Trilaciclib (G1T28), a CDK 4/6 Inhibitor, in Combination With Etoposide and Carboplatin in Extensive Stage Small Cell Lung Cancer (SCLC)

Small Cell Lung Cancer Clinical Trial

Official title:

Phase 1b/2a Safety and Pharmacokinetic Study of G1T28 in Patients With Extensive Stage Small Cell Lung Cancer (SCLC) Receiving Etoposide and Carboplatin

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02499770
• Other study ID #: G1T28-02
• Secondary ID: 2016-001583-11
• Status: Completed
• Phase: Phase 1/Phase 2
• Start date: June 26, 2015
• Est. completion date: February 22, 2019

Study information

• Verified date: August 2020
• Source: G1 Therapeutics, Inc.
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

This is a study to investigate the potential clinical benefit of trilaciclib (G1T28) in preserving the bone marrow and the immune system, and enhancing chemotherapy antitumor efficacy when administered prior to carboplatin and etoposide in first line treatment for patients with newly diagnosed extensive-stage SCLC.

The study consists of 2 parts: a limited open-label, dose-finding portion (Part 1), and a randomized double-blind portion (Part 2). Both parts include 3 study phases: Screening Phase, Treatment Phase, and Survival Follow-up Phase. The Treatment Phase begins on the day of first dose with study treatment and completes at the Post-Treatment Visit. Approximately, 90 patients will be enrolled in the study; 20 patients in the Part 1 and 70 patients in the Part 2 portion.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 122
• Est. completion date: February 22, 2019
• Est. primary completion date: July 3, 2017
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Male or female subjects aged =18 years

• Unequivocally confirmed diagnosis of SCLC by histology or cytology, preferably including the presence of neuroendocrine features by immunohistochemistry

• At least 1 target lesion that is unirradiated and measurable by RECIST, Version 1.1

• Eastern Cooperative Oncology Group (ECOG) performance status of 0 - 2

• Adequate organ function

Exclusion Criteria:

• Prior chemotherapy for extensive-stage SCLC

• Presence of symptomatic brain metastases requiring immediate treatment with radiation therapy or steroids.

• Uncontrolled ischemic heart disease or uncontrolled symptomatic congestive heart failure

• Known history of stroke or cerebrovascular accident within 6 months prior to enrollment

• Other uncontrolled serious chronic disease or conditions that in the investigator's opinion could affect compliance or follow-up in the protocol

• Concurrent radiotherapy to any site or radiotherapy within 2 weeks prior to enrollment or previous radiotherapy to the target lesion sites (the sites that are to be followed for determination of a response)

