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                                                                   EXHIBIT 10.7

                             Dated 12 FEBRUARY 1999

                                NEUROVEX LIMITED

                                     - and -

                            PROFESSOR DAVID LATCHMAN

                  --------------------------------------------
                         CONSULTANCY SERVICES AGREEMENT
                  --------------------------------------------

                                 Cameron McKenna
                                   Mitre House
                              160 Aldersgate Street
                                 London EC1A 4DD

                               T +44(0)171367 3000
                               F +44(0)171367 2000

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                                TABLE OF CONTENTS

<TABLE>
<S>      <C>                                                                <C>
1.       DEFINITIONS AND INTERPRETATION...............................       1
2.       NATURE OF ENGAGEMENT.........................................       1
3.       COMMENCEMENT DATE............................................       2
4.       CONSULTANCY FEE..............................................       2
5.       EXPENSES.....................................................       3
6.       INDEPENDENT CONTRACTOR STATUS................................       3
7.       CONFLICTS OF INTEREST........................................       4
8.       CONFIDENTIALITY..............................................       6
9.       INTELLECTUAL PROPERTY........................................       7
10.      INCAPACITY...................................................       8
11.      TERMINATION OF AGREEMENT.....................................       8
12.      GENERAL......................................................       9

SCHEDULE 1 DEFINITIONS AND INTERPRETATION.............................      11

SCHEDULE 2 EXISTING COMMITMENTS.......................................      14
</TABLE>

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THIS AGREEMENT is made the 12th day of FEBRUARY 1999

BETWEEN:

(1)      NEUROVEX LIMITED whose registered office is at Marquis House, 67/68
         Jermyn Street, London W1Y 6NY ("the Company")

(2)      PROFESSOR DAVID LATCHMAN of 9 Gresham Gardens, London NW11 8NX
         ("Professor Latchman")

WHEREAS:-

(A)      The Company wishes to engage Professor Latchman to perform consultancy
         services on the terms set out below.

(B)      Professor Latchman is a full time employee of University College
         London, employed to carry out scientific research and is involved in
         scientific research in fields of particular interest to the Company.

(C)      Professor Latchman is free to accept such engagement on the terms set
         out below.

IT IS AGREED as follows:-

1.       DEFINITIONS AND INTERPRETATION

1.1      The Definitions set out in the Schedule apply in this Agreement which
         shall be interpreted in accordance with the rules of interpretation
         also set out in the Schedule.

2.       NATURE OF ENGAGEMENT

2.1      The Company engages Professor Latchman and Professor Latchman accepts
         engagement as a consultant who will provide consulting services to the
         Company in respect of gene delivery vectors so long as such services do
         not go beyond consulting in respect of the Field ("the Services"). For
         the avoidance of doubt, the Board may not require Professor Latchman to
         provide services which may conflict with his Existing Commitments as
         set out in Schedule 2.

2.2      Prior to entering into this Agreement, Professor Latchman was employed
         and continues to be employed by University College London
         ("University") the company acknowledges, that in connection with
         Professor Latchman's employment by the University, Professor Latchman's
         sole responsibility is to the University.

2.3      Professor Latchman will (unless unavoidably prevented from doing so by
         reason of ill health, prior teaching or other academic commitments, any
         necessary attendance at scientific conferences or otherwise) provide
         the Services at such

                                       -1-

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         other times as may be reasonably requested by the Company on a
         "when-needed" basis for up to 1 day each week, unless otherwise agreed
         with University.

2.4      Professor Latchman shall:-

         2.4.1    perform the Services to the best of his ability in an expert
                  and diligent manner and in such a way as at all time to
                  promote the best interests of the Company and
                  the Group;

         2.4.2    faithfully and diligently perform his duties and exercise only
                  such powers as are consistent with them;

         2.4.3    obey all and any lawful and reasonable directions of the
                  Board;

         2.4.4    keep the Board promptly and fully informed (in writing if so
                  requested) of his conduct in relation to the business or
                  affairs of the Group and provide such explanations as they may
                  require;

         2.4.5    not at any time make any untrue or misleading statement
                  relating to the Group.

