares the event experience of groups across follow-up. The registry specifies a stratified log-rank test as the primary method and says it adjusts for stratification factors. Stratification can account for the factors used to form strata when comparing event experience. The factors themselves, and the details of how they were incorporated, are not reported in the registry record. The record says an unadjusted analysis would also be performed, but does not provide further detail about that analysis in its methods description.
The registry reports a hazard ratio of 1.24, with a 95% confidence interval from 0.94 to 1.64 and p=0.14. A hazard ratio compares event rates at a given point in follow-up, conditional on the analysis framework; it is not a ratio of the 5-year survival percentages. A value of 1 is the no-difference reference for a hazard ratio. The confidence interval includes that reference, indicating that the estimate is not precise enough to exclude it at the interval’s stated confidence level. The reported p-value is a measure of how incompatible the observed data are with the null hypothesis under the specified test, assuming the model and test conditions. It is not the probability that the null hypothesis is true.
Hazard-ratio interpretation commonly depends on whether relative hazards are sufficiently stable over time. The registry record does not report a proportional-hazards assumption assessment or a time-varying effect analysis. This omission does not show that the assumption failed; it means that its evaluation cannot be assessed from the registry description.
Why report both a rate and a time-to-event comparison?
The 5-year survival rate gives a direct estimate at a clinically specified follow-up point. The log-rank comparison uses event-time information across follow-up rather than only the status at that point. These summaries can complement each other, but they need not convey identical information. Their estimates and uncertainty should be interpreted according to the method that produced each one.
General statistical context: a non-significant test does not establish that groups are equivalent. It means the analysis did not provide sufficiently strong evidence against its null hypothesis under the chosen test and threshold. The width and placement of the confidence interval help show which effect sizes remain compatible with the data and method. Here, the reported hazard-ratio interval includes 1 and extends on either side of it.
What planning assumptions are described?
The registry’s sample-size assumptions describe planning illustrations based on the observed effect, a two-sided significance level of 0.05, equal allocation, and a normal approximation. The effect to detect is defined as a stated fraction of the observed effect. For time-to-event outcomes, the described planning quantity is the total number of events; other outcomes use participants per arm. These are planning assumptions, not observed power. A sample-size justification for the trial itself is not reported in the registry record, and no planning illustration should be interpreted as a trial result.
The record does not report detailed model diagnostics, a missing-data strategy, the treatment of protocol deviations, or a full statistical analysis plan. Those omissions limit independent assessment of implementation and robustness. They do not change the fact that the posted result is a log-rank hazard-ratio analysis accompanied by 5-year survival estimates.
10. Analyses Reported by the Sponsor
| Method | Estimate | 95% CI | P-value |
|---|---|---|---|
| Log Rank | Hazard Ratio (HR) 1.24 | 0.94 to 1.64 | 0.140 |
The registry reports the primary comparison as a log-rank hazard ratio of 1.24, with a 95% confidence interval from 0.94 to 1.64 and p=0.14. It also gives 5-year survival estimates for each group. These are the posted trial results to use when describing the sponsor’s reported analysis.
The registry record does not include a separate recalculated hazard ratio or another recalculated comparative result. A simple re-analysis from summary statistics, if performed, would not necessarily reproduce a stratified log-rank result: the reported primary analysis accounts for event times and uses stratification factors, while aggregate summaries do not preserve all of that information. The registry does not provide enough detail about those factors to reconstruct the adjusted test independently.
No discrepancy between a recalculation and the sponsor’s analysis is identified in the registry record. The reported log-rank result therefore remains the relevant comparative analysis, rather than an independently recalculated value. Its interval includes the no-difference hazard-ratio reference, and its p-value is 0.14. Those features support a cautious description: the posted analysis does not show a statistically clear overall-survival difference, while leaving uncertainty about the size and direction of the underlying effect.
11. Multiplicity, Missing Data and Analysis Populations
The registry lists overall survival as the primary outcome and identifies disease-free survival and incidence of toxicities graded using the NCI Common Terminology Criteria for Adverse Events Version 3.0 as secondary outcomes. It does not report a multiplicity adjustment, a hierarchy among outcomes, or a plan for controlling the chance of false-positive findings across multiple comparisons. Those details are not reported in the registry record.
Multiplicity matters when several outcomes, subgroups, or analyses are tested. Without a stated approach, it is difficult to know whether secondary or exploratory findings were intended to be confirmatory or how their statistical evidence should be interpreted. The primary outcome and analysis are identified, but further details about any multiple-testing strategy are not reported.
The primary outcome population is named as the ITT population. This generally refers to analyzing participants according to their randomized assignment, regardless of treatment received, but the registry does not give further implementation details. It does not report how missing outcome observations were handled, the extent of loss to follow-up, or whether sensitivity analyses were used to assess the impact of missing data. The registry record also does not specify how protocol deviations or treatment discontinuation were handled in the primary analysis.
