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 (G1T28), a CDK 4/6 Inhibitor, in Combination With Etoposide and Carboplatin in Extensive Stage Small Cell Lung Cancer (SCLC) (NCT02499770), a randomized phase 1, phase 2 study. The primary outcome is Number of Participants With Dose Limiting Toxicities by Cohort in Cycle 1, Part 1.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02499770 |
| Phase | Phase 1, Phase 2 |
| Condition | Small Cell Lung Cancer |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 122 |
| Arms in the primary outcome | n/a |
| Lead sponsor | G1 Therapeutics, Inc. |
| Results posted | Yes |
2. Clinical Question
Population
Patients with newly diagnosed extensive-stage small cell lung cancer receiving first-line treatment. The registry describes the Part 1 safety population as enrolled participants who signed informed consent and received at least one dose of study drug.
Intervention
Trilaciclib (G1T28), administered before carboplatin and etoposide. Part 1 was a limited open-label, dose-finding portion that included trilaciclib cohorts.
Comparator
In Part 2, participants were randomized to trilaciclib or placebo before carboplatin and etoposide. Part 1 was not described as a randomized comparison.
Primary question
How many participants in each Part 1 cohort experienced a dose-limiting toxicity during days 1–21 of Cycle 1? The registry record defines these toxicities but does not report the primary endpoint results.
The study was intended to investigate whether trilaciclib could preserve bone marrow and the immune system, while also examining chemotherapy antitumor efficacy. Those aims describe the rationale; they are not findings. The primary endpoint is a safety measure in Part 1, whereas the Part 2 design adds a randomized, double-blind comparison of trilaciclib with placebo. The posted primary outcome is therefore not, by itself, a result of the randomized comparison.
The registry record lists small cell lung cancer as the condition and identifies carboplatin and etoposide as the chemotherapy backbone. It does not report a primary endpoint estimate, a comparison between Part 2 groups, or a confidence interval for the primary endpoint. Consequently, the clinical question can be described from the design and endpoint definition, but its answer cannot be determined from the posted primary outcome information.
3. Trial Design
This is a Phase 1b/2a study with two parts. Part 1 was a limited open-label dose-finding portion; Part 2 was randomized and double-blind, with a parallel-group design. In Part 1, participants received trilaciclib before carboplatin and etoposide. In Part 2, participants were randomized to trilaciclib or placebo before the same chemotherapy. Safety and tumor response were monitored, and the arm descriptions refer to tumor response assessment using RECIST version 1.1.
The registry record reports enrollment of 122. Its brief summary describes an approximate planned enrollment of 90, with 20 participants in Part 1 and 70 in Part 2. These are different registry entries: the approximate study description is not the same as the reported enrollment. The record identifies the study as completed and gives its start date as 2015-06-26 and primary completion date as 2017-07-03.
The primary outcome is the number of participants with dose-limiting toxicities by cohort in Cycle 1, Part 1, assessed during days 1–21. The registry also lists pharmacokinetic outcomes for trilaciclib and chemotherapy drugs, and neutropenia outcomes in Part 1. It reports 53 outcome measures. The record describes safety monitoring and tumor response assessment, but does not report the full statistical analysis plan, the method used to analyze the randomized Part 2 comparison, or the allocation ratio.
The endpoint description identifies a safety analysis set, including enrolled participants who signed informed consent and received at least one dose of study drug. Further detail about how participants were assigned to each analysis population is not reported in the registry record. The registry’s primary outcome information does not include the number of dose-limiting toxicities by cohort, so the endpoint cannot be interpreted as an observed result from the posted information.
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: Participants were screened within 14 days prior to first study drug administration. Informed consent and brain scans were obtained up to 28 days prior to first study drug administration. A total of 122 participants were enrolled (24 in Part 1 and 98 in Part 2), of which 96 were assigned to treatment.
