Rapamycin whole blood levels after treatment with topical and IP rapamycin. A) Whole blood rapamycin levels from tumor bearing animals from indicated treatment groups. Rapamycin levels were measured 24 hours after the final dose of rapamycin. B) Whole blood rapamycin levels were measured in cohorts of control mice with no tumors. As indicated, levels were measured 24 hours after either one or three doses of topical rapamycin. In some groups, Elizabethan collars or bandages were used to prevent ingestion of rapamycin ointment. All animals had rapamycin levels >3 ng/ml. The slightly higher levels in the Elizabethan collar group suggests that ingestion is not a major issue. The lower levels in the bandage groups suggests that the bandage polymer can affect drug absorption. C) Whole blood rapamycin levels were also measured 48 hours after the final dose in tumor bearing animals. D) In three of the control, non-tumor bearing groups, rapamycin levels were measured at 48 hours following their final treatment to compare to tumor bearing animals.
Rauktys et al. BMC Dermatology 2008 8:1 doi:10.1186/1471-5945-8-1