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G1T38, a CDK 4/6 Inhibitor, in Combination With Osimertinib in EGFR-Mutant Non-Small Cell Lung Cancer

Phase 1
Completed
Conditions
Carcinoma, Non-Small-Cell Lung
Lung Cancer
Non-small Cell Lung Cancer
Interventions
Registration Number
NCT03455829
Lead Sponsor
G1 Therapeutics, Inc.
Brief Summary

This was a study to investigate the potential clinical benefit of G1T38 as an oral therapy in combination with osimertinib in patients with EGFR mutation-positive metastatic non-small cell lung cancer.

The study was an open-label design, planned to consist of 2 parts: a safety, pharmacokinetic, and dose-finding portion (Part 1), and a randomized portion (Part 2). Both parts were to include 3 study phases: Screening Phase, Treatment Phase, and Survival Follow-up Phase. The Treatment Phase began on the day of first dose with study treatment and completes at the Post-Treatment Visit. Approximately, 144 patients were planned to be enrolled in the study.

Detailed Description

Part 2, the Phase 2 part of the study, was not conducted due to changes in corporate strategy. There were no safety signals identified in Phase 1/Part 1 that would have precluded the conduct of Part 2. As a result, 30 out of the planned 144 patients were enrolled.

All tumor assessments were conducted by the Investigators or site radiologist. In order to reduce the burden to the patients, data of overall survival (OS) were no longer required (since 29 January 2020). No OS analysis was conducted for Part 1 due to limited data in Part 1.

PK data for Cohorts 4 (150 BID) and 5 (200 BID) were not analyzed as they were deemed unnecessary, as the PK data from Cohorts 1-3 were sufficient to achieve the secondary study objective of assessing the effect of osimertinib on PK parameters of G1T38.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
30
Inclusion Criteria
  • Confirmed EGFR mutation for non-small cell lung cancer associated with EGFR TKI sensitivity
  • For Part 2, EGFR T790M mutation-positive tumor status
  • Left ventricular ejection fraction (LVEF) ≥ institution's lower limit of the reference range
  • For Part 1, evaluable or measurable disease as defined by RECIST, Version 1.1
  • For Part 2, measurable disease as defined by RECIST, Version 1.1
  • ECOG performance status 0 to 1
  • Adequate organ function
Exclusion Criteria
  • Prior treatment with EGFR TKI within 9 days of first study dose
  • For Part 1, prior treatment with more than 2 prior lines of chemotherapy for advanced NSCLC
  • For Part 2, prior treatment with osimertinib or other T790M active EGFR TKI
  • For Part 2, prior chemotherapy for advanced NSCLC
  • Active uncontrolled/symptomatic CNS metastases, carcinomatous meningitis, or leptomeningeal disease
  • Investigational drug within 3 months or 5 half-lives, whichever is longer, of first study dose
  • Concurrent radiotherapy, radiotherapy within 28 days of first study dose, previous radiotherapy to the target lesion sites, or prior radiotherapy to > 25% of bone marrow
  • Prior hematopoietic stem cell or bone marrow transplantation

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Part 1: Cohort 1 G1T38 + OsimertinibG1T38Patients will receive a single oral dose of G1T38 on Cycle 1 Day -16 and on Cycle 1 Day -2. Patients will receive oral osimertinib 80 mg beginning Cycle 1 Days -14. Patients will begin G1T38 once-daily dosing on Cycle 1 Day 1 (in combination with osimertinib 80 mg).
Part 1: Cohort 3 G1T38 + OsimertinibG1T38Patients will receive a single oral dose of G1T38 on Cycle 1 Day -16 and on Cycle 1 Day -2. Patients will receive oral osimertinib 80 mg beginning Cycle 1 Days -14. Patients will begin G1T38 once-daily dosing on Cycle 1 Day 1 (in combination with osimertinib 80 mg).
Part 1: Cohort 3 G1T38 + OsimertinibOsimertinibPatients will receive a single oral dose of G1T38 on Cycle 1 Day -16 and on Cycle 1 Day -2. Patients will receive oral osimertinib 80 mg beginning Cycle 1 Days -14. Patients will begin G1T38 once-daily dosing on Cycle 1 Day 1 (in combination with osimertinib 80 mg).
Part 1: Cohort 4 G1T38 + OsimertinibG1T38Patients will receive a single oral dose of G1T38 on Cycle 1 Day -16 and on Cycle 1 Day -2. Patients will receive oral osimertinib 80 mg beginning Cycle 1 Days -14. Patients will begin G1T38 once-daily dosing on Cycle 1 Day 1 (in combination with osimertinib 80 mg).
Part 1: Cohort 4 G1T38 + OsimertinibOsimertinibPatients will receive a single oral dose of G1T38 on Cycle 1 Day -16 and on Cycle 1 Day -2. Patients will receive oral osimertinib 80 mg beginning Cycle 1 Days -14. Patients will begin G1T38 once-daily dosing on Cycle 1 Day 1 (in combination with osimertinib 80 mg).
Part 1: Cohort 5 G1T38 + OsimertinibG1T38Patients will receive a single oral dose of G1T38 on Cycle 1 Day -16 and on Cycle 1 Day -2. Patients will receive oral osimertinib 80 mg beginning Cycle 1 Days -14. Patients will begin G1T38 once-daily dosing on Cycle 1 Day 1 (in combination with osimertinib 80 mg).
Part 1: Cohort 2 G1T38 + OsimertinibG1T38Patients will receive a single oral dose of G1T38 on Cycle 1 Day -16 and on Cycle 1 Day -2. Patients will receive oral osimertinib 80 mg beginning Cycle 1 Days -14. Patients will begin G1T38 once-daily dosing on Cycle 1 Day 1 (in combination with osimertinib 80 mg).
Part 1: Cohort 2 G1T38 + OsimertinibOsimertinibPatients will receive a single oral dose of G1T38 on Cycle 1 Day -16 and on Cycle 1 Day -2. Patients will receive oral osimertinib 80 mg beginning Cycle 1 Days -14. Patients will begin G1T38 once-daily dosing on Cycle 1 Day 1 (in combination with osimertinib 80 mg).
Part 1: Cohort 1 G1T38 + OsimertinibOsimertinibPatients will receive a single oral dose of G1T38 on Cycle 1 Day -16 and on Cycle 1 Day -2. Patients will receive oral osimertinib 80 mg beginning Cycle 1 Days -14. Patients will begin G1T38 once-daily dosing on Cycle 1 Day 1 (in combination with osimertinib 80 mg).
Part 1: Cohort 5 G1T38 + OsimertinibOsimertinibPatients will receive a single oral dose of G1T38 on Cycle 1 Day -16 and on Cycle 1 Day -2. Patients will receive oral osimertinib 80 mg beginning Cycle 1 Days -14. Patients will begin G1T38 once-daily dosing on Cycle 1 Day 1 (in combination with osimertinib 80 mg).
Primary Outcome Measures
NameTimeMethod
Dose Limiting ToxicityCycle 1 Day -16 to Cycle 1 Day 28

