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                                                                    EXHIBIT 10.1

                     BIOREX KUTATO ES FEJLESZTO RT. ("V.A.")

                    BRX RESEARCH AND DEVELOPMENT COMPANY LTD

                                       and

                                CYTRX CORPORATION

                        ASSET SALE AND PURCHASE AGREEMENT

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                        ASSET SALE AND PURCHASE AGREEMENT

      THIS AGREEMENT is made as of the 4th day of October, 2004

      BETWEEN:

(1)   BIOREX KUTATO ES FEJLESZTO RT. ("V.A.") (Company number 01-10-041448)
      whose registered office is at 1065 Budapest, Bajcsy-Zsilinszky ut 37 (the
      "Seller");

(2)   BRX RESEARCH AND DEVELOPMENT COMPANY LTD whose registered office is at 200
      Aldersgate Street, London EC1A 4JJ, UK (the "Shareholder"); and

(3)   CYTRX CORPORATION, a Delaware corporation with a principal address of
      11726 San Vicente Blvd. Suite 650 Los Angeles, California 90049 (USA) (the
      "Purchaser" and, jointly with the Seller and the Shareholder, the
      "Parties").

      RECITALS:

      The Seller has agreed to sell the Assets (as defined below), the Purchaser
has agreed to purchase the Assets (as defined below) and Shareholder has agreed
to the obligations contained herein all on and subject to the terms of this
Agreement.

      IT IS AGREED:

1.    DEFINITIONS

            In this Agreement:

1.1   except where the context otherwise requires the following words and
      expressions shall have the following meanings:

            "ASSETS" means the Patents and Patent Applications, inventory of
      manufactured lead compounds, physical library of compounds, detailed
      patient databases, submissions to regulatory

                                      C-1
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      authorities, correspondence and/or documents to and from regulatory
      authorities, correspondence and/or documents with any third party related
      to the process development or manufacture of all products and/or
      intermediates, scientific data derived from mechanism of action studies
      and archives of study reports including clinical, pharmacology,
      toxicology, biology and chemistry studies, the notebooks used during the
      research leading up to the Patent applications and the Patent Applications
      and all other documentation related to the research, Patents, the Patent
      Applications and the compounds being the subject thereof as listed in
      Schedule A to this Agreement and the corporate name "Biorex Kutato es
      Fejleszto Rt." and the Seller's trademarks.

            "BILL OF SALE" means the bill of sale in substantially the format as
      set out at Schedule B to this Agreement;

            "BUSINESS DAY" means a day which is not a Saturday, Sunday or an
      official bank holiday both in California, USA and Budapest, Hungary;

            "CLOSING" means completion of this Agreement, including the issuance
      by the Seller of an irrevocable wire transfer (and the delivery to the
      Seller of the indentification number of the wire transfer) for the
      Purchase Payment, in accordance with its terms;

            "CLOSING DATE" means any date on or before October 8, 2004, on which
      the Closing occurs,

            "ENCUMBRANCES" means any and all liens, charges, security interests,
      options, adverse claims, litigation, mortgages, pledges, understandings or
      arrangements or other restrictions on title or transfer of any nature
      whatsoever;

            "INVENTIONS" means the inventions that are the subject matter of the
      Patent Applications;

            "PATENT APPLICATIONS" means the applications for patents set out in
      Schedule A to this Agreement and each and any of them, which applications
      constitute all applications for patents filed by the Seller;

            "PATENTS" means the issued patents set out in Schedule A to this
      Agreement and each and any of them, which patents constitute all patents
      owned by the Seller;

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            "RIGHTS" means all the rights, titles, interests and other matters
      assigned or purported to be assigned pursuant to Section 2;

            "THIRD PARTY" means a person other than a party to this Agreement;
      and

            "WARRANTIES" means the warranties of the Parties set out at Section
      4 and all statements contained in any schedule hereto.

1.2   the singular includes the plural and vice versa.

2.    THE CLOSING, SALE AND PURCHASE

2.1   The Closing of this Agreement shall take place on the Closing Date at the
      offices of Gide Loyrette Nouel/Gaal, Molnar & Ferenczy Ugyvedi Iroda in
      Budapest, Hungary.

