Novartis AG Stops Lung Cancer Drug Trial of ASA404, Developed in Partnership with Antisoma PLC, Books $120 Million Charge

LONDON and CAMBRIDGE, MA--(Marketwire - November 11, 2010) - Antisoma plc (LSE: ASM; USOTC: ATSMY) announces that a scheduled interim analysis showed that the ATTRACT- 2 trial should stop as ASA404 was unlikely to provide any benefit as a second-line treatment for non-small cell lung cancer.

Glyn Edwards, CEO of Antisoma, said: "The findings from ATTRACT-2 mirror those from ATTRACT-1 and therefore come as no surprise. Our focus for some time has been on other programmes, most notably AS1413, which reports phase III data in the first half of next year."

Except for the historical information presented, certain matters discussed in this announcement are forward looking statements that are subject to a number of risks and uncertainties that could cause actual results to differ materially from results, performance or achievements expressed or implied by such statements. These risks and uncertainties may be associated with product discovery and development, including statements regarding the company's clinical development programmes, the expected timing of clinical trials and regulatory filings. Such statements are based on management's current expectations, but actual results may differ materially.

About the ATTRACT studies in non-small cell lung cancer (NSCLC) ATTRACT-2 was a pivotal study carried out by Novartis to evaluate ASA404 in previously treated, advanced NSCLC. Patients were randomised to receive either ASA404 plus docetaxel or a placebo plus docetaxel as a control. A separate study, ATTRACT-1, had investigated ASA404 as a first-line treatment for NSCLC.

About ASA404

ASA404 (vadimezan, formerly known as DMXAA and AS1404) is a small-molecule Tumour-Vascular Disrupting Agent (Tumour-VDA) which targets the blood vessels that nourish tumours. The drug was discovered by Professors Bruce Baguley and William Denny and their teams at the Auckland Cancer Society Research Centre, University of Auckland, New Zealand. It was in-licensed by Antisoma from Cancer Research Ventures Limited (now Cancer Research Technology), the development and commercialisation company of the Cancer Research Campaign (now Cancer Research UK), in 2001. Worldwide rights to the drug were licensed to Novartis AG in April 2007.

About Antisoma

Antisoma is a London Stock Exchange-listed biopharmaceutical company that develops novel products for the treatment of cancer. The Company has operations in the UK and the US. Please visit www.antisoma.com for further information about Antisoma.

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Source: Antisoma plc via Thomson Reuters ONE