Research report on Recombination between HIV and lentiviral vectors

The Committee on Genetic Modification (COGEM) recently commissioned a study to investigate whether new viruses could emerge as a result of gene therapies using lentiviral vectors. These vectors are related to the human immunodeficiency virus (HIV), which means there is a theoretical risk of genetic material being exchanged between the vector and the virus in people with HIV. This could lead to new variants of HIV.

Until now, this risk was considered to be very small, but there was a lack of experimental evidence. The study, carried out by the Amsterdam University Medical Centre (Amsterdam UMC), shows that no new viruses arise when using the most common lentiviral vector: the self-inactivating (SIN) lentiviral vector. However, when using non-self-inactivating lentiviral vectors, which are less safe, the exchange of genetic material has been observed. The emergence of new viruses cannot therefore be ruled out with these vectors.

The results of the study are important for the environmental risk assessment of clinical trials and laboratory experiments involving lentiviral vectors. The findings support COGEM’s previous advice that people with HIV can safely participate in clinical trials using SIN lentiviral vectors. For non-SIN lentiviral vectors, the risk to people with HIV remains relevant.