Phase 3 Study Evaluating Efficacy, Safety and Pharmacokinetics of Trilaciclib In Small Cell Lung Cancer Patients: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Phase 3 Study Evaluating Efficacy, Safety and Pharmacokinetics of Trilaciclib In Small Cell Lung Cancer Patients (NCT04902885), a randomized phase 3 study. The primary outcome is Area Under the Plasma Concentration Versus Time Curve From Time Zero Extrapolated to Infinity(AUC0-inf) for Part 1.

2. Clinical Question

3. Trial Design

NCT04902885 is a completed, randomized, quadruple-masked, parallel Phase 3 study sponsored by Jiangsu Simcere Pharmaceutical Co., Ltd. Its official title describes a multicenter study of trilaciclib in patients with extensive-stage small-cell lung cancer. The registry lists the start date as 2021-05-25 and the primary completion date as 2021-12-29. Enrollment is listed as 95.

The brief summary divides the study into two parts. Part 1 was a safety run-in and pharmacokinetic evaluation. Its description specifies 12 patients, with 6 in first-line treatment and 6 in second- or third-line treatment. The Part 1 arm description identifies a trilaciclib group receiving trilaciclib plus chemotherapy.

Part 2 is described as a randomized, double-blind, placebo-controlled efficacy confirmation study, stratified by first-line versus second- or third-line treatment, ECOG PS [0-1 vs 2], and brain metastases. The arm descriptions list 41 patients in the Part 2 trilaciclib group and 42 in the Part 2 placebo group. Both groups received chemotherapy: carboplatin with etoposide or topotecan. The listed trilaciclib dose is 240mg/m^2.

The study is described as including screening, treatment, safety follow-up, and survival follow-up. The registry record does not report the duration of these periods. It also does not report the allocation ratio, the detailed randomization procedure, or how masking was maintained. The brief summary describes the Part 2 stratification factors, but does not give the precise procedures used to implement stratification.

The record lists 18 outcome measures and one analysis. The available primary endpoint description is for pharmacokinetic exposure in Part 1. Although the study summary characterizes Part 2 as an efficacy confirmation study, the posted primary outcome information does not specify one clinical efficacy endpoint suitable for a single treatment-effect interpretation.

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: For Part 1, of 14 enrolled participants, 12 met inclusion criteria and were treated with trilaicilib plus chemotherapy. For Part 2, of 105 enrolled participants, 83 met inclusion criteria and were randomized to treatment.

Overall Study

Analysis population for the primary outcome, as defined in the registry: PK Analysis Set (PKS): All patients who received at least one dose of the study drug and had at least one valid concentration data of the tested components after drug administration. Pharmacokinetic analyses will be based on the PKS set.

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 Area Under the Plasma Concentration Versus Time Curve From Time Zero Extrapolated to Infinity(AUC0-inf) for Part 1, measured over Day1 and Day 3( or Day 5) of Cycle 1 for a 21-day cycle.

The primary endpoint is the area under the plasma concentration-versus-time curve from time zero extrapolated to infinity, abbreviated AUC0-inf, for Part 1. It is expressed in h*ng/mL. The registry describes it as the area under the plasma concentration-versus-time curve for trilaciclib, assessed on Day1 and Day 3( or Day 5) of Cycle 1 for a 21-day cycle.

This pharmacokinetic measure represents drug exposure over time, including an extrapolated portion after the last measured concentration. General explanation: the area under a concentration-time curve combines information about measured concentrations and their timing. It is used in pharmacokinetic assessment because a single concentration at one time point cannot describe exposure across the dosing interval or the subsequent decline in concentration.

The registry says AUC0-inf was determined from individual concentration-time data using non-compartmental analysis and actual sampling times in relation to dosing. It identifies the geometric mean as the summary parameter and the geometric coefficient of variation as its dispersion measure. The specified population is the Pharmacokinetic Analysis Set: patients who received at least one dose of study drug and had at least one valid post-administration concentration measurement for a tested component.

