Vical Initiates Leuvectin Gene Therapy Trial

Vical has begun Phase I/II clinical testing of its Leuvectin cancer gene therapy product at the Arizona Cancer Center in Tucson, USA. The trial is expected to enroll around 25 patients with advanced solid tumors or lymphomas.

Leuvectin comprises naked DNA which encodes interleukin-2 and is injected directly into tumors. It is hoped that Leuvectin will cause the transfected cells to produce IL-2 in the vicinity of the lesion and stimulate a host immune response to the neoplastic cells. IL-2 is a tried and tested therapy for renal cell carcinoma, and has been approved for this indication for several years. However, systemic administration of the agent can be associated with severe side effects, and this has limited its applicability in solid cancer treatment. Vical hopes that genetic delivery of IL-2 will enhance the therapeutic window of the treatment.

Vical's lead cancer gene therapy product, Allovectin-7, is now completing Phase I/II trials (Marketletter April 3). Like Leuvectin, the product is also intended for direct injection into tumor lesions of cancer patients and in this case contains a gene that encodes a mismatched transplantation antigen (HLA-B7) which is expressed on the surface of the cells and stimulates the immune system to mount a cytotoxic response.