Document:

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                                                                  Exhibit 10.2.3

Dated: 29 August 2006

                               (1) BIOVEX LIMITED

                                       AND

                              (2) DR. ROBERT COFFIN

                                   ----------

                                SERVICE AGREEMENT

                                   ----------

                                (WILMERHALE LOGO)

                                  Alder Castle
                                 10 Noble Street
                                London, EC2V 7QJ
                            Tel: +44 (0)20 7645 2400
                            Fax: +44 (0)20 7645 2424
                             Ref: DAA/0287572/00131

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THIS AGREEMENT is dated the 29th day August 2006

BETWEEN:

(1)  BIOVEX LIMITED a company registered in England and Wales under registered
     number 03480520 with its registered office is at 70 Milton Park, Abingdon,
     Oxford, OX14 4RX (the "COMPANY"); and

(2)  DR. ROBERT COFFIN of Flat 4, 43 Colville Gardens, London W11 2BA
     ("YOU/YOU").

1.   TITLE

     You will be employed by the Company as its Chief Scientific Officer and you
     will report to the Chief Executive Officer (or such other person as the
     Board may direct).

2.   JOB DUTIES

     You agree that you will:

2.1  devote the whole of your working time, attention and abilities to your
     duties for the Company, the Parent or their Group Companies under this
     agreement, unless you are absent from work due to ill health, incapacity,
     injury, authorised annual leave or at the Company's request;

2.2  faithfully and diligently perform your duties to the best of your ability,
     act in the best interests of the Company and its Group Companies at all
     times and use your best endeavours to promote and develop the best
     interests of the Company and any Group Companies;

2.3  without payment of additional salary or remuneration, accept any offices or
     directorships in the Company or any Group Company and perform such other
     duties and exercise such other powers in relation to the business of the
     Company or any Group Company as may from time to time be reasonably vested
     in or assigned to you by the Board;

2.4  obey the reasonable and lawful directions of the Board at all times and
     comply with any lawful rules, regulations and policies issued by the
     Company from time to time;

2.5  keep the Board (or the board of directors of any other Group Company for
     whom you are carrying out any duties) fully informed in a timely manner of
     any duties or activities you are undertaking on behalf of the Company or
     any Group Company in such form as the Board may reasonably require;

2.6  not obtain or accept, directly or indirectly, any discount, rebate, gift,
     commission, fees or other benefit from any third party in respect of any
     sale or purchase of goods or services by the Company or any Group Company;
     and

2.7  carry out your duties and exercise your powers jointly with any other
     person appointed by the Board in its discretion to act jointly with you.

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3.   OUTSIDE INTERESTS

3.1  You agree that, during your employment with the Company, you will not,
     without the prior written consent of the Board, be employed or engaged by,
     appointed as a director or officer of or be otherwise interested or
     concerned (including, but not limited to interests as shareholder, partner,
     investor or lender) in any other business, firm, company, corporation or
     organisation. The Company acknowledges that you currently undertake an
     academic role with University College London and the Company agrees that
     nothing in this Agreement (including this clause 3.1) will prevent you from
     continuing to undertake this role, provided that it does not interfere with
     your duties under this Agreement or create a conflict of interest with that
     of the Company or any Group Company. Without prejudice to your other
     duties, in the event of a conflict of interest (including a potential
     conflict or something which might reasonably appear to be a conflict) you
     agree to immediately report such matter to the Chief Executive Officer.

3.2  Notwithstanding any term of this agreement, you may hold (directly or
     through nominees including your spouse, partner or minor children) by way
     of bona fide personal investment any units of any authorised unit trust and
     up to 3% of the issued shares, debentures or other securities of any
     company whose shares are listed on a recognised investment exchange, on the
     AIM market of the London Stock Exchange plc, NASDAQ, the New York Stock
     Exchange or comparable markets.

3.3  During your employment you shall comply with all applicable rules of law
     and any policy, code, rules or regulations of the Company or any Group
     Company relating to dealings in shares, debentures or other securities of
     the Company and any Group Company or relating to any unpublished price
     sensitive information affecting the securities of the Company, any Group
     Company or any other company or corporation.

4.   FREEDOM TO TAKE UP EMPLOYMENT WITH THE COMPANY

     You undertake that by entering into this agreement or performing any of
     your duties for the Company you will not be in breach of any other
     agreement, contract or obligation binding on you.

5.   PERIOD OF CONTINUOUS EMPLOYMENT

     You agree that your employment with the Company and your period of
     continuous employment for the purposes of the Employment Rights Act 1996
     commenced on 12 February 1999. No period of employment with a previous
     employer will count as part of your period of continuous employment with
     the Company.

6.   TERM

6.1  Subject to clause 22 below and the remainder of this clause 6, this
     agreement (and hence your employment) may be terminated by either party to
     this agreement giving to the other party not less than 12 months' notice of
     termination of employment in writing.

6.2  Without prejudice to the Company's rights under clause 22 below, the
     Company may in its absolute discretion choose to terminate your employment
     immediately at any

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     time (whether or not notice of termination has been served by either party
     to this agreement) by making you a payment in lieu of notice within 14
     calendar days of the Termination Date equivalent to the basic salary that
     would have been paid to you by the Company during the unexpired period of
     notice due to you under clause 6.1 of this agreement. The payment in lieu
     of notice will not take into account any commission, bonus, holiday
     entitlement, incentives, car allowance, pension contributions, employee
     benefits that would have been paid or provided to you or otherwise
     applicable during the unexpired period of notice. The payment in lieu of
     notice will be subject to deductions for income tax, employee's national
     insurance contributions and other deductions required by law.

6.3  The normal retirement age for your position is 65.

7.   PLACE OF WORK

7.1  Your normal place of work will be the Company's main offices. The Company
     reserves the right to change your normal place of work, temporarily or
     permanently, to anywhere within or outside the United Kingdom (including,
     in particular, to the Parent Company's premises at 34 Commerce Way, Woburn,
     MA01801, USA) provided that the Company will give you at least three
     months' prior notice of any permanent change of location.

7.2  In the event that your normal place of work is moved to the United States,
     the Company will pay all reasonable relocation expenses in line with
     previous company practice.

7.3  You shall be required from time to time to travel to and work from such
     places within or outside the United Kingdom for such periods as the Company
     may reasonably require for the proper and efficient performance of your
     duties.

8.   SALARY

8.1  You will be paid a basic salary at the rate of L118,450 per annum, which
     shall be subject to deductions for income tax, employee's national
     insurance contributions and any other deductions required by law. Your
     salary will accrue on a day-to-day basis and will be payable monthly in
     arrears on or about the last working day of each month. Your salary is paid
     in respect of your duties both for the Company and any Group Company for
     whom you are required to work and includes any directors' fees due to you.

8.2  Your salary will be reviewed by the Company once each year, provided that
     there shall be no obligation on the Company to increase your salary as a
     result of any such review.

9.   EXPENSES

     You will be reimbursed all out-of-pocket expenses reasonably and properly
     incurred by you solely on the business of the Company or any Group Company
     provided you:

9.1  comply with any expenses policy of the Company in force from time to time;

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9.2  produce to the Company such receipts or other evidence of actual payment of
     the expenses concerned as the Company reasonably requires; and

9.3  submit all expense claims for any such expenses within three months of
     incurring the expenditure.

10.  PENSIONS, BONUSES AND OTHER BENEFITS

10.1 PENSION: You shall be entitled to join the Company's money purchase pension
     scheme (the "Plan"), subject at all times to the rules of the Plan in force
     from time to time (which may be varied from time to time at the discretion
     of the Company). The Company will contribute, by means of monthly
     instalments to the Plan, an annual sum equivalent to 10% of your basic
     annual salary in the applicable calendar year, subject at all times to:

     (a)  any contribution limitations prescribed by HM Revenue and Customs from
          time to time; and

     (b)  the rules of the applicable plan,

     both of which may vary from time to time.

10.2 BONUS SCHEME: Subject to the terms, conditions and rules of any applicable
     bonus plan in force from time to time and the successful achievement by you
     and by the Company of any targets, budgets or objectives determined by the
     Compensation Committee of the Parent for each year, you shall be eligible
     for a discretionary bonus of up to 30% of your basic annual salary at the
     applicable time. Whether each target or objective has been successfully
     completed, whether to pay any bonus and, if so, the amount of any bonus are
     matters within the discretion of the Compensation Committee of the Parent.
     You agree that the terms, conditions and rules applicable to the bonus plan
     may be varied from time to time in the absolute discretion of the Company
     and you acknowledge that the targets and objectives are likely to vary from
     year to year. The fact that a bonus is paid in one year is no guarantee
     that bonuses will be paid in subsequent years. As the bonus is intended to
     incentivise you to remain in the employment of the Company, the payment of
     any bonus is conditional on your being in the employment of the Company on
     the day the bonus is due for payment. All bonuses shall be subject to
     deductions for income tax, employee's national insurance contributions and
     any other withholdings required by applicable law.

