A study on gene therapy, a new revolution and hopefor incurable cancers

Gene therapy is a medical field which focuses on the genetic modification of cells to produce atherapeutic effect or the treatment of disease by repairing or reconstructing defective geneticmaterial. The first attempt at modifying human DNA was performed in ۱۹۸۰, by Martin Cline, but thefirst successful nuclear gene transfer in humans, approved by the National Institutes of Health, wasperformed in May ۱۹۸۹. The first therapeutic use of gene transfer as well as the first direct insertionof human DNA into the nuclear genome was performed by French Anderson in a trial starting inSeptember ۱۹۹۰. It is thought to be able to cure many genetic disorders or treat them over time.In۱۹۸۹, the concept of human gene therapies has emerged with the first approved human gene therapytrial of Rosenberg et al. Gene therapies are considered as promising therapies applicable to a broadrange of diseases. The objective of this study was to review the descriptive data on gene therapyclinical trials conducted worldwide between ۱۹۸۹ and ۲۰۱۵, and to discuss potential success rates ofthese trials over time and anticipated market launch in the upcoming years. A publicly availabledatabase, ‘Gene Therapy Clinical Trials Worldwide’, was used to extract descriptive data on genetherapy clinical trials: (۱) number of trials per year between ۱۹۸۹ and ۲۰۱۵; (۲) countries; (۳) diseasestargeted by gene therapies; (۴) vectors used for gene delivery; (۵) trials status; (۶) phases ofdevelopment. Between ۱۹۸۹ and ۲۰۱۵, ۲,۳۳۵ gene therapy clinical trials have been completed, wereongoing or approved (but not started) worldwide. The number of clinical trials did not increase steadilyover time; it reached its highest peak in ۲۰۱۵ (۱۶۳ trials). Almost ۹۵% of the trials were in early phasesof development and ۷۲% were ongoing. The United States undertook ۶۷% of gene therapy clinicaltrials. The majority of gene therapies clinical trials identified targeted cancer diseases. The first genetherapy was approved in the European Union in ۲۰۱۲, after two decades of dashed expectations. Thisapproval boosted the investment in developing gene therapies. Regulators are creating a specific pathfor rapid access of those new therapies, providing hope for manufacturers, healthcare professionals,and patients.