2.2   On the Closing, subject to the terms and conditions of this Agreement, (i)
      the Purchaser shall pay to the Seller consideration of three million U.S.
      dollars (3,000,000 USD) (the "Purchase Payment") by initiating an
      irrevocable bank transfer to the bank account of the Seller (account no.
      Bank: Deutsche Bank Rt Bank; Address: Hold u. 27., H-1054 Budapest,
      Hungary; Account: Biorex Research and Development Co. Rt.; Account No:
      16300000-04005518-00040014 (USD); Swift Code: DEUTHU2B IBAN:HU64 1630 0000
      0400 5518 0004 0014) or as otherwise agreed by the Parties and (ii) in
      consideration of the Purchase Payment and upon and subject to the receipt
      of such amount as cleared funds on the above bank account, the Seller
      shall on the Closing Date sell, convey, assign, transfer and deliver
      automatically without any need to take any further steps on the Closing to
      the Purchaser all of the Assets, which shall be free and clear of any
      Encumbrance (other than as disclosed in any of the Schedules to this
      Agreement):

            The conveyance of the Assets shall include as to the Rights the
      following:

      (a)   the Patents, all the right, title and interest therein and all the
            rights, powers, privileges and immunities conferred on the
            proprietor thereof by the grant of the Patents;

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      (b)   the Patent Applications, all the right, title and interest therein
            and all the rights, powers, privileges and immunities arising or
            accrued therefrom with the intent and to the extent that the grant
            of patents pursuant to the Patent Applications shall be in the name
            of and shall vest in the Purchaser;

      (c)   the right to sue for damages and other remedies in respect of any
            infringement of the Patents before as well as after the date of this
            Agreement (with any such incidents of infringement of any Patent
            known to the Seller on the date hereof as set out in Schedule C to
            this Agreement) and the right to sue for damages and other remedies
            in respect of any acts carried out by another person within the
            scope of the claims of any published specification of the Patent
            Applications before as well as after the date of this Agreement,
            together with all consulting or other agreements relating to such
            claims (with any such agreements being set forth in Schedule A to
            this Agreement);

      (d)   all of the Seller's rights to apply for, prosecute, obtain patents,
            and claim priority from (i) Patent Applications listed in Schedule A
            and any applications based thereon or claiming priority thereto;
            (ii) any patents issued from any such applications described in (i)
            above anywhere in the world; (iii) any divisions, registrations,
            confirmations, reissues, re-examinations, extensions, renewals,
            continuations, continuations-in-part, revalidations, additions,
            substitutions or renewals entitled to claim priority to any such
            patent applications or patents described in (i); and (iv) all
            national, regional and foreign counterparts or other forms of
            protection, including supplementary protection certificates,
            directed to the inventions covered by the Patents or Patent
            Applications listed in Schedule A;

      (e)   all other Assets not specifically listed in Section 2.2(a) through
            (d) above, as listed in Schedule A to this Agreement.

      If requested by the Purchaser, the Seller agrees to hold at its facilities
      the documents and all other tangible materials included in the Assets for
      the account of the Purchaser for a period of thirty days after the Closing
      Date at no additional charge to the

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      Purchaser. The Purchaser shall have full access to such materials in the
      Seller's possession, and the Seller shall deliver such materials to the
      Purchaser or its designee when requested by the Purchaser. All costs of
      moving the materials from the Seller's facilities, including all shipping
      and packaging costs, will be borne by the Purchaser.

2.3   MILESTONE PAYMENTS

      (a)   Subject to Sections 2.3(c) and 2.3(e) below, after the Closing, the
            Purchaser shall make the following cash payments to the Seller, or
            its designee(s), as additional consideration for the Assets:

            (i)   Five hundred thousand U.S. dollars (500,000 USD) within 30
                  days following the filing by the Purchaser (or any of its
                  affiliates) of each investigational new drug application (IND)
                  with the U.S. Food and Drug Administration ("FDA") or the
                  equivalent regulatory agency of any other country for any
                  product that could not be commercialized without using or
                  infringing any of the Patents or Patent Applications;
                  provided, however, that the amount of the first payment made
                  pursuant to this Section 2.3(a)(i) (but not any subsequent
                  payments pursuant to this subsection), if any such payment
                  becomes payable, shall be increased by 10% per year (and a pro
                  rata portion of such 10% for any partial year) after the
                  second anniversary of this Agreement.