• Receipt of any investigational medication within 4 weeks prior to enrollment

Related Conditions & MeSH terms

• Lung Neoplasms
• Small Cell Lung Cancer
• Small Cell Lung Carcinoma

Intervention

Drug:
• Carboplatin

• Placebo

• Trilaciclib

• Etoposide

Locations

Country	Name	City	State
France	CHU de Rennes Hopital Pontchaillou	Rennes
Georgia	ARENSIA Exploratory Medicine LLC	Tbilisi
Hungary	Orszagos Koranyi Tbc es Pulmonologiai Intezet, XI. Tudobelosztaly	Budapest
Hungary	Veszprem Megyei Tudogyogyintezet	Farkasgyepu	Veszprem
Hungary	Hetenyi Geza Korhaz	Szolnok
Moldova, Republic of	ARENSIA Exploratory Medicine Phase I Unit, The Institute of Oncology	Chisinau
Poland	Samodzielny Publiczny ZespAA GruAicy i ChorAb PA¿uc	Olsztyn
Poland	Wojewodzki Szpital Zespolony im. L. Rydygiera	Torun
Poland	Centrum Onkologii-Instytut im. Marii Sklodowskiej-Curie	Warszawa
Spain	Hospital de la Santa Creu i Sant Pau	Barcelona
Spain	Consorcio Hospitalario Provincial	Castillón
Spain	Fundacion Jimenez Diaz	Madrid
Spain	Hgu Gregorio Maranon	Madrid
Spain	Hospital Regional Universitario HRU Carlos Haya Malaga	Malaga	Andalucia
United States	University of New Mexico Comprehensive Cancer Center	Albuquerque	New Mexico
United States	University Cancer and Blood Center, LLC	Athens	Georgia
United States	Emory University	Atlanta	Georgia
United States	Center For Cancer and Blood Disorders	Bethesda	Maryland
United States	Boca Raton Regional Hospital - Lynn Cancer Institute	Boca Raton	Florida
United States	Roswell Park	Buffalo	New York
United States	UNC - Lineberger Comprehensive Cancer Center	Chapel Hill	North Carolina
United States	Memorial Hospital - Univ. of Colorado Health	Colorado Springs	Colorado
United States	University of Colorado Health, Oncology Clinical Research Northern Region	Fort Collins	Colorado
United States	Florida Cancer Specialists - South	Fort Myers	Florida
United States	Greenville Health System	Greenville	South Carolina
United States	Genesis Cancer Center	Hot Springs	Arkansas
United States	Hanna Cancer Associates - University of Tennessee	Knoxville	Tennessee
United States	Tennessee Cancer Specialists	Knoxville	Tennessee
United States	Norris Cotton Cancer Center	Lebanon	New Hampshire
United States	Norton Cancer Institute	Louisville	Kentucky
United States	Oklahoma University - Peggy and Charles Stephenson Cancer Center	Oklahoma City	Oklahoma
United States	Thomas Jefferson University	Philadelphia	Pennsylvania
United States	Highlands Oncology Group	Rogers	Arkansas
United States	Guthrie Medical Group, PC	Sayre	Pennsylvania
United States	Gibbs Cancer Center	Spartanburg	South Carolina
United States	Florida Cancer Specialists - North	Tavares	Florida
United States	Texas Oncology	Tyler	Texas
United States	Northwest Cancer Specialists, P.C.	Vancouver	Washington
United States	Florida Cancer Specialists - East	West Palm Beach	Florida
United States	The Oncology Institute of Hope and Innovation	Whittier	California

Sponsors (1)

Lead Sponsor	Collaborator
G1 Therapeutics, Inc.

