Trilaciclib is a first-in-class myelopreservation therapy designed to improve outcomes of patients who receive chemotherapy by preserving hematopoietic stem and progenitor cell (HSPC) and immune system function. Trilaciclib is a short-acting intravenous CDK4/6 inhibitor administered prior to chemotherapy.

Trilaciclib is being evaluated in four randomized Phase 2 clinical trials. G1 has reported positive results from three of these trials in 2018. Two trials showed myelopreservation benefits in newly diagnosed, treatment-naive SCLC patients. In the first trial, trilaciclib was administered in combination with a chemotherapy regimen of etoposide and carboplatin (NCT02499770); topline data were released in March and additional data were reported at the European Society of Medical Oncology 2018 Congress. In the second trial, trilaciclib was administered in combination with the same chemotherapy regimen and the checkpoint inhibitor Tecentriq® (atezolizumab) (NCT03041311); topline data were reported in November. Results from a trial in combination with chemotherapy in metastatic triple-negative breast cancer (NCT02978716) showing enhanced progression-free survival and multi-lineage myelopreservation benefits were presented at the 2018 San Antonio Breast Cancer Symposium. The company plans to release topline data from a trial in combination with chemotherapy in previously treated SCLC (NCT02514447) by the end of 2018.

Data from a Phase 1 trial in healthy volunteers were presented at the American Society of Clinical Oncology 2015 Annual Meeting and published in Science Translational Medicine. Trilacicilib has been extensively studied in animals; these preclinical data have been presented at several scientific meetings and published in Molecular Cancer Therapeutics, Science Translational Medicine and Cancer Discovery.