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

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.

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.