Rapalog Pharmacology (RAP PAC) Study

The objective of RAP PAC is to identify safe and effective weekly dose(s) for the mTOR inhibitors sirolimus and everolimus that intervene on the underlying fundamental biology of aging. Participants who are 55-89 years old that are free of overt chronic diseases will be assigned to either 6 weeks of sirolimus or everolimus (5 mg, 10 mg, or 15 mg once per week). The investigators will complete the everolimus arm first and then subsequently complete the sirolimus arm of the study. Total time on study would be up to 17 weeks to complete baseline and follow up visits.