Corneal permeation studies of everolimus microemulsion.
OBJECTIVE
To prevent corneal-graft rejection, the topical application of an immunosuppressive drug is an alternative to the systemic application of immunosuppressive drugs or corticosteroids, which may have adverse side effects. The aim of this study was to determine the permeation rate of everolimus through freshly isolated pig cornea (ex vivo).


METHODS
A fluorescence polarization immunoassay with a commercially available assay system was used to quantify everolimus in the acceptor samples of the permeation tests.


RESULTS
Everolimus is a poorly soluble drug and was, therefore, incorporated in an eye-administrable microemulsion. The stability of this microemulsion containing 0.1% (1 mg/mL) of the drug was satisfying over a period of 12 months. A concentration of 8.64 ng/mL was already reached 30 min after administration of the microemulsion to the cornea.


CONCLUSIONS
This everolimus-containing microemulsion is a promising ocular formulation for preventing corneal-graft rejection.
Baspinar
Yuecel
Y
Institute of Pharmacy, Free University of Berlin, Berlin, Germany. baspinar@zedat.fu-berlin.de
Bertelmann
Eckart
E
Pleyer
Uwe
U
Buech
Guido
G
Siebenbrodt
Ingo
I
Borchert
Hans-Hubert
HH
D000818:Animals; D003315:Cornea / Q000187:drug effects* / Q000378:metabolism*; D016503:Drug Delivery Systems / Q000379:methods; D004355:Drug Stability; D004655:Emulsions; D000068338:Everolimus; D010539:Permeability / Q000187:drug effects; D020123:Sirolimus / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D013552:Swine
D004655:Emulsions; D000068338:Everolimus; D020123:Sirolimus