Offer Update

NOT FOR RELEASE, PUBLICATION OR DISTRIBUTION, IN WHOLE OR IN PART, IN, INTO OR FROM CANADA, AUSTRALIA, JAPAN OR ANY OTHER JURISDICTION WHERE IT WOULD BE UNLAWFUL TO DO SO.

RECOMMENDED CASH OFFER FOR THE

ENTIRE ISSUED AND TO BE ISSUED SHARE CAPITAL

OF MINSTER PHARMACEUTICALS PLC

BY PROXIMAGEN NEUROSCIENCE PLC

OFFER DECLARED UNCONDITIONAL IN ALL RESPECTS

ANDOFFER EXTENDED TO 4 March 2010 

On 4 January 2010, the boards of Proximagen Neuroscience plc ("Proximagen") and Minster Pharmaceuticals plc ("Minster") announced the recommended offer by Proximagen for the entire issued and to be issued share capital of Minster (the "Offer"). The full terms of, and conditions to, the Offer and the procedure for acceptance were set out in the offer document issued by Proximagen on 14 January 2010 (the "Offer Document").

Level of Acceptances

As at 1:00 p.m. (London time) on 16 February 2010 (being the First Closing Date of the Offer), Proximagen had received valid acceptances from Minster Shareholders in respect of 50,805,875 Minster Shares representing approximately 86.25 per cent. of the existing issued share capital of Minster. These acceptances include acceptances received in respect of 32,891,853* Minster Shares (representing approximately 55.84 per cent. of the existing issued share capital of Minster) which were subject to irrevocable commitments procured by Proximagen from all of the Minster Directors and certain other shareholders.

As at 1:00 p.m. (London time) on 16 February 2010, Proximagen may count 50,805,875 Minster shares (representing approximately 86.25 per cent. of the existing issued share capital of Minster) towards the satisfaction of the acceptance condition to the Offer (as set out in paragraph 1 of Part A of Appendix I of the Offer Document.

* The 32,891,853 Minster Shares subject to irrevocable commitments as set out above, differs by 200 Minster Shares from the number of Minster Shares subject to irrevocable commitments as set out in the Offer Document. The difference is due to an administrative error in the Offer Document.

Reduction of Minimum acceptance condition

Proximagen has decided to reduce the minimum acceptance condition under the Offer as set out in paragraph 1 of Part A of Appendix I to the Offer Document from 90 per cent. to 75 per cent. in nominal value of the Minster Shares to which the Offer relates.

Proximagen confirms that the Offer has been accepted by Minster Shareholders holding in excess of 75 per cent. in nominal value of the Minster Shares to which the Offer relates and that the condition under the Offer as set out in paragraph 1 of Part A of Appendix I to the Offer Document (as amended) has been satisfied.

Satisfaction of Net Cash Balance Condition

Proximagen confirms that it is satisfied that the Net Cash Balance of Minster as at 16 February 2010 is in excess of £3,500,000 and accordingly the Condition set out in paragraph 2 of Part A of Appendix 1 has been satisfied.

Offer unconditional in all respects

As such, as at 1:00 pm (London time) on 16 February 2010, all the conditions under the Offer have now been satisfied (or, where applicable, waived) and the Offer has become unconditional in all respects.

The Offer will now remain open for acceptance by Minster Shareholders until 4 March 2010 when a further announcement will be made. Minster Shareholders who have not yet accepted the Offer are urged to do so as soon as possible and should follow the procedures for acceptance of the Offer set out below.

Deferred Consideration Shares

As the Offer is now unconditional in all respects, those persons with entitlements to Deferred Consideration Shares pursuant to the BioPartners Share Purchase Agreement will be issued their Deferred Consideration Share entitlements.

Procedure for acceptance of the Offer

To accept the Offer:

·; If you hold Minster Shares in certificated form (that is, not in CREST), the form of acceptance should be completed, signed, witnessed and returned together with your share certificate in accordance with the instructions contained in the Offer Document and the form of acceptance.

·; If you hold Minster Shares in uncertificated form (that is, in CREST), you should follow the procedure for electronic acceptance through CREST in accordance with the instructions set out in the Offer Document.

·; If you are entitled to receive Deferred Consideration Shares, you will shortly receive a letter from Proximagen explaining how to accept the Offer with respect to those Deferred Consideration Shares.