2.5      Professor Latchman shall perform the Services at the Company's
         laboratory and office at Windeyer Buildings, 46 Cleveland Street,
         London W1P 6DB (and/or such other place of business of the Group as the
         Board may reasonably require from time to time consistent with the
         Consultant's duties). Professor Latchman will, if an for as long as
         required by the Company, make visits in the ordinary course of his
         duties to such places anywhere in the world as the Company may
         reasonably specify having regard to Professor Latchman's other
         commitments.

2.6      Professor Latchman warrants that, by entering into this Agreement, he
         is not in breach of any express or implied term of any contractual or
         other obligation to any third party which is binding on him and in
         particular University has, to the extent required, consented to
         Professor Latchman entering into this Agreement.

3.       COMMENCEMENT DATE

         This Agreement will start on 12 February 1999 ("Commencement Date") and
         will continue (unless earlier terminated according to its terras) until
         terminated by either party on 6 months' written notice.

3.1      Provided that no other provision of this Agreement will cease to have
         effect by reason of the operation of this Clause.

4.       CONSULTANCY FEE

4.1      The Company will pay Professor Latchman an annual fee at a rate of
         (pound) 25,000 each year (plus VAT where applicable) (or at such higher
         rate as may be awarded to Professor Latchman pursuant to Clause 4.3)
         which will accrue from day to day and be payable in equal monthly
         instalments in arrears on or about the last

                                       -2-

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         working day of each month ("the Fee"). The Fee covers any and all
         duties performed by Professor Latchman pursuant hereto.

4.2      The fee shall be payable within 5 business days of receipt by the
         Company of an invoice from Professor Latchman in respect of the
         Services for each month.

4.3      On or about 1 November of each year, commencing on 1 November 1999,
         Professor Latchman's fee will be reviewed and the rate of fees then
         payable may be (but will not necessarily be) increased by the Company
         with effect from the date of such review and Professor Latchman may be
         awarded such bonus, share option or other performance related benefits
         as the Company's remunerating committee decides in its sole discretion.

4.4      Professor Latchman may at the absolute discretion of the Company be
         considered for participation in one or more Company share option plans
         to be established subject to and in accordance with the rules of such
         plan(s).

5.       EXPENSES

5.1      Within 30 days of receipt of a monthly expenses invoice from Professor
         Latchman supported by the appropriate vouchers or other proof of
         payment the Company will reimburse Professor Latchman for all expenses
         described in that invoice which have been reasonably incurred by him in
         providing the Services including but not limited to travel, hotels,
         meals, telephone, fax and express delivery services. If Professor
         Latchman incurs expenses which relate partly to the performance of the
         Services and partly to his other interests then the Company will
         reimburse Professor Latchman for an appropriate proportion of the
         expenses.

6.       INDEPENDENT CONTRACTOR STATUS

6.1      Professor Latchman acknowledges and agrees that he is an independent
         contractor and that this consulting arrangement will not give him any
         rights to any pension, insurance, car or other fringe benefits from the
         Company except as expressly contemplated by this Agreement.

6.2      Professor Latchman agrees to indemnify and hold the Company harmless
         from any income tax due on payments to Professor Latchman under this
         Agreement or the amount of such payments grossed up at the applicable
         rate of tax if the Inland Revenue deems payments made to be payments
         net of tax, together with any penalties and interest which may be
         levied on the Company in respect of income tax deductions which the
         Inland Revenue determines should have been made from payments to
         Professor Latchman made pursuant to this Agreement.

