ABSTRACT

Gene therapy can be considered a method of drug delivery. Gene therapy takes advantage of the host organism's gene transcription/translation machinery to locally produce bioactive substances. Gene therapy has been applied to retinal degeneration caused by dominant mutations such as those in the rhodopsin gene. Successful application of ocular gene therapy has been demonstrated in animal diseases or animal models of human disease. The most encouraging results in the field of ocular gene therapy involve treatment of genetically inherited retinal degenerations occurring in various animal species. Various animal models have been used to test gene therapy applications. One significant advantage of gene therapy delivery of pharmacologic agents is that therapeutic levels are maintained without the need for reinjection or implantation devices. Development of gene therapy as a viable, clinically successful methodology will require demonstration of proof-of-principle in a clinical trial. Initiation of a human clinical trial involving ocular gene therapy should be done cautiously—especially because ocular disease is rarely lethal.