10.3 EMPLOYEE BENEFITS: Subject to you and, where applicable, your spouse/civil
     partner or minor children meeting any conditions of eligibility on a
     ongoing basis (including those imposed by the relevant insurer and/or
     underwriter), the rules, terms and conditions of the applicable scheme at
     the relevant time (which may be varied from time to time at the absolute
     discretion of the Company) and to the Company being able to secure cover
     for you and, where applicable, your spouse/civil partner or minor children
     at rates which are reasonably acceptable to the Company, the Company will
     provide you, your spouse/civil partner and minor children with cover under
     its private medical expenses insurance scheme and will provide you (only)
     with cover under the Company's permanent health insurance scheme and life
     assurance scheme. The terms and conditions relating to the benefits
     provided under each scheme are as set out in the relevant insurance scheme
     that the Company has in force at the applicable time

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     (which will change from time to time during the term of this agreement).
     Any descriptions of the benefits stated in the staff handbook or elsewhere
     are provided for guidance purposes only and do not constitute binding terms
     and conditions of employment. You acknowledge that each insurance scheme
     includes detailed terms and conditions relating to your entitlement to
     benefits under any given circumstances, the level of cover and the
     cessation of the benefits. You are advised to obtain and review a copy of
     the terms and conditions of each insurance scheme, which are available from
     the Company's Human Resources Department.

     The Company reserves the right to withdraw any or all of these schemes at
     any time and/or to vary the schemes, the insurers, the rules, terms and
     conditions applicable to the scheme (including the eligibility conditions)
     or the level of cover at any time in its absolute discretion. You
     acknowledge and agree that you shall not be entitled to any benefits under
     any of the insurance schemes that may be provided for your benefit unless
     the claim is admitted and paid by the relevant insurance provider and that
     the Company shall have no obligation to take any legal action against any
     insurance provider in order to secure admission of any claim or payment of
     any benefits. Nothing in this agreement or in the rules, terms and
     conditions of any insurance scheme shall give rise to any express or
     implied limitations on the right of the Company to terminate your
     employment at any time in accordance with clause 6 or clause 22 of this
     agreement, provided that any insurance provider paying benefits to the
     Company under the Company's permanent health insurance scheme due to your
     incapacity agrees to pay the same level of benefits directly to you on the
     basis of and subject to the same substantive terms or conditions of cover
     (including the relevant definition of incapacity). You acknowledge and
     agree that you will not, following the termination of your employment by
     the Company in compliance with the terms of this clause, have any right of
     action or claims whatsoever against the Company arising from or in
     connection with the permanent health insurance scheme or the payment (or
     cessation of payment) of any benefits to you under the permanent health
     insurance scheme. You shall not have any express or implied right to
     receive any benefits or to the continuation of benefits following the
     termination of your employment.

11.  HOURS OF WORK

11.1 You agree to work such hours as may be necessary for the proper and
     efficient performance of your duties under this agreement and in any event
     not less that the normal working hours of the Company, as established from
     time to time.

11.2 You agree that the limit on average weekly working time set out in
     Regulation 4(1) of the Working Time Regulations 1998 will not apply to you.
     You acknowledge that you understand that your continued employment is not
     in any way conditional on you agreeing to this opt out of the 48 hour limit
     on your average working time during each week and you may therefore delete
     this clause 11.2 if you do not agree to opt out. After signing this
     agreement, you may opt back into the 48 hour average working week by giving
     the Company three months prior written notice.

12.  HOLIDAYS

12.1 The Company's holiday year runs from 1 April to 31 March.

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12.2 You will be entitled to 25 working days as paid annual leave in each
     holiday year, in addition to recognised English bank holidays. For the
     holiday year during which your employment commences or terminates, your
     holiday entitlement will be calculated on a pro rata basis.

12.3 All holiday must be authorised in advance by the Chief Executive Officer
     and must be taken at times that are convenient to the Company having due
     regard to the needs of the business of the Company or any relevant Group
     Company. For the avoidance of doubt Regulations 15(1) to 15(4) of the
     Working Time Regulations 1998 (dealing with dates when leave is taken) will
     not apply to your employment.

12.4 You may not, without the prior permission of the Chief Executive Officer,
     carry forward any unused part of your holiday entitlement to a subsequent
     holiday year. Subject to payments made under clause 12.6 below, the Company
     will not make any payment in lieu of holiday which has accrued, but has not
     been taken, by the end of any holiday year.

12.5 Following either party to this agreement giving notice to terminate this
     agreement, the Company may at its discretion require you to take, during
     the notice period, some or all of any holiday entitlement which will have
     accrued to you by the date of termination of your employment, but which you
     have not yet taken.

12.6 On the termination of your employment with the Company, the Company will:

     (a)  pay you in lieu of your accrued holiday, save that if you are
          dismissed for gross misconduct, the Company shall be under no
          obligation to pay you holiday pay in respect of accrued but untaken
          holiday in excess of any minimum holiday entitlement required by law
          for the year in question. Any payment in lieu of holiday entitlement
          will be subject to deductions for income tax, employee's national
          insurance contributions and other deductions required by law; or

     (b)  deduct an amount representing salary paid during holiday taken but not
          accrued by the date of termination of your employment from any
          payments due to you from the Company (including your final salary
          payment or any payment in lieu of notice) or, in the event that this
          is insufficient, require you to repay such amount to the Company as a
          debt within 7 days of the termination of your employment.

     Any payment in lieu, deductions or repayments in respect of holiday
     entitlement shall be calculated on the basis of one day's holiday giving
     rise to a payment in lieu equivalent to 1/260 of your basic annual salary.

13.  DEDUCTIONS FROM WAGES

     Without prejudice to any other rights open to the Company, you consent to
     the Company deducting from any wages due to you, (including Company sick
     pay) sums representing the amount of any outstanding loans or advances made
     to you by the Company, any overpayment of salary or expenses and payment
     made to you by mistake or through misrepresentation.

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14.  DATA PROTECTION

     In order to keep and maintain any records relating to your employment under
     this agreement and in order to record and monitor attendance, it will be
     necessary for the Company to record, keep and process personal data
     relating to you on computer and in hard copy form. Examples of personal
     data include: details of your disciplinary record; any grievances raised by
     you; the contents of your personnel file; and any sensitive personal data
     held by the Company such as your religious beliefs, your ethnic or racial
     origin and information relating to your physical and mental health.
     Further, in order to pay your salary and offer you the other benefits to
     which you may be entitled, the Company may also need to obtain from you
     details of your bank account and other financial information. To the extent
     that it is reasonably necessary in connection with your employment and the
     Company's responsibilities as an employer, you agree that this data may be
     disclosed to others, including other employees of the Company or any Group
     Company, the Company's professional advisers, the Inland Revenue or other
     taxation authority, the police and other regulatory authorities. You hereby
     consent to the recording, processing, use and disclosure by the Company of
     personal data relating to you as set out above (including the recording,
     processing, use and disclosure of your sensitive personal data to the
     extent required by reason of your employment or by law), including the
     transmission of such data abroad whether the recipient is located within or
     outside the European Economic Area.

15.  SICKNESS OR INJURY

15.1 If you are absent from work due to sickness, injury or accident you will
     notify a suitable member of staff of the Company as soon as possible.

15.2 If you are absent from work for less than 7 calendar days you will complete
     a self-certification form setting out the nature of your illness or
     incapacity on your return to work. If your absence continues for 7 calendar
     days or more you agree that you will on the eighth calendar day of such
     absence submit a doctor's certificate to the Company and that you will
     submit further doctor's certificate promptly to cover any continued period
     of absence.

15.3 Provided you comply with the notification and certification procedure set
     out above, the Company will pay your normal basic salary for 90 working
     days of absence due to illness, accident or injury in any period of 12
     months, whether or not such days of absence are consecutive. In the event
     that you exhaust your Company sick pay entitlement in any period of 12
     months:

     (a)  you shall not be entitled to any further Company sick pay until and
          unless you have returned to work for a consecutive period of not less
          than 3 calendar months;

     (b)  any further payments of enhanced Company sick pay will be made at the
          sole discretion of the Company;

     (c)  the Company will pay any statutory sick pay that may be due in
          accordance with the prevailing statutory sick pay regulations; and

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     (d)  the Company will pay any benefits due to you in accordance with the
          rules, terms and conditions stated in the Company's permanent health
          scheme, in accordance with and subject to the terms and conditions
          stated in clause 10.3 of this agreement.

