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 Trilaciclib, a CDK 4/6 Inhibitor, in Patients Receiving Docetaxel for Metastatic Non-Small Cell Lung Cancer (NSCLC) (PRESERVE 4) (NCT04863248), a randomized phase 2 study. The primary outcome is Incidence of Treatment-Emergent Adverse Events as Assessed by CTCAE v5.0.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04863248 |
| Phase | Phase 2 |
| Condition | Metastatic Non-Small Cell Lung Cancer, NSCLC, Lung Cancer |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 10 |
| Arms in the primary outcome | n/a |
| Lead sponsor | G1 Therapeutics, Inc. |
| Results posted | Yes |
2. Clinical Question
Population
Patients with metastatic non-small cell lung cancer receiving docetaxel in the second- or third-line setting. At termination, 10 patients had been screened and 7 had been randomized; 2 of those randomized had discontinued from the study.
Intervention
Trilaciclib administered intravenously before docetaxel, on Day 1 of each 21-day cycle.
Comparator
Placebo administered intravenously before docetaxel, on Day 1 of each 21-day cycle.
Primary question
The registry’s primary outcome asks about the incidence of treatment-emergent adverse events assessed by CTCAE v5.0, including their occurrence and severity, treatment discontinuations due to adverse events, and trilaciclib adverse events of special interest. The registry’s brief summary also describes the trial as evaluating the effect of trilaciclib on overall survival. However, the primary outcome measure recorded is safety-focused, and the registry states that no statistical analyses of efficacy or safety data were conducted.
The central comparison is between the two assigned treatment strategies, with docetaxel included in both arms. The design therefore concerns the added use of trilaciclib before docetaxel compared with placebo before docetaxel, rather than a comparison of docetaxel with no docetaxel. Because the study ended after a small number of patients had been screened and randomized, the posted record offers limited information for assessing either safety patterns or the broader overall-survival question.
3. Trial Design
PRESERVE 4, registered as NCT04863248, was a Phase 2 randomized, double-blind, parallel-group trial. Its official title describes trilaciclib versus placebo in patients with metastatic NSCLC treated with docetaxel in the second- or third-line setting. The registry describes the study as global and multicenter. Both arms included docetaxel; the assigned difference was trilaciclib or placebo before docetaxel.
In the trilaciclib arm, the listed regimen was intravenous trilaciclib before intravenous docetaxel on Day 1 of each 21-day cycle. In the comparator arm, placebo was administered intravenously before intravenous docetaxel on the same schedule. The masking designation is double, and allocation is recorded as randomized. The registry does not report further details about how randomization was generated, how treatment allocation was concealed, or which parties were masked.
The record lists an enrollment of 10 and a terminated status. It states that the sponsor terminated the study for non-safety reasons. At termination, 10 patients had been screened, 7 had been randomized, and 2 of the randomized patients had discontinued from the study. These figures describe distinct stages of study participation; the screening count is not the same as the randomized count.
The registry’s brief summary says the trial evaluated trilaciclib’s effect on overall survival. The listed primary outcome measure, however, is incidence of treatment-emergent adverse events assessed by CTCAE v5.0. The record says no statistical analyses of efficacy or safety data would be conducted. Details of the planned analysis population, treatment duration, follow-up for overall survival, or a statistical analysis plan 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.
Before assignment: Of the 10 patients enrolled, 3 were screen failures and 7 patients were randomized to treatment.
Overall Study
| Stage | Trilaciclib + Docetaxel | Placebo + Docetaxel |
|---|---|---|
| STARTED | 4 | 3 |
| COMPLETED | 0 | 0 |
| NOT COMPLETED | 4 | 3 |
Reasons for not completing this period:
| Reason | Trilaciclib + Docetaxel | Placebo + Docetaxel |
|---|---|---|
| Sponsor Terminated | 4 | 1 |
| Death | 0 | 1 |
| Withdrawal by Subject | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: This study was terminated by the Sponsor for non-safety reasons. At the time of study termination, 10 patients had been screened, 7 were randomized, and 2 of the 7 had discontinued from the study. In addition, it was decided that there would be no statistical analyses of the efficacy or safety data due to the limited number of patients treated (N=7).