            (ii)  One million U.S. dollars (1,000,000 USD) within 30 days
                  following the commencement of each Phase III trial by the
                  Purchaser (or any of its affiliates) that is approved by the
                  FDA or the equivalent agency of any other country for any
                  product that could not be commercialized without using or
                  infringing any of the Patents or Patent Applications.

            (iii) Two million six hundred fifty thousand U.S. dollars (2,650,000
                  USD) within 30 days following the receipt by the Purchaser (or
                  any of its affiliates) from the FDA or the equivalent
                  regulatory agency of any other country of each marketing
                  approval for any new drug application (NDA)

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                  for any product that could not be commercialized without using
                  or infringing any of the Patents or Patent Applications.

      (b)   Subject to Section 2.3(c) below, in the event that the Purchaser (or
            any of its affiliates) licenses any Patent or Patent Application to
            any third party that is not an affiliate of the Purchaser, the
            Purchaser (or such affiliate) shall remit to Seller, or its
            designee(s), any milestone payments received by the Purchaser in
            respect of such Patents or Patent Applications within 30 days
            following receipt thereof.

      (c)   The aggregate payments under Section 2.3(a) and 2.3(b) shall in no
            event exceed four million one hundred fifty thousand U.S. dollars
            (4,150,000 USD). If the Purchaser has paid such amount in the
            aggregate pursuant to Sections 2.3(a) and 2.3(b), the parties
            acknowledge and agree that the Purchaser shall have no obligation to
            make any further payments pursuant to those Sections.

      (d)   For the avoidance of doubt, the parties acknowledge and agree that
            no purchaser or licensee of any Asset shall have any obligation to
            make any payments pursuant to Sections 2.3(a) or 2.3(b), and the
            Purchaser shall have no obligation to make any payments as a result
            of any actions taken by or approvals received by any such purchaser
            or licensee except as expressly set forth in this Agreement.

      (e)   If the Purchaser has already made a payment pursuant to Section
            2.3(a) with respect to a filing, commencement of a clinical trial or
            receipt of regulatory approval in a particular jurisdiction, no
            further payment shall be required by Section 2.3(a) in connection
            with a substantially similar filing, commencement of a clinical
            trial or receipt of regulatory approval in another jurisdiction for
            the same product.

2.4   SALES OF ASSETS

      (a)   Subject to the provisions of this Section 2.4 (b) in the event that
            the Purchaser (or any of its affilates) sells any Assets to a third
            party that is not an affiliate of the Purchaser (an "Asset Sale"),
            the Purchaser (or the applicable affiliate) shall make the following
            cash payments to the Seller, or its designee(s):

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            (i)   Within 30 days of the consummation of any such Asset Sale, an
                  amount equal to 15% of the difference, if a positive number,
                  between (x) the aggregate Net Proceeds of such Asset Sale and
                  any prior Asset Sale(s), minus (y) the sum of (i) the amount
                  of the Purchase Payment plus (ii) the aggregate amount of all
                  payments actually made by the Purchaser pursuant to Section
                  2.3(a) and 2.3(b). Only one payment shall be made pursuant to
                  this Section 2.4(a)(i).

            (ii)  If any payment has been made pursuant to Section 2.4(a)(i),
                  within 30 days of the consummation of any Asset Sale
                  subsequent to such payment, an amount equal to 15% of the
                  difference, if a positive number, between (x) the Net Proceeds
                  of such Asset Sale, minus (y) the aggregate amount of any
                  payments actually made by the Purchaser pursuant to Sections
                  2.3(a) and 2.3(b) since the date of the latest payment made by
                  the Purchaser pursuant to either Section 2.4(a)(i) or
                  2.4(a)(ii).

      (b)   If the Purchaser has paid four million one hundred fifty thousand
            U.S. dollars (4,150,000 USD) in the aggregate pursuant to Sections
            2.3(a) and 2.3(b), the parties acknowledge and agree that the
            Purchaser shall have no obligation to make any further payments
            pursuant to this Section 2.4.

