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                                                                   EXHIBIT 10.42


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AMENDED.






                                    AGREEMENT



                            DATED 10TH OCTOBER, 2000







                              MEDEVA PHARMA LIMITED



                                       AND



                                AVIRON UK LIMITED



                            FOR THE SALE AND PURCHASE
                         OF LEASEHOLD PROPERTY KNOWN AS
              PLOT 6 BOULEVARD INDUSTRY PARK, HALEWOOD, MERSEYSIDE



<PAGE>   2

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                                TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                             PAGE
                                                                             ----
<S>   <C>                                                                    <C>
1.    INTERPRETATION .......................................................   1

2.    SALE .................................................................   2

3.    SUB-SALES ............................................................   3

4.    TITLE ................................................................   3

5.    COVENANTS, RIGHTS, RENTS AND LEASE OBLIGATIONS .......................   3

6.    VACANT POSSESSION ....................................................   3

7.    CONDITIONAL AGREEMENT ................................................   4

8.    [***] AND GRANTS .....................................................   5

9.    TRANSFER .............................................................   5

10.   COMPLETION ...........................................................   5

11.   STANDARD CONDITIONS OF SALE ..........................................   6

12.   ANNOUNCEMENTS ........................................................   7

13.   [***] ................................................................   8

14.   AGREEMENTS TO BE ASSIGNED ............................................   8

15.   GENERAL ..............................................................   9

16.   NOTICES ..............................................................   9

17.   GOVERNING LAW AND JURISDICTION .......................................  10

18.   EXCLUSION OF THIRD PARTY RIGHTS ......................................  10
</TABLE>


SCHEDULES

1.    Part I The Property

2.    Part I The Covenants

3.    Agreed form of Transfer

4.    Form of Assignment of Agreements

5.    The documents assigned



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THIS AGREEMENT is made on 10th October, 2000

BETWEEN:

(1)     MEDEVA PHARMA LIMITED (registered number 209905) whose registered office
        is at 216 Bath Road, Slough, Berkshire SL1 4EN(the SELLER); and

(2)     AVIRON UK LIMITED whose registered office is at Carmelite, 50 Victoria
        Embankment, London EC4Y ODX (the BUYER).

IT IS AGREED as follows:

1.      INTERPRETATION

1.1     In this agreement:

        "AGREED FORM OF TRANSFER" means the transfer of the Property in the form
        attached to Schedule 3;

        "AGREEMENTS" means the following agreements in respect of the Property:

        (a)     Enhancement Works Agreement dated 7th May, 1999 and made between
                Intercity JIS Limited (1) Medeva Pharma Limited (2) and Medeva
                Plc (3); and

        (b)     Agreement for Underlease dated 7th May, 1999 and made between
                Intercity JIS Limited (1) Medeva Pharma Limited (2) and Medeva
                Plc (3);

        "AGREEMENTS GUARANTOR" means Medeva Limited (formerly known as Medeva
        Plc);

        "ASSIGNMENT OF AGREEMENTS" means the form of deed of assignment of
        agreements attached to Schedule 4;

        "BUYER'S SOLICITORS" means [***];

        "BUYER'S WORKS" means the fitting-out works which the Buyer intends to
        carry out at the Property following completion;

        "CONSENT" means the consent of the Landlord and any Superior Landlord to
        the sale of the Property to the Buyer;

        "CONTRACTOR'S WARRANTY" means the warranty to be given by Sir Robert
        McAlpine Management Contractors Limited;

        "COVENANTS AND RIGHTS" means the covenants and rights referred to in
        Schedule 2;

        "DEPOSIT" means [***];

        "LANDLORD" means the person entitled to the reversion immediately
        expectant on the determination of the term granted by the Lease;


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        "LEASE" means the lease under which the Property is held as specified in
        Schedule 1 and includes every deed varying the Lease and every licence
        granted under the Lease;

        "LEASE OBLIGATIONS" means the covenants by the tenant and the conditions
        contained in the Lease;

        "PROPERTY" means the property specified in Schedule 1;

        "RENTS" means the rents (including further or additional rents) reserved
        by the Lease;

        "SELLER'S GUARANTOR" means the guarantor of the Seller's obligations
        under the Lease;

        "SELLER'S SOLICITORS" means [***];

        "SUPERIOR LANDLORD" means a person entitled to the reversion (whether
        immediate or not) expectant on the determination of the term granted by
        a Superior Lease;

        "SUPERIOR LEASE" means a lease which is superior to or concurrent with
        the Lease;

        "VAT" means value added tax.

