Current Gene Therapy - Volume 13, Issue 6, 2013

This introductory paper gathers general considerations on the biosafety of virus-derived vectors that are used in human gene therapy and/or vaccination. The importance to assess the potential risks for human health and the environment related to the use of genetically modified organisms (GMO) in this case genetically modified viral vectors is highlighted by several examples. This environmental risk assessment is Read More

Risk assessments of clinical applications involving genetically modified viral vectors are carried out according to general principles that are implemented in many national and regional legislations, e.g., in Directive 2001/18/EC of the European Union. Recent developments in vector design have a large impact on the concepts that underpin the risk assessments of viral vectors that are used in clinical trials. The use of (conditi Read More

The modified vaccinia virus Ankara (MVA) strain, which has been developed as a vaccine against smallpox, is since the nineties widely tested in clinical trials as recombinant vector for vaccination or gene therapy applications. Although MVA is renowned for its safety, several biosafety aspects need to be considered when performing the risk assessment of a recombinant MVA (rMVA). This paper presents the biosafety issues and Read More

Adenovirus vectors are the most commonly employed vector for cancer gene therapy. They are also used for gene therapy and as vaccines to express foreign antigens. Adenovirus vectors can be replication-defective; certain essential viral genes are deleted and replaced by a cassette that expresses a foreign therapeutic gene. Such vectors are used for gene therapy, as vaccines, and for cancer therapy. Replication-compet Read More

It is hoped that the use of gene transfer technology to treat both monogenetic and acquired diseases may soon become a common therapy option in medicine. For gene therapy to achieve this objective, any gene delivery method will have to meet several criteria, including ease of manufacturing, efficient gene transfer to target tissue, long-term gene expression to alleviate the disease, and most importantly safety i Read More

Lentiviral vectors are promising tools for the genetic modification of cells in biomedical research and gene therapy. Their use in recent clinical trials for the treatment of adrenoleukodystrophy, β-thalassemia, Wiskott-Aldrich- Syndrome and metachromatic leukodystrophy underlined their efficacy for therapies especially in case of hereditary diseases. In comparison to gammaretroviral LTR-driven vectors, which were employed in th Read More

Gene therapy has become a feasible and efficient strategy for the treatment of human genetic diseases. The main principle of a gene therapeutic regimen relies on the delivery of a corrected gene of interest in human cells. In about one fifth of the clinical trials, gamma-retroviral vectors are used as gene-transfer vehicle. However, previous successful gene therapy trials revealed gamma-retroviral vector-mediated severe adv Read More

The majority of humans have been infected with Herpes Simplex Virus Type 1 (HSV-1) and harbor its viral DNA in the latent form within neurons for lifetime. This, combined with the absence of serious adverse effects due to HSV-1 derived vectors in clinical trials so far, highlight the potential to use this virus to develop neuronal gene transfer vectors which are transparent to the host, allowing the effects of the transgene to act w Read More

The concept of using viruses as oncolytic agents is not a new one. In an effort to improve the applicability of viral anti-cancer agents various non-human viruses are being evaluated preclinically and clinically. The application of replication- competent non-human viruses poses new potential hazards, i.e. those associated with the possible adaptation of the therapeutic viruses to the human hosts. Therefore it is essential to wei Read More