Countries where clinical trial is conducted

United States,  France,  Georgia,  Hungary,  Moldova, Republic of,  Poland,  Spain, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Number of Participants With Dose Limiting Toxicities by Cohort in Cycle 1, Part 1	Dose-limiting toxicities (DLTs) were drug-related toxicities defined as follows: Absolute neutrophil count (ANC) < 0.5 × 10^9/L lasting for = 7 days; = Grade 3 neutropenic infection/febrile neutropenia; Grade 4 thrombocytopenia (TCP) or = Grade 3 TCP with bleeding; Unable to start next cycle of chemotherapy due to lack of recovery to an ANC = 1.5 × 10^9/L and platelet count = 100 × 10^9/L; = Grade 3 nonhematologic toxicity (nausea, vomiting, and diarrhea failing maximal medical management; fatigue lasting for > 72 hours); Toxicities not clearly related to etoposide/carboplatin therapy were also considered for the purposes of determining DLTs.	Days 1-21 of Cycle 1
Primary	Incidence of Treatment-emergent Adverse Events (TEAEs), Serious Adverse Events (SAEs), Related AEs, Related SAEs, and AEs Leading to Study Drug Discontinuation in Part 1	An AE was defined as any untoward medical occurrence in a participant administered a medicinal product that did not necessarily have a causal relationship with this treatment. TEAEs were defined as any AE that started on or after the first dose of study drug and up to the last dose +30 days. SAEs were defined as any untoward medical occurrence that at any dose resulted in death, was life threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity or was a congenital anomaly/birth defect. Relatedness to study drug was assessed by the investigator. Related refers to those events that were Possibly, Probably, or Definitely Related. AEs with an unknown/not reported onset date were also included.	TEAEs were any AE that started on or after the first dose of study drug and up to the last dose +30 days (a minimum of 51 days up to a maximum of 374 days)
Primary	Duration of Severe (Grade 4) Neutropenia in Part 2	Severe (Grade 4) neutropenia was defined as at least 1 ANC value <0.5 × 10^9/L during the treatment period. Within each cycle, the duration (days) of severe neutropenia was defined as the number of days from the date of the first ANC value of <0.5 × 10^9/L observed between start of cycle and end of cycle to the date of the first ANC value =0.5 × 10^9/L that met the following criteria: 1) occurred after the ANC value of <0.5 × 10^9/L and 2) no other ANC values <0.5 × 10^9/L occurred between this day and end of cycle. The duration of severe neutropenia only included participants who had at least 1 severe neutropenia event in the cycle, and censoring rules were applied for unresolved severe neutropenia in a cycle. For the treatment period, the overall duration of severe neutropenia was the median value among the durations from all cycles.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Maximum Observed Plasma Concentration (Cmax) of Trilaciclib in Cycle 1, Part 1	Cmax of trilaciclib in plasma was determined from individual concentration-time data by non-compartmental analysis methods. The actual sampling times in relation to dosing were used. For estimation of Cmax, a concentration that was below the limit of quantification (BLQ) was assigned a value of zero if it occurred in a profile before the first measurable concentration. If a BLQ value occurred after a measurable concentration in a profile, and was followed by a value above the lower limit of quantification, then the BLQ was treated as missing data. If a BLQ value occurred at the end of the collection interval (after the last quantifiable concentration) it was treated as missing data. If two BLQ values occurred in succession after Cmax, the profile was deemed to have terminated at the first BLQ value and any subsequent concentrations were omitted.	Days 1 and 3 of Cycle 1 for a 21-day cycle
Secondary	Area Under the Plasma Concentration Versus Time Curve From Time Zero Extrapolated to Infinity (AUC0-inf) for Trilaciclib in Cycle 1, Part 1	AUC0-inf of trilaciclib in plasma was determined from individual concentration-time data by non-compartmental analysis methods. The actual sampling times in relation to dosing were used.	Days 1 and 3 of Cycle 1 for a 21-day cycle
Secondary	Time of Maximum Observed Concentration (Tmax) of Trilaciclib in Cycle 1, Part 1	Tmax of trilaciclib in plasma was determined from individual concentration-time data by non-compartmental analysis methods. The actual sampling times in relation to dosing were used.	Days 1 and 3 of Cycle 1 for a 21-day cycle
Secondary	Cmax of Etoposide and Free and Total Carboplatin in Cycle 1, Part 1	Cmax of etoposide and free and total carboplatin in plasma were determined from individual concentration-time data by non-compartmental analysis methods. The actual sampling times in relation to dosing were used. For estimation of Cmax, a concentration that was BLQ was assigned a value of zero if it occurred in a profile before the first measurable concentration. If a BLQ value occurred after a measurable concentration in a profile, and was followed by a value above the lower limit of quantification, then the BLQ was treated as missing data. If a BLQ value occurred at the end of the collection interval (after the last quantifiable concentration) it was treated as missing data. If two BLQ values occurred in succession after Cmax, the profile was deemed to have terminated at the first BLQ value and any subsequent concentrations were omitted.	Days 1 and 3 of Cycle 1 for a 21-day cycle (carboplatin was only dosed on Day 1 so there are no Day 3 Cmax values)
