cisplatin + erlotinib + pemetrexed

This is a combination regimen consisting of three drugs—cisplatin, erlotinib, and pemetrexed—used primarily in the treatment of certain cancers, most notably non-small cell lung cancer (NSCLC).

• Cisplatin is a platinum-based chemotherapeutic agent that forms DNA crosslinks and inhibits DNA synthesis and function, leading to apoptosis in rapidly dividing cells.
• Erlotinib is an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor that blocks EGFR signaling pathways involved in tumor cell proliferation and survival.
• Pemetrexed is an antifolate antineoplastic agent that disrupts folate-dependent metabolic processes essential for cell replication by inhibiting multiple enzymes involved in purine and pyrimidine synthesis.

This combination targets cancer cells through complementary mechanisms—DNA damage (cisplatin), inhibition of growth signaling (erlotinib), and disruption of nucleotide synthesis (pemetrexed)—and has been investigated or used as a first-line or subsequent therapy for advanced or metastatic NSCLC, particularly non-squamous subtypes.