A 50-year-old male, Ram Lal is suffering from renal failure, underwent kidney transplantation. He was prescribed a nucleotide derivative following the organ transplantation. what is that drug?

Anti proliferative drugs (Cytotoxic immunosuppressants) -Ceain cytotoxic drugs used in cancer chemotherapy exhibit prominent immunosuppressant action, mainly by preventing the clonal expansion of T and B lymphocytes (see Fig. 63.1). Azathioprine - It is a purine antimetabolite which has more marked immunosuppressant than antitumor action. The basis for this difference is not clear but may be due to its selective uptake into immune cells and intracellular conversion to the active metabolite 6-mercaptopurine, which then undergoes fuher transformations to inhibit de novo purine synthesis and damage to DNA It selectively affects differentiation and function of T cells and inhibits cytolylic lymphocytes; cell-mediated immunity is primarily depressed. The most impoant application of azathioprine is the prevention of renal and other graft rejection, but it is less effective than cyclosporine; generally combined with it or used in patients developing cyclosporine toxicity. It has also been used in progressive rheumatoid ahritis , and other autoimmune diseases. ESSENTIALS of MEDICAL PHARMACOLOGY SIXTH EDITION -K. D TRIPATHI Page:844