Tacrolimus is the new name for the Japanese immunosuppressant drug FK5
06. It blocks interleukin 2 transcription thereby inhibiting the CD4 T
h-1 lymphocyte response to foreign antigens. It also selectively inhib
its cytokine secretion of IL3, IL4 and interferon-gamma. It is metabol
ised by the cytochrome P-450 enzyme system. The results of two trials
indicate that it is similar to cyclosporin in efficacy and toxicity.