1.2     In this agreement:

        (a)     references to a person include a body corporate and an
                unincorporated association of persons;

        (b)     references to a natural person include his estate and personal
                representatives; and

        (c)     subject to clause 15.2 below, references to a party to this
                agreement include references to the successors or assigns
                (immediate or otherwise) of that party.

1.3     Any reference, express or implied, to an enactment includes references
        to:

        (a)     that enactment as amended, extended or applied by or under any
                other enactment (before or after the signature of this
                agreement);

        (b)     any enactment which that enactment re-enacts (with or without
                modification); and

        (c)     any subordinate legislation made (before or after the signature
                of this agreement) under that enactment, as amended, extended or
                applied as described in paragraph (a) above or under any
                enactment referred to in paragraph (b) above.

1.4     Sub-clauses 1.1 to 1.3 above apply unless the contrary intention
        appears.

1.5     The headings in this agreement do not affect its interpretation.

2.      SALE


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2.1     Subject to clause 7 below the Seller agrees to sell and the Buyer agrees
        to buy the Property at the price of [***].

2.2     The Buyer agrees to pay the Deposit to [***] on the date hereof;

2.3     The Seller shall transfer the Property will full title guarantee.

2.4     The transfer shall state that it is subject to every matter subject to
        which the Property is sold by virtue of this agreement.

3.      SUB-SALES

        The Seller shall not be obliged to transfer the Property or any part of
        it to any person other than the Buyer, or at a price divided between
        different parts of the Property or in more than one parcel or by more
        than one transfer.

4.      TITLE

4.1     Office copy entries of the Seller's title are not yet available as the
        Seller's title is in course of first registration. The Seller has
        applied for registration at H.M. Land Registry and the Buyer shall take
        the transfer of the Property on the basis of the pending application.

4.2     The Buyer's solicitors having been provided with copies of:

        (a)     the documents referred to in Schedule 5; and

        (b)     the application for first registration submitted by Messrs [***]
                to H.M. Land Registry and the acknowledgement of that
                application

        the Buyer shall accept that evidence as conclusive evidence of the
        Seller's title to the Property and shall not raise any objection or
        requisition. The Seller shall not be required to give any better title
        to the Property than the Seller has received from the Landlord.

5.      COVENANTS, RIGHTS, RENTS AND LEASE OBLIGATIONS

        The Property is sold subject to the Covenants and Rights, the Rents and
        the Lease Obligations. The Buyer shall [***] in respect of the Covenants
        and Rights, the Rents or the Lease Obligations.

6.      VACANT POSSESSION

        The Property is sold with vacant possession on completion.


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7.      CONDITIONAL AGREEMENT

7.1     This agreement is conditional upon:

        (a)     the obtaining of the Consent;

        (b)     the agreement to be made between the Buyer and Evans Vaccines
                Limited (which agreement the Buyer agrees to use all reasonable
                endeavours to conclude as soon as reasonably practicable after
                the date hereof) relating to the transfer of certain employees
                from Evans Vaccines Limited to the Buyer becoming unconditional
                in all respects; and

        (c)     the Seller obtaining an unconditional release from the Landlord
                of any outstanding obligations on the part of the Seller and the
                Agreements Guarantor under the Agreements.

7.2     The Buyer and the Seller will be jointly responsible for all costs and
        expenses in relation to the obtaining of the Consent and the Buyer will
        be responsible for giving notice of assignment of the Lease.

7.3     The Buyer shall:

        (a)     supply promptly to the Seller such information as may be
                required by the Landlord and any Superior Landlord in connection
                with the application for the Consent;

        (b)     comply with all requirements which, by the terms of the Lease or
                any Superior Lease, the Landlord or any Superior Landlord is
                entitled to impose on a prospective assignee of the Lease as a
                condition of granting the Consent;

        (c)     if required by the Landlord or by any [***] as a condition of
                granting the Consent, [***] with the Landlord to pay the Rents
                and to observe and perform the Lease Obligations and with each
                [***] to observe and perform the covenants on the part of the
                tenant (other than the covenant to [***]) and the conditions
                contained in the relevant [***] Lease; and

        (d)     if required by the Landlord or any [***] as a condition of
                granting the Consent, provide such [***] of the Rents and
                observe and perform the Lease Obligations as the Landlord may
                require (including, without limitation, [***]).