15.4 You agree that, with effect from the date any benefits become payable to
     you under the Company's permanent health scheme, you:

     (a)  shall cease to be entitled to any salary, Company sick pay, other
          remuneration (save for the PHI benefits), car allowance, other
          allowances, bonuses, commission, pension contributions, life
          assurance, private medical insurance cover, stock options grants,
          incentives, or other employee benefits;

     (b)  shall cease to have any obligation to hold you out as its Chief
          Scientific Officer and the Company shall be entitled to appoint a new
          Chief Scientific Officer; and

     (c)  will, if requested to do so by the Board at any time, immediately
          resign from all directorships and other offices held by you in the
          Company or any Group Companies.

15.5 Failure to comply with the certification requirements set out above may
     result in your forfeiting your entitlement to be paid during periods of
     absence and in your facing disciplinary action.

15.6 Company sick pay paid to you at the discretion of the Company at any time
     shall include any statutory sick pay payable to you under the then
     prevailing rules of the statutory sick pay scheme. The Company may deduct
     from Company sick pay an amount or amounts equal to any state sickness
     benefit to which you are entitled.

15.7 The Company reserves the right to require you to undergo a medical
     examination by the Company's doctor or an independent medical practitioner
     in the event that you are unable to carry out your normal duties for the
     Company or are absent from work due to illness, accident or injury for not
     less than one month and you agree that the doctor or independent medical
     practitioner may disclose to the Company the results of the examination and
     discuss with the Company and its professional advisers any matters arising
     from the examination as might impair you from properly discharging your
     duties. You also authorise your own doctor to provide the Company's doctor
     and/or independent medical practitioner with any relevant extracts from
     your medical notes. This clause is without prejudice to your statutory
     rights, including your rights under the Access to Medical Reports Act 1988.

16.  CONFIDENTIALITY

16.1 During the course of your employment you will have access to and become
     aware of information which is confidential to the Company. You undertake
     that you will not, save in the proper performance of your duties, use
     (whether for your own benefit or for the benefit of any other person, firm,
     company or organisation) or disclose to any person, firm, company or
     organisation any of the trade secrets or other confidential information of
     or relating to (a) the Company; (b) any Group Company; (c) any customer or
     Prospective Customer (as defined below) of the Company or any Group

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     Company; (d) any person, firm, company or organisation with whom or which
     the Company is involved in any kind of business dealings, venture or
     partnership; or (e) the business of the Company or any Group Company, which
     (in the case of each of (a) through to (e)) you received or obtained in the
     course of your duties for the Company or as a result of your employment by
     the Company. You will likewise use your best endeavours to prevent the
     unauthorised publication or disclosure by any third party of any such trade
     secrets or confidential information.

16.2 The restriction stated in clause 16.1 above shall continue to apply after
     the termination of your employment, but shall cease to apply to information
     which must be disclosed by law or by an order of any court or tribunal of
     competent jurisdiction and to information which becomes available to the
     public generally (other than by reason of your breaching this clause).
     Nothing in this clause will prevent you making a "protected disclosure"
     within the meaning of Section 43A Employment Rights Act 1996, provided that
     you have first followed and exhausted any reasonable Company procedure in
     relation to the reporting of any alleged wrongdoing or malfeasance on the
     part of the Company or any Group Company or any of its/their officers,
     directors, employees or advisers.

16.3 For the purposes of this agreement confidential information shall include,
     but shall not be limited to:

     (a)  corporate, marketing, product development and business development
          strategies and plans;

     (b)  budgets, management accounts, bank account details and other
          confidential financial data;

     (c)  business, sales and marketing methods;

     (d)  details, designs, know-how, technical data, techniques, processes and
          specifications of or relating to any products and services being sold,
          provided, manufactured, distributed, researched or developed,
          including all: research and development reports and data; genetic
          data; databases; chemical formulae; information relating to
          pre-clinical or clinical trials; medical records; proprietary
          vaccines; vaccines; pharmaccines; anti-viral therapies; disease
          inhibitors; proprietary bioinformatics; proprietary elements or
          compounds (whether organic or inorganic); methods of manufacture;
          nucleotide or nucleotide sequence including DNA and RNA sequences;
          gene; vector or construct including plasmids, phages or viruses; host
          organism including bacteria, fungi, algae and protozoa; hybridomas;
          eukaryotic or prokaryotic cell line or expression system or any
          development strain or product of that cell line or expression system;
          protein including any peptide or amino acid sequence, enzyme, antibody
          or protein conferring targeting properties and any fragment of a
          protein or a peptide enzyme or antibody; drug or pro-drug; assay or
          reagent; any other genetic or biologic material or micro-organism;
          multi-cellular plants; data for the derivation of molecular structures
          including NMR spectra, X Ray diffraction patterns, and other primary
          experimental information, assignments and other calculations, required
          for determination of the structure, and co-ordinates of the derived
          molecular structure; and any intellectual property rights;

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     (e)  computer technology; computer programs; software applications and
          systems; information relating to proprietary hardware or software
          (including updates); source and object code to proprietary software;
          confidential algorithms developed or used for such proprietary
          software;

     (f)  details of the salaries, remuneration, fees, bonuses, commissions and
          other employment terms applicable to employees, officers and
          consultants;

     (g)  the names, addresses and contact details of any customers, Prospective
          Customers, suppliers, advisers, distributors, agents and other
          business partners, customer lists in whatever medium this information
          is stored and the requirements of those customers or the potential
          requirements of Prospective Customers for any products or services;

     (h)  the terms and conditions of business with customers, suppliers,
          advisers, distributors, agents and other business partners, including
          any pricing policy, discount policy or credit policy adopted and the
          terms of any partnership, joint venture or other form of commercial
          co-operation or agreement with any third party;

     (i)  software and technical information necessary for the development,
          maintenance or operation of any websites and the source and object
          code of each website;

     (j)  existing, pending or threatened litigation; and

     (k)  any other information which is the subject of an obligation of
          confidence owed to a third party, in particular the content of
          discussions or communications with any Prospective Customers or
          prospective business partners.

17.  DELIVERY UP OF THE COMPANY'S PROPERTY

17.1 You may not, save in the proper performance of your duties or with the
     prior permission of the Company, remove any property belonging to the
     Company or any Group Company, or relating to the affairs of the Company or
     any Group Company, from the Company's or any Group Company's premises, or
     make any copies of documents or records relating to the Company's or any
     Group Company's affairs.

17.2 Upon the Company's request at any time, and in any event on the termination
     of your employment, you will promptly deliver up to the Company or its
     authorised representative, any plans, keys, mobile telephone, security
     passes, credit cards, customer lists, price lists, equipment, documents,
     records, papers, computer disks tapes or other computer hardware or
     software or memory medium or devices (together with all copies of the
     same), and all property of whatever nature in your possession or under your
     control which belongs to the Company or any Group Company or relates to its
     or their business affairs. You will, at the Company's request, provide the
     Company without delay with a written statement confirming that you have
     complied with this obligation.

17.3 If, on the termination of your employment, you have any information
     relating to the Company or any Group Company or work you have carried out
     for the Company or

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     any Group Company which is stored on a device (which for the purpose of
     this agreement includes any personal computer, laptop computer, web-server,
     personal digital assistant, mobile telephone, memory, disk or any other
     storage medium) which device does not belong to the Company, you agree to
     disclose this fact to the Company immediately upon the termination of your
     employment and you agree to provide the Company with immediate access to
     the relevant device so that the Company may download the information and/or
     supervise its deletion from the device concerned. You will, at the
     Company's request, furnish the Company with a written statement confirming
     that you have complied with your duty of disclosure to the Company under
     this clause.

18.  COPYRIGHT AND DESIGN RIGHTS

18.1 You acknowledge and agree that the provisions of this clause 18 apply in
     respect of any works in which copyrights, design rights, or database rights
     (or similar forms of intellectual property protection) may exist which you
     have made or originated either by yourself or jointly with other people
     during your employment with the Company, but prior to the date of this
     agreement, as well as any such works which you may so make or originate
     after the date of this agreement.

