Real World Utilization and Outcomes With Dacomitinib First Line Treatment for EGFR Mutation-positive Advanced Non Small Cell Lung Cancer Among Asian Patients - A Multi Center Chart Review: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Real World Utilization and Outcomes With Dacomitinib First Line Treatment for EGFR Mutation-positive Advanced Non Small Cell Lung Cancer Among Asian Patients - A Multi Center Chart Review (NCT04609319), a registered phase not stated study. The primary outcome is Body Mass Index (BMI): All Asian Participants.

2. Clinical Question

The study also names outcomes concerning progression-free survival, adverse events, time to treatment failure, starting dose, and oral dose modifications. These are descriptive questions about treatment use and outcomes in the observed population, rather than a randomized test of dacomitinib against another treatment. Because there is no described comparison group, the record cannot establish whether observed outcomes differ from what would have occurred under another treatment or without treatment.

3. Trial Design

NCT04609319 is a completed, multicenter chart review sponsored by Pfizer. Its title describes real-world use and outcomes with first-line dacomitinib among Asian patients with EGFR mutation-positive advanced non-small cell lung cancer. The study is described as a longitudinal, consecutive case series with mixed prospective and retrospective data collection. Its recorded enrollment is 307.

Eligible adults were followed from the date of advanced non-small cell lung cancer diagnosis until death, loss to follow-up, withdrawal of consent, or the end of the study, whichever occurred first. The primary outcome uses a baseline body mass index measurement: the last non-missing measurement before dacomitinib initiation. The registry describes data collection for approximately 89 months and evaluation in this observational study for approximately 35.5 months. These are the registry’s descriptions of the measurement and evaluation periods; further detail about how those periods were set is not reported in the registry record.

The study has one listed cohort, with no cohort description entered. Dacomitinib dose groups are listed for adverse-event reporting, but the registry does not describe random assignment or a treatment comparator. The study start date is 2021-06-11, and the primary completion date is 2024-05-28. The record reports completed status.

A chart review can describe measurements and events among people who received treatment in routine care. Its observational design does not, by itself, separate treatment effects from differences in patient characteristics, clinical decisions, follow-up, or record availability. The registry record does not report a protocol-level statistical analysis plan or a justification for the enrollment target.

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: Data was collected retrospectively from medical records (1-Jan-2017 to 23-Nov-2021) or prospectively from prospective data collection (23-Nov-2021 to 28-May-2024) or mixed (retrospective and prospective, 1-Jan-2017 to 28-May-2024 \[89 months\]). Available data from eligible participants was evaluated in approximately 35.5 months (study start date: 11-June-2021 to study completion date: 28-May-2024) of this observational study as per its objectives.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: FAS included all eligible participants who fulfilled all inclusion and exclusion criteria and provided informed consent (or with IRB/ IEC waiver of informed consent). Here "Overall Number of Participants Analyzed" signifies participants evaluable for this outcome measure.

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

Population: Full Analysis set (FAS) included all eligible participants who fulfilled all inclusion and exclusion criteria and provided informed consent (or with institutional review board \[IRB\]/ independent ethics committee \[IEC\] waiver of informed consent).

6. Primary Endpoint

The registry lists the primary outcome as Body Mass Index (BMI): All Asian Participants, measured over Baseline (date of last non-missing measurement prior to dacomitinib initiation; from data collected for approx. [approximately] 89 months); data was evaluated in this observational study for approx. 35.5 months.

Body mass index is a continuous measure derived from body weight and height. The registry defines it as weight divided by height squared and expresses it in kilograms per square meter. The primary endpoint is the mean body mass index for all Asian participants at baseline, where baseline is defined as the last non-missing measurement before dacomitinib initiation. The registry specifies standard deviation as the measure of dispersion.

As a general statistical concept, a mean describes the central value of a continuous measure in a group, while a standard deviation describes the spread of individual measurements around that mean. Together, they can help characterize the body-size distribution of the participants included in the analysis. They do not describe how participants’ body mass index changed after treatment began, because the primary endpoint is defined using a pre-initiation measurement.

Baseline body mass index can serve as a descriptive characteristic of the study population. It does not directly measure tumor response, progression, survival, or treatment tolerability. Those topics appear among the study’s other outcomes, but the primary endpoint is not an efficacy comparison. The numerical mean, standard deviation, and number of participants analyzed for body mass index are not reported in the registry record, so the observed baseline distribution cannot be characterized from the posted results described in the record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the primary summary describe?

The primary outcome is a mean, a standard way to summarize a continuous measurement across participants. In general, the mean combines the observed values into one measure of the group’s central level. The accompanying standard deviation describes the spread of those measurements. A mean and standard deviation are descriptive statistics; neither alone indicates how precisely the mean has been estimated. Precision depends in part on the number of observations and the variability in the data. The registry specifies the intended summary but does not report the primary outcome’s numerical result or analysis count.