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7.       CONFLICTS OF INTEREST

7.1      Professor Latchman shall not without the prior written permission of
         the Board act (whether as a consultant, advisor, director, employee or
         otherwise) for or collaborate with any other company, firm, business
         which:

         7.1.1    carries or it is intended to carry on research and associated
                  business actively in the Field save where Professor Latchman
                  acts as a consultant, advisor, director, employee or otherwise
                  for such company, firm or business outside the Field;

         7.1.2    which carries out research, development or a business in
                  competition with or in a business which is the same as or
                  similar to any business of the Company save where Professor
                  Latchman acts as a consultant, advisor, director, employee or
                  otherwise for such company, firm or business outside the
                  Field;

         7.1.3    might impair his ability to act at all times in the best
                  interests of the Company; or

         7.1.4    requires him to disclose Confidential Information in order
                  properly to discharge his obligations to or to further his
                  interest in such company, firm or business.

7.2      For the avoidance of doubt the Existing Commitments listed as outlined
         in Schedule 2 including any extensions thereto have been approved by
         the board.

7.3      Professor Latchman shall not directly or indirectly:-

         7.3.1    for the period of 12 months after the termination of his
                  engagement hereunder be engaged or concerned or interested in
                  any business carried on within the Restricted Area wholly or
                  partly in competition with any Restricted Business.
                  "Restricted Area" means the United Kingdom, Europe, the United
                  States of America and any other country in which the Company
                  carries on or to the knowledge of the consultant intends to
                  carry on any Restricted Business as at the termination of his
                  employment. "Restricted Business" means research and
                  development activities in the Field and all or any other
                  commercial activities carried on or to be carried on by the
                  Company in which Professor Latchman worked or about which
                  Professor Latchman knew Confidential Information to any
                  material extent at any time during the final two years of his
                  engagement;

         7.3.2    for the period of 12 months after the termination of his
                  engagement hereunder, induce or attempt to persuade any
                  Employee to leave employment or engagement by the Company or
                  offer employment or engagement to any Employee. An "Employee"
                  is any person who is and was, at any time during the period of
                  two years prior to the termination of Professor Latchman's
                  engagement, employed or engaged by the Company or any Group
                  Company in a senior management, senior

                                       -4-
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         technical or senior sales position and who, by reason of such
         position, possesses any Confidential Information or is likely to be
         able to solicit the custom of any customer of the Company or any Group
         Company or to induce any such customer to cease dealing with the
         Company or any Group Company, were he to accept employment or
         engagement in a business which is similar to or in competition with
         any Restricted Business;

7.3.3    at any time, before or after the termination of his engagement, induce
         or seek to induce, by any means involving the disclosure or use of
         Confidential Information or otherwise, any customer of the Company to
         cease dealing with the Company or to restrict or vary the terms upon
         which it deals with the Company;

7.3.4    at any time after the termination of his engagement directly or
         indirectly to disclose or make use of any Confidential Information;

7.3.5    at any time after the termination of his engagement, represent himself
         or permit himself to be held out as having any connection with or
         interest in the Company.

7.3.6    for the period of 12 months after the termination of his engagement,
         deal with, seek employment with, be employed or engaged by or engage in
         business with any customer of the Company of any Group Company or work
         on any account or business of any customer of the Company or any Group
         Company for the purpose of providing that customer with services which
         are the same as or similar to any services which he was involved in
         providing to that customer at any time in the 12 months preceding the
         termination of his engagement;

7.3.7    for the period of 12 months after the termination of his engagement,
         solicit business from any customer of the Company or any Group Company
         for the purpose of providing to that customer services which are the
         same as or similar to those which he has been involved in providing to
         that customer at any time in the 12 months preceding the termination of
         his engagement;

7.3.8    interfere or seek to interfere with contractual or other trade
         relations between the Company or any Group Company and any of its or
         their suppliers; or

7.3.9    communicate to any person, concern, undertaking, firm or body corporate
         anything which is intended to or which will or may damage the
         reputation or good standing of the Company or any Group Company;

For the avoidance of doubt nothing in the above clause shall restrict Professor
Latchman from taking or continuing any employment the sole purpose of which is
academic research, meaning research otherwise for commercial gain. Each
restriction in this Clause 7.3 (whether drafted separately or together with
another) is independent and severable from the other restrictions and
enforceable

                                       -5-
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         accordingly. If any restriction is unenforceably for any reason but
         would be enforceable if part of the wording were deleted, it will apply
         with such deletions as may be necessary to make it enforceable.