18.2 You will promptly disclose to the Board all works in which copyrights,
     design rights or database rights (or similar forms of intellectual property
     protection) may exist which you have made or originated or which you make
     or originate either by yourself or jointly with other people during your
     employment whether before or after the date of this agreement.

18.3 Any copyright work, design or database which has been or may be created by
     you in the normal course of your employment, in the course of carrying out
     duties specifically assigned to you or which is capable of being used or
     exploited by the Company or any Group Company in its business operations,
     shall be the property of the Company whether or not the work was made at
     the direction of the Company or was intended for the Company and the
     copyright in it and the rights in any design or database shall belong
     absolutely to the Company throughout all jurisdictions and in all parts of
     the world, together with all rights of registration, extensions and renewal
     (where relevant).

18.4 To the extent that such copyrights, design rights and database rights (and
     similar forms of intellectual property protection) are not otherwise vested
     in the Company, you hereby assign the same to the Company, together with
     all past and future rights of action relating thereto. In relation to any
     copyright work, design or database that may created by you in the future,
     whether in the normal course of your employment, in the course of carrying
     out duties specifically assigned to you or which is capable of being used
     or exploited by the Company or any Group Company in its business
     operations, you hereby assign, by way of present assignment of future
     rights to the extent permissible by law, the copyrights, design rights and
     database rights (and similar forms of intellectual property protection) in
     the same to the Company, with the intention that such copyrights, design
     rights and database rights (and similar forms of intellectual property
     protection) should forthwith upon completion of the relevant works vest in
     the Company.

<PAGE>

18.5 You recognise and accept that the Company may edit, copy, add to, take
     from, adapt, alter and translate the product of your services in exercising
     the rights assigned under clause 18.3.

18.6 To the fullest extent permitted by law, you irrevocably and unconditionally
     waive any provision of law known as "moral rights" including any moral
     rights you may otherwise have under sections 77 to 85 inclusive of the
     Copyright Designs and Patents Act 1988 in relation to the rights referred
     to at clause 18.3. You give this waiver in favour of the Company and each
     Group Company, and all successors in title to and licensees of the
     copyright, design right and database right in such works (whether existing
     or future).

18.7 You agree that you will at the Company's request and expense, execute such
     further documents or deeds and do all things necessary or reasonably
     required to confirm and substantiate the rights of the Company under this
     clause 18 both before and after the termination of this agreement for any
     reason.

18.8 You agree that you will not at any time make use of, disclose or exploit
     the Company's property, trade marks, service marks, documents, materials or
     information in which the Company or any Group Company owns (wholly or
     partially) the copyright, design right or database right (or similar forms
     of intellectual property protection) for any purpose which has not been
     authorised by the Company.

19.  INVENTIONS

19.1 You acknowledge and agree that the provisions of this clause 19 apply in
     respect of any invention, discovery, design, improvement or other matter or
     work whatsoever made or discovered or to be made or discovered by you
     (whether alone or jointly with others) from time to time during the course
     of your employment with the Company whether before or after the date of
     this agreement.

19.2 It has been and it shall be part of your normal duties at all times to
     consider in what manner and by what new methods or devices, products,
     services, processes, equipment or systems of the Company and each Group
     Company might be improved and to further the intellectual property
     interests of the Company. You and the Company agree that, because of the
     nature of your duties and the particular responsibilities arising from your
     duties, you have had and continue to have a special obligation to further
     the interests of the Company.

19.3 You hereby acknowledge and agree that the sole ownership of any invention,
     discovery, design, improvement or other matter or work whatsoever made or
     discovered or to be made or discovered by you (whether alone or jointly
     with others) from time to time in the course of undertaking your normal
     duties for the Company or any Group Company under this agreement or in the
     course of carrying out duties assigned to you by the Company or any Group
     Company under this agreement, whether in each case before or after the date
     of this agreement, and all patents, trade secret rights and other
     intellectual property and proprietary rights therein ("Company Inventions")
     shall (subject to any contrary provisions of the Patents Act 1977, the
     Copyright Designs and Patents Act 1988 or any other applicable laws and to
     any rights of a joint inventor thereof) belong free of charge and
     exclusively to the Company or as it may direct.

<PAGE>

19.4 You shall promptly give to the Board full details of all inventions,
     discoveries, designs, improvements or other matter or works whatsoever made
     or discovered by you from time to time during your employment with the
     Company, whether before or after the date of this agreement.

19.5 All worldwide copyright, design rights and database rights in all Company
     Inventions shall be and remain the property of the Company and the
     provisions of clause 18 above shall apply in relation to the same.

19.6 You agree that you shall, at any time during your employment or thereafter,
     at the Company's expense, do all such acts and things and execute such
     documents (including without limitation making application for letters
     patent) as the Company may reasonably request in order to vest effectually
     all Company Inventions, to the extent that the same is the property of the
     Company or any other Group Company, and any protection as to ownership or
     use (in any part of the world) of the same, in the Company or any Group
     Company, or as the Company may direct, and you hereby irrevocably appoint
     the Company for these purposes to be your attorney in your name and on your
     behalf to execute and do such acts and things and execute any such
     documents as set out above.

19.7 You agree that you will not knowingly do or omit to do anything which will
     or may have the result of imperilling any such protection aforesaid or any
     application for such protection.

19.8 You agree that you will not at any time make use of, disclose or exploit
     any Company Invention belonging wholly or partially to the Company or any
     Group Company for any purpose which has not been authorised by the Company.

19.9 Each of the provisions in this clause 19 is distinct and severable from the
     others and if at any time one or more of such provisions is or becomes
     invalid, illegal or unenforceable, the validity, legality and
     enforceability of the remaining provisions of the clause will not in any
     way be affected or impaired.

20.  GARDEN LEAVE

     The Company shall be under no obligation to provide you with work during
     any period of notice of termination of employment (or any part thereof),
     whether such notice is given by the Company or by you (the "NOTICE
     PERIOD"). During the Notice Period, the Company may require you: (a) to
     carry out special projects or alternative duties provided that they are
     reasonably consistent with your status within the Company and your
     qualifications and skills; and/or (b) to cease carrying out some or all of
     your duties and powers for the Company or any Group Company; and/or (c) not
     to have any business dealings with the employees, suppliers, advertisers,
     customers and agents of the Company or any Group Company; and/or (d) not to
     attend at any premises or offices of the Company or any Group Company. You
     agree that you will, if requested to do so by the Board at any time during
     the Notice Period, immediately resign from all directorships and other
     offices held by you in the Company or any Group Companies. You will, during
     the Notice Period, continue to receive your salary and all contractual
     benefits provided by your employment. During the Notice Period you may not
     be engaged or employed by, take up any office or partnership in or be
     otherwise interested or concerned in any other company, firm, business or
     organisation without the prior

<PAGE>

     written permission of the Company. You will continue to owe the Company
     duties of good faith, fidelity and loyalty during the Notice Period and the
     provisions of this agreement will continue in force during the Notice
     Period unless otherwise stated in this clause 20.

21.  SUSPENSION

     In addition to the right to put you on garden leave set out in clause 20,
     the Company may suspend you on full pay pending the outcome of a
     disciplinary investigation or for health reasons. Whilst on suspension the
     Company may impose the same conditions as are applicable during garden
     leave.

22.  TERMINATION OF EMPLOYMENT

22.1 The Company may terminate your employment with immediate effect by serving
     written notice of immediate termination on you in the event that you:

     (a)  are, in the reasonable view of the Board, guilty of gross misconduct,
          wilful and serious neglect of duty, material dishonesty, gross
          incompetence or gross negligence;

     (b)  infringe (in a manner which the Board reasonably considers to be
          material or prejudicial to the interests of the Company or any Group
          Company) any rules or regulations imposed by any regulatory or other
          external authority or professional body applicable to your employment
          or which regulate the performance of your duties, the Company's
          business or the listing of the shares or securities of the Company or
          any Group Company on a recognised investment exchange or you fail to
          continue to possess any qualification or meet any condition or
          requirement laid down by any such applicable regulatory authority or
          professional body or by any legislation or regulations;

     (c)  act in a way which in the reasonable view of the Board brings you, the
          Company or any Group Company into material disrepute, whether or not
          such act is directly related to the affairs of the Company or any
          Group Company;

     (d)  breach clause 3.3 of this agreement, violate any rules of the Company
          relating to your dealings with the shares of the Company or any Group
          Company and/or enter into any transaction which contravenes the
          insider dealing provisions contained in the Criminal Justice Act 1993
          or any other statutory provision;

     (e)  become bankrupt, have an interim order made against you under the
          Insolvency Act 1986 or make any composition or enter into any deed of
          arrangement with your creditors or the equivalent of any of these
          under any other jurisdiction;

     (f)  are convicted of a criminal offence (other than a motoring offence for
          which you are not sentenced to any term of imprisonment, whether
          immediate or suspended); or

     (g)  become disqualified from acting as a director of a company or resign
          from any office you hold as a director of the Company or any Group
          Company

<PAGE>

          otherwise than at the written request of the Company or with the prior
          written consent of the Company.