The measurement is body mass index at baseline, defined as the last non-missing value before dacomitinib initiation. This definition selects a pre-treatment measurement rather than a change from baseline. The registry says body mass index was calculated from weight and height, with weight divided by height squared. It does not report details such as the distribution of values, how measurement sources were reconciled, or whether any transformations or adjustments were used.

What can an observational case series establish?

In general, a longitudinal observational study follows information over time without assigning participants to treatment groups at random. A consecutive case series aims to include eligible cases in sequence, but the registry record does not provide enough detail to assess how completely consecutive enrollment was achieved at the participating centers. Mixed prospective and retrospective collection means the record describes both forward-looking and existing-data collection, but further procedures for either source are not reported.

This design can document treatment patterns and outcomes in the observed population. It does not ensure that groups receiving different doses are comparable. In general, dose choice in routine care can be related to patient or clinical characteristics, and those characteristics can also relate to outcomes. Without randomization or an adequately described adjustment strategy, associations between dose and outcomes would not establish that dose caused the observed differences. The registry does not report an adjustment plan or a statistical comparison between dose groups.

How should uncertainty be understood?

In general, a confidence interval gives a range of values compatible with the data under a specified statistical procedure and conveys estimation uncertainty. A standard deviation instead describes variability among individual observations; it is not a confidence interval for the mean. The registry record does not report a confidence interval for the primary outcome. It also does not report a numerical mean or standard deviation, so neither the observed value nor its precision can be evaluated.

For outcomes involving time until an event, such as progression-free survival or time to treatment failure, general statistical methods may account for participants who have not experienced the event by the end of their observed follow-up. Those methods require definitions of the event, censoring, and analysis procedures. Although the registry lists time-to-event outcomes, the definitions and analysis results needed to interpret them are not reported in the registry record. No survival estimate or precision measure is available in the record described.

What do the planning assumptions mean?

The stated planning illustration uses a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It defines the effect to detect as a stated fraction of the observed effect. For time-to-event outcomes, the stated illustration is based on the total number of events; for other outcomes, it is based on participants per arm. These are planning assumptions, not a description of the observed study design. They do not establish that this chart review had two randomized arms or that it was planned around a particular comparison.

In general, a sample-size calculation estimates how much information a hypothetical study might need for a chosen statistical objective under specified assumptions. Its result depends on the assumed effect and other design choices. The record does not report a protocol sample-size justification, and the numerical planning results are not reported in the registry record. Any planning illustration based on an observed effect should not be interpreted as observed power or as evidence that the study was adequately powered. The registry does not provide enough information to assess the assumptions against the study’s actual outcome data.

Why does over-dispersion matter in general?

Over-dispersion means that observed variation is greater than a statistical model expects. In general, failing to account for it can make uncertainty estimates too small, so standard errors and confidence intervals may be misleading. Whether over-dispersion is relevant depends on the outcome and model. The registry record does not report a model for the primary continuous outcome or any over-dispersion assessment, so no such issue can be evaluated for the posted results.

Overall, the record identifies the primary measure, its timing, and the planned descriptive summary. It does not report enough numerical results or modeling details to reproduce or assess an inferential analysis. General statistical descriptions explain what the specified summaries would mean, but do not fill in the missing outcome estimates or undocumented methods.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 18 outcome measures, including a primary body mass index measure and secondary outcomes concerning progression-free survival, adverse events, time to treatment failure, dose, and oral dose modifications. It lists 0 analyses. The registry record does not report a statistical plan for handling multiple outcomes, multiple comparisons, or repeated analyses. It is therefore not possible to determine whether any multiplicity adjustment was planned or applied.

In general, evaluating many outcomes can increase the chance of finding an apparently notable result by chance when each is tested separately. Multiplicity procedures can address that issue, but their appropriateness depends on the questions and analysis plan. The number of listed outcomes alone does not show that statistical tests were performed, and it does not indicate whether a correction was used. No inferential results or adjustment details are reported in the registry record.

The registry defines the full analysis set as eligible participants who met the inclusion and exclusion criteria and provided informed consent, or whose consent was waived by an IRB or IEC. It further states that the number analyzed for a given outcome refers to participants evaluable for that outcome. The number evaluable for baseline body mass index is not reported in the registry record.

For the primary measure, the registry uses the last non-missing body mass index measurement before dacomitinib initiation. This describes which measurement is used when a non-missing value is available; it does not explain how missing measurements were handled across participants or why they were missing. The extent and pattern of missing data, any imputation procedure, and any sensitivity analysis are not reported in the registry record. Those omissions limit assessment of how representative the analyzed participants are of all eligible participants.

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

The primary outcome, as defined, would describe baseline body mass index among participants evaluable for that measure. Because the numerical mean, standard deviation, and analysis count are not reported in the registry record, the observed level and spread cannot be stated. The endpoint also does not measure change during treatment or directly indicate cancer control.