The trial describes treatment continuation for up to 2 years unless disease progression or unacceptable toxicity occurred, while the primary survival assessment extends up to 5 years. The record does not provide details of follow-up completeness or censoring by group. Such information would help assess whether follow-up differed between groups and how much information contributed to the survival estimates.
The record lists the named secondary outcomes but does not provide their results in the information reported for this analysis. It also does not report subgroup-specific estimates, biomarker findings, or interim analyses. Their absence from the registry information should not be taken to mean that such analyses were or were not conducted; they are not reported in the registry record.
12. 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 I (Gefitinib) | 34 | 249 | 13.7% |
| Arm II (Placebo) | 43 | 243 | 17.7% |
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 |
|---|---|
| Arm I (Gefitinib) | 240 of 249 |
| Arm II (Placebo) | 226 of 243 |
Most frequent serious adverse event terms
| Event term | Organ system | Arm I (Gefitinib) | Arm II (Placebo) |
|---|---|---|---|
| Dyspnea | Respiratory, thoracic and mediastinal disorders | 10 of 249 | 14 of 243 |
| Infection - Other | Infections and infestations | 4 of 249 | 3 of 243 |
| Pneumonitis | Respiratory, thoracic and mediastinal disorders | 4 of 249 | 3 of 243 |
| Cardiac General - Other | Cardiac disorders | 2 of 249 | 4 of 243 |
| Diarrhea | Gastrointestinal disorders | 4 of 249 | 2 of 243 |
| Dehydration | Metabolism and nutrition disorders | 3 of 249 | 2 of 243 |
| Thrombosis/thrombus/embolism | Vascular disorders | 4 of 249 | 1 of 243 |
| Pain Chest/thorax NOS | General disorders | 0 of 249 | 4 of 243 |
| Mood alteration Anxiety | Psychiatric disorders | 2 of 249 | 2 of 243 |
| Nausea | Gastrointestinal disorders | 2 of 249 | 1 of 243 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Arm I (Gefitinib) | Arm II (Placebo) |
|---|---|---|---|
| Dyspnea | Respiratory, thoracic and mediastinal disorders | 130 of 249 | 147 of 243 |
| Fatigue | General disorders | 135 of 249 | 130 of 243 |
| Rash | Skin and subcutaneous tissue disorders | 167 of 249 | 66 of 243 |
| Diarrhea | Gastrointestinal disorders | 155 of 249 | 75 of 243 |
| Pain Chest/thorax NOS | General disorders | 86 of 249 | 107 of 243 |
| Dry skin | Skin and subcutaneous tissue disorders | 107 of 249 | 46 of 243 |
| Cough | Respiratory, thoracic and mediastinal disorders | 63 of 249 | 71 of 243 |
| Pruritus | Skin and subcutaneous tissue disorders | 92 of 249 | 32 of 243 |
| Nausea | Gastrointestinal disorders | 66 of 249 | 45 of 243 |
| Anorexia | Metabolism and nutrition disorders | 70 of 249 | 40 of 243 |
Serious events with the highest arm-level rate: dyspnea (5.8%), cardiac general - other (1.6%), pain chest/thorax nos (1.6%), diarrhea (1.6%), infection - other (1.6%).
The registry reports serious adverse-event figures for participants at risk in each group. For gefitinib, 249 were at risk and 34 were recorded as affected; for placebo, 243 were at risk and 43 were recorded as affected. These are counts as reported, not estimates of a treatment effect. The registry information does not provide a comparative statistical test or confidence interval for these figures.
The listed serious adverse-event terms include dyspnea at 5.8%, cardiac general - other at 1.6%, pain chest/thorax NOS at 1.6%, diarrhea at 1.6%, infection - other at 1.6%, and pneumonitis at 1.6%. The listing does not assign these term-specific percentages to a particular treatment group in the information. They should not be treated as group-specific estimates or as evidence of a between-group difference.
The registry also reports counts for other adverse events: 240 among 249 at risk in the gefitinib group and 226 among 243 at risk in the placebo group. It does not provide details about event severity, recurrence, duration, or the rules used to classify events as serious or other. These counts should be read in that limited context. They do not establish that treatment caused an event, and the serious-event figures alone do not provide a complete assessment of safety.
13. What the Result Does, and Does Not, Mean
The posted overall-survival results describe a randomized comparison of gefitinib and placebo after complete surgical removal of stage IB, II, or IIIA non-small cell lung cancer. At 5 years, the reported survival estimates are 52% for gefitinib and 57% for placebo, each accompanied by a 95% confidence interval. The log-rank analysis reports a hazard ratio of 1.24, a 95% confidence interval from 0.94 to 1.64, and p=0.14.
These data do not provide statistically clear evidence of an overall-survival difference under the reported primary analysis. The confidence interval includes the hazard-ratio reference value of 1, and the p-value is above the 0.05 level described in the planning assumptions. At the same time, the findings do not demonstrate that the treatments are equivalent. The interval includes a range of possible effects on either side of the reference, so the estimate remains uncertain.