8.       CONFIDENTIALITY

8.1      Professor Latchman shall

         8.1.1    abide by all directions of the Board from time to time
                  concerning the use, disclosure and supply of Confidential
                  Information;

         8.1.2    not disclose or supply to any third party outside the Company
                  any or all of the Confidential Information without the prior
                  permission of the Board and without adhering to the Company's
                  standard operating practices with regard to such disclosure or
                  supply;

         8.1.3    for the period of his engagement pursuant to this Agreement
                  use his best endeavours to prevent the publication, disclosure
                  or unauthorised use of any Confidential Information.

         8.1.4    not without the prior permission of the Board make any
                  statements on the Company's behalf or concerning the Company
                  to the press, media, venture capitalists, brokers, banks,
                  financial analysts and/or any other Professor Latchman
                  unconnected with the Company.

         8.1.5    not without the prior authority of the Company remove from
                  Company premises or copy or allow others to copy the contents
                  of any Document, which contains any Confidential Information
                  or which belongs to the Company;

         8.1.6    return to the Company on request all Documents in his
                  possession or under his control which belong to the Company or
                  which contain or refer to any Confidential Information;

         8.1.7    if so requested by the Company, delete all Confidential
                  Information from any computer disks, tapes or other re-usable
                  material in his possession or under his control and deliver up
                  or destroy all other Documents and tangible items in his
                  possession or under his control which contain or refer to any
                  Confidential Information or which belongs to the Company and
                  shall give an undertaking to the Company to this effect.

8.2      The obligations set out in this Clause 8 shall survive the expiry or
         termination of this Agreement for whatever reason for a period of 3
         years thereafter or until such times as the Confidential Information
         comes into the public domain, whichever it the earlier.

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9.       INTELLECTUAL PROPERTY

9.1      Professor Latchman shall make full and prompt disclosure to the Company
         of any and all Know How (including in particular inventions) conceived,
         originated or reduced to practice by Professor Latchman during the
         period of this Agreement in connection with the performance of the
         Services and shall promptly supply to the Company any and all Materials
         and Documents created originated or reduced to practice by Professor
         Latchman during the period of this Agreement in connection with the
         performance of the Services. This obligation shall apply whether or not
         the Professor Latchman has conceived, created or originated said Know
         How, Materials or Documents alone or jointly with others and whether or
         not on the premises of the Company or during normal working hours.

9.2      Professor Latchman shall not make any filings for Patent Rights in
         respect of any inventions made by him the subject of Clause 9. Any and
         all such filings shall be made by the Company and any resulting Patent
         Rights shall as between Professor Latchman and the Company be
         exclusively owned by the Company.

9.3      Professor Latchman shall assign to the Company (or any person or entity
         designated by the Company) all Person's right, title and interest in
         and to any and all Know How, Materials and Documents the subject of
         Clause 9 and hereby irrevocably and unconditionally waives any or all
         claims to moral rights in any such items.

9.4      Professor Latchman agrees both during and after the term of this
         Agreement to do or procure the doing of all such acts and things and to
         sign or procure the signing of all such deeds and documents as the
         Company may in its sole discretion require from time to time without
         limitation in connection with the filing, prosecution, maintenance and
         renewal of Patent Rights and the making of assignments provided always
         that the Company shall bear the full cost in relation thereto.
         Professor Latchman further agrees that he irrevocably designates and
         appoints each director of the Company other than Professor Latchman as
         the agent and attorney-in-fact of him to do such acts and things and
         execute all such deeds and documents as the Company may deem necessary
         or desirable in order to protect its rights and interest in any such
         Know How, Material or Document.