The endpoint is pharmacokinetic, rather than a direct measure of tumor response, survival, or hematologic toxicity. Its result could describe trilaciclib exposure in the Part 1 analysis population, but the numerical estimate and dispersion are not reported in the registry record. The registry record therefore does not support a quantitative interpretation of exposure or a comparison between treatment groups for this endpoint.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the primary endpoint summarize?

The primary endpoint is AUC0-inf, a pharmacokinetic measure of trilaciclib exposure. The registry states that it was calculated from individual concentration-time data using non-compartmental analysis, with actual sampling times in relation to dosing. The intended assessment points are Day1 and Day 3( or Day 5) of Cycle 1 for a 21-day cycle. AUC0-inf is summarized as a geometric mean, with geometric coefficient of variation describing dispersion.

General explanation: non-compartmental analysis estimates pharmacokinetic quantities from observed concentration-time data without requiring a fully specified compartment model. The use of actual sampling times matters because samples may not be taken at perfectly identical intervals for every participant. The record names this approach but does not report the calculation details, software, or rules for handling particular data patterns.

What do geometric summaries mean?

General explanation: a geometric mean is often used for positive measurements that are distributed asymmetrically, because it summarizes values on a multiplicative scale. The geometric coefficient of variation describes relative spread on that scale. These summaries are not interchangeable with an arithmetic mean and standard deviation. The registry identifies the chosen summaries but provides no numerical estimate or dispersion value, so no magnitude or precision can be described.

The PK Analysis Set is defined as patients who received at least one dose of study drug and had at least one valid concentration measurement after administration for a tested component. This definition makes inclusion dependent on both treatment exposure and an evaluable concentration observation. The number of patients in that set, the number with complete sampling, and the handling of missing or invalid samples are not reported in the registry record.

How should the randomized comparison be understood?

Part 2 is described as randomized, double-blind, placebo-controlled, and parallel. The intervention comparison is trilaciclib plus chemotherapy versus placebo plus chemotherapy. General explanation: random allocation is intended to make treatment groups comparable on average, including with respect to factors that are not measured, while masking can reduce the influence of treatment knowledge on care and assessment. These design features do not guarantee that all sources of bias are eliminated, and they do not substitute for outcome results.

The summary says randomization was stratified by treatment line, ECOG PS [0-1 vs 2], and brain metastases. Stratification is generally used to help balance specified characteristics between treatment groups. The registry record does not report the randomization sequence method, the allocation concealment process, the stratification implementation, or whether any analysis adjusted for those factors.

What can be inferred from adverse event counts?

The posted safety information gives the number at risk and the number affected for serious adverse events and other adverse events in each listed group. General explanation: a count describes how many participants had an event under the registry’s reporting definition; it does not capture event duration, severity beyond the stated category, timing, or the number of recurrent events. Comparisons based only on counts can also be difficult to interpret when follow-up time or exposure differs. Those details are not reported in the registry record.

The listed deaths are counts, not a cause-specific survival analysis. No time-to-event estimate, censoring information, or cause of death is reported in the registry record. The serious adverse event terms and percentages are presented without enough context in the record to reconstruct their analysis denominator or determine whether terms overlap within participants. They should not be treated as mutually exclusive categories or as comparative treatment effects.

Why are no efficacy calculations described?

The record lists 18 outcome measures and one analysis, but the primary result presented for interpretation is not reduced to a single clinical efficacy comparison. The skip note indicates that the primary outcome has several categories or time points and is not reduced to one comparison. Thus, no single effect estimate or recalculation is available to interpret from the posted information.

General explanation: an effect estimate describes the direction and size of a contrast, while a confidence interval describes the range of values compatible with the data under the analysis assumptions. A p-value addresses the compatibility of the data with a specified null hypothesis; it does not convey effect size or clinical importance by itself. None of these quantities for an efficacy comparison is reported in the registry record. No recalculated results or planning illustrations can replace missing observed results.

