Anti-angiogenesis Agent AG-013736 in Patients With Advanced Non-Small Cell Lung Cancer: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Anti-angiogenesis Agent AG-013736 in Patients With Advanced Non-Small Cell Lung Cancer (NCT00094094), a na phase 2 study. The primary outcome is Percentage of Participants With Objective Response (OR).

2. Clinical Question

3. Trial Design

This was a Phase 2, single-group study of axitinib in people with advanced non-small cell lung cancer. The registry record gives an enrollment of 32 and identifies Pfizer as the sponsor. The study was conducted at multiple centers in the United States and Germany. Its listed start was 2005-02, primary completion was 2007-07, and status is completed.

Eligible disease was described as cancer that had spread to other parts of the body or locally advanced disease at Stage IIIB with malignant pleural effusion. Participants had to have received at least 1 prior treatment for metastatic disease. Prior adjuvant treatment for localized disease did not count as prior metastatic treatment. The registry record does not give additional eligibility details in the information available for this analysis.

The intervention is named axitinib, while the study description also uses the agent code AG-013736. It is identified as a vascular endothelial growth factor inhibitor. Allocation is recorded as not applicable, the model as single-group, and masking as none. No control treatment or randomized comparison is described.

The primary outcome was the percentage of participants with confirmed objective response. Secondary outcomes listed in the record are progression-free survival, duration of response, and overall survival. The primary-outcome assessment was planned from baseline until first documented progression or discontinuation for any cause, with assessment every 8 weeks up to 98 weeks. These design details define what the study set out to measure, but do not establish what responses or survival outcomes occurred. The primary outcome result and analysis are not reported in the registry record.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Study population included all participants who enrolled and received treatment.

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.

6. Primary Endpoint

The registry lists the primary outcome as Percentage of Participants With Objective Response (OR), measured over Baseline until the date of first documented progression or discontinuation from the study due to any cause, assessed every 8 weeks up to 98 weeks.

The primary endpoint is the percentage of participants with objective response, defined as a confirmed complete response or confirmed partial response according to RECIST. The registry describes the analysis population as all participants who enrolled and received treatment. A complete response requires disappearance of all target and non-target lesions. A partial response requires at least 30 percent decrease in the sum of the longest dimensions of target lesions, using the baseline sum as the reference. A response counts as confirmed only when it persists on repeat imaging at least 4 weeks after it was first documented.

In general, an objective-response endpoint classifies each participant according to whether the specified tumor-response criteria were met, then expresses the result as a percentage of the defined analysis population. Requiring confirmation is intended to distinguish a persistent imaging response from a change that is not sustained at the repeat assessment. This endpoint describes tumor shrinkage under the study’s criteria; it is not by itself a measure of how long participants live or how long disease remains controlled.

The record specifies assessment from baseline until documented progression or discontinuation due to any cause, with imaging assessments every 8 weeks up to 98 weeks. It does not report the number or percentage of confirmed responses, or the associated 95% confidence interval. Without those results, the size and precision of the primary endpoint cannot be evaluated.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a binary percentage endpoint: each participant in the stated analysis population is classified according to whether a confirmed objective response occurred. In general, a percentage for a binary outcome reports the observed frequency of participants meeting a defined criterion relative to the analysis population. The record gives the criterion and population description but does not report the response percentage itself.

What does the confidence interval mean?

The primary outcome names a 95% confidence interval as its measure of uncertainty. In general, a confidence interval expresses the uncertainty around an estimate under the statistical method used. A narrower interval indicates greater precision, while a wider interval indicates less precision. The interval does not guarantee that the true value lies within its particular limits, and it does not resolve design limitations such as the absence of a comparator. Because no estimate or interval limits are reported, the precision of the response estimate cannot be judged from this registry record.

What does confirmation add?

The endpoint requires a complete or partial response under RECIST and repeat imaging at least 4 weeks after the initial response documentation. In general, confirmation makes the endpoint depend on persistence at reassessment rather than a single qualifying scan. The registry also specifies assessments every 8 weeks up to 98 weeks. These rules describe outcome measurement; they do not reveal how many participants met the criteria. The record does not report response counts or the result of the primary analysis.

How should a single-group result be interpreted?

In a single-group study, an outcome percentage describes the observed experience of the treated study population. A randomized comparison instead estimates a contrast between groups assigned different treatments under the trial design. Since this study has no comparator and allocation is listed as not applicable, a treatment contrast cannot be estimated from its design. Even a precisely estimated response percentage would remain a description of the study group rather than a randomized estimate of comparative effect. The registry record does not report an adjusted or unadjusted treatment comparison.