9.5      Professor Latchman hereby expressly acknowledges that the Company is
         under no duty or obligation under the terms of this Agreement to file,
         prosecute, maintain or renew any Patent Rights where the Company's
         considerations, objectives or priorities from time to time do not
         support such action in any particular country.

9.6      References to the Company in this Clause 9 will be deemed to include
         any or, where indicated by the context, all of the Group Companies.

                                      -7-
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10.      INCAPACITY

10.1     If Professor Latchman is unable to perform the Services because of
         illness or personal injury ("Incapacity"), he must report that fact
         immediately to the Chief Executive or the Chairman of the Company and,
         after three months of such inability, the obligations to make payments
         in accordance with Clause 4 will cease unless the Board at its sole
         discretion shall elect to continue with such payment.

11.      TERMINATION OF AGREEMENT

11.1     Without prejudice to any remedy which the Company may have against
         Professor Latchman for breach or non-performance of any of the
         provisions of this Agreement the Company may by written notice to the
         Professor Latchman forthwith terminate this Agreement if Professor
         Latchman:-

         11.1.1   commits any serious breach or is in continuing breach of his
                  obligations under this Agreement or repeatedly breaches such
                  obligations; or

         11.1.2   engages in any conduct which, in the opinion of the Board, is
                  likely to cause his continued engagement to be detrimental to
                  the interest of the Company or the Group; or

         11.1.3   is convicted of any criminal offence which is punishable with
                  6 months or more imprisonment (save for motoring offence for
                  which he is not sentenced to a term of immediate or suspended
                  imprisonment); or

         11.1.4   commits any act of dishonesty, whether or not relating to the
                  performance of the Services; or

         11.1.5   becomes bankrupt or makes any arrangement or composition with
                  his creditors generally; or

         11.1.6   is, in the reasonable opinion of the board, incompetent in the
                  performance of the Services or is likely to bring the
                  reputation of the Company into disrepute.

         Tax Liabilities

11.2     It is hereby declared that it is the intention of the parties that
         Professor Latchman shall have the status of a self employed person and
         shall be responsible for all income tax liabilities and National
         Insurance or similar contributions in respect of his fees and Professor
         Latchman hereby agrees to indemnifying the Company in respect of any
         claims that may be made by the relevant authorities against the Company
         in respect of income tax or National Insurance or similar contributions
         relating to Professor Latchman's services hereunder.

                                      -8-
<PAGE>

         Payment in lieu

11.3     On serving or receiving notice to terminate this Agreement or at any
         time thereafter during the currency of such notice the Company will, at
         its discretion, be entitled to pay Professor Latchman his fee under
         Clause 4.1 in lieu of his remaining entitlement to notice.

         Claims

11.4     Professor Latchman shall have no claim against the Company in respect
         of the termination of this Agreement:

         11.4.1   by reason of the liquidation of the Company for the purpose of
                  amalgamation or reconstruction or as part of any arrangements
                  for the amalgamation or demerger of the undertaking of the
                  Company not involving liquidation provided that Professor
                  Latchman shall have been offered employment with the
                  amalgamated or reconstructed or de-merged company or companies
                  on terms no less favourable to Professor Latchman than under
                  this Agreement; or

         11.4.2   in relation to any provision in any articles of association,
                  agreement or arrangement which has the effect of requiring
                  Professor Latchman to sell or give up any shares, securities,
                  options or rights at any price or which causes any options or
                  other rights granted to Professor Latchman to become
                  prematurely exercisable or lapse.

12.      GENERAL

12.1     This Agreement sets out the entire agreement of the parties in relation
         to the engagement and is in substitution for any previous Agreement
         between Professor Latchman and the Company or any Group Company which
         are deemed to have been terminated by mutual consent.

12.2     No amendment or addition to this Agreement shall be effective unless it
         is in writing and signed by both parties.

12.3     The termination of this Agreement will not affect such of the
         provisions of this Agreement as are expressed to operate or to have
         effect after termination and will be without prejudice to any accrued
         rights or remedies of the parties.

