pemetrexed + lenalidomide

Pemetrexed + lenalidomide is an investigational combination therapy consisting of two small molecule drugs, pemetrexed and lenalidomide. Pemetrexed is a folate antimetabolite chemotherapy agent that inhibits multiple enzymes involved in folate metabolism and DNA synthesis, including thymidylate synthase, dihydrofolate reductase, and glycinamide ribonucleotide formyltransferase. Lenalidomide is an immunomodulatory drug (IMiD) that exerts anti-tumor effects through direct cytotoxicity, inhibition of angiogenesis, and modulation of the immune system by altering cytokine production and enhancing natural killer (NK) cell activity. The combination has been studied as salvage treatment for relapsed/refractory primary central nervous system lymphoma (PCNSL), showing promising efficacy with moderate toxicity in heavily pretreated patients[1][5][6].