The registry record also does not report the statistical model, covariate adjustment, hypothesis-testing procedure, handling of repeated measurements, or criteria for analysis populations beyond the PK set definition. Statistical methods should therefore not be inferred from the study’s Phase 3 designation or its randomized design. Interpretation is limited to what the record explicitly describes.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 18 outcome measures, including the Part 1 pharmacokinetic endpoint and a range of hematologic and supportive-care outcomes. When a study evaluates multiple endpoints, time points, or outcome categories, the chance of obtaining at least one apparently unusual result can increase if each is tested independently. General explanation: multiplicity procedures can manage that issue by controlling a prespecified error rate or by organizing testing in a defined sequence. The registry record does not report a multiplicity adjustment, testing hierarchy, or other strategy for interpreting multiple outcomes.

The record’s skip note says the primary outcome has several categories or time points and is not reduced to one comparison. This means a single treatment-effect summary cannot be stated from the posted result description. The statistical analysis plan, prespecified primary comparison, and any interim analyses are not reported in the registry record. Their presence or absence should not be inferred.

Missing-data methods are also not reported in the registry record. The PK Analysis Set definition requires at least one valid post-dose concentration measurement, but the record does not give the number of participants with missing samples, the reasons for missingness, or the methods used to handle incomplete concentration profiles. For the clinical outcomes, the record does not specify whether analyses used all randomized participants, participants who received treatment, or another population.

These details matter because exclusions and missing observations can affect the meaning of an estimate. General explanation: an analysis population defines which participants contribute to a particular result, while a missing-data approach sets out how incomplete observations are treated. Neither should be assumed from the brief design description. The record’s stated PK population is the only explicit analysis-population definition in the available information.

11. Safety Results

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

Deaths

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: platelet count decreased (14.3%), neutrophil count decreased (11.9%), oxygen saturation decreased (8.3%), acute cardiac failure (8.3%), febrile neutropenia (7.1%).

The registry lists serious adverse event information for three groups: Part I ( Safety run-in and PK Evaluation); Trilaciclib Group, Part II ( Randomized Double-blind, Placebo-controlled ), Trilaciclib Group, and Part II ( Randomized Double-blind, Placebo-controlled ), Placebo Group. The respective numbers at risk are 12, 41, and 42; the respective numbers affected by serious adverse events are 4, 12, and 15. These are group-level counts, not estimates of a causal treatment effect.

The numbers listed as affected by other adverse events are 12, 41, and 42, respectively. Death counts are 6, 22, and 28, respectively. The record does not specify causes of death, timing, attribution, or the follow-up period associated with these counts. It also does not provide person-time or a time-to-event analysis. These counts therefore should not be read as evidence that a treatment caused an event or altered mortality.

The most frequent serious adverse event terms listed are platelet count decreased (14.3%), neutrophil count decreased (11.9%), oxygen saturation decreased (8.3%), acute cardiac failure (8.3%), febrile neutropenia (7.1%), and anaemia (4.9%). The record does not report enough denominator or grouping detail to interpret these percentages as arm-specific comparative rates. Event terms may also occur in the same participant. The counts and terms describe posted safety reporting, not a complete assessment of comparative safety.

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

The study record describes a randomized, placebo-controlled Phase 3 design in extensive-stage small-cell lung cancer, with chemotherapy in both Part 2 groups. It identifies a pharmacokinetic primary endpoint in Part 1 and describes Part 2 as an efficacy confirmation study. These design features clarify what the study set out to examine, but they do not supply evidence of an efficacy effect.

The posted primary endpoint is exposure to trilaciclib, measured as AUC0-inf. The registry gives the endpoint definition and analysis population, but no numerical result. Consequently, the posted information does not show the observed exposure level, its dispersion, or a treatment contrast. It cannot establish how precisely exposure was estimated.

The record also lists secondary hematologic and supportive-care outcomes and provides some adverse event counts. Without comparative endpoint results, confidence intervals, or p-values, it is not possible to quantify the difference between the randomized groups for those outcomes. The registry record does not report a single clinical efficacy comparison that can be interpreted as the study’s primary treatment-effect result.

This absence of a numerical result is not evidence that the treatment has no effect. It is a limit on what can be concluded from the registry record. Similarly, the presence of serious adverse event counts does not establish that an event was caused by treatment, and the death counts do not describe cause-specific mortality or survival over time.