Secondary	AUC0-inf of Etoposide and Free and Total Carboplatin in Cycle 1, Part 1	AUC0-inf of etoposide and free and total carboplatin in plasma were determined from individual concentration-time data by non-compartmental analysis methods. The actual sampling times in relation to dosing were used.	Days 1 and 3 of Cycle 1 for a 21-day cycle (carboplatin was only dosed on Day 1 so there are no Day 3 AUC0-inf values)
Secondary	Tmax of Etoposide and Free and Total Carboplatin in Cycle 1, Part 1	Tmax of etoposide and free and total carboplatin in plasma was determined from individual concentration-time data by non-compartmental analysis methods. The actual sampling times in relation to dosing were used.	Days 1 and 3 of Cycle 1 for a 21-day cycle (carboplatin was only dosed on Day 1 so there are no Day 3 Tmax values)
Secondary	Duration of Severe (Grade 4) Neutropenia in Part 1	Severe (Grade 4) neutropenia was defined as at least 1 ANC value <0.5 × 10^9/L during the treatment period. Within each cycle, the duration (days) of severe neutropenia was defined as the number of days from the date of the first ANC value of <0.5 × 10^9/L observed between start of cycle and end of cycle to the date of the first ANC value =0.5 × 10^9/L that met the following criteria: 1) occurred after the ANC value of <0.5 × 10^9/L and 2) no other ANC values <0.5 × 10^9/L occurred between this day and end of cycle. The duration of severe neutropenia only included participants who had at least 1 severe neutropenia event in the cycle, and censoring rules were applied for unresolved severe neutropenia in a cycle. For the treatment period, the overall duration of severe neutropenia was the median value among the durations from all cycles.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Severe (Grade 4) Neutropenia in Part 1	Severe (Grade 4) neutropenia was defined as at least 1 ANC value <0.5 × 10^9/L during the treatment period.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Febrile Neutropenia in Part 1	Each febrile neutropenia event (as defined by Common Terminology Criteria for Adverse Events [CTCAE]) was captured as an AE. The occurrence of febrile neutropenia was defined as at least 1 febrile neutropenia event during the treatment period. For the treatment period, the total number of febrile neutropenia events was the number of febrile neutropenia events with a unique start date.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Duration of Grade 3/4 Neutropenia in Part 1	Grade 3/4 neutropenia was defined as at least 1 ANC value <1.0 × 10^9/L during the treatment period. Within each cycle, duration (days) of Grade 3/4 neutropenia was defined as the number of days from the date of the first ANC value of <1.0 × 10^9/L observed between start of cycle and end of cycle to the date of the first ANC value =1.0 × 10^9/L that met the following criteria: 1) occurred after the ANC value of <1.0 × 10^9/L and 2) no other ANC values <1.0 × 10^9/L occurred between this day and end of cycle. The duration of Grade 3/4 neutropenia only included participants who had at least 1 Grade 3/4 neutropenia event in the cycle, and censoring rules were applied for unresolved Grade 3/4 neutropenia in a cycle. For the treatment period, the overall duration of Grade 3/4 neutropenia was the median value among the durations of Grade 3/4 neutropenia from all cycles.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Grade 3/4 Neutropenia in Part 1	Grade 3/4 neutropenia was defined as at least 1 ANC value <1.0 × 10^9/L during the treatment period.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Nadir of Absolute Neutrophil Count in Cycle 1, Part 1	Cycle nadir was the lowest value for ANC that occurred between start of cycle and end of cycle and was less than the cycle baseline.	From baseline to the end of Cycle 1
Secondary	Occurrence of Granulocyte-Colony Stimulating Factor (G-CSF) Administration in Part 1	Administration of G-CSF was collected with concomitant medications, which were coded using World Health Organization Drug Dictionary (WHO-DD) Version September 2017. A cycle where G-CSF was administered concurrently was identified by comparing the start and stop dates of each administration of G-CSF to the start of cycle and end of cycle. The occurrence of G-CSF administrations was defined as at least 1 cycle with G-CSF administrations during the treatment period. For the treatment period, the total number of G-CSF administrations was the number of cycles with G-CSF administrations.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Red Blood Cell (RBC) Transfusion in Part 1	Within a cycle, a RBC transfusion event was defined as either 1) an actual RBC transfusion, or 2) eligible for RBC transfusion (defined as hemoglobin <8.0 g/dL). The occurrence of RBC transfusions was defined as at least 1 cycle with RBC transfusion during the treatment period. For the treatment period, the total number of RBC transfusions was the number of cycles with RBC transfusions.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Change From Baseline of Hemoglobin at the End of Cycle 6, Part 1	Blood samples were collected for local clinical laboratory assessment of hemoglobin levels.	Baseline, Day 1, Day 3, Day 8, Day 10, and Day 15 of a 21-day cycle x 6