The percentage of patients experiencing DLTs in Part 1 of the study in each cohort, including:

* Grade 4 neutropenia

* ≥ Grade 3 neutropenic infection/febrile neutropenia

* Grade 4 thrombocytopenia

* ≥ Grade 3 thrombocytopenia with bleeding

* ≥ Grade 3 nonhematologic toxicity (additional criteria for nausea, vomiting, diarrhea, or fatigue: lasting \> 5 days with maximal medical management)

* Liver function test abnormalities meeting Hy's Law criteria (aspartate aminotransferase \[AST\] or alanine aminotransferase \[ALT\] ≥ 3 × upper limit of normal \[ULN\] and total bilirubin ≥ 2 × ULN).

Secondary Outcome Measures
NameTimeMethod
Progression Free Survival (PFS)36 months

Median time (months) and 95% CI from date of first dose of study drug/randomization until date of documented disease progression or death due to any cause.

Response Evaluation Criteria in Solid Tumors (RECIST), Version 1.1 guidelines for tumor assessments were used to determine progression. Progressive Disease (PD) was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this includes the baseline sum if that is the smallest on study). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. (Note: the appearance of one or more new lesions is also considered progression).

Best Overall Tumor Response21 months

The percentage of patients who fall into each category of Best overall response (BOR) as defined by Response Evaluation Criteria in Solid Tumors (RECIST), Version 1.1 guidelines.

Complete Response (CR): Disappearance of all target lesions. Partial Response (PR): At least a 30% decrease in the sum of diameters of target lesions.

Progressive Disease (PD): At least a 20% increase in the sum of diameters of target lesions.

Stable Disease (SD): Neither sufficient shrinkage to qualify for PR nor sufficient increase to qualify for PD.

When no imaging/measurement is done, the patient is not evaluable (NE); and if only a subset of lesion measurements are made, usually the case is also considered NE.

Pharmacokinetics of G1T38 and Metabolite G1T30: Maximum Plasma Concentration (Cmax)Part 1, Cycle 1 Day -16 to Day -2.

The observed peak plasma concentration determined from the plasma concentration versus time data.

Pharmacokinetics of G1T38 and Metabolite G1T30: Area Under Curve - Plasma Concentration (AUC) InfinityPart 1, Cycle 1 Day -16 to Day -2.

Area under the concentration-time curve from time zero extrapolated to infinity using the linear-up log-down trapezoidal rule.

Pharmacokinetics of G1T38 and Metabolite G1T30: Plasma: Terminal Half Life (T1/2)Part 1, Cycle 1 Day -16 to Day -2.

Terminal half-life, defined as 0.693 divided by the terminal phase rate constant by λz , determined by linear regression of at least 3 points on the terminal phase of the log-linear plasma concentration-time curve.

Pharmacokinetics of G1T38: Plasma - Volume of DistributionPart 1, Cycle 1 Day -16 to Day -2.

Volume of distribution in the terminal elimination phase, calculated as:

Vz/F = (CL/F)/λz

Trial Locations

Locations (8)

St Joseph Heritage Healthcare

🇺🇸

Santa Rosa, California, United States

Virginia Cancer Specialists

🇺🇸

Fairfax, Virginia, United States

Beverly Hills Cancer Center

🇺🇸

Beverly Hills, California, United States

UCLA Medical Center, Division of Hematology/Oncology/Clinical Research Unit

🇺🇸

Santa Monica, California, United States

Sylvester Comprehensive Cancer Center/University of Miami Miller School of Medicine Fox Building, Suite 200 G

🇺🇸

Miami, Florida, United States

Mofitt Cancer Center

🇺🇸

Tampa, Florida, United States

Univ. of Michigan Hospitals

🇺🇸

Ann Arbor, Michigan, United States

Froedtert Hospital & the Medical College of Wisconsin

🇺🇸

Milwaukee, Wisconsin, United States

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