22.2 In the event of the termination of your employment pursuant to clause 22.1,
     you shall not be entitled to receive notice of termination in accordance
     with clause 6.1 of this agreement or any payment in lieu of notice in
     accordance with clause 6.2 of this agreement.

22.3 You agree that you will, on the termination of your employment, transfer to
     the Company (or as the Company may direct) any shareholdings held by you on
     behalf of the Company or any Group Company, subject to and in accordance
     with the Company's articles of association from time to time.

23.  OBSERVER RIGHTS

23.1 Subject to clause 23.2 below, the Company will procure that you will be
     entitled to attend and participate (other than as to voting) in all
     meetings of the Board of the Parent Company in full as a nonvoting observer
     (including all meetings conducted by telephone and/or teleconference) and
     to receive copies of all notices, materials or documents distributed by the
     Parent Company to its directors.

23.2 The Parent Company shall reserve the right to exclude you from access to
     any materials, documents or meeting or portion thereof if the Parent
     Company believes on advice of its legal advisor that such exclusion is
     reasonably necessary to preserve attorney-client privilege, provided that
     you are informed of the existence of any such materials, documents or
     meeting or portion thereof and the general content thereof, together with a
     written or oral summary (and, if oral, followed up with a summary in
     writing provided by the Company's legal advisor if so requested by you) of
     such legal advice (with such redactions as may be necessary to preserve
     attorney-client privilege).

24.  OFFICES

24.1 If, for any reason, you shall either:

     (a)  resign, at the Company's request, as a director of the Company or any
          Group Company; or

     (b)  be removed from office as a director of the Company or any Group
          Company,

     then you agree that, notwithstanding your so ceasing to be a director of
     the Company or any applicable Group Company (as the case may be), your
     employment shall not terminate, there shall be no constructive dismissal,
     you shall continue to act as an executive employed by the Company on and
     subject to the terms and conditions otherwise set out in this agreement and
     you shall have no claim against the Company or any Group Company in respect
     of any loss of office.

24.2 You agree that you will, on the termination of your employment, resign
     immediately from all offices you hold in the Company and/or any Group
     Company.

24.3 You hereby irrevocably appoint the Company to be your attorney to execute
     any documents and do anything in your name to effect your resignation as a
     director of the

<PAGE>

     Company or any Group Company should you fail to resign following a request
     from the Company to do so in accordance with clause 24.2. A written
     notification signed by a director of the Company that any instrument,
     document or act falls within the authority conferred by this clause will be
     conclusive evidence that it does so.

25.  RESTRICTIONS AFTER TERMINATION OF EMPLOYMENT

25.1 You agree and covenant to the Company that you will not, without the prior
     written permission of the Board, during the period of 12 months immediately
     following the Termination Date (less any period you are required to cease
     undertaking any duties for the Company pursuant to clause 20 of this
     agreement), and whether on your own behalf or on behalf of any individual,
     company, firm, business or other organisation, directly or indirectly:

     (a)  in connection with the carrying on of any business which competes in
          the Restricted Area with the Business, solicit or entice away from the
          Company or any Group Company the business or custom of any customer or
          Prospective Customer (as defined below) with which customer or
          Prospective Customer you had business dealings on behalf of the
          Company or any Group Company during the Relevant Period or about which
          customer or Prospective Customer you are privy to confidential
          information at the Termination Date;

     (b)  in connection with the carrying on of any business which competes in
          the Restricted Area with the Business, accept any business, orders or
          custom from any customer or Prospective Customer of the Company or any
          Group Company with which customer or Prospective Customer you had
          business dealings on behalf of the Company or any Group Company during
          the Relevant Period or about which customer or Prospective Customer
          you are privy to confidential information at the Termination Date;

     (c)  in connection with the carrying on of any business which competes in
          the Restricted Area with the Business, endeavour to entice away from
          the Company or any Group Company any supplies of goods or services
          being provided to the Company or any Group Company by any person,
          firm, company or organisation whom or which supplied goods or services
          to the Company or any Group Company during the Relevant Period with
          whom you had business dealings on behalf of the Company or any Group
          Company in the course of the Relevant Period or about whom you are
          privy to confidential information at the Termination Date;

     (d)  in any way seek to affect the terms of business on which the Company
          or any Group Company deals with any person, firm, company or
          organisation whom or which was a customer, agent, distributor or
          contractor of or whom or which supplied goods or services to the
          Company or any Group Company during the Relevant Period or act or omit
          to act in any manner which will or is likely to result in any such
          person, firm, company or organisation terminating or reducing the
          amount of business dealings with or the custom, services or supplies
          it provides to or for the Company or any Group Company;

     (e)  solicit or seek to entice away from the Company or any Group Company
          any person employed or engaged by the Company or any Group Company as
          a

<PAGE>

          director, officer, president or a vice president or any other person
          employed or engaged in a managerial, technical, engineering, sales,
          marketing, research and/or development capacity at the Termination
          Date with whom you had dealings during the Relevant Period. This
          restriction shall apply regardless of whether the solicitation
          involves a breach of contract on the part of the consultant, director
          or employee concerned; or

     (f)  employ or engage or offer to employ or engage any person employed or
          engaged by the Company or any Group Company as a director, officer,
          president or a vice president or any other person employed or engaged
          in a managerial, technical, engineering, sales, marketing, research or
          product development capacity at the Termination Date with whom you had
          dealings during the Relevant Period. This restriction shall apply
          regardless of whether the employment involves a breach of contract on
          the part of the consultant, director or employee concerned.

25.2 You agree and covenant to the Company that you will not, without the prior
     written permission of the Board, for a period of 12 months immediately
     following the Termination Date (less any period you are required to cease
     undertaking your duties for the Company pursuant to clause 20):

     (a)  be engaged, appointed or employed within the Restricted Area by;

     (b)  undertake any duties in relation to the Restricted Area (wherever you
          are based) for; or

     (c)  be otherwise interested, concerned or involved in,

     (as the context permits) any person, firm, company, corporation, business
     or organisation which competes in the Restricted Area with the Business.

25.3 Each of the sub-clauses contained in clause 25 constitutes an entirely
     separate and independent covenant. If any restriction is held to be invalid
     or unenforceable by a court of competent jurisdiction, it is intended and
     understood by the parties that such invalidity or unenforceability will not
     affect the remaining restrictions or the validity of the rest of the
     agreement and that if any such restriction would be valid if some part
     thereof were deleted, such restrictions shall apply with such modification
     as may be necessary to make them effective.

25.4 You agree that if you receive an offer of employment, consultancy,
     directorship or other office or partnership during the continuance in force
     of any of the above, you will prior to acceptance of an offer, provide the
     party making the offer with copies of this clause and details of your
     notice period, the restrictions on your use and disclosure of confidential
     information and the clauses dealing with copyright and inventions.

25.5 You acknowledge that the Company is entering into this agreement not only
     for itself but also as the trustee of each Group Company and with the
     intention that the Company and/or any Group Company will be entitled to
     seek the protection of and enforce each of its restrictions directly
     against you. If requested to do so by the

<PAGE>

     Company, you will at any time enter into like restrictions as those
     contained in this clause 25 (mutatis mutandis) with any other Group
     Company.

25.6 Nothing in this clause 25 shall prohibit you from holding the investments
     and interests set out in clause 3.2 above.

25.7 Following the date upon which your employment terminates, you will not:

     (a)  represent yourself as being in any way connected with the business of
          the Company or any Group Company (except to the extent agreed by such
          Company); or

     (b)  carry on, cause or permit to be carried on any business under or using
          any name, trade mark, service mark, style, logo, get-up or image which
          is or has been used by the Company or any Group Company, or which in
          the reasonable opinion of the Company, is calculated to cause
          confusion with such a name, trade mark, service mark, style, logo,
          get-up or image or infer a connection with the Company or any Group
          Company.