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 | Trilaciclib + Docetaxel | Placebo + Docetaxel | Total |
|---|---|---|---|---|
| Participants analysed | 4 | 3 | 7 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 3 | 2 | 5 |
| Age, Categorical: >=65 years | Participants | 1 | 1 | 2 |
| Age, Continuous | years | 58.3 (SD 11.47) | 62.7 (SD 2.52) | 60.1 (SD 8.57) |
| Sex: Female, Male: Female | Participants | 2 | 1 | 3 |
| Sex: Female, Male: Male | Participants | 2 | 2 | 4 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 | 1 | 2 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 3 | 2 | 5 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 2 | 1 | 3 |
| Race (NIH/OMB): White | Participants | 2 | 2 | 4 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| ECOG Score: 0 | Participants | 1 | 1 | 2 |
| ECOG Score: 1 | Participants | 2 | 2 | 4 |
| ECOG Score: 2 | Participants | 1 | 0 | 1 |
| Stage at Diagnosis: IV | Participants | 4 | 3 | 7 |
| Stage at Diagnosis: Unknown | Participants | 0 | 0 | 0 |
| Histopathologic Type: Adenocarcinoma | Participants | 3 | 2 | 5 |
| Histopathologic Type: Squamous Cell Carcinoma | Participants | 1 | 1 | 2 |
6. Primary Endpoint
The registry lists the primary outcome as Incidence of Treatment-Emergent Adverse Events as Assessed by CTCAE v5.0, measured over Time from date of first dose of trilaciclib/placebo and docetaxel through 30 days following the last dose of trilaciclib/placebo and docetaxel, assessed up to 9 months and 2 days..
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary outcome is the incidence of treatment-emergent adverse events assessed using National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0, or CTCAE v5.0. Its description covers the occurrence and severity of adverse events, study-treatment discontinuation due to adverse events, and trilaciclib adverse events of special interest. The listed unit is participants, and the measure is a number of participants.
The outcome timeframe begins on the date of the first dose of trilaciclib or placebo and docetaxel, and extends through 30 days following the last dose of those treatments. The registry describes assessment as continuing up to 9 months and 2 days. This timeframe is important to interpretation because an event counted under the endpoint is tied to treatment and the specified follow-up window, rather than to an unspecified period of a participant’s life.
In general, adverse-event endpoints are used to describe the types, frequency, and severity of undesirable events observed during treatment and follow-up. A severity grading system provides a common framework for classifying events, but the resulting counts do not by themselves establish that a treatment caused an event. Interpretation also depends on how events were collected, how participants were followed, and whether groups were analyzed consistently. Details of those procedures beyond the registry description are not reported in the registry record.
The primary outcome has multiple components and is not reduced to a single comparison in the posted record. No statistical analyses of safety data are reported, so the endpoint description should not be mistaken for an estimated treatment effect.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The record documents a randomized comparison of trilaciclib plus docetaxel with placebo plus docetaxel, but it does not report a statistical analysis of the efficacy or safety data. The primary outcome is an adverse-event measure, and the registry explicitly says that no statistical analyses of efficacy or safety data would be conducted. Consequently, the posted information does not establish a comparative effect estimate for the primary outcome or for overall survival.
The available safety figures are counts for serious adverse events and deaths in each arm. The registry lists 1 participant affected by a serious adverse event among 4 at risk in the trilaciclib plus docetaxel arm, and 3 among 3 at risk in the placebo plus docetaxel arm. It lists deaths as 0 and 1, respectively. These are descriptive counts in a very small study, not results of a reported inferential comparison. The registry does not provide confidence intervals or a statistical test for these counts.
The named serious adverse-event terms include Staphylococcal sepsis, Acute kidney injury, Urosepsis, Renal failure, and Pneumonia, with percentages listed in the record. Those term-level percentages should not be read as treatment-effect estimates. The record does not establish whether different terms occurred in the same patient, nor does it provide a full event-level account in the information. The term percentages therefore cannot be combined or used to infer the number of affected participants.
In general, small groups produce imprecise estimates: a change in the experience of one participant can substantially alter a descriptive count. This is a statistical limitation, not evidence for or against a treatment effect. Randomization helps define a comparative design, but it does not eliminate uncertainty when little information is available. With no reported analysis, there is no basis in the registry record for judging the magnitude or precision of a treatment difference.
The registry’s brief summary refers to overall survival as an intended subject of evaluation, but no efficacy analysis is reported. The safety endpoint and the survival objective are not interchangeable. The posted counts should therefore be interpreted narrowly as recorded safety information, without extrapolating them to survival, to other outcomes, or to patients beyond those enrolled in this trial.