      (c)   Notwithstanding anything to the contrary herein, the term "Asset
            Sale" shall not include a sale of all or substantially all of the
            assets of the Purchaser if this Agreement is assumed in its entirety
            by the purchaser of those assets.

      (d)   For purposes of this Section 2.4, "Net Proceeds" shall mean the cash
            sale proceeds actually received by the Purchaser in connection with
            an Asset Sale, less documented transaction costs and expenses
            incurred with such Asset Sale (including attorney's fees and
            investment banking fees). In the event that an Asset Sale also
            includes the sale of assets that were not purchased pursuant to this
            Agreement, then the Net Proceeds of such Asset Sale for purposes of
            this Section 2.4 shall be the portion of the cash sale proceeds
            allocated by the Purchaser to the portion of the sold assets that
            constitute Assets hereunder, less

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            a pro rata portion of the documented transaction costs and expenses.
            Such allocation will be made by the Purchaser in good faith based on
            its estimate of the fair market value of the sold assets. The
            Purchaser shall notify the Seller, or its designee, of such
            allocation promptly following consummation of any such Asset Sale.
            If the Seller, or its designee, disagrees with such allocation:

            (i)   Seller, or its designee, shall promptly, but in no event later
                  than 10 business days following receipt of the notice of
                  allocation from the Purchaser, send a written notice (a
                  "Dispute Notice") to the Purchaser setting forth in reasonable
                  detail the basis for the dispute. If no such notice is
                  received by the Purchaser within such 10 business day period,
                  then the allocation of proceeds determined by the Purchaser
                  shall be deemed to have been accepted by the Seller, and shall
                  become final and binding upon the parties hereto for purposes
                  of calculating amounts payable pursuant to Section 2.4.

            (ii)  Upon delivery of any Dispute Notice, the Seller (or its
                  designee) and the Purchaser shall submit to an Independent
                  Accounting Firm (as defined below) for a determination of the
                  proper allocation of the proceeds of the Asset Sale, based on
                  the fair market value of the sold assets. The determination of
                  the Independent Accounting Firm shall be binding on the
                  parties hereto for purposes of calculating amounts payable
                  pursuant to Section 2.4.

            (iii) "Independent Accounting Firm" means (i) an independent
                  certified public accounting firm in the United States or in
                  the United Kingdom of national recognition mutually acceptable
                  to Seller and Purchaser or (ii) if Seller and Purchaser are
                  unable to agree upon such a firm within five (5) days, then
                  each party shall select one such firm and those two firms
                  shall select a third firm, in which case "Independent
                  Accounting Firm" shall mean such third firm.

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            (iv)  The cost of the Independent Accounting Firm's review and
                  determination shall be paid by the Seller, or its designee.

2.5   The corporate name, "Biorex Kutato es Fejleszto" and the Biorex trademark,
      as items within the definition of the Assets, shall be transferred to the
      Purchaser by the end of the Warranty Period (as defined at section 5.2
      below).

2.6   Between the signing of this Agreement and the Closing, neither the Seller
      nor the Shareholder shall engage in any discussions with any Third Party
      concerning the sale or other disposition of any of the Assets or take any
      other action inconsistent with completing the sale of the Assets to the
      Purchaser. The Seller shall advise the Purchaser of any communications
      that it has with any Third Party with respect to the foregoing during this
      period.

2.7   All revenues or income and expense or liabilities in relation to the
      Assets, including maintenance costs of the Patents and Patent Applications
      (which are recurring or periodic in nature), shall be allocated between
      the Purchaser and the Seller as of the Closing Date, such that the Seller
      is entitled to the revenues or income and responsible for the expenses and
      liabilities relating to the period ending on the Closing Date, and the
      Purchaser is entitled to the revenues or income and responsible for the
      expenses and liabilities relating to the period commencing after the
      Closing Date. The Parties agree that there is no revenue or income that
      has accrued with respect to any of the Assets through the Closing Date
      that will be allocated to the Seller and that all income generated after
      the Closing Date through the use or sale of any of the Assets will be the
      sole property of the Purchaser.

