New immunosuppressive drugs in dermatology (mycophenolate mofetil, tacrolimus): unapproved uses, dosages, or indications.

In the past two decades, many new small molecules with immunosuppressive properties have been discovered. These xenobiotic drugs have been particularly developed for clinical use in organ transplantation to prevent allograft rejection. During clinical investigation in transplantation, some of these substances have also been observed to provide therapeutic efficacy in inflammatory skin disorders. Subsequently, a large number of clinical trials have been performed in the field of immunomodulatory therapy in dermatologic disorders to evaluate the safety and efficacy of these new drugs. This chapter focuses on the mechanisms of action and the clinical experience in dermatology with mycophenolate mofetil (MMF) and tacrolimus.