An anticancer drug that belongs to a family of drugs called antimetabolites. Or A polyglutamatable folate antagonist analogue of methotrexate with antineoplastic activity. Edatrexate inhibits dihydrofolate reductase, thereby increasing cellular levels of polyglutamates, inhibiting thymidylate synthase and glycinamide ribonucleotide formyl transferase, impairing synthesis of purine nucleotides and amino acids, and resulting in tumor cell death. Edatrexate may overcome tumor resistance to methotrexate, which loses its activity after it is polyglutamated.