noun. A purine analog, C₅H₄N₄S, that acts as an antimetabolite by interfering with purine synthesis, used primarily in the treatment of acute leukemia.

noun. A particular oral drug used in the treatment of cancer.

noun. a drug (trade name Purinethol) that interferes with the metabolism of purine and is used to treat acute lymphocytic leukemia

"The next regimen they would try would be a combination of all four drugs: vincristine, amethopterin, mercaptopurine, and prednisone."

antimetabolite  immune suppressant drug  immunosuppressant  immunosuppressive  immunosuppressive drug  

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