Cheshire, UK--(Marketwire - August 8, 2008) -


Protherics PLC


Notification of Major Interest in Shares



London, UK; Brentwood, TN, US; 8 August 2008 - Protherics PLC
("Protherics" or the "Company"), the international biopharmaceutical
company focused on critical care and cancer, announces that the
following notification of interest in the ordinary share capital of the
Company was received today from Aviva plc.



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

An acquisition  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): CHANGE TO THE TOTAL NUMBER OF VOTING RIGHTS
IN ISSUE

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   
                                                    6,741,190*


                                                   Chase GA Group
                                                   Nominees Limited
                                                    17,297,355*


                                                   Chase Nominees
                                                   Limited
                                                   979,009*   


                                                   CUIM Nominee Limited
                                                   5,150,906*


                                                   Vidacos Nominees
                                                   Limited
                                                   70,303*


                                                   BNP Paribas - London
                                                   636,429


                                                   Chase Nominees
                                                   Limited 
                                                   3,518,325


                                                   State Street
                                                   Nominees Limited  
                                                   9,577,375


                                                   Vidacos Nominees
                                                   Limited 
                                                   2,180,596       *denotes direct
                                                   interest  


4. Date of the transaction (and date on which the  6 August 2008   
threshold is crossed or reached if different):

5. Date on which issuer notified:                  8 August 2008   

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


7. Notified details:




A: Voting rights attached to shares

Class/type   Situation previous to Resulting situation after the trigger
ing
of shares    the Triggering        transaction
             transaction 
if possible
using the    Number of  Number of  Number of  Number of voting      % of
 voting
ISIN CODE    Shares     Voting     shares     rights                righ
ts
                        Rights 
                                   Direct     Direct     Indirect   Dire
ct Indirect

Ordinary                                                                
Shares
             40,890,879 40,890,879 30,238,763 30,238,763 15,912,725 8.88
%  4.68%
GB0007029209




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. 


N/A



Total (A+B)

Number of voting rights % of voting rights

46,151,488              13.56%




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

See Section 3



Proxy Voting:

9. Name of the proxy holder:                                See
                                                         Section 3

10. Number of voting rights proxy holder will cease to      
hold:

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



12. Additional       Figures are based on a total number of voting
information:         rights of 340,417,123





/ Ends /



For further information please contact:


Protherics 

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  www.protherics.com

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

END

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