( LONDON 12 July 2007 - Cancer drug dev...)Antisoma Announces Further Data From ASA404 Ovarian Cancer Trial,Health

LONDON, 12 July 2007 - Cancer drug developer Antisoma plc (LSE: ASM, US OTC: ATSMY) today announces new data from its phase II trial of ASA404 in recurrent, platinum-sensitive ovarian cancer. This trial compares patients receiving ASA404 plus chemotherapy (n=37) with patients receiving chemotherapy alone (n=38). The main findings are as follows:

* There was no advantage in median time to tumour progression in the ASA404 arm compared with the control arm * One-year survival rates were 74% for the ASA404 arm and 92% for the control arm. Since the majority of patients in both arms were alive after one year, median survival values have not been determined * Independently-determined response rates were consistent with those previously reported from investigator assessment and showed a higher response rate in the ASA404 arm * Addition of ASA404 to chemotherapy was generally well tolerated.

Based on these data, development in ovarian cancer will not be a priority.

Antisoma has been testing ASA404 in several cancer types and previously reported a 5-month increase in median survival when the drug was added to chemotherapy in non-small cell lung cancer.

Antisoma licensed ASA404 to Novartis in April 2007. Novartis plans to start enrolling patients into a phase III trial in non-small cell lung cancer early in 2008 and to explore the potential benefits of the compound in various other solid tumours.

Glyn Edwards, Antisoma's CEO said, "Our ovarian cancer trial has not produced positive results like those seen with ASA404 in lung cancer. More broadly, we're very pleased with the progress made by Novartis to date with ASA404 in lung cancer and look forward to working with them to fully evaluate the drug in other cancers."

Enquiries: Glyn Edwards, Chief Executive Officer Daniel Elger, Director of Communications +44 (0) 7909 915068 Antisoma plc

Mark Court/Lisa Baderoon/Rebecca Sky
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