G1 Therapeutics, Inc. is a commercial-stage biopharmaceutical company. The Company is focused on the development and commercialization of small molecule therapeutics for the treatment of patients with cancer. The Company's lead commercial product, COSELA (trilaciclib), is a therapy indicated to proactively help protect bone marrow (myeloprotection) from the damage of chemotherapy. Its product portfolio consists of Trilaciclib and Lerociclib, both of which are CDK4/6 inhibitors, and a Cyclin-dependent kinase 2 (CDK2) inhibitor. Trilaciclib is a novel therapy designed to transiently arrest cells that are dependent on CDK4/6 for proliferation, including hematopoietic stem and progenitor cells (HSPCs), in the G1 phase. Lerociclib is a differentiated clinical-stage oral CDK4/6 inhibitor being developed for use in combination with other targeted therapies in multiple oncology indications. COSELA is a short-acting intravenous CDK4/6 inhibitor. Its CDK2 is an internally discovered inhibitor.