26.  DISCIPLINARY AND GRIEVANCE PROCEDURES

26.1 The Company's disciplinary procedure shall apply to you, but may be
     modified by the Company to the extent that the Company determines to be
     reasonable to take into account your position in the Company. All
     disciplinary decisions will be taken by a director of the Company (other
     than you) and your right of appeal shall be to one of the non-employee
     directors or the Chairman of the Parent.

26.2 The Company's grievance procedure shall not apply to you. If you have any
     grievance relating to your employment you should write to the Board setting
     out full details of the grievance and providing all relevant information.
     You agree to promptly answer (in writing if so required) any questions put
     to you by any member of the Board in relation to such grievance. All
     grievances shall be determined by a director of the Parent and you shall
     have a right of appeal to one of the non-executive directors or the
     Chairman of the Parent.

27.  SECURITY

27.1 All communications, whether by telephone, email, fax, or any other means,
     which are transmitted, undertaken or received using the Company's
     information technology ("IT") or communications systems or Company property
     will be treated by the Company as work related and the Company's IT systems
     and network are provided for your use in undertaking your duties. You agree
     that the Company may intercept, record and monitor all such communications
     made by you and your use of the Company's IT systems and network without
     further notice. Accordingly, you should not regard any such communications
     or use as being private and matters which are private should be conducted
     by you outside of your working hours, away from the Company's premises and
     without use of the Company's communications and IT hardware, software,
     systems and networks.

27.2 The interception, recording and monitoring of communications is intended to
     protect the Company's business interests, for example, but without
     limitation, for the

<PAGE>

     purposes of quality control, security of communication and IT systems,
     protection of the Company's confidential information and legitimate
     business interests, record-keeping and evidential requirements, detection
     and prevention of criminal activity or misconduct and to assist the Company
     to comply with relevant legal requirements.

27.3 You agree that intercepted communications may be used as evidence in
     disciplinary or legal proceedings, including in any such action against
     you.

28.  COLLECTIVE AGREEMENTS

     There are no collective agreements which directly affect your terms and
     conditions of employment.

29.  PARTICULARS OF EMPLOYMENT

     This agreement includes the particulars of employment required by the
     Employment Rights Act 1996.

30.  RECONSTRUCTION OR AMALGAMATION

     If before the termination of this agreement, your employment is terminated
     by reason of the liquidation of the Company for the purposes of any
     reconstruction or amalgamation, and you are offered employment with any
     concern or undertaking resulting from such reconstruction or amalgamation
     on terms and conditions no less favourable than the terms of this
     agreement, then, to the extent permitted by law, you will have no claim
     against the Company in respect of the determination of your employment.

31.  ENTIRE AGREEMENT

31.1 This agreement is in substitution for and supersedes any previous service
     agreement, contract of employment or offer letter between the Company or
     any Group Company and you (including, without limitation, the service
     agreement between the Company and you dated 12 February 1999), all of which
     shall be deemed to have been terminated by mutual consent on the date this
     agreement comes into force and without giving rise to claims against the
     Company. You hereby acknowledge and warrant that this agreement states the
     entire agreement between the parties in relation to your terms of
     employment, that there are no agreements or arrangements whether written or
     oral or implied between the Company or any Group Company and you relating
     to your employment by the Company other than those expressly set out in
     this agreement and that you are not entering into this agreement in
     reliance on any representation not expressly set out in this agreement.

31.2 The termination of this agreement howsoever arising shall not affect any of
     the provisions of this agreement which are expressed to operate or have
     effect or are capable of operation or effect after such termination.

32.  NOTICES

     Any notice you are required to give under this agreement must be hand
     delivered to the Chief Financial Officer of the Parent at the Parent's
     principal executive office from time to time. Any notice the Company is
     required to give you will be hand

<PAGE>

     delivered to you or sent by recorded delivery post to your last notified
     home address. These notices will be deemed to have been given on the date
     of receipt if hand delivered and, if posted, on the day on which the letter
     would be delivered in the ordinary course of recorded delivery post.

33.  THIRD PARTIES

     This agreement constitutes an agreement solely between the Company and you,
     and, save where otherwise provided, for the purposes of the Contracts
     (Rights of Third Parties) Act 1999, nothing in this contract confers or
     purports to confer on a third party any benefit or any right to enforce a
     term of this contract.

34.  INTERPRETATION

34.1 Any reference in this agreement to:

34.2 any Act or delegated legislation includes any statutory modification or
     re-enactment of it or the provision referred to;

34.3 "BUSINESS" means any business, trade or other commercial activities of the
     Company or any Group Company operated at the Termination Date: (a) with
     which business of the Company or any Group Company you are concerned or
     involved to any material extent during the Relevant Period; or (b) in
     relation to which business of the Company or any Group Company you are
     privy to confidential information at the Termination Date;

34.4 "BOARD" shall mean the Board of Directors of the Parent from time to time
     or any person or any committee of the Board duly appointed by it;

34.5 "GROUP COMPANY" means each and every all company and/or corporation in any
     jurisdiction: (a) which from time to time is a subsidiary or a holding
     company of the Company; (b) which from time to time is a subsidiary of such
     holding company (excluding the Company); and (c) over which the Company or
     its holding company has control within the meaning of Section 416 of the
     Income and Corporation Taxes Act 1988 (and where the terms "SUBSIDIARY" and
     "HOLDING COMPANY" have the meanings attributed to them by section 736 of
     the Companies Act 1985);

34.6 "INCLUDE" and "INCLUDING" and "IN PARTICULAR" shall be construed as being
     by way of illustration only and shall not limit the generality of the
     preceding words;

34.7 "PARENT" means BioVex Group, Inc., a Delaware corporation and the sole
     shareholder of the Company.

34.8 "PROSPECTIVE CUSTOMER" means any person with whom the Company or any Group
     Company is in negotiations in relation to the sale or supply of goods
     and/or services by the Company or any Group Company to such person or to
     whom the Company or any Group Company has submitted a tender relating to
     such a sale or supply arrangement;

34.9 "RELEVANT PERIOD" means the period of 12 months immediately preceding the
     Termination Date, save where you are placed on garden leave and undertake
     no duties for the Company for part or all of the Notice Period ("GARDEN
     LEAVE"), in which case

<PAGE>

     the Relevant Period shall mean the period of 12 months immediately
     preceding the date upon which you commence Garden Leave;

34.10 "RESTRICTED AREA" means the United States of America, the United Kingdom
     and such other countries within which, on the date your employment
     terminates, the Company or any Group Company operates the Business and in
     relation to which country, during the Relevant Period, you:

     (a)  undertook material duties for the Company or any Group Company in
          relation to any part of the Business being operated in that country;
          or

     (b)  had a material degree of management responsibility for a material part
          of the Business being operated in that country; or

     (c)  were privy to confidential information relating to the Business; and

34.11 "TERMINATION DATE" means the date upon which your employment with the
     Company terminates howsoever arising.

35.  GOVERNING LAW

     Your terms of employment with the Company are governed by laws of England
     and the parties submit to the exclusive jurisdiction of the English courts.
     The Company may however enforce the agreement in any other courts of
     competent jurisdiction.

<PAGE>

IN WITNESS WHEREOF this agreement has been executed and delivered as a deed on
the date stated on the first page of this agreement.

EXECUTED AND DELIVERED AS A DEED
BY BIOVEX LIMITED
ACTING BY:                              /s/ Gareth Beynon
                                        ----------------------------------------
                                        Director

                                        /s/ P. Astley-Sparke
                                        ----------------------------------------
                                        Director/Secretary

EXECUTED AND DELIVERED AS A DEED
BY DR. ROBERT COFFIN:                   /s/ Robert Coffin
                                        ----------------------------------------

in the presence of:-

Signature of witness                    /s/ illegible
                                        ----------------------------------------
Name of witness                         Guy Simpson

Address of witness                      102 Albert Road

                                        /s/ illegible
                                        ----------------------------------------
Occupation of witness                   scientist<PAGE>

                                                                  Exhibit 10.6.1

(OXFORD THERAPEUTICS CONSULTING LOGO)

                                 THIS AGREEMENT

                    IS MADE ON THE 19TH DAY OF SEPTEMBER 2004

                                     BETWEEN

(1) BIOVEX LIMITED, 70 MILTON PARK, ABINGDON, OXFORD OX14 4RX ("THE CLIENT") AND

(2) OXFORD THERAPEUTICS CONSULTING LIMITED WHOSE REGISTERED OFFICE IS AT THE
MAGDALEN CENTRE, THE OXFORD SCIENCE PARK, OXFORD 0X4 4GA ("THE CONSULTANT")

<PAGE>

NOW IT IS AGREED:

1.   INTERPRETATION AND LAW

1.1  IN THIS AGREEMENT:

<TABLE>
<S>                              <C>
"Commencement Date"              means 19 September, 2004

"Client's Confidential           means all information confidential to the
Information"                     Client whether relating to the Client's
                                 business, customers, clients, suppliers or
                                 otherwise but excluding information now or at
                                 any time hereinafter becoming generally known
                                 or accessible to the general public (unless due
                                 to the default of the Consultant hereunder) and
                                 information obtained by the Consultant from a
                                 third party free of restrictions on use or
                                 disclosure.