2.8   Following the end of the Warranty Period (as defined at section 5.2
      below), the Purchaser or any of its affiliates shall have the sole and
      exclusive right to use the name "Biorex Kutato es Fejleszto" or any
      similar name that includes the term "Biorex".

2.9   The Purchaser shall not assume any of the existing debts of the Seller or
      any other liabilities of the Seller relating to the Assets that have
      accrued through the Closing Date,

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      all of which shall remain the obligation of the Seller and shall be paid
      or otherwise discharged in full by the Seller.

2.10  The Parties shall, at Purchaser's cost and risk, within a reasonable
      period of time after the Closing Date, make arrangements for the shipping,
      storage or disposal (upon written instructions from the Purchaser and at
      Purchaser's cost) of the Assets and the Purchaser shall bear all costs and
      risks to the Assets following the Closing Date.

2.11  The Seller will provide the Purchaser with audited financial statements
      covering the Assets for the time period through the Closing Date if such
      financials have already been prepared or will provide all reasonable
      assistance required by the Purchaser after the Closing in preparing such
      financial statements if the Purchaser determines that such financial
      statements are required under the U.S. securities laws.

2.12  If the Closing has not occurred on or before October 8th, 2004 because the
      Purchaser has failed to pay the Purchase Payment, this Agreement shall
      automatically terminate and become null and void. If this Agreement
      terminates because the Purchaser has failed to pay the Purchase Payment,
      the Purchaser agrees to reimburse the Seller for all actual third party
      out-of-pocket expenses (up to a maximum of USD 75,000) incurred by the
      Seller in connection with this Agreement during the 30 days prior to the
      date of this Agreement. Such payment shall be made upon the receipt by the
      Purchaser of an invoice setting forth such expenses in reasonable detail.

3.    FURTHER ASSURANCE

      At any time prior to the completion of the dissolution of the Seller; the
      Seller shall at the request and expense of the Purchaser do all acts and
      execute, file and/or register all documents that are reasonably necessary
      or desirable to vest absolute legal and beneficial ownership of the Rights
      in the Purchaser (or the Purchaser's nominee) or to perfect the
      Purchaser's (or the Purchaser's nominee's) title to the Rights anywhere in
      the world.

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4.    WARRANTIES

4.1   The Seller warrants at the Closing Date, with reference to the facts then
      existing, that:

      (a)   the Seller is a corporation duly organized, validly existing and in
            good standing under the laws of Hungary, with full corporate power
            and authority to conduct its business as it is now conducted;

      (b)   the Seller is and will remain solvent at all times until the
            completion of its dissolution; the Seller's assets are and will
            remain sufficient for the covering of its contractual and statutory
            obligations so that its final settlement will not be terminated by
            any governmental authority or court and no statutory liquidation
            could be instituted by any governmental authority or court after the
            date of this Agreement; and the Seller has not committed and will
            not commit any action during its final settlement which, in the case
            of a statutory liquidation of the Seller as the case may be pursuant
            to the previous clause, might result in the liquidator challenging
            the transactions entered into by the Seller during its solvent
            liquidation;

      (c)   the Seller (i) has good, valid and marketable title to all of the
            Assets, (ii) is the sole beneficial and, where applicable, record
            owner of such Assets and (iii) shall transfer the Assets to the
            Purchaser free and clear of all Encumbrances;

      (d)   the Seller has full power to enter into this Agreement and the
            execution and performance of this Agreement and any agreements
            ancillary to this Agreement will not violate the terms of any
            material agreement with any Third Party, any material law or
            regulation applicable to the Seller or the Assets or any of the
            Seller's constitutional documents;

      (e)   the Seller has obtained all necessary consents and approvals to
            enable it to enter and perform this Agreement, and, based on the
            Purchaser's representations set forth at Section 4.3(d) below, no
            consent of the Hungarian Competition Office is required for the
            Closing of this Agreement;

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      (f)   the performance by the Seller of its obligations under this
            Agreement constitute valid and legally binding obligations and the
            Agreement is enforceable against the Seller in accordance with its
            terms;

      (g)   the Seller is properly registered as the owner of the Patents and as
            the applicant for the Patent Applications and all renewal and other
            fees due in respect of the Patents and Patent Applications have been
            paid when due;

