Shares in US biotechnology group, Antigenics, closed up almost 12% at $5.68 after a bout of heavy trading on October 10, following positive survival data from a Phase III clinical trial of the group’s cancer vaccine Oncophage.

Preliminary data from the study indicate that Oncophage, a personalised cancer therapy that uses malignant tumour tissue to prompt the patient's own immune system into attacking the cancer, extended the survival of advanced skin cancer patients by about eight months versus standard therapies.

But Antigenics cautioned that the results have yet to achieve statistical significance as, overall, survival was not found to be greater in the 322 patients taking part in the trial. The survival benefit was observed in a previously-defined group of subjects with the least-advanced severity of melanoma. This subset lived 20.9 months when treated with Oncophage compared to 12.8 months for those receiving standard therapy.

Although statistical significance has yet to be reached, the results are strong enough for the company to shell out $12-$15 million on a second Phase III study, which is now planned for the first half of 2006, evaluating Oncophage in this responsive group, the company said during a conference call.

This positive news, however shaky, may represent a tenuous lifeline for the firm, which has been through turbulent times of late. After a pretty poor performance over the past year, its shares have lost around half their value since the beginning of 2005, having exchanged hands for as much as $15 in 2003.