Abstract
Introduction: Many rare diseases are caused by mutations in various genes, and therefore corrective gene therapy entitled with orphan drug status can be considered as a plausible therapeutic approach.
Areas covered: This is another article of the series dedicated to the orphan drug designation procedure in the European Union. The orphan drugs designated for diseases for which no medicine is authorised in the European Union are discussed. In this article, most of them are dedicated to retinitis pigmentosa and to urea cycle disorders.
Expert opinion: In rare diseases such as retinitis pigmentosa in which many gene mutations can be causative, therapies able to address the common pathogenesis of various disease subsets can be of particular interest for pharmaceutical companies, whereas the gene therapies are not less attractive but more specific and might be considered as personalised medicine approaches. In urea cycle disorders hepatic precursor transplantation or recombinant enzymes might hold good therapeutic potential.
Declaration of interest
The author states no conflict of interest and has received no payment in preparation of this manuscript.