Patent ID: 7781447

Claim:
A method of inhibiting a post-transplant lymphoproliferative disorder (PTLD) in a human patient at risk for developing the disorder due to transplantation of a tissue, the method comprising administering to the patient prior to transplantation of a tissue and in an amount sufficient to inhibit the disorder, a rapamycin derivative having the chemical structure wherein X is (H, H) or O; Y is (H, OH) or O; R 1 is independently selected from the group consisting of alkyl, thioalkyl, arylalkyl, hydroxyalkyl, dihydroxyalkyl, hydroxyalkylarylalkyl, dihydroxyalkylarylalkyl, alkoxyalkyl, acyloxyalkyl, aminoalkyl, alkylaminoalkyl, alkoxycarbonylaminoalkyl, acylaminoalkyl, arylsulfonamidoalkyl, allyl, dihydroxyalkylallyl, dioxolanylallyl, carbalkoxyalkyl, and (R 3 ) 3 Si; R 2 is selected from the group consisting of —H, alkyl, thioalkyl, arylalkyl, hydroxyalkyl, dihydroxyalkyl, hydroxyalkylarylalkyl, dihydroxyalkylarylalkyl, alkoxyalkyl, acyloxyalkyl, aminoalkyl, alkylaminoalkyl, alkoxycarbonylaminoalkyl, acylaminoalkyl, arylsulfonamidoalkyl, allyl, dihydroxyalkylallyl, dioxolanylallyl, carbalkoxyalkyl, and (R 3 ) 3 Si; each R 3 is independently selected from the group consisting of —H, methyl, ethyl, isopropyl, tert-butyl, and phenyl; and either R 4 is methyl or R 4 and R 1 together form a C 2-5 alkylene moiety, wherein the patient is in need of the tissue transplantation, thereby inhibiting development of a PTLD in the patient.