A class of medications known as purine antimetabolites works by imitating or blocking the actions of purine bases to obstruct the formation of nucleotides, which are the building blocks of DNA and RNA. These medications are frequently used in chemotherapy to target cancer cells that divide quickly. Below is a summary of several important purine antimetabolites: Sixth-generation purine (6-MP): This medication is a structural analogue of adenine, the purine base. 6-MP is transformed into active metabolites inside the cell, which block purine synthesis-related enzymes and ultimately interfere with the synthesis of DNA and RNA. 6-MP is used to treat different hematological malignancies as well as acute lymphoblastic leukemia (ALL). Azathioprine: The body converts the prodrug azathioprine to 6-MP. By interfering with purine synthesis and nucleic acid metabolism, it functions similarly to 6-MP. Azathioprine is used as an immunosuppressant to treat autoimmune conditions such as inflammatory bowel disease and rheumatoid arthritis, as well as to avoid organ rejection in transplant patients.Another analogue of the purine base guanine is thioguanine (6-TG). It is transformed into active metabolites that block purine synthesis-related enzymes, just like 6-MP. When resistance to other purine analogs develops, thioguanine is used to treat hematological malignancies, including ALL. Cladribine, often known as 2-CdA, is an artificial purine nucleoside analog that shares structural similarities with adenosine. Deoxycytidine kinase phosphorylates it, resulting in an active metabolite that prevents DNA synthesis and repair. Hairy cell leukemia is an uncommon kind of blood cancer that is treated with cladribine.Fludarabine: A fluorinated purine nucleoside analog, fludarabine blocks DNA synthesis by obstructing ribonucleotide reductase and DNA polymerase. It is used to treat non-Hodgkin lymphoma and chronic lymphocytic leukemia (CLL), sometimes in conjunction with other medications. Because these purine antimetabolites specifically target fast dividing cells, they have changed the treatment of cancer. They do, however, also carry the potential of adverse consequences, including gastrointestinal toxicity, immunosuppression, and myelosuppression. To balance the potential negative effects of these drugs with their therapeutic benefits, close observation and dose modifications are required.