"Consultant's Confidential       means all information confidential to the
Information                      Consultant whether relating to the Consultant's
                                 business, customers, clients, suppliers or
                                 otherwise but excluding information now or at
                                 any time hereinafter becoming generally known
                                 or accessible to the general public (unless due
                                 to the default of the Consultant hereunder) and
                                 information obtained by the Client from a third
                                 party free of restrictions on use or
                                 disclosure.

"Expenses"                       means all expenses properly incurred by the
                                 Consultant in providing the Services to the
                                 Client hereunder [including without limitation
                                 travel, accommodation and subsistence expenses
                                 and any honoraria paid by the Consultant to
                                 other advisers].
</TABLE>

                                        2

<PAGE>

<TABLE>
<S>                              <C>
"Fee"                            means the fees more particularly set out in the
                                 Fees Appendix annexed and payable in accordance
                                 with Clause 4 of this Agreement.

"Man Day"                        means the provision of the Services by any one
                                 of the Consultant's personnel (which shall
                                 include travelling time) to the client from
                                 7.30 a.m. to 7.30 p.m. on any week day subject
                                 to a minimum of 8 hours and "Man Hour" shall be
                                 construed and interpreted accordingly.

"Results"                        means all materials (including without limit
                                 software) to be provided to the Client by the
                                 Consultant as part of the Services, such
                                 materials being specified in the Results
                                 Materials Appendix.

"Services"                       means the services specified in the Services
                                 Appendix annexed hereto and including the
                                 services described in any documents referred to
                                 in the Services Appendix, such documents being
                                 annexed hereto.

"Term"                           means the period of 24 months commencing on the
                                 Commencement Date and expiring on 19 September
                                 2006.
</TABLE>

1.2  The headings in this Agreement are for convenience only and shall not
     affect its interpretation.

1.3  This Agreement shall be governed in all respects by English law and the
     parties hereby submit to the non-exclusive jurisdiction of the English
     courts.

                                        3

<PAGE>

2.   CONSULTANT'S OBLIGATIONS

2.1  The Consultant will provide the Services to the Client in accordance with
     this Agreement. For the avoidance of doubt nothing in this Agreement shall
     be construed as restricting or prohibiting the Consultant from at any time
     providing services (whether or not similar to "the Services") to any third
     party.

2.2  The Consultant will use all reasonable endeavours to provide the Services
     to the Client within the Term but all timings agreed to by the consultant
     are business estimates only (but given in good faith) and the Consultant
     will not be liable for any loss, injury, damage or expense arising directly
     or indirectly from any delay in respect of the Consultant's performance of
     its obligations hereunder.

2.3  Without prejudice to any other obligation of confidentiality from time to
     time subsisting between the Client and the Consultant, the Consultant
     hereby undertakes (subject to the Client's written consent) not at any time
     hereafter to disclose any Confidential Information to any third party nor
     to use any Client's Confidential Information save (in either case) as may
     be reasonably necessary for the purposes of providing the Services
     hereunder.

3.   CO-OPERATION BY CLIENT

3.1  The Client will as soon as is reasonably practicable after the signing of
     this Agreement make available to the Consultant (in a form readily
     accessible to the Consultant) all such information in the Client's
     possession or control as is materially relevant to the services and
     including without limitation the information and materials specified in the
     Materials Appendix annexed hereto.

3.2  The Client will promptly provide to the Consultant such further information
     as the Consultant may from time to time request.

3.3  The Client shall ensure that the person(s) named in the Personnel Appendix
     annexed hereto is/are available to the Consultant at all reasonable times
     for the purposes of liaison between the Client and the Consultant.

3.4  The Client will afford the Consultant every co-operation in relation to
     this Agreement and the provision by the Consultant of the services
     hereunder.

3.5  In the event that the Consultant requires information from the Client at

                                        4

<PAGE>

     any time then the obligations of the Consultant shall be suspended until
     the Consultant receives such information. If such information is delayed or
     withheld for more than 28 days then the Consultant may terminate this
     Agreement by notice to the Client on terms that the Client will pay to the
     Consultant the balance of the Fee [together with any further fees accrued
     due under Clause 4] and a sum equal to the Consultant's loss of profit
     resulting from such termination.

3.6  In the event that the Consultant finds it necessary or appropriate to
     disclose to the Client any Consultant's Confidential Information then
     without prejudice to any other obligation of confidentiality from time to
     time subsisting between the Client and the Consultant the Client hereby
     undertakes (subject to the Consultant's written consent) not at any time to
     disclose any Consultant's Confidential Information to any third party nor
     to use any Consultant's Confidential Information save (in either case) as
     may be reasonably necessary for the purposes of providing the Services
     hereunder.

4.   FEES, EXPENSES AND PAYMENT

4.1  In consideration for the provision of the Services to be provided by the
     Consultant under this Agreement, the Client agrees to pay the Consultant
     the Fees. All payments to the Consultant shall be made against the
     Consultant's invoices which shall be submitted to the client at the end of
     each calendar month during the provision of the Services in respect of work
     carried out during the period. All payments shall be made by the Client
     within 30 days of the Consultant's invoice for such fees by cheque or in
     such manner and currency as may be nominated by the Consultant.

4.2  The Consultant may at any time submit to the Client an invoice for
     Expenses. Invoices which are exclusively for Expenses (i.e. not including
     any Fees) are payable and will be paid by the Client within 30 days of the
     invoice date. Invoices which are for fees and for Expenses are payable and
     will be paid by the Client within 30 days of the Consultant's invoice.

4.3  If the Client fails to pay to the Consultant any sum due to the Consultant
     hereunder when due then without prejudice to any other right of the
     Consultant the Consultant may:

     4.3.1 charge the Client interest before and after any judgement on such
          overdue sums at a rate of 4% above the base rate per annum of the
          National Westminster Bank PLC from time to time in respect of sums
          which are overdue by no more than 60 days and

                                        5

<PAGE>

          at a rate of 6% above the base rate per annum of the National
          Westminster Bank PLC from time to item in respect of sums which are
          more than 60 days overdue, such interest to be charged weekly and
          compounded until payment of such overdue sums in full together with
          such interest; and/or

     4.3.2 suspend provision of the Services until payment of such overdue sums
          in full together with any interest charged under Clause 4.3.1.

5.   FORCE MAJEURE

Neither party shall be liable to the other under this Agreement for failure to
carry out its provisions to the extent that such failure is caused by any cause
beyond the parties' respective reasonable control including without limitation
fire, war, riot, sabotage, sickness or industrial action. The Client or the
Consultant (as the case may be) shall promptly inform the other party of the
existence of such conditions of force majeure. In the event that such conditions
of force majeure continue or are expected to continue for more than 2 months the
parties shall consult together in order to find a mutually acceptable solution.

6.   INTELLECTUAL PROPERTY RIGHTS

Unless otherwise provided in any Protocol specified in the Services the Client
shall not use any Results for the purpose of making any submission to a
regulatory body or for the purpose of any advertising or publicity without prior
review by the Consultant to ensure accuracy of presentation of any Results used.
Following review, written confirmation will be provided by the Consultant to the
Client, such confirmation not to be unreasonably withheld. In addition the
Client shall ensure that its use of the results does not contravene any law,
regulation or code of practice.

7.   LIABILITY

7.1  The Consultant will perform the Services with reasonable skill and care but
     will effect the Services on the basis that they are not required for any
     special purpose different from the usual purposes for which such Services
     are required and the Client shall be deemed to have full knowledge of the
     nature and consequences of the Services. It is the Client's responsibility
     to satisfy itself that the Services are suitable for its requirements and
     the Consultant does not profess to have any skill or judgement in relation
     to the particular needs of the Client.

