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

G1 Therapeutics

Status and phase: Completed; Phase 2; Phase 1

Conditions: Non-small Cell Lung Cancer; Carcinoma, Non-Small-Cell Lung; Lung Cancer

Treatments: Drug: Osimertinib; Drug: G1T38

Study type: Interventional

Funder types: Industry

Identifiers

NCT03455829

G1T38-03

2017-004315-39 (EudraCT Number)

Details and patient eligibility

About

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.

Full 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.

Enrollment: 30 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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30 participants in 5 patient groups

Part 1: Cohort 1 G1T38 + Osimertinib

Experimental group

Description:

Patients 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).

Treatment:

Drug: G1T38

Drug: Osimertinib

Part 1: Cohort 2 G1T38 + Osimertinib

Experimental group

Description:

Patients 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).

Treatment:

Drug: G1T38

Drug: Osimertinib

Part 1: Cohort 3 G1T38 + Osimertinib

Experimental group

Description:

Patients 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).

Treatment:

Drug: G1T38

Drug: Osimertinib

Part 1: Cohort 4 G1T38 + Osimertinib

Experimental group

Description:

Patients 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).

Treatment:

Drug: G1T38

Drug: Osimertinib

Part 1: Cohort 5 G1T38 + Osimertinib

Experimental group

Description:

Patients 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).

Treatment:

Drug: G1T38

Drug: Osimertinib