UK gene therapy group, Oxford BioMedica, has reported encouraging preliminary results from an ongoing Phase II clinical study of its therapeutic cancer vaccine TroVax in renal cell carcinoma, showing not only that the product has been safe and well tolerated, but that it also induces a strong anti-tumour immune response. In addition, no serious side effects have been observed, which is consistent with the safety profile of TroVax across all trials, the firm noted.

The open-label study is designed to assess TroVax (anti-5T4 antibody) in combination with interleukin-2 therapy, a US Food and Drug Administration-approved treatment for kidney cancer, to determine whether the vaccine generates an immune response to cancer cells. Secondary efficacy endpoints include tumour response, time to disease progression and overall survival.

To date, seven participants of a planned 25 have been recruited in the study, with five having reached the point for preliminary analysis of immune response. All demonstrated good anti-tumour antibody responses against the 5T4 tumour antigen, with levels at the top end of the range reported from the Phase II trials with TroVax in colorectal cancer.

Commenting on the results, Oxford BioMedica’s chief executive, Professor Alan Kingsman, stated: “It is very encouraging that the results with TroVax in renal cell carcinoma are consistent with our data set in colorectal cancer. Renal cell carcinoma is an aggressive disease with an unmet need for effective treatments. The high levels of 5T4 in renal cancer and the paucity of treatment options make this an ideal setting for further development of TroVax.”

However, investors seemed relatively unmoved by the news, as shares of the firm, trading on the London Stock Exchange, closed down just under 1.2% at 42 pence.

Wyeth signed an agreement with BioMedica back in January 2001, giving the former an option to acquire exclusive development and worldwide marketing rights for TroVax in all cancer indications [[05/03/03e]], in a deal worth up to $24 million to Oxford BioMedica. Wyeth is also developing a humanised version of the antibody TroVax is based on, according to Oxford BioMedica’s latest financial report.