Overall Study
| Stage | Part 1: Dose Finding/Expansion | Part 2: Trilaciclib/Placebo IV With E/P |
|---|---|---|
| STARTED | 19 | 77 |
| COMPLETED | 0 | 0 |
| NOT COMPLETED | 19 | 77 |
Reasons for not completing this period:
| Reason | Part 1: Dose Finding/Expansion | Part 2: Trilaciclib/Placebo IV With E/P |
|---|---|---|
| Death | 17 | 56 |
| Study completion | 1 | 10 |
| Withdrawal by Subject | 0 | 7 |
| Lost to Follow-up | 0 | 2 |
| Subject declined further treatment | 1 | 0 |
| Withdrawn by PI for compassionate reason | 0 | 1 |
| Randomized but not enrolled | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: Safety analysis set - included all enrolled participants (i.e., signed informed consent) who received at least 1 dose of study drug (etoposide, carboplatin, or trilaciclib). Part 1: Cohort 1 Trilaciclib 200 mg/m\^2 included 1 participant from Part 2 and 1 participant from Part 1 240 mg/m\^2 who received 200 mg/m\^2.
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: All participants randomized
| Characteristic | Unit | Part 1: Dose Finding/Expansion | Part 2: Trilaciclib/Placebo IV With E/P | Total |
|---|---|---|---|---|
| Participants analysed | 19 | 77 | 96 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 7 | 37 | 44 |
| Age, Categorical: >=65 years | Participants | 12 | 40 | 52 |
| Sex: Female, Male: Female | Participants | 8 | 23 | 31 |
| Sex: Female, Male: Male | Participants | 11 | 54 | 65 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 | 2 | 3 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 18 | 75 | 93 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 1 | 1 |
| Race (NIH/OMB): Asian | Participants | 0 | 1 | 1 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 3 | 1 | 4 |
| Race (NIH/OMB): White | Participants | 16 | 73 | 89 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 1 | 1 |
| Country: United States | Participants | 19 | 39 | 58 |
| Country: Non-United States | Participants | 0 | 38 | 38 |
| Body Surface Area | m^2 | 1.90 (SD 0.263) | 1.90 (SD 0.216) | NA (SD NA) |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants With Dose Limiting Toxicities by Cohort in Cycle 1, Part 1, measured over Days 1-21 of Cycle 1.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint counts participants with dose-limiting toxicities in each Part 1 cohort during days 1–21 of Cycle 1. The registry defines these as drug-related toxicities, including prolonged severe neutropenia, neutropenic infection or febrile neutropenia, serious thrombocytopenia, failure to meet blood-count recovery criteria for the next chemotherapy cycle, and certain severe nonhematologic toxicities. Toxicities not clearly related to etoposide or carboplatin were also considered when determining whether an event qualified.
A participant count is a binary-outcome summary: each participant either meets the endpoint definition during the specified period or does not. This can make the measure useful in dose-finding, where the frequency and nature of toxicity inform evaluation of a dose. General statistical point: counts are easiest to interpret alongside the number of participants assessed, because the same count can mean different things in groups of different sizes. The registry record does not report the primary endpoint counts or the number assessed for this endpoint by cohort.
The endpoint is restricted to Part 1 and to one treatment cycle. It does not directly summarize all later toxicities, overall safety, or tumor response. Nor does the endpoint definition establish that any particular toxicity occurred. Without the outcome counts and an analysis comparing cohorts, the posted record supports describing what was measured, but not estimating the observed frequency or drawing conclusions about dose differences.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record gives the design and endpoint definition but does not report the primary endpoint results. It therefore does not show how many participants experienced dose-limiting toxicities in the Part 1 cohorts. No effect estimate, uncertainty interval, or statistical test for that endpoint is reported in the registry record. The endpoint’s definition should not be mistaken for evidence that any listed toxicity occurred.
Part 1 and Part 2 answer different kinds of questions. Part 1 was an open-label dose-finding portion and the primary endpoint is a Cycle 1 safety count by cohort. Part 2 was randomized and double-blind, comparing trilaciclib with placebo alongside carboplatin and etoposide. The primary endpoint information presented in the registry does not provide an estimate of the Part 2 treatment contrast. Thus, the randomized design alone does not establish what the comparison found.
The adverse event information reports numbers at risk and affected for serious and other adverse events, as well as deaths, across four listed groups. These are descriptive counts. They should be read in the context of their group sizes and as safety summaries, not as adjusted comparisons or proof that an intervention caused an event. The registry does not report a causal analysis of these safety counts or uncertainty estimates for them.