7.2  Subject to the warranty given in Clause 7.1 and as otherwise expressly

                                        6

<PAGE>

     provided herein all warranties and conditions, express or implied by law or
     otherwise with respect to the Services are hereby excluded and the
     Consultant shall not be liable to the Client for any loss or damage
     whatsoever (including without prejudice to the generality of the foregoing
     any liability in contract, negligence or any other tort for any indirect,
     consequential or economic loss or for loss of profit or opportunity of any
     kind) arising directly or indirectly in connection with the Services or
     otherwise except insofar as any exclusion or limitation of the Consultant's
     liability hereunder is prohibited void or enforceable by law.

7.3  The Client is solely responsible for the use which it makes of the Results
     and for ensuring the safety and use of its products and for verifying the
     accuracy of all information comprised in the Results when used in
     promotional material or regulatory submissions.

7.4  The Client shall indemnify and hold harmless the Consultant from and
     against all losses, costs, claims, demands and expenses accruing to the
     Consultant arising out of any claim or cause of action with respect to any
     loss of or damage to any property or any personal injury or death of any
     person which is occasioned whether directly or indirectly by any act or
     omission (whether negligent or not) on the part of the Client, its agents
     or employees (including without limitation in respect of the use of the
     results by the Client).

7.5  Where under the Services to be provided by the Consultant, there is a need
     to effect contracts with third parties such contracts shall be made
     directly between the Client and the third party unless otherwise agreed by
     the Consultant and where the Consultant is charged with the negotiation of
     the terms of such contracts, it does so as the agent of the Client and
     without liability to the Client and/or the third party and the Client
     hereby acknowledges that:-

     7.5.1 it has sought and acts upon its own legal and professional advice as
          to the terms thereof; and

     7.5.2 does not rely upon any representation or warranty, implied or
          otherwise on the part of the Consultant that the contract with the
          third party is in a form appropriate and acceptable to enter into.

                                        7

<PAGE>

8.   TERMINATION

This contract may be terminated by either party at any time with six months'
written notice. Without prejudice to the rights of either party existing prior
to termination this Agreement may also be terminated by written notice:

8.1  Forthwith by the Consultant if the Client fails to pay to the Consultant
     when due any sum payable hereunder.

8.2  Forthwith by either party if the other party is in breach of this Agreement
     and fails in the case of a breach capable of remedy to remedy the same or
     in the case of a breach not capable of remedy to pay reasonable
     compensation in either case within 14 days of a written notice requiring
     the defaulting party to remedy such breach or (as the case may be) pay such
     reasonable compensation (which shall be specified in such notice).

8.3  Forthwith by the Consultant if the Client adopts a resolution for its
     winding up (unless the same be part of a solvent reconstruction or
     amalgamation) or if any petition is presented for the appointment of an
     administrator or a receiver or to wind up the Client or a receiver or an
     administrative receiver is appointed in respect of any part of the Client's
     undertaking or assets or if the Client suffers any other action in
     consequence of debt or any analogous event under any foreign jurisdiction
     occurs or if the Client is unable to pay its debts within the meaning of
     Section 123 of the Insolvency Act 1986 (or any re-enactment or further
     enactment thereof) or if the Client makes or attempts to make any
     arrangement or composition with or for the benefit of its creditors or
     ceases to carry on business.

9.   CONSEQUENCES OF TERMINATION

9.1  If this agreement is terminated by the Client in accordance with Clause 8.2
     (but not otherwise) then the Client shall be entitled to retain any
     materials provided to the Client by the Consultant in performing the
     services and to use such materials in accordance with Clause 6 but provided
     that the Client shall forthwith reimburse the Consultant all Expenses and
     pay to the Consultant all other sums accrued due hereunder together with a
     fair and reasonable proportion of the Fee and any further Fees accrued
     under Clause 4 taking into account the time spent by the Consultant in
     providing the Services.

9.2  If this Agreement is terminated by the Consultant in accordance with Clause
     8 (but not otherwise) then the Client shall forthwith at its own cost and
     as directed by the Consultant return to the Consultant or destroy

                                        8

<PAGE>

     all materials embodying any Results (and certify to the Consultant that it
     has done so), reimburse the Consultant all expenses and pay to the
     Consultant the balance of the Fee outstanding together with any further
     Fees accrued due under Clause 4 and a sum equal to the Consultant's loss of
     profit resulting from such termination and all outstanding licenses under
     the Intellectual Property Rights in the results shall forthwith and
     automatically be revoked.

10.  ASSIGNMENT AND SUBCONTRACTING

10.1 The Client will not assign any of its rights or obligations hereunder.

10.2 The Consultant may freely assign the whole or any part of this Agreement
     and may sub-contract any of the services in its absolute discretion
     notwithstanding the provisions of clause 7.5.

11.  RELATIONSHIP OF PARTIES

Neither party shall be deemed by virtue of this Agreement to be the agent or the
partner of the other and the Client and the Consultant will respectively each
make clear in all dealings with third parties that it has no authority to make
representations on behalf of the other or to bind the other contractually with
any third party.

12.  ENFORCEABILITY

If any of the terms hereof are held to be void or unenforceable by any reason of
law they shall be void or unenforceable to that extent only and no further and
all other terms shall remain valid and fully enforceable.

13.  AMENDMENTS ETC

This Agreement together with all documents (if any) referred to herein and
annexed hereto embodies the entire agreement of the parties in relation to the
Services and this Agreement may not be amended except in writing signed by the
authorised representatives of both parties.

14.  INDULGENCE

No indulgence granted by either party to the other in relation to any term
hereof shall be deemed a waiver of such term or prejudice the later enforcement
of that or any other term thereof.

15.  NOTICES

                                        9

<PAGE>

Any notice given hereunder shall be in writing and sent or delivered to the
address of the recipient party given above (or as from time to time otherwise
notified) by

     16.1 Facsimile transmission and in which case it will be deemed received
          when sent; or

     16.2 Hand (including courier) and in which case it will be deemed received
          when delivered; or

     16.3 Air Mail (where appropriate) and in which case it will be deemed
          received 5 days after posting; or

     16.4 Ordinary first class mail (where the recipient party is within the
          same jurisdiction as the server) and in which case it will be deemed
          received 2 days after posting.

17.  ARBITRATION

In the event of a dispute or difference between the parties as to the terms of
this Agreement or the Services to be performed or obligations operating as
between the parties, the matter shall be referred to the determination of an
independent arbitrator appointed by agreement between the parties or in default
of agreement by the President of the Institute of Arbitrators and who shall base
his determination upon English law and whose determination shall be final and
binding upon the parties.

                                       10

<PAGE>

                               PERSONNEL APPENDIX

     STAFF TO BE MADE AVAILABLE TO ASSIST IN THE PROVISION OF THE SERVICES

                                   Dr R Coffin
                                   Dr G Beynon
                                  Dr Colin Love
                               Dr Claire Shorrock
                                Dr Natasha Groves
                             Dr Magdalena Assenberg
                                 Dr Philip Reay

                                       11

<PAGE>

                                SERVICES APPENDIX

Range of services which may be provided for each project:

To prepare development plans for the client, together with budgets, time-frames
and decision points.

To identify, evaluate and assess and introduce potentially suitable contractors
capable of carrying out the respective elements of the Client's research
programme and suitable research and development facilities.

To project manage research and development projects including:-

(i)  supervision of contract research work being carried out for the Client.

(ii) assisting the Client in settling any specification of works and protocol in
     accordance with the Client's stated intentions or requirements.

(iii) negotiating commercial terms for the research project with the Client's
     chosen contractors to the point of the Client's making its final assessment
     and approvals before signing contracts.

(iv) preparation of regulatory documents such as GTAC submissions, CTA
     applications and Ethics Committee proposals to support clinical trials

To report on the conclusions of research work done for the Client with
recommendations.

To liaise regularly with the Client to monitor progress of the research and
development programmes

                                       12

<PAGE>

                                  FEES APPENDIX

The Client shall pay to the Consultant:

     L1400/L175.00 (from January 1, 2006) for each Man Day/Man Hour exclusive of
     Value Added Tax.

     Expenses charged at cost

     Petrol mileage at 60p/mile

                                       13

<PAGE>

AS WITNESS the hands of the duly authorised representatives of the parties the
day and year first above written:

FOR BIO VEX LIMITED

Signed: /s/ Colin Love                  15/4/6
        -----------------------------
Name: COLIN LOVE
Position: DEVELOPMENT DIRECTOR

FOR OXFORD THERAPEUTICS CONSULTING LIMITED

Signed: /s/ Janice Ann Steiner
        -----------------------------
Name: Janice Ann Steiner
Position: Director

                                       14

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