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

Protherics PLC

Notification of Major Interest in Shares

London, UK; Brentwood, TN, US; 20 November 2008 - Protherics PLC
("Protherics" or the "Company"), the international biopharmaceutical
company focused on critical care and cancer, announces that, on 19
November 2008, the following notification of interest in the ordinary
share capital of the Company was received from Aviva plc.

1. Reason for the notification     (please tick the appropriate
                                    box or boxes)

A disposal voting rights                X 

An acquisition or disposal of financial instruments which may
result in the acquisition of shares already issued to which
voting rights are attached

An event changing the breakdown of voting rights

Other (please specify): 

2. Full name of person(s) subject to the           Aviva plc & its
notification obligation:                           subsidiaries   

3. Full name of shareholder(s) (if different from  Registered 
Holder: 2.):

                                                   BNY Norwich Union
                                                   Nominees Limited   

                                                   Chase GA Group
                                                   Nominees Limited

                                                   Chase Nominees

                                                   CUIM Nominee Limited

                                                   Vidacos Nominees

                                                   *denotes direct

                                                   BNP Paribas - London

                                                   Chase Nominees

                                                   State Street
                                                   Nominees Limited  

                                                   Vidacos Nominees

4. Date of the transaction (and date on which the  18 November 2008threshold is crossed or reached if different):

5. Date on which issuer notified:                  19 November 2008

6. Threshold(s) that is/are crossed or reached:    13% to 12% Change
                                                   at Combined Interest

7. Notified details:

A: Voting rights attached to shares

Class/type             Situation previous 
of shares              to the Triggering  
if possible            transaction    
using the               
                       Number of               Number of voting     
                       Shares                  Rights
Shares                  45,971,166             45,971,166           

Resulting situation after the trigger transaction

Number of       Number of voting        & of voting rights
Shares          rights  

Direct           Direct     Indirect    Direct     Indirect           
30,591,694       30,591,694 14,733,097   8.73%      4.20%

B: Financial Instruments

Resulting situation after the triggering transaction 

Type of     Expiration Exercise/   Number of voting rights that  % of
financial   date       Conversion  may be acquired if the        voting
instrument             Period/     instrument is exercised/      rights
                       Date        converted. 


Total (A+B)

Number of voting rights % of voting rights

45,324,791              12.93%

8. Chain of controlled undertakings through which the voting rights and
/or the financial instruments are effectively held, if applicable :

The voting rights are managed and controlled by Aviva Investors Global
Services Limited, with the following chain of controlled undertakings:-

Aviva Investors Global Services Limited:

  - Aviva plc (Parent Company)

  - Aviva Group Holdings Limited (wholly owned subsidiary of Aviva plc)

  - Aviva Investors Holdings Limited (wholly owned subsidiary of Aviva
    Group Holdings Limited)

  - Aviva Investors Global Services Limited (wholly owned subsidiary of
    Aviva Investors Holdings Limited)

Proxy Voting:

9. Name of the proxy holder:                                          
                                       See Section 3

10. Number of voting rights proxy holder will cease to      

11. Date on which proxy holder will cease to hold voting    

12. Additional      Figures are based on a revised total number of
information:        voting rights of 350,427,481

/ Ends /

For further information please contact:


Nick Staples, Director of Corporate Affairs +44 (0) 7919 480510  

Julie Vickers, Company Secretary            +44 (0)1928 518010

Financial Dynamics - press enquiries

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

New York: John Capodanno                    +1 212 850 5600

Or visit

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


Contact Information: Contacts: RNS Customer Services 0044-207797-4400