The record lists 53 outcome measures, including pharmacokinetic outcomes, neutropenia measures, and the primary dose-limiting toxicity outcome. It does not report a full account of which outcomes were analyzed, how missing observations were handled, or how multiple outcome analyses were controlled. Those omissions limit the ability to evaluate the strength and precision of any conclusions from the registry entry.
General statistical point: an estimate describes the observed data, while an interval estimate conveys how much uncertainty remains around that estimate under the analysis assumptions. A test result alone would not establish clinical importance, and a non-significant result would not prove equivalence. In this record, the primary endpoint results and their uncertainty are not reported, so neither the magnitude nor precision of a primary endpoint finding can be assessed.
9. Statistical Methods Explained
What does a participant count represent?
The primary outcome is a count of participants meeting a defined dose-limiting toxicity criterion during a specified period. The endpoint is binary at the participant level: a person either meets the criteria or does not. General statistical point: a count can be presented descriptively, and a comparison may also consider the count relative to the number assessed. The registry defines the endpoint and identifies a safety analysis set, but the primary outcome counts by cohort are not reported.
Why does the study have two parts?
The record distinguishes an open-label dose-finding Part 1 from a randomized, double-blind Part 2. General statistical point: dose-finding and randomized comparisons have different aims and should not be treated as interchangeable analyses. A cohort-specific safety count from Part 1 does not answer the same question as a randomized comparison between Part 2 groups. The registry does not report a primary endpoint estimate for either a cohort contrast or the Part 2 comparison.
How should uncertainty be understood?
General statistical point: a confidence interval describes a range of values compatible with the observed data under the method’s assumptions. It helps readers judge precision as well as the direction and magnitude of an estimate. A wider interval indicates less precision than a narrower one, though the interval’s meaning depends on the statistical method and the data. No confidence interval for the primary endpoint is reported in the registry record, so its precision cannot be assessed from that outcome entry.
General statistical point: a p-value measures how unusual data at least as extreme as those observed would be under a specified null model. It is not the probability that the null hypothesis is true, and it does not measure the size or importance of an effect. The record does not report a primary endpoint p-value or the inferential method used for that outcome.
What do the planning assumptions mean?
The registry’s sample-size assumptions describe a planning illustration based on the observed effect, not the trial’s own design. The stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. General statistical point: such calculations illustrate how sample size depends on the effect a study aims to detect, the chosen error rate, and the allocation and analysis assumptions. They are not observed power and do not establish that the trial was designed or conducted using those assumptions. The registry record does not report the study’s own sample-size justification.
Planning illustrations are not outcome evidence. They do not show how many participants experienced toxicity or how precisely a treatment difference was estimated. The record does not give numerical planning results in the outcome information, so no planning sample size can be described from it.
What can the safety counts establish?
The adverse event summaries report participants at risk and affected, separated into serious and other adverse events, along with deaths. General statistical point: these counts describe events recorded in the listed groups. They do not, without an appropriate comparison and consideration of study design, establish that an intervention caused an event or that groups differ reliably. A formal comparison would need to specify the analysis population, outcome definition, treatment contrast, and uncertainty method. Those details are not reported for the adverse event counts.
General statistical point: over-dispersion matters when a statistical model assumes a particular level of variability but the observed data are more variable than that assumption allows. Ignoring extra variability can make uncertainty look too small. The registry record does not report an over-dispersion model for the primary endpoint, and no model should be assumed from the endpoint description alone.
The record reports 53 outcome measures and one analysis in its outcome information. That does not establish that a single statistical analysis was the only analysis conducted, nor does it describe the full analysis plan. The primary outcome is noted as involving several categories or time points and is not reduced to one comparison. The registry record does not report the methods used to select or combine those categories, or any adjustment for multiple testing.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists 53 outcome measures, spanning the primary dose-limiting toxicity outcome, pharmacokinetic measures, neutropenia measures, and other outcomes. When a study examines multiple outcomes, time points, or groups, the chance of finding at least one apparently notable result can increase. General statistical point: multiplicity procedures are methods for addressing that issue, but the appropriate approach depends on which outcomes are confirmatory and how they are analyzed.
