Generic Drugs – Decreasing Costs and Room for Increased Number of Kidney Transplantations

Kidney transplantation is the best treatment option in comparison to dialysis, although patients are obliged to receive life-long medical treatment with immunosuppressive drugs (ISDs) for prevention of the graft rejection. Such immunosuppressive treatment may be costly and associated with multiple adverse effects. Since costs are viewed as one of the major constraints for the increasing number of transplantation, the use of generic ISDs may decrease the overall cost of transplantation and raise the possibility for its further development.

An ideal ISD should have the security margin between toxic and therapeutic dose, and prevent development of acute or chronic rejection of the transplanted kidney. This is particularly important for drugs with a "narrow therapeutical index" (NTI), where small differences in dose or concentration lead to dose and concentration-dependent, serious therapeutic failures and/or adverse drug reactions. The NTI generic drug is approved if within 90%-112% of the area under the curve of the original product the pharmacokinetics fulfills the strict criteria of pharmaceutical equivalence and bioequivalence. Every generic has to be proven to be bioequivalent to the innovator product, and not to other generic products because of the possible generic "drift". Thus, the generic ISDs may be economically attractive, but theoretically, they may pose a risk to transplant patients. Such risks may be reduced if a long-term clinical studies showing cost-effectiveness of generic ISDs in de novo and prevalent transplant patients for every new generic ISD are performed.

In conclusion, the increased number of solid organ transplantation goes in line with the increased health care expenditure for ISDs. The generic immunosuppressants could be a possible solution if safely substituted for innovator products or other generic drug of choice. The substantial cost reduction needs to be redirected into organ donation initiatives so that more patients can benefit from the further increase in transplantation.