Development of topical formulations for delivery of next generation mTOR inhibito

DESCRIPTION (provided by applicant): We discovered that the inducible keratins 6a and 6b, mutations in which can result in the skin and nail disorder pachyonychia congenita (PC), contain regulatory motifs in their 5'-untranslated regions that make them susceptible to mTOR inhibitors, including rapamycin. Using RNA profiling and immunohistochemistry of foot sole biopsies taken from PC lesions or adjacent unaffected skin, we found evidence to support that mTOR signaling in PC lesions is activated as indicatedby hyperphosphorylated ribosomal protein S6. Based on the preclinical data, we completed a small off- label study of orally-administered Rapamune(R) in three PC patients in which improvement of PC symptoms was observed, with dramatic reduction of painfulneurovascular structures. However, the study was prematurely terminated due to the adverse events associated with systemic oral rapamycin administration. A recent off-label study with topical rapamycin led to marked improvement of PC symptoms, includi