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

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