12.4     The validity, construction and interpretation of this Agreement and any
         determination of the performance which it requires shall be governed by
         English law.

12.5     All disputes between the Parties arising under, out of or relating to
         this Agreement or arising out of the circumstances and relationships
         contemplated by this Agreement including disputes relating to the
         validity, construction or interpretation of this Agreement and
         including its formation, validity, binding effect, interpretation,
         performance, breach or termination as well as non-

                                      -9-
<PAGE>

         contractual claims and including disputes relating to pre-contractual
         representations which result in any action or proceeding shall be
         subject to the non-exclusive jurisdiction of the English Courts.

12.6     Any notice to be given by a party under this Agreement must be in
         writing in the English language and must be delivered by hand or sent
         by first class post or facsimile transmission or other means of
         telecommunication in permanent written form (provided that the
         addressee has his or its own facilities for receiving such
         transmissions) to the last known postal address or appropriate
         telecommunication number of the other party. Where notice is given by
         any of the prescribed means, it is deemed to be received when, in the
         ordinary course of that means of transmission, it would be received by
         the addressee. To prove the giving of a notice, it is sufficient to
         show that it has been despatched. A notice has effect from the sooner
         of its actual or deemed receipt by the addressee.

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                                   SCHEDULE 1

                         DEFINITIONS AND INTERPRETATION

1.       In this Agreement the following words and expressions shall have the
         following meanings:

1.1      "AGREEMENT" - this agreement and any and all schedules, appendices and
         other addenda to it as may be varied from time to time in accordance
         with the provisions of this agreement.

1.2      "BOARD" - the board of directors of the Company and includes any
         committee of such board duly authorised to act on its behalf.

1.3      "COMMENCEMENT DATE" - February 1999.

1.4      "CONFIDENTIAL INFORMATION" - Know How, Materials either owned by or
         licensed to the Company or conceived, created or originated by
         Professor Latchman as set out in Clause 11.1 and trade secrets or
         confidential information relating to the business affairs or finances
         of the Group its suppliers, agents, distributors or customers in either
         case including but not confined to the technology

1.5      "CONTROL" - the ownership of more than 50% of the issued share capital
         or the legal power to direct or cause the direction of the general
         management and policies of the Party.

1.6      "FIELD" - the development and application of viral based vectors for
         therapeutic use including the delivery of potentially therapeutic
         genes. For the avoidance of doubt it is acknowledge and agreed that
         potentially therapeutic genes may have therapeutic prophylactic and
         diagnostic uses other than in conjunction with viral based vectors and
         all such other uses are not within the definition of "Field" for the
         purposes of this Agreement.

1.7      "DOCUMENTS" - reports, research notes, charts, graphs, comments,
         computations, analyses, recordings, photographs, paper, notebooks,
         books, files, ledgers, records, tapes, discs, diskettes, CD-ROM,
         computer programs and documents thereof, computer information storage
         means, samples of material, other graphic or written data and any other
         media on which Know How can be permanently stored.

1.8      "GROUP" - means the Company and each Group Company for the time being.

1.9      "GROUP COMPANY" - means any company which for the time being is a
         holding company or a subsidiary company (as defined in section 736 of
         the Companies Act 1985) of the Company or any subsidiary company of
         such holding company.

                                      -11-
<PAGE>

1.10     "KNOW HOW" - unpatented technical and other information which is not in
         the public domain, including ideas, concepts, inventions, discoveries,
         data, formulae, specifications, information relating to Materials,
         procedures for experiments and tests and results of experimentation and
         testing, results of research or development including laboratory
         records clinical trial data, case report forms, data analyses, reports
         or summaries and information contained in submissions to and
         information from ethical committees and regulatory authorities

1.11     "MATERIAL" - documents and any chemical or biological substances
         including any:-

         (a)      organic or inorganic element or compound;

         (b)      nucleotide or nucleotide sequence including DNA and RNA
                  sequences;

         (c)      gene;

         (d)      vector or construct including plasmids, phages or viruses;

         (e)      host organism including bacteria, fungi, algae, protozoa and
                  hybridomas;

         (f)      eukaryotic or prokaryotic cell line or expression system or
                  any development strain or product of that cell line or
                  expression system;

         (g)      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;

         (h)      drug or pro-drug;

         (i)      assay or reagent;

         (j)      or any other genetic or biologic material or micro-organism;

         (k)      multi-cellular plants;

         (l)      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;

         (m)      computer programmes or algorithms.