9. Statistical Methods Explained
Statistical methods help distinguish a descriptive observation from an estimate of a treatment effect. In general, a treatment-effect analysis compares outcomes between the randomized groups using a prespecified outcome definition and a stated analysis approach. The registry record identifies the trial as randomized and double-blind, but states that no statistical analyses of efficacy or safety data were conducted. It does not report a statistical analysis plan, a test, a model, or an adjusted treatment-effect estimate. Accordingly, the arm counts can be described, but they cannot be presented as the output of an inferential comparison.
What does randomization contribute?
In general, randomization assigns participants to treatment groups using a chance-based process. When implemented as intended, it can reduce systematic differences between groups at entry and supports a fair comparison. It does not guarantee that every characteristic will be balanced in a small study, and it cannot compensate for limited outcome information or missing analyses. The registry does not report the randomization sequence method, allocation concealment details, or any baseline characteristics that would allow assessment of group comparability.
The double-blind designation indicates that the record classifies the trial as double-masked. In general, masking can reduce the influence of treatment knowledge on participant reports, clinical care, or outcome assessment. The record does not specify which parties were masked or how masking was maintained. No conclusions about the success of masking can be drawn from the designation alone.
What does an adverse-event count mean?
The primary endpoint is expressed as a number of participants and concerns treatment-emergent adverse events assessed by CTCAE v5.0. A participant count is a way to summarize how many people experienced an event under the endpoint definition. It is different from an event count: one participant can potentially experience more than one event, and the registry does not provide a complete event-level breakdown for the primary outcome. The serious adverse-event figures are reported separately by arm and should be understood as descriptive safety counts.
In general, a comparative analysis of participant counts might report a difference between groups or another effect measure, together with an uncertainty interval and a stated statistical method. A confidence interval, in general, describes a range of values compatible with the data under the assumptions of the chosen method. It communicates precision; it is not a guarantee that the true effect lies in that range. No such comparative estimate or confidence interval is reported for this trial’s safety or efficacy data. A p-value would likewise require a specified test and analysis, and the registry reports no such analysis.
Why does the small amount of information matter?
In general, estimates based on sparse outcomes can be unstable, and conventional approximations may be less dependable when counts are very small. A difference in one participant’s outcome can materially change the pattern of observed counts. This makes it especially important to avoid turning descriptive arm figures into claims of statistical significance or into claims that there is no difference. The record does not report a statistical test, and the counts alone do not answer those questions.
Over-dispersion is a general issue in count data: it occurs when variability exceeds what a chosen probability model expects. When present, an analysis that ignores it can understate uncertainty. The posted record does not report a count model or any assessment of over-dispersion, and the participant-based safety figures do not justify asserting that such a model was used.
What can be inferred from the registry’s analysis statement?
The registry states that there would be no statistical analyses of efficacy or safety data. This is not the same as a reported analysis with a non-significant result. A non-significant result would require an analysis and would still need interpretation in light of its uncertainty. Here, no test result, estimate, confidence interval, or analysis population is reported for those outcomes. The appropriate reading is that inferential results are unavailable in the registry record, not that a treatment effect was found to be absent.
The registry does not report a sample-size justification, target power, interim-analysis plan, handling of repeated measures, covariate adjustment, missing-data method, or strategy for controlling multiple comparisons. In general, these methods can affect how a trial’s estimates and uncertainty are interpreted. Without their documentation, no assumptions about the intended statistical procedures should be made. The distinction between a trial’s design labels and its analysis methods is important: randomization and masking describe aspects of design, but they do not specify how outcomes were analyzed.
10. Multiplicity, Missing Data and Analysis Populations
Multiplicity arises in general when a study evaluates several outcomes, time points, subgroups, or statistical comparisons. If multiple tests are conducted, the chance of at least one apparently unusual result can increase unless the analysis plan addresses that issue. The registry record does not report a multiplicity strategy, testing hierarchy, or statistical analysis plan. It also states that no statistical analyses of efficacy or safety data were conducted, so there are no reported inferential results for which a multiplicity adjustment can be assessed.
The primary outcome description includes occurrence and severity of adverse events, discontinuation due to adverse events, and trilaciclib adverse events of special interest. These are related but not identical safety dimensions. The record does not report how they would be combined, prioritized, or analyzed. It would be inappropriate to assume a particular hierarchy or correction method.