Secondary	Occurrence of Erythropoietin Stimulating Agent (ESA) Administration in Part 1	Administration of ESAs was collected with concomitant medications, which were coded using WHO-DD Version September 2017. A cycle where an ESA was administered concurrently was identified by comparing the start and stop dates of each administration of an ESA to the start of cycle and end of cycle. The occurrence of ESA administration was at least 1 cycle with an ESA administration during the treatment period. For the treatment period, the total number of ESA administrations was the number of cycles with ESA administrations.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Platelet Transfusion in Part 1	Within a cycle, a platelet transfusion event was defined as either 1) an actual platelet transfusion, or 2) eligible for platelet transfusion (defined as a platelet count =10 × 10^9/L). The occurrence of platelet transfusions was defined as at least 1 cycle with platelet transfusion during the treatment period. For the treatment period, the total number of platelet transfusions was the number of cycles with platelet transfusions.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Change From Baseline of Platelet Count at the End of Cycle 6, Part 1	Blood samples were collected for local clinical laboratory assessment of platelet count.	Baseline, Day 1, Day 3, Day 8, Day 10, and Day 15 of a 21-day cycle x 6
Secondary	Change From Baseline of Lymphocyte Count at the End of Cycle 6, Part 1	Blood samples were collected for local clinical laboratory assessment of lymphocyte count.	Baseline, Day 1, Day 3, Day 8, Day 10, and Day 15 of a 21-day cycle x 6
Secondary	Occurrence of Dose Reduction in Part 1	Dose reductions were not permitted for trilaciclib, per study protocol. Dose reductions for E/P were derived from changes in the protocol-specified dose on the dosing page and corresponded to the reductions for toxicity specified in the protocol. No more than 2 dose reductions of E/P in total were allowed for any participant. Simultaneous reductions in the doses of E/P were counted as 1 dose reduction. For the treatment period, the total number of dose reductions was the number of cycles where there was at least 1 dose reduction.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Infectious SAEs in Part 1	SAEs were defined as any untoward medical occurrence that at any dose resulted in death, was life threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity or was a congenital anomaly/birth defect. An infectious SAE was a serious event in the Medical Dictionary for Regulatory Activities (MedDRA) system organ class "infections and infestations" and a preferred term of anal abscess, bacteraemia, bronchitis, candida infection, chronic sinusitis, conjunctivitis, infection, influenza, nasopharyngitis, oral candidiasis, oral herpes, pharyngitis streptococcal, pneumonia, pneumonia bacterial, respiratory tract infection, sepsis, skin infection, upper respiratory tract infection, urinary tract infection, urosepsis or viral upper respiratory tract infection.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Pulmonary Infection SAE in Part 1	SAEs were defined as any untoward medical occurrence that at any dose resulted in death, was life threatening, requires inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity or was a congenital anomaly/birth defect. A pulmonary infection SAE was a serious event in the MedDRA system organ class "infections and infestations" and a preferred term of bronchitis, influenza, pneumonia, pneumonia bacterial, respiratory tract infection, upper respiratory tract infection or viral upper respiratory tract infection.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of IV Antibiotic Administration in Part 1	Intravenous antibiotic administration was collected with concomitant medications, which were coded using WHO-DD Version September 2017. A cycle where IV antibiotic was administered concurrently was identified by comparing the start and stop dates of each administration of IV antibiotic to the start of cycle and end of cycle. The occurrence of IV antibiotic administration was defined as at least 1 cycle with IV antibiotic administration during the treatment period. For the treatment period, the total number of IV antibiotic administrations was the number of cycles with IV antibiotic administrations.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Time to First Major Adverse Hematologic Event (MAHE) in Part 1	MAHE was a composite endpoint incorporating the measurement of several clinically meaningful aspects of myelopreservation into a single endpoint. The individual components for MAHE were hospitalization for a hematologic event, febrile neutropenia, death related to treatment, dose delay/reduction due to ANC or platelet counts, prolonged severe neutropenia (duration >5 days), RBC transfusion (actual or eligible) and platelet transfusion (actual or eligible). Time to first occurrence of a MAHE event was defined as the first time to observe an interested event among all the components, starting from the first dose date of study drug administration.