Safety consideration on the conversion of tacrolimus formulations

Tacrolimus is a powerful immunosuppresant and is characterized by narrow therapeutic window and considerable individual variability of pharmacokinetics features.Small changes in the tacrolimus dose or concentration in blood may lead to adverse effect even the failure of therapy.However,the required range、study population and test parameters of bioequivalence study are not suitable for narrow therapeutic index drug such as tacrolimus.Therefore,these generic tacrolimus formulations may not be therapeutic equivalent to progarf and the conversion to different tacrolimus formulations must be undertaken with caution.