Missing-data methods and analysis populations are also not reported in the registry record. The registry reports that 2 of the 7 randomized patients had discontinued from the study, but does not describe the timing or reasons for those discontinuations in the available information, how their outcomes were handled, or which population would have been used for each analysis. The screening, randomization, and discontinuation counts describe study flow, not the statistical handling of incomplete data.
In general, missing outcomes can affect estimates when the likelihood of missingness is related to prognosis, treatment, or the outcome itself. Appropriate analysis depends on the outcome, the pattern and reason for missingness, and assumptions that should be stated. No such assumptions or methods are reported. The absent information limits interpretation; it does not establish that missingness biased results in a particular direction.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Trilaciclib + Docetaxel | 1 | 4 | 25.0% |
| Placebo + Docetaxel | 3 | 3 | 100.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Trilaciclib + Docetaxel | 0 of 4 |
| Placebo + Docetaxel | 1 of 3 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Trilaciclib + Docetaxel | 4 of 4 |
| Placebo + Docetaxel | 3 of 3 |
Most frequent serious adverse event terms
| Event term | Organ system | Trilaciclib + Docetaxel | Placebo + Docetaxel |
|---|---|---|---|
| Staphylococcal sepsis | Infections and infestations | 0 of 4 | 1 of 3 |
| Acute kidney injury | Renal and urinary disorders | 0 of 4 | 1 of 3 |
| Urosepsis | Infections and infestations | 0 of 4 | 1 of 3 |
| Renal failure | Renal and urinary disorders | 0 of 4 | 1 of 3 |
| Pneumonia | Infections and infestations | 1 of 4 | 0 of 3 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Trilaciclib + Docetaxel | Placebo + Docetaxel |
|---|---|---|---|
| Neutropenia | Blood and lymphatic system disorders | 2 of 4 | 3 of 3 |
| Leukopenia | Blood and lymphatic system disorders | 1 of 4 | 3 of 3 |
| Monocytosis | Blood and lymphatic system disorders | 2 of 4 | 2 of 3 |
| Monocytopenia | Blood and lymphatic system disorders | 3 of 4 | 1 of 3 |
| Eosinopenia | Blood and lymphatic system disorders | 1 of 4 | 2 of 3 |
| Hypoalbuminemia | Metabolism and nutrition disorders | 1 of 4 | 2 of 3 |
| Nausea | Gastrointestinal disorders | 2 of 4 | 1 of 3 |
| Diarrhea | Gastrointestinal disorders | 2 of 4 | 1 of 3 |
| Lymphopenia | Blood and lymphatic system disorders | 0 of 4 | 2 of 3 |
| Metamyelocyte count increased | Investigations | 0 of 4 | 2 of 3 |
Serious events with the highest arm-level rate: staphylococcal sepsis (33.3%), acute kidney injury (33.3%), urosepsis (33.3%), renal failure (33.3%), pneumonia (25.0%).
The registry lists serious adverse-event figures by arm. For trilaciclib plus docetaxel, 1 participant was recorded as affected among 4 at risk; for placebo plus docetaxel, 3 were recorded as affected among 3 at risk. The death counts are listed as 0 and 1, respectively. These are small descriptive counts, and the registry reports no statistical analysis of safety data.
The record also lists Staphylococcal sepsis, Acute kidney injury, Urosepsis, Renal failure, and Pneumonia among the top serious terms, with the respective percentages recorded as 33.3%, 33.3%, 33.3%, 33.3%, and 25.0%. These term-specific percentages are not a comparative analysis between treatment arms. The record does not clarify whether terms could occur in the same participant, so the percentages should not be added or treated as mutually exclusive categories.
In general, an adverse event occurring during a trial is not automatically evidence that the assigned treatment caused it. Attribution requires clinical and methodological assessment, and the posted figures do not report a causal analysis. The small counts, absence of inferential analyses, and limited detail on event-level patterns call for a narrow descriptive reading. They do not support a conclusion about relative safety.
12. What the Result Does, and Does Not, Mean
The registry record establishes that PRESERVE 4 was a randomized, double-blind Phase 2 study comparing trilaciclib before docetaxel with placebo before docetaxel in metastatic NSCLC treated in the second- or third-line setting. It records a safety-focused primary outcome and provides limited serious adverse-event and death counts. It also records that the sponsor terminated the study for non-safety reasons.
What the record does not establish is a statistically analyzed difference between treatment groups. The registry specifically states that no statistical analyses of efficacy or safety data would be conducted. There is no reported treatment-effect estimate, confidence interval, or test result for the primary safety outcome or overall survival. The absence of an analysis is not a finding of no effect, and the small descriptive counts cannot substitute for an analysis.
