COMUNICADO de Antisoma

Positive in vivo results for Antisoma's cancer drug DMXAA in

combination with chemotherapy

LONDON, 21 Ene. (PRNewswire) -

Antisoma plc (LSE: ASM, NASDAQ-Europe:ASOM), the UK-based

biopharmaceutical company specialising in the development of drugs to

treat cancer, today announces positive pre-clinical results for the

treatment of solid tumours with DMXAA when used in combination with

chemotherapy agents.

The studies were undertaken by the University of Auckland, New

Zealand, to examine the effect of combining a single dose of DMXAA

with single doses of nine widely-used chemotherapy agents in solid

tumour in vivo models. Neither DMXAA nor the chemotherapy drugs alone

provided prolonged delays in tumour growth or cures. However,

co-administration with DMXAA produced a significant delay in tumour

growth for eight of the nine chemotherapy drugs. The greatest effect

was seen with the chemotherapy agents Taxol® and Taxotere®. In the

combination of DMXAA with Taxol®, a median tumour growth delay of

29.5 days was observed and four of the eleven mice treated were

cured. The dose of Taxol® used, which was less than the maximum

tolerated dose, by itself had no significant activity on the tumour

with a median tumour growth delay of 0.3 days and no cures. In the

group treated with DMXAA alone, a median growth delay of 10 days was

seen and one of the seven mice treated was cured.

In the light of these findings, Antisoma plans to start a

clinical study with DMXAA in combination with chemotherapy by the end

of this year, following completion of a small dose-finding study in

patients.

DMXAA is a small molecule that selectively restricts the blood

flow through existing tumour blood vessels that feed tumour growth.

DMXAA also appears to cause the endothelial cells lining the blood

vessels to release substances that may sensitise tumours to

chemotherapeutic agents. The product has already completed two Phase

I studies where it was given by itself. It is Antisoma's intention to

develop DMXAA in combination with chemotherapy for a variety of

different solid tumours.

Commenting on the results, Glyn Edwards, Chief Executive Officer

of Antisoma, said: "These highly encouraging results show that DMXAA

has the potential to improve the efficacy of cancer treatment when

used in combination with many of today's chemotherapy regimes. We

believe that this drug may have a significant market potential in the

treatment of a wide variety of solid tumours."

Except for the historical information presented, certain matters

discussed in this statement 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.

Notes to Editors

Antisoma

Antisoma is a biopharmaceutical company developing novel products

for the treatment of cancer. Using its drug development experience,

the Company aims to produce safer and more effective tumour targeting

therapies for commercialisation by pharmaceutical partners. Antisoma

acquires the rights to promising new product candidates through

partnerships with internationally recognised academic or cancer

research institutions. These include the lead product candidate,

pemtumomab, which was licensed from the Imperial Cancer Research Fund

and is currently in a Phase III study as adjuvant treatment for

ovarian cancer, with designated Orphan Drug status in the US and EU.

There are three additional products in the clinical pipeline, Therex,

DMXAA and TheraFab, and several pre-clinical programmes of which

two, Angiomab and Thioplatin, are expected to enter clinical studies

in 2002. Visit www.antisoma.com for further information about

Antisoma.

DMXAA

DMXAA was discovered by Professors Bruce Baguley and William

Denny and their teams at the Auckland Cancer Society Research Centre

("ACSRC"), University of Auckland, New Zealand. Phase I human

clinical trials have provided safety data and indicate that DMXAA

causes a reduction in tumour blood flow when used alone. In extensive

studies in animal models, DMXAA used in combination with a number of

other anti-cancer agents - particularly taxanes - has been found to

control tumour growth. These results have been submitted for peer

reviewed publication. Antisoma intend to test DMXAA in combination

with chemotherapy.

Cancer Research Ventures (CRV)

DMXAA was in-licensed from Cancer Research Ventures Limited

(CRV). CRV is a technology transfer and development company

established by The Cancer Research Campaign in the UK to provide

technology transfer services to cancer researchers on a worldwide

basis. CRV, and its forerunner CRCT, have been providing these

services to UK researchers since 1987 and have recently expanded the

business into Europe and further afield through the affiliate company

Biotech Research Ventures in Singapore. CRV has been instrumental in

establishing a number of successful biotech companies in the UK.

Source: Antisoma plc

Contact: Glyn Edwards, Chief Executive Officer Tel: +44 (0)20 8799

8200; Financial Dynamics, Jonathan Birt, Tel: +44 (0)20 7831 3113

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