The broader study asks descriptive questions about first-line dacomitinib use and outcomes in Asian patients with EGFR mutation-positive advanced non-small cell lung cancer. Such information can characterize the experience of patients included in a multicenter chart review. It cannot, without a suitable comparison and a defensible analysis, establish what outcomes would have been under a different treatment. The registry record describes no randomized comparator, and it cautions that the dose groups are not like-for-like control groups.

Recorded deaths in the listed dose groups should be interpreted as counts, not as comparative risks or treatment-attributed outcomes. The registry does not report the denominators and follow-up context needed to turn those counts into rates, nor does it report whether the deaths were judged related to treatment. The listed zero values for adverse-event participants at risk and affected do not resolve those uncertainties.

More generally, the absence of numerical results or analysis details in the registry record should not be mistaken for a null finding. It means the posted record does not permit a judgment about the size, direction, or precision of the primary outcome or the other listed outcomes. Nor does the observational design alone support a causal conclusion. The study’s findings, if reported elsewhere, would require assessment in light of measurement completeness, outcome definitions, follow-up, and the methods used to account for differences among participants.

12. Why This Trial Matters Statistically

Real-world observational studies can address questions about how a treatment is used and what outcomes are recorded among patients receiving it in clinical settings. This study focuses on Asian adults with EGFR mutation-positive advanced non-small cell lung cancer treated with dacomitinib as first-line therapy. Its multicenter, longitudinal, consecutive case-series description gives a useful framework for understanding the intended population and data collection.

Statistically, the primary endpoint illustrates the distinction between describing a population and estimating a treatment effect. Baseline body mass index, summarized by a mean and standard deviation, characterizes participants before treatment initiation. It is not itself a comparison of therapies or an outcome of tumor response. The measure’s timing is important to its interpretation.

The record also makes clear why design context matters when considering dose groups. Dose-specific counts without random allocation, group denominators, and sufficient adjustment information cannot establish a comparative effect. Likewise, counts of deaths or adverse events require definitions, follow-up context, and ascertainment details before they can be interpreted as risks or attributed to treatment.

The record’s limits are instructive: an outcome definition is not an outcome result, a listed endpoint is not proof that a statistical analysis was reported, and a planning calculation is not observed power. Here, the registry identifies the primary measure and several secondary questions, but does not report their numerical results or a detailed statistical analysis plan. Keeping those distinctions explicit prevents descriptive registry information from being mistaken for comparative evidence.

13. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The most direct limitation for interpreting the primary outcome is that its numerical mean, standard deviation, and analysis count are not reported in the registry record. Although the endpoint and baseline measurement rule are specified, the posted information does not show the observed body mass index distribution or its precision.

The study is an observational case series without a described randomized comparator. Allocation is not stated, and the registry warns that the arms are not a like-for-like control comparison. This limits causal interpretation, particularly for any apparent differences among dose groups. The registry record does not report an adjustment strategy that could address differences among participants or treatment selection.

Important details for evaluating the recorded outcomes are also absent. The number of participants evaluable for each outcome, missing-data extent and handling, outcome-specific analysis methods, and the statistical plan are not reported in the registry record. For the listed death counts, the record does not provide the denominators, attribution, or context needed for rates or causal interpretation. The adverse-event entries therefore cannot be read as a complete account of safety findings.

The study combines prospective and retrospective data collection, but the registry does not describe how measurements and events were collected or verified across those sources and centers. It also does not provide enough detail to assess the completeness of consecutive enrollment. These limitations concern what can be concluded from the registry record; they do not establish that the study itself lacked procedures or analyses that are not recorded there.

14. Related Tutorials

15. Related Statistical Calculators

16. Sources

• ClinicalTrials.gov: Real World Utilization and Outcomes With Dacomitinib First Line Treatment for EGFR Mutation-positive Advanced Non Small Cell Lung Cancer Among Asian Patients - A Multi Center Chart Review — NCT04609319.
• Registry record last updated 2025-05-31; status last verified 2025-05.
• Results first posted 2025-05-31.
• 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.

17. Record Summary

NCT04609319 is a completed, Pfizer-sponsored multicenter chart review of first-line dacomitinib use among Asian patients with EGFR mutation-positive advanced non-small cell lung cancer. It is described as a longitudinal consecutive case series with mixed prospective and retrospective data collection. Enrollment was 307; the study start date was 2021-06-11, and the primary completion date was 2024-05-28.

The primary outcome is baseline body mass index, defined as the last non-missing measurement before dacomitinib initiation and summarized as a mean with standard deviation. Its numerical result and analysis count are not reported in the registry record. The record lists 18 outcome measures and 0 analyses. It does not describe a randomized comparator or report a detailed statistical analysis plan, missing-data approach, or multiplicity procedure.