Medication review: FK 506

Area of Science:

• Nephrology and Immunology
• Transplantation Medicine

Background:

• Current immunosuppressive therapies for renal transplantation face challenges with rejection rates and side effects.
• The novel immunosuppressant FK 506 (tacrolimus) is being evaluated as an alternative to standard treatments like cyclosporine (CyA).

Purpose of the Study:

• To compare the efficacy and safety of FK 506 with current standard immunosuppressive therapies in renal transplant recipients.
• To assess the impact of FK 506 on clinical rejection rates, allograft and patient survival, infection incidence, and the need for rescue therapies.

Main Methods:

• Clinical trial data from a single-site study comparing FK 506 with cyclosporine (CyA) in renal transplant patients.
• Evaluation of rejection rates, patient and allograft survival, infection incidence, and the requirement for additional immunosuppressive treatments (steroid boluses, steroid recycles, OKT 3).

Main Results:

• FK 506 demonstrated a slightly lower absolute rate of clinical rejection compared to standard therapies.
• Fewer steroid boluses, steroid recycles, and OKT 3 courses were required in the FK 506 group versus the CyA group.
• FK 506 did not significantly alter allograft or patient survival or the incidence of infection compared to CyA, but allows for potential reduction of azathioprine and prednisone.

Conclusions:

• FK 506 shows promise in reducing rejection and the need for rescue therapies in renal transplantation, with a potential to decrease reliance on other immunosuppressants.
• Further multi-center data is crucial to establish optimal dosing, understand side effect profiles, and define the long-term role of FK 506 in renal transplantation.
• The frequency and severity of FK 506 side effects will be critical factors in determining its long-term clinical utility for kidney transplant recipients.