Effectiveness and Cost-effectiveness of a Pre-emptive Genotyping Strategy in Patients Receiving Tacrolimus

This study is testing whether testing a person's genes before a kidney transplant can help doctors better tailor the dosing of tacrolimus — a medication taken after transplants to prevent the body from rejecting the new organ. **You may be eligible if...** - You are on the waiting list for a kidney transplant - You are willing and able to participate and be followed up for most of the study - You have never had genetic testing for the CYP3A5 gene (which affects how your body processes tacrolimus) **You may NOT be eligible if...** - You have a known allergy to tacrolimus - You have previously had a kidney, heart, or liver transplant - You have a medical or surgical condition that significantly affects how your body absorbs or processes medications - You have any other condition that prevents safe participation Talk to your doctor to see if this trial is right for you.