7.4     The Seller shall use all reasonable endeavours to obtain as soon as
        reasonably practicable a release from the Landlord of any of obligations
        on the part of the Seller (and those of the Agreements Guarantor) under
        the Agreements.

7.5     If the conditions set out in sub-clause 7.1 are not satisfied at the end
        of [***] months commencing on the date of this agreement either party
        may thereafter rescind this agreement by notice in writing to the other
        whereupon the Deposit will be returned


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        immediately to the Buyer save to the extent that the Buyer is in breach
        of its obligations hereunder.

7.6     On service of a notice under sub-clause 7.5 neither of the parties shall
        have any further rights or obligations under this agreement except as
        mentioned in sub-clause 7.7.

7.7     Clauses 1, 11, 12, 14, 15, 16 and 18 of this agreement shall remain in
        full force notwithstanding service of notice under sub-clause 7.5.
        Service of that notice shall not affect either party's right in
        connection with any breach of this agreement by the other which may have
        occurred before the notice is served.

7.8     The Buyer may [***] any of the conditions set out in sub-clauses 7.1 (a)
        and/or (b) by written notice to the Seller at any time.

8.      [***] AND GRANTS

8.1     The Seller and the Buyer shall each use reasonable endeavours to obtain
        as soon as possible after the date of this agreement:

        (a)     the consent of the [***] to the [***] in respect of which the
                Buyer shall:

                (i)     supply as soon as reasonably possible to the Seller
                        [***] and such other information as the Landlord may
                        require in connection with the application for consent
                        to the [***];

                (ii)    comply with all reasonable requirements which, by the
                        terms of the Lease, the Landlord is entitled to impose
                        on a prospective tenant of the Property as a condition
                        of granting its consent to the [***]; and

                (iii)   comply with all other reasonable requirements of the
                        Seller and the Landlord in relation to obtaining consent
                        to the [***]; and

        (b)     either:

                (i)     a transfer to the Buyer of the existing Regional
                        Selective Assistance Grant Agreement currently in favour
                        of the Seller; or

                (ii)    a new Regional Selective Assistance Grant in favour of
                        the Buyer for a sum equal to or greater than that
                        currently in favour of the Seller.

9.      TRANSFER

        The transfer to the Buyer shall be in the Agreed Form of Transfer and
        shall be executed in duplicate. The original and the duplicate shall be
        stamped and the duplicates denoted against the original by the Buyer's
        solicitors at the expense of the Buyer. After stamping the Buyer's
        solicitors shall forthwith return the duplicate to the Seller's
        solicitors.

10.     COMPLETION


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10.1    The sale shall be completed at or before 2.00 pm on the Completion Date
        at the offices of the Seller's solicitors or as they may require. The
        Seller shall not be bound to complete otherwise than on a working day
        and otherwise than between 9.30 am and 5.30 pm. Completion shall not be
        delayed if registration of the Seller's title has not been completed on
        the Completion Date.

10.2    In this clause the COMPLETION DATE means the third working day after
        either:

        (a)     the last of the conditions set out in sub-clauses 7.1 is
                satisfied; or

        (b)     the receipt by the Seller of a notice from the Buyer under
                clause 7.8 subject always to the prior satisfaction of the
                condition contained in clause 7.1 (c).

11.     STANDARD CONDITIONS OF SALE

11.1    Subject to the variations mentioned in sub-clause 11.2, the Standard
        Conditions of Sale (Third Edition) (excluding Conditions 1.1.1(a)(ii),
        1.2, 1.3, 1.4, 3.2.2, 3.2.3, 4.2.3, 4.5.2, 4.5.5, 5.1.1, 5.1.2, 5.2.3,
        8.1.3 and 8.3) are incorporated in this agreement so far as they:

        (a)     apply to a sale by private treaty;

        (b)     relate to leasehold property; and

        (c)     are not inconsistent with the other clauses of this agreement.