What do the planning assumptions describe?

The record describes a planning illustration based on the observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says that the effect to detect is a stated fraction of the observed effect, and that non-time-to-event planning figures are expressed as participants per arm. These assumptions describe an illustrative future two-arm planning exercise, not the actual single-group study design. The record does not report numerical planning estimates in the information available for this analysis. Such estimates, when present, are planning illustrations and should not be read as observed power or as evidence about the reliability of the trial’s result.

Why can over-dispersion matter?

In general, over-dispersion means that observed variability is greater than a model assumes. When a statistical model does not account for that extra variability, its uncertainty estimates may be too small and its intervals or tests may be poorly calibrated. The registry record does not report a model for the primary percentage endpoint, an over-dispersion assessment, or a detailed statistical analysis plan. No claim about whether over-dispersion was relevant to this study can therefore be made.

What analysis details are available?

The registry states that the primary population included participants who enrolled and received treatment. It also lists progression-free survival, duration of response, and overall survival as secondary outcomes. However, no analysis entries are reported, and the outcome results are not reported in the registry record. The analysis method for the primary endpoint, confidence-interval construction, missing-outcome handling, and any covariate adjustment are not reported in the registry record. These omissions prevent a fuller assessment of how the stated endpoint was estimated.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Axitinib")
n      <- c(32)
events <- c(3)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Axitinib  32  3  9.4  2.0  25.0  3.2  24.2  3.4  24.3

11. Multiplicity, Missing Data and Analysis Populations

The registry lists objective response as the primary outcome and names progression-free survival, duration of response, and overall survival as secondary outcomes. It also records six outcome measures, but the analysis details are not reported in the registry record. No analysis entries are listed. The registry record does not report a multiplicity strategy, such as whether outcomes were tested in a hierarchy or whether statistical error rates were adjusted across outcomes. Without that information, any interpretation of multiple statistical tests would be uncertain; in any event, outcome test results are not reported.

The primary-outcome population is described as all participants who enrolled and received treatment. This defines the stated population but does not explain how missing or unevaluable response assessments were handled. The registry record does not report whether participants without confirmation were counted as nonresponders, excluded, or treated in another way. It also does not report imputation procedures, sensitivity analyses, or the number of missing assessments.

The record does not report the analysis population used for each secondary outcome, censoring rules for time-to-event outcomes, or how discontinuation was handled in those analyses. Although the primary endpoint’s observation period and assessment schedule are described, the analysis methods and results are absent. These gaps limit reproducibility and make it difficult to assess whether the endpoint definitions were applied consistently across participants.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: disease progression nos (15.6%), confusion (9.4%), dehydration (6.2%), dyspnoea nos (6.2%), acute coronary syndrome (3.1%).

The registry reports 16 participants affected by serious adverse events among 32 at risk in the axitinib group. For other adverse events, it reports 31 affected among 32 at risk. These are participant-level figures as recorded for the group; they should not be interpreted as counts of individual event episodes. The registry does not report deaths in the safety fields available for this analysis.

The serious adverse-event terms listed with percentages are disease progression NOS, 15.6%; confusion, 9.4%; dehydration, 6.2%; dyspnoea NOS, 6.2%; acute coronary syndrome, 3.1%; and bradycardia, not otherwise specified (NOS), 3.1%. These entries are the selected terms listed in the record, not a complete description of every possible event. The record does not state in this information whether the listed terms are mutually exclusive, so their percentages should not be added or treated as categories that partition the participants.

In general, an at-risk denominator indicates the group considered for a safety measure, while an affected-participant count indicates how many participants were recorded as having an event of that type. These figures are descriptive. With no comparator group, they do not estimate a relative safety difference against another treatment. Definitions, timing, severity details beyond the serious-event classification, and event-level narratives are not reported in the registry record.

13. What the Result Does, and Does Not, Mean

The study was designed to assess confirmed objective response to axitinib among participants with advanced non-small cell lung cancer after prior treatment for metastatic disease. Its primary endpoint is clearly defined in the registry record, including the RECIST-based criteria, confirmation requirement, assessment schedule, and stated analysis population. The record also reports safety figures for the treated group and names secondary outcomes.