The outcome is overall survival, defined by death from any cause, and the primary population is ITT. These results do not answer every question about treatment: the listed secondary outcomes, toxicities, and laboratory biomarker analysis are not fully reported in the information described for this analysis. The record also does not establish whether effects differ by stage or histology; subgroup-specific results are not reported.
General statistical context: a trial result is not a guarantee about an individual outcome, and statistical significance is not the same as clinical importance. The registry result concerns a group comparison under the stated analysis, with uncertainty reflected in the confidence interval. It should not be interpreted as proof of benefit, harm, or no effect. The posted data support a measured conclusion about the evidence from this trial’s reported overall-survival analysis, not a treatment recommendation.
The record is marked completed, but completion status does not supply missing methodological details or unreported outcome findings. The interpretation is therefore limited to the survival estimates, comparative analysis, and adverse-event counts actually reported.
14. Why This Trial Matters Statistically
This trial illustrates why clinical-trial results should be read through both the endpoint estimates and the comparative analysis. The 5-year survival percentages offer a time-point summary, while the log-rank hazard ratio uses event-time information over follow-up. Neither summary alone describes every aspect of the survival experience, and they should not be treated as interchangeable.
It also demonstrates the role of uncertainty. The reported hazard ratio is accompanied by a confidence interval that includes the no-difference reference, and the reported p-value is 0.14. This combination calls for restraint: the analysis does not show a statistically clear difference, but it does not establish equivalence. Readers need the interval, not only the point estimate, to understand the range of effects still compatible with the data and method.
The registry specifies stratified and unadjusted analyses, but does not identify the stratification factors in the information. This highlights how essential analysis details are for interpreting or reproducing a result. A comparison adjusted through a stratified method cannot be fully reconstructed from group-level survival rates alone.
Finally, the record separates a named primary outcome from secondary outcomes and safety reporting, but does not provide complete results or multiplicity details for all listed outcomes. This underscores the importance of distinguishing the principal statistical question from secondary findings and of treating absent information as unknown rather than as evidence of no effect. These considerations apply broadly to interpreting randomized time-to-event trials.
15. 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 registry description leaves several trial and analysis details unavailable. It does not report the randomization sequence method, allocation concealment procedure, or which roles were masked. It also does not identify the stratification factors used in the primary log-rank analysis. These omissions limit assessment of how assignment and adjustment were implemented.
The record does not report the extent or pattern of missing follow-up, the censoring distribution, or sensitivity analyses for missing data. It does not describe checks of assumptions used to interpret the hazard ratio, including whether relative hazards were stable over time. This does not establish that these issues affected the analysis; it means their assessment is not possible from the registry description.
Although disease-free survival and graded toxicities are listed as secondary outcomes, their results are not detailed in the information reported for this analysis. The registry also lists laboratory biomarker analysis without reporting its findings or further methods. It does not provide subgroup results by stage or histology, a multiplicity plan, or an interim-analysis description. Each of these is not reported in the registry record, and none should be inferred from the overall-survival result.
The serious adverse-event listing includes affected counts and several term-specific percentages, but does not give the term percentages by group in the information. Further detail about event definitions, duration, recurrence, and comparative uncertainty is also not reported. Consequently, these figures give only a limited account of safety and cannot establish a comparative treatment effect.
The registry’s sample-size assumptions describe planning illustrations based on the observed effect; they are not a documented justification for the original trial design. The trial’s own sample-size rationale is not reported in the registry record. Overall, the strongest interpretation is confined to the posted primary survival estimates and log-rank analysis, with the limitations above kept in view.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Gefitinib in Treating Patients With Stage IB, II, or IIIA Non-small Cell Lung Cancer That Was Completely Removed by Surgery — NCT00049543.
- Registry record last updated 2015-01-01; status last verified 2014-03.
- Results first posted 2015-01-01.
- 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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19. Record Summary
The registry record describes a completed, randomized, double-blind, parallel-group, placebo-controlled phase III trial sponsored by the National Cancer Institute. It lists enrollment of 503 and compares oral gefitinib with oral placebo after complete surgery for stage IB, II, or IIIA non-small cell lung cancer. Treatment was described as once daily for 2 years unless progression or unacceptable toxicity occurred.
Overall survival was the primary outcome in the ITT population, assessed from randomization to death from any cause and reported as the 5-year survival rate. The posted rates were 52% for gefitinib and 57% for placebo. The log-rank analysis reported a hazard ratio of 1.24, a 95% confidence interval from 0.94 to 1.64, and p=0.14. The interval includes the no-difference reference, so the analysis does not show a statistically clear difference while leaving uncertainty about the effect.
Disease-free survival and graded toxicities were listed as secondary outcomes. Their results, and further analysis details such as missing-data methods and multiplicity handling, are not reported in the registry record.