11.2    The Standard Conditions of Sale (Third Edition) shall be varied as
        follows:

        (a)     add at the end of condition 2.2.1:

                "or by a direct credit to a bank account nominated by the
                seller's solicitor. The deposit shall be paid by a method which
                gives immediately available funds";

        (b)     in condition 3.1.2(d) replace "except those maintained by H.M.
                Land Registry or its Land Charges Department or by Companies
                House" by "except, first, mortgages and, secondly, any entries
                on the register maintained by H.M. Land Registry not disclosed
                by office copy entries supplied before the date of the contract
                by the seller or his solicitors to the buyer or his solicitors";

        (c)     at the end of condition 3.1.2 add new paragraphs (f) and (g) as
                follows:

                "(f)    overriding interests as defined in Land Registration Act
                        1925 Section 70(l) or (where the title to the Property
                        is not registered) matters which would be overriding
                        interests if the title were registered other than (in
                        respect of those parts of the property sold with vacant
                        possession) those referred to in Section 70(l)(g) of
                        that Act;

                (g)     all matters disclosed or reasonably to be expected to be
                        disclosed by searches or as the result of enquiries,
                        formal or informal, and whether


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                        made in person, by writing or orally by or for the buyer
                        or which a prudent buyer ought to make";

        (d)     add the following at the end of condition 5.2.2(f):

                "nor change its use and is to comply with all statutory
                obligations relating to it";

        (e)     replace condition 5.2.7 by the following:

                "The buyer waives the right to raise requisitions or
                observations";

        (f)     replace condition 6.7 by the following:

                "The money due on completion shall be paid by a method which
                gives immediately available funds. If it is not so paid,
                completion is to be treated, for the purposes only of conditions
                6.3 and 7.3, as taking place on the first working day after the
                date of payment when the money due on completion is immediately
                available funds in the hands of the seller";

        (g)     condition 7.1.1 replace "or in the negotiations leading to it"
                by "or in the seller's solicitors' written replies to the
                buyer's solicitors' pre-contract enquiries";

        (h)     condition 7.3 shall be replaced by the following:

                "7.3    LATE COMPLETION

                7.3.1   If there is default by the buyer in performing his
                        obligations under the contract and completion is
                        delayed, the buyer is to [***] to the seller.

                7.3.2   [***] is calculated at the [***] on the [***] less any
                        deposit paid for the period between completion date and
                        actual completion.

                7.3.3   Any claim for loss resulting from [***] is to be reduced
                        by any [***] under this contract.

                7.3.4   Where completion is delayed, the seller may give notice
                        to the buyer, [***] the date of actual completion, that
                        he intends to [***] from the [***] until completion as
                        well as [***] under condition 7.3.1

12.     ANNOUNCEMENTS

12.1    No party shall make, or permit any Associate of his to make any
        announcement concerning the subject matter of this agreement or any
        ancillary matter before, on or after completion except as required by
        law or by the rules of the London Stock Exchange or by any regulatory
        body or without the written approval of the other parties, such approval
        not to be unreasonably withheld or delayed.

12.2    For the purpose of this clause, a body corporate or a partnership is an
        ASSOCIATE of another body corporate or partnership if:


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        (a)     one of them has Control of the other; or

        (b)     the same person or a group of the same (or substantially the
                same) persons has Control of both of them.

12.3    In this clause, CONTROL means:

        (a)     in relation to a body corporate (Company A), the power of a
                person to secure (directly or indirectly):

                (i)     by means of the holding of shares in or the possession
                        of voting power in or in relation to Company A or any
                        other body corporate; or

                (ii)    by virtue of any arrangements, including the
                        constitutional documents of Company A or any other body
                        corporate, that the affairs of Company A are conducted
                        in accordance with the wishes of that person; and

        (b)     in relation to a partnership or other unincorporated
                associations, the right to a share of more than one-half of its
                net assets or net income.

13.     [***]

13.1    If any [***] in respect of any supply made by the Seller under or
        pursuant to this agreement, the [***] shall pay the amount of that [***]
        to the [***] by way of [***] on completion against issue of a [***] by
        the [***].

13.2    Without limiting sub-clause 13.1 above, each amount stated as payable by
        the [***] under or pursuant to this agreement is [***] and is to be
        construed as a reference to that amount plus any [***] in respect of it.

13.3    For the avoidance of doubt, any [***] payable on the Deposit shall be
        paid by the [***] to the [***] when the Deposit is paid.

14.     AGREEMENTS TO BE ASSIGNED

14.1    On actual completion the Seller shall assign to the Buyer (so far as it
        is able to do so but not further or otherwise) the collateral
        warranties, guarantees, covenants and other agreements (the
        "supplemental documents") (if any) detailed in Schedule 4 in the form of
        the Assignment of Agreements but the Seller shall not thereby be treated
        as having given any warranty or assurance that the supplemental
        documents are enforceable.