General explanation: a trial’s design describes how evidence was intended to be collected, while results are needed to estimate what happened and how uncertain that estimate is. Statistical significance, if reported, would not by itself establish clinical importance; effect size, uncertainty, outcome definition, and study conduct would also matter. Those elements are not available for a clinical efficacy comparison in this record.

13. Why This Trial Matters Statistically

This trial illustrates why the endpoint named in a registry record must be distinguished from the broader purpose described in a study summary. The summary calls Part 2 an efficacy confirmation study, while the listed primary outcome is pharmacokinetic exposure in Part 1. These questions concern different kinds of evidence: exposure describes drug concentration over time, whereas efficacy outcomes assess clinical effects.

The study design also highlights the importance of keeping trial parts separate. Part 1 is described as a safety run-in and pharmacokinetic evaluation, while Part 2 is described as a randomized, double-blind, placebo-controlled comparison. The Part 1 group and Part 2 treatment groups do not answer identical questions and should not be combined as though they formed one randomized comparison.

The record’s safety counts demonstrate another statistical distinction: an event count is not the same as a treatment-effect estimate. Comparative interpretation requires attention to group definitions, follow-up, outcome ascertainment, and uncertainty. The posted record gives some counts but not the follow-up and analysis details needed for a full comparison.

Finally, a completed trial record can contain design and safety information without reporting an interpretable numerical result for its principal clinical question. Statistical reading therefore requires attention not only to the study’s phase and randomization, but also to whether the result, analysis population, uncertainty, and multiplicity approach are reported. In this case, several of those elements are not reported in the registry record, limiting what can be inferred.

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.

The most important limitation is that numerical results for the listed primary pharmacokinetic endpoint are not reported in the registry record. The geometric mean and geometric coefficient of variation are named as summaries, but their values are absent. The available information therefore does not permit interpretation of the observed exposure or its precision.

Although Part 2 is described as an efficacy confirmation study, a single clinical efficacy endpoint and comparative result are not reported in a form that supports a treatment-effect interpretation. The registry record does not give a clinical effect estimate, confidence interval, or p-value for the outcomes described. It also does not report an analysis model, covariate adjustment, or multiplicity strategy.

The record identifies the PK Analysis Set, but does not report its size or the handling of incomplete concentration data. For the clinical outcomes, the analysis populations and missing-data methods are not reported in the registry record. The duration and completeness of follow-up are also not reported, which constrains interpretation of adverse events and deaths.

The serious adverse event counts and listed terms are descriptive. The record does not report event timing, attribution, causes of death, or enough denominator information to make the listed serious-event percentages a clear arm-specific comparison. It also does not state whether recurrent events or overlapping terms were handled in a particular way.

Finally, the summary describes stratification factors but not the randomization procedure or analytic use of those factors. The record does not report a sample-size justification, interim analyses, or a detailed statistical analysis plan. Those omissions limit assessment of the design’s assumptions and the relationship between planned and reported analyses.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Phase 3 Study Evaluating Efficacy, Safety and Pharmacokinetics of Trilaciclib In Small Cell Lung Cancer Patients — NCT04902885.
• Registry record last updated 2024-07-10; status last verified 2024-04.
• Results first posted 2024-07-10.
• 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.

18. Record Summary

NCT04902885 is a completed, randomized, quadruple-masked, parallel Phase 3 study sponsored by Jiangsu Simcere Pharmaceutical Co., Ltd. It enrolled 95 participants with extensive-stage small-cell lung cancer. The study summary describes a Part 1 safety run-in and pharmacokinetic evaluation and a Part 2 randomized, placebo-controlled efficacy confirmation study.

Part 2 compared trilaciclib plus chemotherapy with placebo plus chemotherapy. The primary endpoint listed in the registry is AUC0-inf for trilaciclib in Part 1, summarized as a geometric mean with geometric coefficient of variation. The registry defines the PK Analysis Set but does not report the numerical endpoint result.

Serious adverse event counts, other adverse event counts, deaths, and selected serious-event terms are listed. The registry record does not report a clinical efficacy comparison, its uncertainty, or several analysis details needed for a fuller assessment. The posted information supports description of the design and some safety reporting, but not a quantitative conclusion about efficacy or comparative safety.