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Best Overall Tumor Response Based on Assessments in Part 1	Tumor response was assessed by computed tomography (CT) or magnetic resonance imaging (MRI). Overall visit response by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1 was derived programmatically using data from target lesions (TLs), non-target lesions (NTLs), & new lesions. Tumor response data were used to determine each participant's time point response & best overall response (BOR). Complete response (CR) was disappearance of all TLs, any pathological lymph nodes selected as TLs must have reduced in short axis to <10 mm. Partial response (PR) was at least a 30% decrease from baseline in the sum of diameters of TLs, as long as criteria for progressive disease (PD) were not met. PD was a =20% increase in the smallest sum of diameters of TLs since treatment started (including baseline) and an absolute increase of =5 mm. Stable disease (SD) was neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD.	Baseline, end of every two 21-day cycles, up until disease progression to a maximum of the time at least 70% overall survival (OS) events observed (a maximum of 4 years)
Secondary	Best Overall Tumor Response Based on Blinded Independent Central Review (BICR) Assessments in Part 1	Tumor response was assessed by CT or MRI. Overall visit response by RECIST v1.1 was determined by BICR. Tumor response data were used to determine each participant's time point response & BOR. CR was disappearance of all TLs, any pathological lymph nodes selected as TLs must have reduced in short axis to <10 mm. PR was at least a 30% decrease from baseline in the sum of diameters of TLs, as long as criteria for PD were not met. PD was a =20% increase in the smallest sum of diameters of TLs since treatment started (including baseline) and an absolute increase of =5 mm. SD was neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD.	Baseline, end of every two 21-day cycles, up until disease progression to a maximum of the time at least 70% OS events observed (a maximum of 4 years)
Secondary	Progression Free Survival (PFS) Based on Assessments in Part 1	Tumor response was assessed by CT or MRI. PFS was defined as the time (months) from date of first dose date of study drug for participants in Part 1 until date of documented disease progression or death due to any cause, whichever occurred first. More specifically, PFS was determined using all the assessment data up until the last evaluable visit prior to or on the date of i) disease progression as defined by RECIST 1.1 or by clinical criteria as determined by the investigator; or ii) withdrawal of consent; or iii) receiving subsequent anticancer therapy, whichever was earlier. For PFS determined using response data derived programmatically, either clinical progression or progression by RECIST (whichever came first) was considered. Median and inter-quartile range of PFS were calculated using the Kaplan-Meier method.	Baseline, end of every two 21-day cycles, up until disease progression to a maximum of the time at least 70% OS events observed (a maximum of 4 years)
Secondary	OS in Part 1	OS was calculated as the time (months) from date of first dose of study drug for participants in Part 1 to the date of death due to any cause. Participants who did not die during the study were censored at the date last known to be alive. Participants lacking data beyond the day of first dose of study drug had their survival time censored at day of first dose of study drug. OS was not censored if a participant received other anti-tumor treatments after the study drugs. Median and inter-quartile range of OS were calculated using the Kaplan-Meier method.	Baseline up until death or a maximum of the time at least 70% OS events observed (a maximum of 4 years)
Secondary	Occurrence of Severe (Grade 4) Neutropenia in Part 2	Severe (Grade 4) neutropenia was defined as at least 1 ANC value <0.5 × 10^9/L during the treatment period.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Febrile Neutropenia in Part 2	Each febrile neutropenia event (as defined by CTCAE) was captured as an AE. The occurrence of febrile neutropenia was defined as at least 1 febrile neutropenia event during the treatment period. For the treatment period, the total number of febrile neutropenia events was the number of febrile neutropenia events with a unique start date.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Duration of Grade 3/4 Neutropenia in Part 2	Grade 3/4 neutropenia was defined as at least 1 ANC value <1.0 × 10^9/L during the treatment period. Within each cycle, duration (days) of Grade 3/4 neutropenia was defined as the number of days from the date of the first ANC value of <1.0 × 10^9/L observed between start of cycle and end of cycle to the date of the first ANC value =1.0 × 10^9/L that met the following criteria: 1) occurred after the ANC value of <1.0 × 10^9/L and 2) no other ANC values <1.0 × 10^9/L occurred between this day and end of cycle. The duration of Grade 3/4 neutropenia only included participants who had at least 1 Grade 3/4 neutropenia event in the cycle, and censoring rules were applied for unresolved Grade 3/4 neutropenia in a cycle. For the treatment period, the overall duration of Grade 3/4 neutropenia was the median value among the durations of Grade 3/4 neutropenia from all cycles.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Grade 3/4 Neutropenia in Part 2	Grade 3/4 neutropenia was defined as at least 1 ANC value <1.0 × 10^9/L during the treatment period.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Nadir of Absolute Neutrophil Count in Cycle 1, Part 2	Cycle nadir was the lowest value for ANC that occurred between start of cycle and end of cycle and was less than the cycle baseline.	From baseline to the end of Cycle 1