      (h)   the materials and samples listed in Schedule A to this Agreement
            have expiry dates as set out next to each material and sample in
            Schedule A to this Agreement and the Seller has no reason to believe
            that such materials and samples are not in good and useable
            condition;

      (i)   preclinical and clinical documents listed in Schedule A to this
            Agreement have been prepared in accordance with applicable
            regulatory requirements in all material respects;

      (j)   to the best of the Seller's knowledge, the assets referred to in
            Section 2.2(e) include all documentation related to the Patents, the
            Patent Applications and the compounds that are the subject thereof,
            and no further Assets need to be transferred to Purchaser in order
            for the Purchaser to enjoy the full benefit of the Patents and
            Patent Applications to the same extent that it is enjoyed by the
            Seller as of the date of this Agreement; and, except as disclosed in
            Schedule A, the Seller has not granted to any Third Party any
            license to any Patent or Patent Application;

      (k)   other than as disclosed in Schedule C to this Agreement, the Seller
            has not received any notice of infringement from any third party or
            any notice challenging the validity or ownership of the Patents or
            Patent Applications nor does the Seller or the Seller's management
            have any knowledge of any such infringement or challenge as to
            validity or ownership relating to any of the Patents or Patent
            Applications;

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      (l)   each of the Schedules to this Agreement contain true, accurate and
            complete descriptions of the matters therein described or listed;

      (m)   the Seller has no employees and the sale, transfer and delivery by
            the Seller of the assets listed in Section 2.2 to the Purchaser
            shall not make the Purchaser the legal successor to the Seller
            pursuant to Hungarian labor law.

4.2   The Shareholder warrants at the Closing Date, with reference to the facts
      then existing, that:

      (a)   it is a corporation duly organized, validly existing and in good
            standing under the laws of England, with full power and authority to
            conduct its business as it is now conducted;

      (b)   it is and will remain solvent at all times until the completion of
            its dissolution (for the purposes of this warranty, all debts of the
            Shareholder owed to the Seller are disregarded);

      (c)   it has full power to enter into this Agreement;

      (d)   it has obtained all necessary consents and approvals to enable it to
            enter and perform the Agreement;

      (e)   the performance of its obligations under the Agreement constitute
            valid and legally binding obligations and the Agreement is
            enforceable against the Seller in accordance with its terms;

      (f)   other than as disclosed in Schedule C to this Agreement, it has not
            received any notice of infringement from any third party or any
            notice challenging the validity or ownership of the Patents or
            Patent Applications nor does it or any member of Shareholder's
            management have any knowledge of any such infringement or challenge
            as to validity or ownership relating to any of the Patents or Patent
            Applications.

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4.3   The Purchaser warrants at the date of this Agreement, with reference to
      the facts then existing, that

      (a)   the Purchaser is a corporation duly organized, validly existing and
            in good standing under the laws of the State of Delaware, with full
            corporate power and authority to conduct its business as it is now
            conducted;

      (b)   the Purchaser has full power and authority to enter into this
            Agreement;

      (c)   the Purchaser has obtained all necessary consents and approvals to
            enable it to enter and perform the Agreement;

      (d)   the Purchaser did not generate any turnover on its own or through
            its subsidiaries, directly or indirectly affiliated companies or
            branches in 2003 which would qualify as relevant turnover for
            Hungarian merger clearance purposes;

      (e)   the Purchaser has not made, nor is it obligated to make any payment
            to any party related to the Seller or the Shareholder in connection
            with this Agreement, other than under Section 2.12;

      (f)   the performance by the Purchaser of its obligations under the
            Agreement constitute valid and legally binding obligations and the
            Agreement is enforceable against the Purchaser in accordance with
            its terms;

      THE WARRANTIES IN THIS ARTICLE 4 ARE IN LIEU OF AND EXCLUDE ALL OTHER
WARRANTIES, EXPRESS OR IMPLIED, ORAL OR WRITTEN, INCLUDING WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

5.    LIMITATION OF LIABILITY

5.1   Subject to the provisions of this Agreement, Seller and Shareholder each
      shall jointly and severally indemnify, defend and hold harmless the
      Purchaser, its officers, agents, servants