1.12     "PARTIES" - Neurovex and Professor Latchman.

1.13     "PATENT RIGHTS" - patent applications or patents, author certificates,
         inventor certificates, utility certificates, improvement patents and
         models and certificates of addition and all foreign counterparts of
         them and includes any divisions, renewals, continuations,
         continuations-in-part, extensions, reissues, substitutions,
         confirmations, registrations, revalidation or additions of or to them,
         as well as any supplementary protection certificate in respect of them.

                                      -12-
<PAGE>

2.       In this Agreement:

2.1      unless the context otherwise requires all references to a particular
         Clause, paragraph or Schedule shall be a reference to that Clause,
         paragraph or Schedule in or to this Agreement as the same may be
         amended from time to time pursuant to this Agreement;

2.2      a table of contents and headings are inserted for convenience only and
         shall be ignored in construing this Agreement;

2.3      unless the contrary intention appears words importing the masculine
         gender shall include the feminine and vice versa and words in the
         singular include the plural and vice versa;

2.4      unless the contrary intention appears words denoting persons shall
         include any individual, partnership, company, corporation, joint
         venture, trust, association, organisation or other entity, in each case
         whether or not having separate legal personality;

2.5      reference to the words "include" or "including" are to be construed
         without limitation to the generality of the preceding words; and

2.6      reference to any statute or regulation includes any modification or
         re-enactment of that statute or regulation.

                                      -13-
<PAGE>

                                   SCHEDULE 2

                              EXISTING COMMITMENTS

EMPLOYMENT

Professor of Molecular Pathology (Established Chair) and Head of Department of
Molecular Pathology (incorporting Medical Molecular Biology Unit and Department
of Chemical Pathology University College London Medical School).

Also, Chairman of Division of Pathology and Infectious Diseases incorporting
Departments of Bacteriology, Immunology, Molecular Pathology, Sexually
Transmitted Diseases and Virology.

Also Director Windeyer Institute of Medical Sciences.

COMMITMENTS EXTERNAL TO UCL

Parkinson's Disease Society Medical Advisory Panel (Vice Chairman)
British Heart Foundation, Project Grants Committee
MRC, Advisory Board
National Institute for Biological Standards, Scientific Advisory Board
Royal College of Pathologists, Examining Panel in Genetics
Scientific Consultant, Biorex Ltd, Hungary
Scientific Advisory Committee, Gene Therapy Centre, Hadassah Hospital, Israel

COMMITMENTS INTERNAL TO UCL

Deputy Head, UCL Graduate School
Chairman Graduate School Graduate Strategy Sub Committee
Chairman Graduate School Life and Clinical Sciences Research Sub-Committee
UCL and Middlesex Hospital Clinical Research and Development Committee (Vice
Chairman)
UCL Academic Committee, Academic Board, Academic Development and Research
Sub-Committee, Research Degrees Sub-Committee, Research Funding Sub-Committee

EDITORIAL BOARDS

Gene Therapy, Gene Therapy and Molecular Biology, Gene Therapy and Regulation,
International Journal of Biochemistry and Cell Biology, International Journal of
Experimental Pathology and Nucleic Acids Research.

Research grant support or research studentships from Government Departments
Research, Councils, Medical Charities and Industry (Glaxo/Wellcome, Smithkline
Beecham, Pfizer).

                                      -14-
<PAGE>

IN WITNESS whereof the parties have executed this document as a deed on the date
appearing at the head of this Agreement.

