Source: London Stock Exchange plc.

Protherics PLC announces Regulatory Application

CHESHIRE, UK--(Marketwire - November 20, 2008) -


Protherics PLC


VoraxazeTM rolling BLA submission initiated with the US FDA


London, UK; Brentwood, TN, US; 20 November 2008 - Protherics PLC
("Protherics" or the "Company"), the international biopharmaceutical
company focused on critical care and cancer, today announces that it
has commenced the submission of a rolling Biologics
License Application (BLA) for Voraxaze with the Food and Drug
Administration (FDA) in the US. This marketing application is being
made for the interventional use of Voraxaze for the rapid and sustained
reduction of methotrexate (MTX) in patients who have toxic MTX levels
due to impaired renal function.


Voraxaze contains an enzyme that breaks down MTX, a commonly used
cancer drug. It is an investigational new drug that is available in
the US under a Treatment Protocol for patients receiving high dose MTX
(? 1g/m2) who are experiencing, or at risk of, MTX toxicity. High
dose MTX is used to treat or prevent the recurrence of certain types of
cancer. Patients are considered at risk of MTX toxicity if they have
impaired renal function, which can lead to a delay in MTX elimination,
or have evidence of delayed elimination based on MTX levels. Voraxaze
is also available in Europe and elsewhere outside the US on a named
patient basis.


The development program for interventional use of Voraxaze has been
granted Fast Track designation by the FDA, enabling the submission of
the licensing application in sections rather than all components
simultaneously. The Voraxaze rolling BLA commenced today with
the submission of a pre-clinical data module. The remaining two modules
containing the CMC (chemistry, manufacturing and control) and
clinical data are scheduled for submission within the next 12 months,
as stipulated by the FDA. Protherics intends to seek a Priority Review,
reducing the time for the BLA review from 10 to 6 months from
submission of the final part of the application. This would allow a
potential marketing approval in US in 2010. Protherics estimates that
the global market potential for Voraxaze, for interventional use, is
approximately USD25-50m per annum.


Andrew Heath, Chief Executive of Protherics, commented: "The initiation of
the Voraxaze BLA submission represents a significant milestone towards e
nhancing
our portfolio of niche, specialty pharmaceutical products. Approval by
the FDA would provide an excellent opportunity for us to promote and
sell this important product in the US, alongside CroFabTM and DigiFabTM
when their US marketing rights are returned to us in 2010."


/ Ends /


For further information please contact:


Protherics

Ashley Tapp, Communication Manager     +44 (0) 7790 811 554

Saul Komisar, President Protherics Inc +1 615 327 1027


Financial Dynamics - press enquiries

London: Ben Atwell, Lara Mott          +44 (0) 20 7831 3113

New York: John Capodanno               +1 212 850 5600



Or visit www.protherics.com


Notes for Editors:


About Protherics

Protherics (LSE: PTI, NASDAQ: PTIL) is a
leading international biopharmaceutical company focused on specialist
products for critical care and cancer.


The Company has two critical care products, CroFabTM and DigiFabTM,
approved for sale in the US. The Company has the opportunity to
sell these products in the US from October 2010 together
with VoraxazeTM, a supportive cancer care product, following anticipated
approval in the US in 2010. Protherics is also developing a number of
other products in the cancer arena that it can commercialise in-house.


In addition, Protherics has several potential blockbuster products that
require development and commercialisation partners. These include
CytoFabTM which has been partnered by AstraZeneca in a major licensing
deal, and also Angiotensin Therapeutic Vaccine and
Digoxin Immune Fabs for which licensing partners will be sought in
2008-2009.  These products have the potential to be high value products
that can provide additional funding for the Company.


Protherics reported revenues of GBP26.1 million for the year ended 31
March 2008 and a strong cash balance of GBP37.7 million. With
headquarters in London, the Company has approximately 300 employees
across its operations in the UK, US and Australia.


On Thursday, 18th September Protherics announced a proposed merger with
BTG through a recommended share offer.


For further information visit www.protherics.com


About Methotrexate

Methotrexate (MTX) is a widely used anti-cancer drug which is often
used in high-doses (greater than1g/m2) in certain types of cancer.
However, MTX can result in reduced kidney function, particularly when
used in high doses. This further delays the elimination of methotrexate
from the body leading to mucositis, increased haematological toxicity
and increased risk of sepsis and in some instances death.


Disclaimer

This document contains forward-looking statements that involve risks
and uncertainties including with respect to products under development
and the progress and completion of clinical trials. Although we believe
that the expectations reflected in such forward-looking statements are
reasonable at this time, we can give no assurance that such
expectations will prove to be correct. Given these uncertainties,
readers are cautioned not to place undue reliance on such
forward-looking statements. Actual results could differ materially from
those anticipated in these forward-looking statements due to many
important factors discussed in Protherics' Annual Report on Form 20-F
and other reports filed from time to time with the U.S. Securities and
Exchange Commission. We do not undertake to update any oral or written
forward-looking statements that may be made by, or on behalf of,
Protherics.

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

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