Cyclosporin as microemulsion—is it a new drug?

Cyclosporin is a difficult drug to use; however, we are delighted to have it. Without any doubt, cyclosporin has dramatically improved long-term graft survival in renal transplant patients and opened the possibility of successful transplantation of vital organs such as the heart and the liver. Nevertheless, despite major advances there are significant drawbacks, and a number of practical problems persist. For instance, 10 years after renal transplantation roughly one-half of the patients have lost their grafts, either as a result of acute rejection episodes or as a result of what is called 'chronic rejection' but might perhaps be better designated 'chronic graft failure'. With this in mind, a debate continues on key issues such as: 'What is the ideal dose?', 'What is the best way to monitor this drug?', 'Are measurements of trough levels adequate?' and with regard to overimmunosuppression with the inherent risk of nephrotoxicity 'What is the magnitude of the risk?'.