Secondary	Occurrence of G-CSF Administration in Part 2	Administration of G-CSF was collected with concomitant medications, which were coded using WHO-DD Version September 2017. A cycle where G-CSF was administered concurrently was identified bycomparing the start and stop dates of each administration of G-CSF to the start of cycle and end of cycle. The occurrence of G-CSF administrations was defined as at least 1 cycle with G-CSF administrations during the treatment period. For the treatment period, the total number of G-CSF administrations was the number of cycles with G-CSF administrations.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of RBC Transfusion in Part 2	Within a cycle, a RBC transfusion event was defined as either 1) an actual RBC transfusion, or 2) eligible for RBC transfusion (defined as hemoglobin <8.0 g/dL). The occurrence of RBC transfusions was defined as at least 1 cycle with RBC transfusion during the treatment period. For the treatment period, the total number of RBC transfusions was the number of cycles with RBC transfusions. If a participant did not have any RBC transfusions, they were assigned a value of 0.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Change From Baseline of Hemoglobin at the End of Cycle 6, Part 2	Blood samples were collected for local clinical laboratory assessment of hemoglobin levels.	Baseline, Day 1, Day 3, Day 8, Day 10, and Day 15 of a 21-day cycle x 6
Secondary	Occurrence of ESA Administration in Part 2	Administration of ESAs was collected with concomitant medications, which were coded using WHO-DD Version September 2017. A cycle where an ESA was administered concurrently was identified by comparing the start and stop dates of each administration of an ESA to the start of cycle and end of cycle. The occurrence of ESA administration was at least 1 cycle with an ESA administration during the treatment period. For the treatment period, the total number of ESA administrations was the number of cycles with ESA administrations.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Platelet Transfusion in Part 2	Within a cycle, a platelet transfusion event was defined as either 1) an actual platelet transfusion, or 2) eligible for platelet transfusion (defined as a platelet count =10 × 10^9/L). The occurrence of platelet transfusions was defined as at least 1 cycle with platelet transfusion during the treatment period. For the treatment period, the total number of platelet transfusions was the number of cycles with platelet transfusions.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Change From Baseline of Platelet Count at the End of Cycle 6, Part 2	Blood samples were collected for local clinical laboratory assessment of platelet count.	Baseline, Day 1, Day 3, Day 8, Day 10, and Day 15 of a 21-day cycle x 6
Secondary	Change From Baseline of Lymphocyte Count at the End of Cycle 6, Part 2	Blood samples were collected for local clinical laboratory assessment of lymphocyte count.	Baseline, Day 1, Day 3, Day 8, Day 10, and Day 15 of a 21-day cycle x 6
Secondary	Occurrence of Dose Reduction in Part 2	Dose reductions were not permitted for trilaciclib, per study protocol. Dose reductions for E/P were derived from changes in the protocol-specified dose on the dosing page and corresponded to the reductions for toxicity specified in the protocol. No more than 2 dose reductions of E/P in total were allowed for any participant. Simultaneous reductions in the doses of E/P were counted as 1 dose reduction. For the treatment period, the total number of dose reductions was the number of cycles where there was at least 1 dose reduction.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Infectious SAEs in Part 2	SAEs were defined as any untoward medical occurrence that at any dose resulted in death, was life threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity or was a congenital anomaly/birth defect. An infectious SAE was a serious event in the MedDRA system organ class "infections and infestations" and a preferred term of anal abscess, bacteraemia, bronchitis, candida infection, chronic sinusitis, conjunctivitis, infection, influenza, nasopharyngitis, oral candidiasis, oral herpes, pharyngitis streptococcal, pneumonia, pneumonia bacterial, respiratory tract infection, sepsis, skin infection, upper respiratory tract infection, urinary tract infection, urosepsis or viral upper respiratory tract infection.