The brief summary identifies overall survival as an aim of evaluation, while the listed primary outcome concerns treatment-emergent adverse events. The record does not provide an analyzed survival result. It is therefore not possible to use the posted safety information to draw conclusions about survival, nor to infer the overall benefit-risk balance from these counts alone.
In general, the purpose of a randomized trial is to compare assigned strategies under a defined design, but the strength of the conclusions depends on how much outcome information is available and how it is analyzed. Here, enrollment and follow-up stopped before the registry’s record reports any efficacy or safety statistical analysis. The observed data are a limited account of events among participants who entered the study, not a conclusive estimate for the wider population of people with metastatic NSCLC.
The most defensible interpretation is descriptive: the record documents the trial design, its early termination, and the posted safety figures. It does not support statements that trilaciclib improves or worsens outcomes, or that the treatments have equivalent effects.
13. Why This Trial Matters Statistically
This trial illustrates why a study’s design and its reported analyses need to be read separately. Randomization and double masking describe how the comparison was structured. They do not, by themselves, provide an estimate of treatment effect. The registry’s explicit statement that no statistical analyses of efficacy or safety data were conducted is therefore central to interpreting the posted results.
The study also demonstrates how early termination can constrain what a randomized trial can answer. The record reports 10 patients screened, 7 randomized, and 2 of those randomized discontinuing from the study. These figures show that the trial did not proceed to a larger body of randomized outcome information. They do not reveal what an analysis would have found, and they cannot be converted into a conclusion about treatment efficacy or safety.
For biostatisticians and clinical researchers, another important feature is the difference between a stated objective and a reported primary outcome. The brief summary describes an evaluation of overall survival, whereas the listed primary outcome is treatment-emergent adverse events assessed by CTCAE v5.0. Both details matter, but neither creates an analyzed result. A reader must distinguish what the trial intended to investigate from what the registry reports as measured and analyzed.
Finally, the safety counts show why very small samples require careful language. Descriptive counts can identify what was recorded, but without an inferential analysis they do not quantify the precision of a group comparison. This record is a useful example of the boundary between reporting observations and making statistical claims.
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 principal limitation is that the registry states that no statistical analyses of efficacy or safety data were conducted. There are therefore no reported comparative estimates, confidence intervals, or test results for the primary outcome or overall survival. The serious adverse-event counts remain descriptive and cannot establish a treatment difference.
The number of patients screened and randomized was limited: the record reports 10 screened and 7 randomized, with 2 of those randomized discontinuing from the study. With so little information, the posted data offer a restricted account of outcomes and do not support broad conclusions about patients outside the trial. The record does not report the reasons for discontinuation or how subsequent outcome information was handled.
The study’s status is terminated, and the sponsor’s stated reason was non-safety reasons. The registry does not describe the circumstances behind termination beyond that characterization. It does not report a sample-size justification or a statistical plan, so the intended precision, analysis population, and handling of incomplete observations are not known from the registry record.
The primary outcome comprises several safety dimensions, but no single comparative analysis is reported. The term-level serious adverse-event percentages also lack enough detail in the record to determine whether terms overlapped within participants. These limitations prevent interpreting the figures as independent categories or as a full account of all treatment-emergent adverse events.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Trilaciclib, a CDK 4/6 Inhibitor, in Patients Receiving Docetaxel for Metastatic Non-Small Cell Lung Cancer (NSCLC) (PRESERVE 4) — NCT04863248.
- Registry record last updated 2023-04-14; status last verified 2023-01.
- Results first posted 2023-04-14.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
NCT04863248, PRESERVE 4, was a Phase 2 randomized, double-blind, parallel-group trial in metastatic NSCLC receiving docetaxel in the second- or third-line setting. It compared intravenous trilaciclib before docetaxel with placebo before docetaxel, given on Day 1 of each 21-day cycle. The registry lists treatment-emergent adverse events assessed by CTCAE v5.0 as the primary outcome.
The study is listed as terminated. The sponsor’s stated reason was non-safety reasons. The record reports 10 patients screened, 7 randomized, and 2 of those randomized discontinuing from the study. It provides serious adverse-event and death counts by arm, but states that no statistical analyses of efficacy or safety data were conducted.
Consequently, the registry record supplies descriptive study and safety information, but no analyzed comparative result for the primary outcome or overall survival.