Safety considerations of mammalian target of rapamycin inhibitors in tuberous sclerosis complex and renal transplantation

Rapamycin-related mTOR inhibitors (rapalogs) possess immunosuppressive and antiproliferative properties. Their mechanism of action makes them attractive therapies for several disease states but also potentiates adverse effects associated with these drugs. The oral mTOR inhibitor everolimus was recently approved for the treatment of tuberous sclerosis complex (TSC)-associated renal angiomyolipoma. As clinical use of rapalogs for the treatment of TSC increases, nephrologists and urologists who treat both children and adults with renal masses, as well as internists and geneticists with an interest in renal disease, should be aware of their safety profiles. This review presents the clinical experience of rapamycin-related mTOR inhibitors in patients with TSC and summarizes their toxicity profiles in renal transplant and TSC populations. Increased usage of rapalogs in a variety of patient populations demands vigilant monitoring of their safety profiles and rigorous differentiation between disease-specific and drug-specific toxicities.