RNS Number:0506P
Protherics PLC
27 August 2003


27 August 2003

                                 PROTHERICS PLC

                FDA GRANTS ORPHAN DRUG DESIGNATION FOR VORAXAZE

Protherics PLC ("Protherics"), the international biopharmaceuticals company,
announced today that the U.S. Food and Drug Administration (FDA) has granted
orphan drug designation for Voraxaze, for the treatment of patients at risk of
methotrexate toxicity. Orphan drug designation was granted in Europe on 3
February 2003.

Voraxaze (Carboxypeptidase G2) is a new drug for the treatment of methotrexate
toxicity during cancer therapy. Voraxaze can very rapidly reduce dangerously
elevated serum methotrexate levels. Methotrexate is a widely used
chemotherapeutic agent that can cause kidney damage in a predictable number of
cases. Clinical trials involving over 200 patients have been completed in Europe
and the USA.

The market potential, when used as a rescue therapy, as well as for the
management of patients with signs of kidney damage during methotrexate
treatment, is estimated to be #80 million per annum.

Protherics anticipates gaining full FDA approval for Voraxaze followed by a
launch in the US within 2 years. A similar regulatory timeline is anticipated in
Europe. Sales on a named patient basis are anticipated to start in the current
financial year.

Andrew Heath, Chief Executive of Protherics said:

"The market exclusivity that orphan drug designation provides will allow us to
maximise our revenue stream from Voraxaze. With further trials, the availability
of an effective antidote opens up a much larger market opportunity for
Protherics, as high dose treatment protocols for methotrexate are adapted to
accommodate Voraxaze."

                                    - ENDS -

For further information contact:

Protherics PLC
Andrew Heath, Chief Executive: +44 (0) 20 7246 9950/+44 (0) 7919 480510 (mobile)

The Maitland Consultancy
Brian Hudspith: +44 (0) 20 7379 5151

Notes for Editors:

Orphan drug designation entitles Protherics to seven years exclusive marketing
rights for Voraxaze in the US following FDA approval, a fee waiver from the FDA
for its approval to market the product, and other benefits. The marketing
exclusivity conferred by the grant of Orphan drug designation in Europe is ten
years from market approval.

Protherics PLC

Protherics PLC was formed in September 1999 from the merger of Proteus
International plc and Therapeutic Antibodies Inc. Protherics is an international
biopharmaceutical company, engaged in the development, production and
commercialisation of immunopharmaceuticals and cancer therapies.

The Company's ordinary shares are listed on the Official List of the UK Listing
Authority and are traded on the London Stock Exchange. (PTI.L)

An electronic version of this will be available at: www.protherics.com


This release, and oral statements made from time to time by Company
representatives concerning the subject matter hereof, may contain so-called
"forward looking statements". These statements can be identified by introductory
words such as "expects", "plans", "will", "estimates", "forecasts", "projects",
words of similar meaning, and by the fact that they do not relate strictly to
historical or current facts. Forward-looking statements frequently are
discussing the Company's growth strategy, operating and financial goals, plans
relating to regulatory submissions and approvals and development programs. Many
factors may cause actual results to differ from the Company's forward-looking
statements, including inaccurate assumptions and a broad variety of risks and
uncertainties, some of which are known and others of which are not. Those and
other risks are described in the Company's filings with the Securities and
Exchange Commission, copies of which are available from the SEC or may be
obtained upon request from the Company. No forward-looking statement is a
guarantee of future results or events, and one should avoid placing undue
reliance on such statements.


                      This information is provided by RNS
            The company news service from the London Stock Exchange

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