LY2603618 is a selective inhibitor of the deoxyribonucleic acid (DNA) damage checkpoint
kinase 1 (CHK1). It was being developed as a chemotherapeutic-enhancing agent in the
treatment of cancer. Phase 1 studies have shown the feasibility of combining LY2603618 with
either gemcitabine or pemetrexed. The objective of this study was to find the dose of
LY2603618 that can be safely combined with standard doses of pemetrexed and cisplatin and to
test if this triplet offered a significant improvement in progression-free survival (PFS) in
participants with Stage IV nonsquamous non-small cell lung cancer (NSCLC) in the first-line
of palliative treatment.