Gene therapy is becoming a very promising and feasible medical intervention as the understanding of human diseases extends to their molecular levels. Since the first US Food and Drug Administration (FDA)-approved human gene therapy protocol was approved in 1990, over 300 human clinical trial protocols had been approved worldwide so far. Even though some of the domestic gene therapy clinical trials also proved promising and more are awaiting, it should be emphasized that many safety aspects as well as effectiveness aspects should be considered during the development process. Moreover, there seems to be less restricted guidelines from the National Control Authority (NCA) in initiating human clinical trials. This article is intended to suggest some basis and points to consider in the development and evaluation of gene therapy products including antisense oligonucleotides pharmaceuticals.