LY2603618 is primarily used in the field of oncology as a checkpoint kinase 1 (CHK1) inhibitor. It is designed to enhance the efficacy of chemotherapy by targeting the DNA damage response pathway in cancer cells. By inhibiting CHK1, LY2603618 prevents cancer cells from repairing DNA damage induced by chemotherapy, leading to increased cell death. This compound is often studied in combination with other chemotherapeutic agents, particularly in the treatment of solid tumors, to improve therapeutic outcomes and overcome resistance to standard treatments. Its application is focused on improving the precision and effectiveness of cancer therapies, particularly in cases where traditional treatments have limited success.