The registry notes that the primary outcome has several categories or time points and is not reduced to one comparison. A method for controlling multiplicity, defining a testing hierarchy, or selecting among those categories is not reported in the registry record. The record also does not report enough analysis detail to determine which outcomes were designated for confirmatory inference.
Missing-data handling is not reported in the registry record. There is no description of how participants with missing endpoint assessments, incomplete follow-up, or unavailable measurements were treated in the primary analysis. The stated safety analysis set includes enrolled participants who signed informed consent and received at least one dose of study drug, but the record does not give a full account of analysis populations for all outcomes or clarify how that set relates to every analysis.
These omissions matter because exclusions and missing observations can affect both the estimate and its precision. General statistical point: complete-case analysis, imputation, and other approaches rely on different assumptions, so readers need the method and population definitions to judge their implications. No particular approach can be inferred from this registry entry.
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 |
|---|---|---|---|
| Part 1: Cohort 1 Trilaciclib 200 mg/m^2 | 4 | 12 | 33.3% |
| Part 1: Cohort 2 Trilaciclib 240mg/m^2 | 1 | 8 | 12.5% |
| Part 2: Placebo | 9 | 37 | 24.3% |
| Part 2: Trilaciclib 240 mg/m^2 | 11 | 38 | 28.9% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Part 1: Cohort 1 Trilaciclib 200 mg/m^2 | 9 of 12 |
| Part 1: Cohort 2 Trilaciclib 240mg/m^2 | 8 of 8 |
| Part 2: Placebo | 28 of 37 |
| Part 2: Trilaciclib 240 mg/m^2 | 28 of 38 |
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 |
|---|---|
| Part 1: Cohort 1 Trilaciclib 200 mg/m^2 | 12 of 12 |
| Part 1: Cohort 2 Trilaciclib 240mg/m^2 | 8 of 8 |
| Part 2: Placebo | 36 of 37 |
| Part 2: Trilaciclib 240 mg/m^2 | 37 of 38 |
Most frequent serious adverse event terms
| Event term | Organ system | Part 1: Cohort 1 Trilaciclib 200 mg/m^2 | Part 1: Cohort 2 Trilaciclib 240mg/m^2 | Part 2: Placebo | Part 2: Trilaciclib 240 mg/m^2 |
|---|---|---|---|---|---|
| Pneumonia | Infections and infestations | 1 of 12 | 0 of 8 | 1 of 37 | 2 of 38 |
| Respiratory failure | Respiratory, thoracic and mediastinal disorders | 0 of 12 | 0 of 8 | 1 of 37 | 2 of 38 |
| Febrile neutropenia | Blood and lymphatic system disorders | 0 of 12 | 0 of 8 | 1 of 37 | 1 of 38 |
| Anemia | Blood and lymphatic system disorders | 0 of 12 | 0 of 8 | 2 of 37 | 0 of 38 |
| Epilepsy | Nervous system disorders | 0 of 12 | 0 of 8 | 1 of 37 | 1 of 38 |
| Deep vein thrombosis | Vascular disorders | 0 of 12 | 0 of 8 | 1 of 37 | 0 of 38 |
| Cardiac failure chronic | Cardiac disorders | 0 of 12 | 1 of 8 | 0 of 37 | 0 of 38 |
| Acute myocardial infarction | Cardiac disorders | 0 of 12 | 0 of 8 | 1 of 37 | 0 of 38 |
| Atrial fibrillation | Cardiac disorders | 0 of 12 | 0 of 8 | 1 of 37 | 0 of 38 |
| Myocardial infarction | Cardiac disorders | 1 of 12 | 0 of 8 | 0 of 37 | 0 of 38 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Part 1: Cohort 1 Trilaciclib 200 mg/m^2 | Part 1: Cohort 2 Trilaciclib 240mg/m^2 | Part 2: Placebo | Part 2: Trilaciclib 240 mg/m^2 |
|---|---|---|---|---|---|
| Neutropenia | Blood and lymphatic system disorders | 5 of 12 | 5 of 8 | 23 of 37 | 9 of 38 |
| Fatigue | General disorders | 7 of 12 | 4 of 8 | 6 of 37 | 16 of 38 |
| Anemia | Blood and lymphatic system disorders | 5 of 12 | 1 of 8 | 15 of 37 | 10 of 38 |
| Nausea | Gastrointestinal disorders | 5 of 12 | 4 of 8 | 8 of 37 | 13 of 38 |
