Aim 4. Subgroup analysis, population pharmacokinetics, and average bioequivalence Aim 4 is an exploratory aim in which we will (A) address the concern that bioequivalence in the "general" patient population will not translate to special subgroups such as high risk transplant recipients as characterized by genotype, race, age, gender, sensitization (repeat transplant or cytotoxic PRA >35% or calculated PRA >50%), presence of concomitant steroids, presence of diabetes. and (B) test alternative bioequivalence metrics that have been proposed for the analysis for immunosuppressant generics such as narrower acceptance intervals, average bioequivalence was well as population pharmacokinetics.