For Immediate Release

19 August 2008

Name of applicant:

Alizyme plc

Name of scheme:

The Alizyme plc 2001 Unapproved Executive Share Option Scheme

Period of return:

From:

19 February 2008

To:

18 August 2008

Balance under scheme from previous return:

68,183

The amount by which the block scheme has been increased, if the scheme has been increased since the date of the last return:

Nil

Number of securities issued/allotted under scheme during period:

Nil

Balance under scheme not yet issued/allotted at end of period:

68,183

Number and class of securities originally listed and the date of admission:

800,000 ordinary shares of 2p each, admitted on 12 February 2007

Total number of securities in issue at the end of the period:

221,098,686 ordinary shares of 2p each fully paid

Name of contact:

David Campbell, Finance Director

Address of contact:

Alizyme plc, Granta Park, Great Abington, Cambridge, CB21 6GX

Telephone number of contact:

01223 896000