CellCept is a tablet that contains mycophenolate mofetil, a medicine that helps stop the immune system from attacking a newly transplanted kidney. In this study, participants take the tablet by mouth to see how other drugs might change the way mycophenolate works in the body and how it affects the gut bacteria.

Mycophenolate mofetil Accord is another brand of the same medicine, mycophenolate mofetil, also taken as a tablet by mouth. It serves the same purpose as CellCept – to suppress the immune response after a kidney transplant – and is used in the trial to compare how different antimicrobial drugs may influence its behavior in the body and the gut microbiome.

Advagraf is a hard capsule that contains tacrolimus, a medication that also suppresses the immune system to protect a transplanted kidney from rejection. Participants swallow the capsule, and the study looks at how antimicrobial drugs might affect the amount of tacrolimus that reaches the bloodstream and its impact on gut bacteria.

PROGRAF is another brand of tacrolimus, provided as a capsule taken by mouth. Like Advagraf, it works to prevent the immune system from attacking the new kidney, and the trial uses it to examine whether other drugs change its absorption and its interaction with the gut microbiome.

Kidney transplantation – Kidney transplantation is the surgical placement of a healthy donor kidney into a person whose own kidneys no longer work adequately. After surgery, the transplanted organ begins to filter blood, producing urine and helping to regulate fluid and electrolytes. Over time, the new kidney can maintain normal kidney function, but the recipient’s immune system may gradually recognize it as foreign, leading to a slow decline in function if not controlled. The transplanted kidney can also be affected by injuries, infections, or chronic changes that reduce its filtering ability. Monitoring of kidney performance shows how the organ adapts and ages within the recipient’s body.