Settlement

Settlement of the consideration to which Minster Shareholders are entitled under the Offer will be effected by the despatch of cheques or the crediting of CREST accounts:

(i) in the case of acceptances received, valid and complete in all respects, on or before 16 February 2010, as soon as possible but not later than 14 days of such date; and

(ii) in the case of acceptances received, valid and complete in all respects, after such date but while the Offer remains open for acceptance, as soon as possible but not later than within 14 days of such receipt.

Directors

As disclosed in the Offer Document, the Minster Directors intend to resign immediately following the Offer becoming wholly unconditional.

Dr. Kenneth Mulvany and James Hunter have agreed to be appointed as directors of Minster together with its subsidiary Minster Research Limited, effective from the date of resignation of the current Minster Directors. Dr. Mulvany and Mr. Hunter are respectively Chief Executive Officer and Finance Director of Proximagen.

Cancellation to trading of Minster Shares on AIM

As set out in paragraph 12 of Part 2 of the Offer Document, as Proximagen has attained more than 75 per cent. of the voting rights in Minster, it intends to procure the making of an application by Minister to cancel admission to trading in Minster Shares on AIM. Such cancellation is anticipated to take place at 7.00 a.m. on 18 March 2010.

Cancellation of admission to trading of Minster Shares on AIM will significantly reduce the liquidity and marketability of all Minster Shares not assented to the Offer at that time and Minster Shareholders should be aware that, because the AIM Rules will cease to apply to Minster following the cancellation of admission to trading of Minster Shares on AIM, they will as a result, have more limited shareholder protections if they remain shareholders in Minster.

If you have any questions relating to the Offer Document, and the completion and return of the Form of Acceptance, please telephone Capita Registrars between 9.00am and 5.00 p.m. (London time) Monday to Friday on 0871 664 0321 from within the UK or +44 20 8639 3399 if calling from outside the UK. Calls to the 0871 664 0321 number cost 10 pence per minute (including VAT) plus your service provider's network extras. Calls to the helpline from outside the UK will be charged at applicable international rates. Different charges may apply to calls from mobile telephones and calls may be recorded and randomly monitored for security and training purposes. The helpline cannot provide advice on the merits of the Offer nor give any financial, legal or tax advice. Completion of the Offer remains subject to the satisfaction or, if permitted, waiver of the conditions to the Offer set out in the Offer Document.

In accordance with Rule 19.11 of the City Code, copies of the Offer Document, the form of acceptance and other documents required to be put on display for the purposes of the Offer will be available for inspection during normal business hours on any weekday (Saturdays, Sundays and public holidays excepted) at the offices of Reed Smith LLP, The Broadgate Tower, 20 Primrose Street, London EC2A 2RS throughout the period during which the Offer remains open for acceptance. A copy of this announcement, the Offer Document and the form of acceptance will also be available free of charge to view, subject to restrictions relating to persons located in jurisdictions where such availability is restricted, on Proximagen's website at www.proximagen.com and on Minster's website at www.minsterpharma.com. In addition, copies of the Offer Document and form of acceptance will be available from the offices of Capita Registrars, Corporate Actions, The Registry, 34 Beckenham Road, Beckenham, Kent BR3 4TU.

Terms defined in the Offer Document have the same meaning in this announcement.

17 February 2010

Enquiries:

This announcement is not intended to, and does not constitute, or form any part of an offer to sell or an invitation to purchase, otherwise acquire, subscribe for, sell or otherwise dispose of, any securities or the solicitation of an offer to purchase or subscribe for any securities in any jurisdiction, pursuant to the Offer or otherwise. Any acceptance or other response to the Offer should be made only on the basis of information contained in or referred to in the Offer Document and, in respect of Minster Shares held in certificated form, the form of acceptance

Evolution Securities Limited, which is authorised and regulated by the Financial Services Authority is acting as financial adviser and broker to Proximagen and for no-one else in connection with the Offer and will not be responsible to anyone other than Proximagen for providing the protections afforded to customers of Evolution Securities Limited or for affording advice in relation to the Offer or any other matters referred to in this document.

Nomura Code Securities Limited, which is authorised and regulated by the Financial Services Authority, is acting as financial adviser to Minster and for no-one else in connection with the Offer and will not be responsible to anyone other than Minster for providing the protections afforded to customers of Nomura Code Securities Limited or for affording advice in relation to the Offer or any other matters referred to in this document.

