Glioma: new hopes from virotherapy
In Glasgow (UK) Herpes simplex viruses have been employed for experimental treatment of malignant glioma, a brain cancer of glial tissue. The injected virus has a gene deletion that restricts it to actively dividing cells such as cancers. This research is in the Phase II, i.e. the phase intended to determine the appropriate dose. The Herpes simplex virus used in a similar study in Martinsried (Germany) harbours two gene deletions that prevent it from reproducing in normal cells (Phase II, as well). In Calgary and Alberta (Canada), the virus employed is a Reovirus able to replicate only in cancer cells bearing the activated oncogene ras. Part of the researches in Canada are still in Phase I (the phase designed to determinate the safety) part are in the second phase.
Frequently virotherapy has been confused with gene therapy: the distinction is not banal or academic, since the two different procedures may be related to different risk degrees.
Virotherapy uses actively replicating viruses to kill specific types of cells. Gene Therapy employs crippled versions of viruses, such as Adenovirus, to introduce a new gene into cells. Both largely rely on Adenoviruses, but other species are employed as in the therapy of glioma.
BM&L members discussed the case of Jesse Gelsinger occurred in 1999 (see in CURRENT section).