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of Pulmonary Infection SAE in Part 2	SAEs were defined as any untoward medical occurrence that at any dose resulted in death, was life threatening, requires inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity or was a congenital anomaly/birth defect. A pulmonary infection SAE was a serious event in the MedDRA system organ class "infections and infestations" and a preferred term of bronchitis, influenza, pneumonia, pneumonia bacterial, respiratory tract infection, upper respiratory tract infection or viral upper respiratory tract infection.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Occurrence of IV Antibiotic Administration in Part 2	Intravenous antibiotic administration was collected with concomitant medications, which were coded using WHO-DD Version September 2017. A cycle where IV antibiotic was administered concurrently was identified by comparing the start and stop dates of each administration of IV antibiotic to the start of cycle and end of cycle. The occurrence of IV antibiotic administration was defined as at least 1 cycle with IV antibiotic administration during the treatment period. For the treatment period, the total number of IV antibiotic administrations was the number of cycles with IV antibiotic administrations.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Time to First MAHE in Part 2	MAHE was a composite endpoint incorporating the measurement of several clinically meaningful aspects of myelopreservation into a single endpoint. The individual components for MAHE were hospitalization for a hematologic event, febrile neutropenia, death related to treatment, dose delay/reduction due to ANC or platelet counts, prolonged severe neutropenia (duration >5 days), RBC transfusion (actual or eligible) and platelet transfusion (actual or eligible). Time to first occurrence of a MAHE event was defined as the first time to observe an interested event among all the components, starting from the first dose date of study drug administration.	From randomization to the end of the treatment period (a minimum of 51 days up to a maximum of 379 days)
Secondary	Best Overall Tumor Response Based on Assessments in Part 2	Tumor response was assessed by CT or MRI. Overall visit response by RECIST v1.1 was derived programmatically using data from TLs, NTLs, & new lesions. Tumor response data were used to determine each participant's time point response & BOR. CR was disappearance of all TLs, any pathological lymph nodes selected as TLs must have reduced in short axis to <10 mm. PR was at least a 30% decrease from baseline in the sum of diameters of TLs, as long as criteria for PD were not met. PD was a =20% increase in the smallest sum of diameters of TLs since treatment started (including baseline) and an absolute increase of =5 mm. SD was neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD.	Baseline, end of every two 21-day cycles, up until disease progression to a maximum of the time at least 70% OS events observed (a maximum of 4 years)
Secondary	Best Overall Tumor Response Based on BICR Assessments in Part 2	Tumor response was assessed by CT or MRI. Overall visit response by RECIST v1.1 was determined by BICR. Tumor response data were used to determine each participant's time point response & BOR. CR was disappearance of all TLs, any pathological lymph nodes selected as TLs must have reduced in short axis to <10 mm. PR was at least a 30% decrease from baseline in the sum of diameters of TLs, as long as criteria for PD were not met. PD was a =20% increase in the smallest sum of diameters of TLs since treatment started (including baseline) and an absolute increase of =5 mm. SD was neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD.	Baseline, end of every two 21-day cycles, up until disease progression to a maximum of the time at least 70% OS events observed (a maximum of 4 years)
Secondary	PFS Based on Assessments in Part 2	Tumor response was assessed by CT or MRI. PFS was defined as the time (months) from date of first dose date of study drug for participants in Part 1 until date of documented disease progression or death due to any cause, whichever occurred first. More specifically, PFS was determined using all the assessment data up until the last evaluable visit prior to or on the date of i) disease progression as defined by RECIST 1.1 or by clinical criteria as determined by the investigator; or ii) withdrawal of consent; or iii) receiving subsequent anticancer therapy, whichever was earlier. For PFS determined using response data derived programmatically, either clinical progression or progression by RECIST (whichever came first) was considered. Median and inter-quartile range of PFS were calculated using the Kaplan-Meier method.	Baseline, end of every two 21-day cycles, up until disease progression to a maximum of the time at least 70% OS events observed (a maximum of 4 years)
Secondary	OS in Part 2	OS was calculated as the time (months) from date of first dose of study drug for participants in Part 2 to the date of death due to any cause. Participants who did not die during the study were censored at the date last known to be alive. Participants lacking data beyond the day of first dose of study drug had their survival time censored at day of first dose of study drug. OS was not censored if a participant received other anti-tumor treatments after the study drugs. Median and inter-quartile range of OS were calculated using the Kaplan-Meier method.	Baseline up until death or a maximum of the time at least 70% OS events observed (a maximum of 4 years)