G1 Therapeutics presents data from Phase 1b/2a trial of lerociclib at SABCS
G1 Therapeutics reported additional data from the Phase 1b/2a clinical trial investigating its oral CDK4/6 inhibitor lerociclib in combination with fulvestrant for the treatment of estrogen receptor-positive, HER2-negative breast cancer. Updated findings presented during a poster session at the 2019 San Antonio Breast Cancer Symposium, or SABCS, showed lerociclib, dosed without a drug holiday, has a differentiated safety and tolerability profile than observed in clinical trials with currently marketed CDK4/6 inhibitors. Preliminary efficacy findings were consistent with other CDK4/6 inhibitors used in combination with fulvestrant. The Phase 1b/2a trial is designed to evaluate the safety, tolerability and efficacy of lerociclib administered continuously in combination with fulvestrant as a treatment for ER+, HER2- breast cancer and identify the dose and schedule for future trials of lerociclib. Further investigation is ongoing, with longer-duration efficacy data required to determine the dose for future study in a Phase 3 clinical trial. The company expects to share an update in 2020.