14.2    As soon as reasonably possible after completion of the Contractor's
        Warranty the Seller shall assign the Contractor's Warranty to the Buyer
        (so far as it is able to do so but not further or otherwise) in the form
        of the Assignment of Agreements (save to the extent that Schedule 2 of
        the form of Assignment of Agreements is amended to refer to the
        Contractor's Warranty alone) but the Seller shall not thereby be treated
        as having given any warranty or assurance that the Contractor's Warranty
        is enforceable.


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15.     GENERAL

15.1    Each of the obligations undertaken by any party under this agreement
        (excluding any obligation fully performed at completion) shall continue
        in force after completion.

15.2    The rights and obligations of the [***] under this agreement may [***].

15.3    Where the Buyer is more than one person:

        (a)     those persons shall be jointly and severally responsible in
                respect of every obligation undertaken by them under this
                agreement; and

        (b)     the Seller may release or compromise the liability of any of
                those persons under this agreement or grant any time or other
                indulgence without affecting the liability of any other of them.

15.4    This agreement may be executed in any number of counterparts, all of
        which, taken together, shall constitute one and the same agreement, and
        any party may enter into this agreement by executing a counterpart.

15.5    This agreement and the documents referred to in it contain the whole
        agreement between the parties relating to the transaction contemplated
        by this agreement and supersede all previous agreements between the
        parties relating to this transaction.

15.6    The Buyer acknowledges that in agreeing to enter into this agreement the
        Buyer has not relied on any representation, warranty, collateral
        contract or other assurance except those set out in this agreement and
        the documents referred to in it and the Seller's solicitors' written
        replies to the Buyer's solicitors' preliminary enquiries. The Buyer
        waives all rights and remedies which, but for this sub-clause, might
        otherwise be available to it in respect of any such representation,
        warranty, collateral contract or other assurance, but nothing in this
        sub-clause shall limit or exclude any liability for fraud.

15.7    For the avoidance of doubt the Buyer shall not acquire any of the
        Seller's liabilities under the Agreements pursuant to the terms of this
        agreement or any ancillary documents.

16.     NOTICES

16.1    Any notice or document to be served under this agreement may be
        delivered or sent by post or facsimile process to the party to be served
        at its address appearing in this agreement as follows:

        (a)     to the Seller at:

                216 Bath Road
                Slough SL1 4EN
                Fax No: 0175 355 1244
                marked for the attention of the Company Secretary


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                and at the Seller's solicitors;

        (b)     to the Buyer at the Buyer's solicitors

        or at such other address or facsimile number as it may have notified to
        the other parties in accordance with this clause. Any notice or other
        document sent by post shall be sent by prepaid first class recorded
        delivery post (if within the United Kingdom) or by prepaid airmail (if
        elsewhere).

16.2    Any notice or document shall be deemed to have been served:

        (a)     if delivered, at the time of delivery; or

        (b)     if posted, at 10.00 am on the second working day after it was
                put into the post, if sent within the United Kingdom, or at
                10.00 am (local time at the place of destination) on the fifth
                working day after it was put into the post, if sent by airmail;
                or

        (c)     if sent by facsimile process, at the end of two hours after the
                time of despatch, if despatched before 3.00 pm (local time at
                the place of destination) on any working day, and in any other
                case at 10.00 am (local time at the place of destination) on the
                next working day after the date of despatch.

16.3    In proving service of a notice or document it shall be enough to prove
        that delivery was made, or that the envelope containing the notice or
        document was properly addressed and posted as a prepaid first class
        recorded delivery letter or that the or facsimile message was properly
        addressed and despatched, as the case may be.

17.     GOVERNING LAW AND JURISDICTION

17.1    This agreement is governed by and shall be construed in accordance with
        English law.

17.2    The Buyer agrees for the exclusive benefit of the Seller that the
        English courts are to have jurisdiction to settle any disputes which may
        arise in connection with this agreement and that any proceedings arising
        in connection with this agreement may be brought in those courts. The
        Buyer irrevocably appoints the Buyer's solicitor as its agent for
        service of process. Nothing in this clause limits any right to take
        proceedings against the Buyer in any other court of competent
        jurisdiction nor shall the taking of proceedings in one or more
        jurisdictions preclude the taking of proceedings in any other
        jurisdiction, whether concurrently or not.

18.     EXCLUSION OF THIRD PARTY RIGHTS

        A person who is not a party to this agreement may not enforce any of its
        terms under the Contracts (Rights of Third Parties) Act 1999.

AS WITNESS the hands of the parties on the date which appears first on page 1.


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COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.