| Thrombocytopenia | Blood and lymphatic system disorders | 3 of 12 | 2 of 8 | 10 of 37 | 10 of 38 |
| Constipation | Gastrointestinal disorders | 4 of 12 | 4 of 8 | 8 of 37 | 9 of 38 |
| Alopecia | Skin and subcutaneous tissue disorders | 5 of 12 | 3 of 8 | 11 of 37 | 6 of 38 |
| Dyspnea | Respiratory, thoracic and mediastinal disorders | 2 of 12 | 3 of 8 | 5 of 37 | 8 of 38 |
| Diarrhea | Gastrointestinal disorders | 3 of 12 | 2 of 8 | 7 of 37 | 6 of 38 |
| Vomiting | Gastrointestinal disorders | 4 of 12 | 4 of 8 | 5 of 37 | 3 of 38 |
Serious events with the highest arm-level rate: cardiac failure chronic (12.5%), stomatitis (12.5%), oral candidiasis (12.5%), myocardial infarction (8.3%), bone pain (8.3%).
The posted safety summaries list four groups: Part 1 Cohort 1 trilaciclib 200 mg/m^2, Part 1 Cohort 2 trilaciclib 240mg/m^2, Part 2 placebo, and Part 2 trilaciclib 240 mg/m^2. For each group, the record gives participants at risk and affected for serious adverse events and other adverse events, as well as deaths. These are counts, not adjusted treatment effects.
The serious adverse event counts are 4 of 12, 1 of 8, 9 of 37, and 11 of 38, respectively, for the four listed groups. The corresponding counts at risk are 12, 8, 37, and 38. The deaths reported are 9, 8, 28, and 28, respectively. The registry also lists other adverse event counts: 12 of 12, 8 of 8, 36 of 37, and 37 of 38. No causal interpretation or statistical comparison for these counts is reported.
The record lists serious adverse event terms with percentages, including Cardiac failure chronic, Stomatitis, and Oral candidiasis at 12.5%, and Myocardial infarction, Bone pain, and Pneumonia at 8.3%. The listed terms should be read as the registry’s serious-event summary; the record does not specify in this entry how these percentages map to individual groups.
General statistical point: event counts are descriptive and can be influenced by follow-up and the number of participants observed. The posted counts alone do not establish treatment causation or a difference between groups.
12. What the Result Does, and Does Not, Mean
The registry record establishes that the study examined trilaciclib before carboplatin and etoposide in a two-part design, with an open-label dose-finding portion and a randomized, double-blind portion. It also defines the primary endpoint as a count of participants with dose-limiting toxicities in Part 1 during days 1–21 of Cycle 1. These details explain the study question and what the primary endpoint was intended to capture.
The record does not report the primary endpoint outcome counts by cohort. It therefore cannot establish how often dose-limiting toxicities occurred in Part 1, whether the cohorts differed, or how precise any estimated difference might be. It also does not report a treatment-effect estimate for the randomized Part 2 comparison in the primary outcome information. A randomized design describes how treatment assignment was planned; it is not itself a result.
The adverse event figures provide descriptive counts across the listed groups. They do not, by themselves, show whether an event was caused by trilaciclib, placebo, or chemotherapy. The listed deaths likewise cannot be interpreted as comparative survival results: no survival analysis or treatment effect is reported in the record summarized by these safety counts.
The study’s stated aim included investigation of marrow and immune-system preservation and chemotherapy antitumor efficacy. A stated aim is not evidence that those objectives were achieved. The posted information identifies safety, pharmacokinetic, neutropenia, and tumor-response monitoring, but does not report enough results to determine efficacy, comparative safety, or the size and precision of treatment effects.