Distribution of Announcement

The distribution of this announcement and the availability of the Offer in jurisdictions other than the United Kingdom may be restricted by law and therefore any persons who are subject to the laws of any jurisdiction other than the United Kingdom should inform themselves about, and observe, any applicable requirements. This announcement has been made for the purpose of complying with English law and the City Code and the information disclosed may not be the same as that which would have been disclosed if this announcement had been prepared in accordance with the laws of jurisdictions outside England and Wales.

Copies of this announcement are not being, and must not be, directly or indirectly, mailed or otherwise forwarded, distributed or sent in or into or from any jurisdiction where to do so would violate the laws of that jurisdiction and persons receiving this announcement (including custodians, nominees and trustees) must not mail or otherwise forward, distribute or send it in, into or from any such jurisdiction. This announcement does not constitute an offer or an invitation to purchase any securities or a solicitation of an offer to buy any securities in any jurisdiction in which such offer or solicitation is unlawful.

The statements contained herein are made as at the date of this announcement, unless some other time is specified in relation to them, and the issue of this announcement shall not give rise to any implication that there has been no change in the facts set forth herein since that date. Nothing contained herein shall be deemed to be a forecast, projection or estimate of the future financial performances of Minster or Proximagen, except where otherwise stated.

Notice to US investors

The Offer is being made for securities of an English company and United States investors should be aware that this announcement, the Offer Document and any other documents relating to the Offer have been or will be prepared in accordance with the City Code and UK disclosure requirements, format and style, all of which may differ from those in the United States. Minster's financial statements, and all financial information relating to Minster that is included in this announcement or that may be included in the Offer Document or any other documents relating to the Offer, have been or will be prepared in accordance with UK generally accepted accounting principles and/or International Financial Reporting Standards and thus may not be comparable to financial statements of US companies.

This announcement does not constitute a Tender Offer Statement or a Solicitation/Recommendation Statement under the rules and regulations of the US Securities and Exchange Commission. The Offer will be made in the United States pursuant to applicable US tender offer rules and also in accordance with the requirements of the City Code.

The receipt of cash pursuant to the Offer by a US holder of Minster Shares will be a taxable transaction for US federal income tax purposes and under applicable US state and local, as well as foreign and other tax laws. Each holder of Minster Shares is urged to consult his independent professional adviser regarding the tax consequences of acceptance of the Offer.

Minster is incorporated under English law. All or some of the directors of Minster are residents of countries other than the US. As a result, it may not be possible for United States holders of Minster Shares to effect service of process within the US upon Minster or such directors of Minster or to enforce against any of them judgements of the United States predicated upon the civil liability provisions of the federal securities laws of the United States. It may not be possible to sue Minster or its officers or directors in a non-US court for violations of US securities laws.

Dealing Disclosure Requirements

Under the provisions of the Rule 8.3 of the City Code, if any person is, or becomes, "interested" (directly of indirectly) in one per cent. or more of any class of "relevant securities" of Minster, all "dealings" in any "relevant securities" of that company (including by means of an option in respect of, or a derivative referenced to, any such "relevant securities") must be publicly disclosed by no later than 3:30 p.m. (London Time) on the London business day following the date of the relevant transaction. This requirement will continue until the date on which the offer becomes, or is declared, unconditional as to acceptances, lapses or is otherwise withdrawn or on which the "offer period" otherwise ends. If two or more persons act together pursuant to an agreement or understanding, whether formal or informal, to acquire an "interest" in "relevant securities" of Minster, they will be deemed to be a single person for the purpose of Rule 8.3.

Under the provisions of Rule 8.1 of the City Code, all "dealings" in "relevant securities" of Minster by Proximagen or Minster, or by any of their respective "associates", must be disclosed by no later than 12:00 noon (London Time) on the London business day following the date of the relevant transaction.

A disclosure table, giving details of the companies in whose "relevant securities" "dealings" should be disclosed, and the number of such securities in issue, can be found on the Panel's website at www.thetakeoverpanel.org.uk.

"Interest in securities" arises, in summary, when a person has long economic exposure, whether conditional or absolute, to changes in the price of securities. In particular, a person will be treated as having as "interest" by virtue of the ownership or control of securities, or by virtue of any option in respect of, or derivative referenced to, securities.

Terms in quotation marks are defined in the City Code, which can also be found on the Panel's website. If you are in any doubt as to whether or not you are required to disclose a "dealing" under Rule 8, you should consult the Panel.