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                                   SCHEDULE 1

                                  THE PROPERTY



All that property known as Plot 6, Boulevard Industry Park, Halewood, Merseyside
comprised in a sub-underlease dated 17th February, 2000 made between MEPC
Boulevard Limited (1), Medeva Pharma Limited (2) and Medeva plc (3) in the
course of first registration at Birkenhead District Land Registry under
reference MS429644/DFL/008










[***] - CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
[***] HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.


                                    Sch. 1-1
<PAGE>   14

                                   SCHEDULE 2

                            THE COVENANTS AND RIGHTS



All matters contained or referred to in the Lease.










[***] - CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
[***] HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.


                                    Sch. 2-1
<PAGE>   15

                                   SCHEDULE 3

                             AGREED FORM OF TRANSFER












[***] - CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
[***] HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.



                                    Sch. 3-1
<PAGE>   16

                                   SCHEDULE 4



                             DATED ____________ 2000





                              MEDEVA PHARMA LIMITED



                                       TO



                                AVIRON UK LIMITED





                      -------------------------------------

                        DEED OF ASSIGNMENT OF AGREEMENTS

                                   RELATING TO

                      AGREEMENTS IN CONNECTION WITH PLOT 6,
                         BOULEVARD INDUSTRY PARK, SPEKE,
                              HALEWOOD, MERSEYSIDE

                      -------------------------------------









[***] - CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
[***] HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.
<PAGE>   17
DEED OF ASSIGNMENT

DATED: ________________________ 2000

PARTIES:

1.      MEDEVA PHARMA LIMITED (registered number 209905) whose registered office
        is at 216 Bath Road, Slough, Berkshire SLI 4EN (the "Assignor"); and

2.      AVIRON UK LIMITED whose registered office is at Carmelite, 50 Victoria
        Embankment, London EC4Y ODX (the "Assignee").

1.      RECITAL

        By a transfer of even date hereto the Assignor completed the sale to the
        Assignee of the property briefly described in Schedule 1.

2.      ASSIGNMENT

        Pursuant to the sale the Assignor assigns to the Assignee so far as it
        is lawfully able to do so the benefit (if any) of the document or
        documents brief particulars of which are contained in Schedule 2.

IN WITNESS of which this Assignment has been executed as a deed and has been
delivered on the date which appears first above.

                                   SCHEDULE 1

                                  THE PROPERTY

All that property known as Plot 6, Boulevard Industry Park, Halewood, Speke,
Merseyside comprised in a sub-underlease dated 17th February, 2000 made between
MEPC Boulevard Limited (1), Medeva Pharma Limited and Medeva plc (3) in the
course of first registration at Birkenhead District Land Registry under
reference MS429644/DFL/008.

                                   SCHEDULE 2

                          THE DOCUMENTS TO BE ASSIGNED



<TABLE>
<CAPTION>
               DATE                  DOCUMENT                         PARTIES
<S>         <C>                   <C>                              <C>
[1.         ***                   ***                              ***
2.          ***                   ***                              ***
3.          ***                   ***                              ***
</TABLE>


[***] - CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
[***] HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.


                                    Sch. 4-2
<PAGE>   18

<TABLE>
<CAPTION>
               DATE                  DOCUMENT                         PARTIES
<S>         <C>                   <C>                              <C>

4.          ***                   ***                              ***
5.          ***                   ***                              ***
6.          ***                   ***                              ***
7.          ***                   ***                              ***
8.          ***                   ***                              ***
9.          ***                   ***                              ***
10.         ***                   ***                              ***]
</TABLE>



The Common Seal of            )
MEDEVA PHARMA                 )
LIMITED was affixed to this   )
Deed in the presence of:      )


                                       -----------------------------------------
                                       Director



                                       -----------------------------------------
                                       Director/Secretary





[***] - CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
[***] HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.



                                    Sch. 4-3
<PAGE>   19

                                   SCHEDULE 5

                             THE DOCUMENTS SUPPLIED

[***.]

[***]

[***]








[***] - CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
[***] HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.



                                    Sch. 5-1
<PAGE>   20

Signed by MARK GLYN HARDY  )           /s/ S. McGarrity
for the Seller in the      )
presence of.               )





Signed by                  )           /s/ Fred Kurland
for the Buyer in the       )
presence of                )









[***] - CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
[***] HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE
COMMISSION PURSUANT TO RULE 24B-2 OF THE SECURITIES EXCHANGE ACT OF 1934, AS
AMENDED.