General statistical point: absence of a reported result is not evidence of no effect, and an observed difference in descriptive counts would not alone establish a reliable or clinically important effect. Interpretation requires the estimates, their uncertainty, defined analysis populations, and the methods used to compare groups. Those elements are not reported for the primary endpoint in this registry record.
13. Why This Trial Matters Statistically
This study raises a useful statistical distinction between dose-finding and randomized evaluation. Part 1 focused on dose cohorts and a safety endpoint, while Part 2 used randomization and blinding to compare trilaciclib with placebo alongside chemotherapy. Keeping those purposes separate prevents a cohort safety count from being mistaken for evidence from the randomized comparison.
The primary endpoint also illustrates why an endpoint definition is not a result. The registry specifies a time window and a set of toxicity criteria, including hematologic and nonhematologic events. Those rules make clear what was meant to count as a dose-limiting toxicity. However, without the cohort counts and the number assessed, readers cannot evaluate the observed frequency or its precision.
The record lists a broad set of outcome measures, including pharmacokinetic and neutropenia outcomes, and reports adverse event counts across four groups. This breadth makes clear why transparent analysis populations, missing-data procedures, and multiplicity methods are important. The registry does not report those methods in enough detail to evaluate their use across outcomes.
The entry also distinguishes an approximate planned enrollment described in the brief summary from the enrollment reported in the registry. Keeping planned and reported enrollment distinct is important when interpreting study size. Neither number, by itself, describes the number included in a particular endpoint analysis.
Overall, the statistical value of the record is in documenting the design, endpoint definition, and descriptive safety information. It does not provide the primary endpoint results or a reported randomized treatment-effect estimate, so statistical conclusions about the main questions remain unavailable from the posted information.
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.
A central limitation is that the registry record does not report the primary endpoint counts by Part 1 cohort. It therefore provides no estimate of the frequency of dose-limiting toxicity and no precision measure for that endpoint. The registry also does not report a primary endpoint comparison or its analysis method.
The record describes Part 2 as randomized and double-blind, but the primary outcome information does not provide the randomized comparison’s treatment-effect estimate. The allocation ratio and detailed randomization procedures are not reported in the registry record. The Part 1 cohort safety outcome should not be used as a substitute for a Part 2 comparison.
The brief summary describes an approximate planned enrollment of 90, with 20 in Part 1 and 70 in Part 2, while the registry reports enrollment of 122. The record does not explain the difference between the approximate planned enrollment and the reported enrollment. It also does not state the number analyzed for each outcome in the information available for the primary endpoint.
Although the registry lists 53 outcome measures, detailed results and analysis methods are not reported for all of them in the record. Missing-data methods, multiplicity control, and a full account of analysis populations are not reported. This limits assessment of outcome selection, precision, and possible bias from missing observations.
The adverse event information is descriptive, and the record does not report adjusted comparisons, uncertainty estimates, or a causal analysis for those counts. The listed serious-event percentages are not linked to individual groups in the record. Follow-up duration for interpreting the death counts is also not reported in the safety summary.
These limitations restrict what can be concluded from the registry entry; they do not establish that analyses or results were absent from other sources.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Trilaciclib (G1T28), a CDK 4/6 Inhibitor, in Combination With Etoposide and Carboplatin in Extensive Stage Small Cell Lung Cancer (SCLC) — NCT02499770.
- Registry record last updated 2020-08-21; status last verified 2020-08.
- Results first posted 2020-07-09.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT02499770 is a completed Phase 1b/2a study of trilaciclib with carboplatin and etoposide in extensive-stage small cell lung cancer. It included an open-label dose-finding Part 1 and a randomized, double-blind Part 2 comparing trilaciclib with placebo before chemotherapy. The registry reports enrollment of 122 and identifies the primary endpoint as the number of participants with dose-limiting toxicities by cohort in Part 1 during days 1–21 of Cycle 1.
The registry defines the primary endpoint and reports descriptive adverse event counts across four groups, but does not report the primary endpoint results by cohort or a treatment-effect estimate for the randomized comparison in the outcome information described. The statistical analysis plan, missing-data procedures, and multiplicity methods are not reported in the registry record.