EXECUTED as a Deed by             ) [ILLEGIBLE]
NEUROVEX LIMITED                  )
acting by                         )
and
                                  [ILLEGIBLE]
                                  Director
                                  Director/Secretary

SIGNED as a Deed by               ) [ILLEGIBLE]
PROFESSOR                         )
DAVID LATCHMAN                    )
in the presence of:-              )

                                  Witness' signature: /s/ [ILLEGIBLE]
                                  Name:
                                  Address: [ILLEGIBLE]
                                  Occupation: [ILLEGIBLE]

                                      -15-

<PAGE>

THIS DEED OF AMENDMENT is made on 30 July 2001

BETWEEN:

(1)      BIOVEX LIMITED (No. 3480520) whose registered office is at The Windeyer
         Institute, 46 Cleveland Street, London W1P 6DB (the "Company")

(2)      PROFESSOR DAVID LATCHMAN of 9 Gresham Gardens, London NW11 8NX
         ("Professor Latchman")

WHEREAS:

(A)      The Company and Professor Latchman entered into an Agreement on 12
         February 1999 (the "Agreement") to engage Professor Latchman to perform
         consultancy services.

(B)      Schedule 2 to the Agreement lists Professor Latchman's Existing
         Commitments and the Company and Professor Latchman now wish to enter
         into this Deed of Amendment in order to amend the Existing Commitments
         as listed in Schedule 2 to the Agreement.

IT IS AGREED as follows:

1.       Schedule 2 to the Agreement be amended by replacing it with Schedule 2
         to this Deed of Amendment.

2.       All other terms of the Agreement remain unchanged.

IN WITNESS of which the parties have executed this instrument as a Deed and have
delivered it upon dating it.

<PAGE>

                                   SCHEDULE 2

                              EXISTING COMMITMENTS

EMPLOYMENT

Dean and Professor of Human Genetics.
Institute of Child Health, University College London.

COMMITMENTS EXTERNAL TO UCL

Parkinson's Disease Society Medical Advisory Panel (Vice-Chairman).
British Heart Foundation, Project Grants Committee.
MRC, Advisory Board.
National Institute for Biological Standards, Scientific Advisory Board.
Royal College of Pathologists, Examining Panel in Genetics.
Scientific Advisory Committee, Gene Therapy Centre, Hadassah Hospital, Israel.
Great Ormond Street Hospital for Children Trust Board.

COMMITMENTS INTERNAL TO UCL

UCL Council.
UCL Biomedicine Strategy Board.
Institute of Child Health Planning and Executive Committee (Chair).
ICH/GOS Joint Research Strategy Committee.

EDITORIAL BOARDS

Gene Therapy, Gene Therapy and Molecular Biology, Gene Therapy and Regulation.
International Journal of Biochemistry and Cell Biology.
International Journal of Experimental Pathology and Nucleic Acids Research.

Research Grant Support of Research Studentships from Government Departments
Research Councils, Medical Charities and Industry (Glaxo/Wellcome, SmithKline
Beecham, Pfizer, Biorex, Hungary).

<PAGE>

SIGNED as a DEED by               )
BIOVEX LIMITED                    )
acting by                         )

                                  Director [ILLEGIBLE]
                                  Director/Secretary [ILLEGIBLE]

SIGNED as a DEED by               )
PROFESSOR DAVID                   )
LATCHMAN                          )
in the presence of:-              )

                                  Witness' signature:

                                  Name:

                                  Address:

                                  Occupation:

<PAGE>

SIGNED as a DEED by               )
BIOVEX LIMITED                    )
acting by                         )

                                  Director
                                  Director/Secretary

SIGNED as a DEED by               )  [ILLEGIBLE]
PROFESSOR DAVID                   )
LATCHMAN                          )
in the presence of:-              )

                                  Witness' signature: /s/ [ILLEGIBLE]

                                  Name: [ILLEGIBLE]

                                  Address: [ILLEGIBLE]

                                  Occupation: [ILLEGIBLE]