cetuximab + pemetrexed

A combination therapy consisting of cetuximab, a chimeric monoclonal antibody targeting the epidermal growth factor receptor (EGFR), and pemetrexed, an antifolate chemotherapy agent that inhibits multiple folate-dependent enzymes. Cetuximab works by binding to the extracellular domain of EGFR, blocking signal transduction and causing receptor downregulation. Pemetrexed disrupts folate metabolism by inhibiting thymidylate synthase, dihydrofolate reductase, and glycinamide ribonucleotide formyltransferase, which are essential for DNA synthesis and cell replication. This combination has been studied primarily for the treatment of recurrent non-small cell lung cancer and head and neck squamous cell carcinoma.