26 September 2006 - Protherics PLC ("Protherics" or the "Company"), the international biopharmaceutical company focused on critical care and cancer, received notification from M&G Investment Management Limited on 25 September 2006 that, as at 22 September 2006, Prudential plc and certain of its subsidiary companies held a notifiable interest in 10,431,716 ordinary shares, representing 3.99% of the issued share capital of the Company.