What cannot be established is the primary response result. The registry record does not report the observed percentage of participants with confirmed objective response or its 95% confidence interval. Therefore, the result’s magnitude and precision cannot be described, and the study objective must not be mistaken for a study finding. The missing outcome estimate also means that the registry information does not support a conclusion about how frequently the defined response occurred in this population.

The study’s single-group design also limits what any observed percentage could establish. There is no concurrent comparator, and allocation is listed as not applicable. Descriptive outcomes among treated participants do not provide a randomized estimate of what would have happened under another treatment or no study treatment. The registry does not report comparative efficacy estimates or analyses.

The posted safety counts describe participants recorded as affected, and the listed serious adverse-event terms give percentages. They do not, on their own, establish comparative safety. Results for progression-free survival, duration of response, and overall survival are not reported in the registry record. Taken together, the available information supports an account of the design, endpoint definitions, and reported safety observations, but not a conclusion about the study’s efficacy outcomes or comparative effects.

14. Why This Trial Matters Statistically

This trial illustrates why a clearly described endpoint and a reported endpoint result are different things. The registry defines objective response using confirmed complete or partial response under RECIST, specifies the analysis population, and describes the assessment schedule. Those details help readers understand what the study intended to measure. Yet without the observed percentage and its confidence interval, readers cannot assess the response estimate or its precision from the registry record.

The single-group structure is also important to statistical interpretation. A one-group study can document outcomes among treated participants, but it does not supply a randomized comparison. Even if the primary percentage were reported, it would not by itself estimate a treatment effect relative to a control group. This distinction helps prevent a within-study observation from being read as a comparative claim.

The record also shows why analysis details matter. It names several secondary outcomes, but does not report analysis entries, a multiplicity strategy, or how missing assessments were handled. These omissions make it harder to evaluate the full statistical evidence and its reproducibility. Similarly, a planning illustration based on an observed effect should not be confused with the trial’s actual design or with observed power.

Finally, safety figures require attention to denominators and outcome definitions. Participant counts affected by serious and other adverse events are descriptive, while listed event-term percentages are not necessarily mutually exclusive. Without a comparison group and fuller analysis detail, they cannot establish relative safety. The study is therefore a useful example of interpreting registry records with care: endpoint definitions and design features can be informative even when the clinical outcome results needed for direct statistical evaluation are not reported.

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 most consequential limitation for interpreting efficacy is that the registry record does not report the primary objective-response percentage or its 95% confidence interval. Although the endpoint and its assessment schedule are described, the primary analysis result is unavailable. Secondary outcomes are named, but their results are not reported in the registry record either.

The single-group design provides no randomized comparator. This restricts interpretation to outcomes recorded among participants who received axitinib and does not support a direct estimate of comparative treatment effect. Masking is recorded as none, and the record does not describe procedures that might reduce assessment bias. The registry record does not report whether response assessments were independently reviewed.

The stated primary population includes participants who enrolled and received treatment, but missing-data and unevaluable-assessment rules are not reported in the registry record. This leaves uncertainty about how incomplete follow-up or absent confirmation could affect the endpoint estimate. Analysis methods, including confidence-interval construction and any adjustments, are also not reported. The registry lists multiple outcomes but does not report a multiplicity strategy or analysis entries.

Safety interpretation has its own limits. The record lists affected participants and selected serious adverse-event terms, but does not provide deaths in the available fields or enough information to determine how event terms overlap. No comparator is available for a relative safety assessment. These limitations are specific to the record and design information presented; additional protocol or analysis information is not reported in the registry record.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Anti-angiogenesis Agent AG-013736 in Patients With Advanced Non-Small Cell Lung Cancer — NCT00094094.
• Registry record last updated 2012-06-26; status last verified 2012-06.
• Results first posted 2012-03-16.
• 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.

19. Record Summary

This completed Phase 2 study evaluated axitinib, also called AG-013736, in a single group of participants with advanced non-small cell lung cancer after prior treatment for metastatic disease. The registry lists enrollment of 32, no masking, and no comparator. The primary endpoint was confirmed objective response under RECIST in participants who enrolled and received treatment.

The record describes the response criteria, confirmation requirement, assessment schedule, and secondary outcomes of progression-free survival, duration of response, and overall survival. It reports serious and other adverse-event participant counts and selected serious-event terms. However, the primary response estimate, its confidence interval, secondary-outcome results, and analysis entries are not reported in the registry record. The design and posted safety figures can be described, but efficacy and comparative treatment effects cannot be assessed from the available results.