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      and employees against any loss, claim, liabilities, obligations, demands,
      cause of action or proceedings, interest or penalties recovered by third
      parties, costs and expenses (including reasonable attorneys' fees incurred
      in defense of any of the same or in asserting, preserving or enforcing any
      of the Rights of the Purchaser (or its nominee) arising under this
      Agreement), arising from any breach or non-fulfilment of the Warranties of
      the Seller or Shareholder or any agreement of the Seller hereunder. The
      total joint amount of the liability of the Seller and Shareholder in
      respect of any breach or non-fulfilment of the Warranties hereunder shall
      be limited to and in no event exceed in the aggregate three million U.S.
      dollars (3,000,000 USD), plus all of the amounts, if any, paid prior to
      expiration of the Warranty Period or subsequently payable to the Seller
      pursuant to Section 2.3. In the event of breach of one of the Seller's or
      Shareholder's Warranties which relate to an Asset described in the Bill of
      Sale, liability to Purchaser with respect to such breach shall be limited
      to an amount equal to the sum of (a) the portion of the Purchase Payment
      amount attributed to such Asset on the Bill of Sale, plus (b) any amount
      payable pursuant to Section 2.3 attributed to such Asset. The parties
      agree that the Purchaser may, at its option, offset any amounts owing to
      it pursuant to this Section 5.1 against any amounts that it owes pursuant
      to Section 2.3.

5.2   The Seller and Shareholder shall be under no liability whatsoever in
      respect of any breach or non-fulfilment of any of the Warranties of the
      Seller and/or Shareholder hereunder unless the Purchaser has served on the
      Seller a written notice within three (3) months following the Closing (the
      "Warranty Period") giving reasonable details of the claim. The Seller
      agrees that it will not complete its voluntary dissolution and will not
      cease to exist prior to the expiration of this three-month notice period.

5.3   The Purchaser shall give the Seller prompt notice of any third-party claim
      that may give rise to any indemnification obligation under this Article 5.
      The Seller shall, and shall cause its affiliates to, cooperate in the
      defense or prosecution thereof, which cooperation shall include the
      retention, and the provision to the Purchaser, of records and information
      reasonably relevant to such third-party claim.

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5.4   If the Seller pays any sum to the Purchaser pursuant to a claim made for
      breach of any of the Warranties, the amount of the Purchase Payment paid
      by the Purchaser to the Seller for the Assets shall be deemed to be
      reduced by the amount of any such payment.

5.5   To the extent that any breach of the Warranties is capable of remedy, and
      where it is within its power to do so, the Purchaser shall afford the
      Seller a reasonable opportunity to remedy the matter complained of.

5.6   The Seller shall not be liable for any claim arising, or for any increased
      liabilities, as a result of the passing of any enactment or other measure
      having the force of law or a change in administrative practise which takes
      place after the Closing even if such change has retrospective effect,
      unless the Seller was aware of such measure and did not take reasonable
      steps to mitigate the effects of such measure on the Seller or the Assets.

5.7   For the sake of convenience and for ease of reference only, matters
      disclosed in the Schedules to this Agreement are listed against numbers
      contained in the Agreement to which the disclosure may be most likely to
      relate but the contents of each Schedule and of all documents and papers
      referred to therein shall be deemed to have been disclosed in relation to
      every provision of the Agreement to which they may relate, and each
      disclosure is given without prejudice to the generality and effectiveness
      of each of the other disclosures.

6.    GOVERNING LAW

      This Agreement and the jurisdiction clause contained in it shall be
      governed by, construed in accordance with the laws of the State of
      California, U.S.A. without giving effect to the principles of conflicts of
      law thereof. Any disputes under this Agreement shall be resolved by
      binding arbitration under the rules of the American Arbitration
      Association in Los Angeles, California.

7.    CONFIDENTIALITY

      The Parties, their employees, representatives and agents shall keep, and
      the Parties shall cause their respective affiliates and such affiliates'
      employees, representatives and agents

<PAGE>

      to keep, the provisions of this Agreement strictly confidential and,
      except as may be required in connection with the consummation of the
      transactions contemplated hereby or as may be required by applicable law
      (including the securities laws of the United States) or otherwise
      determined by a court of the competent jurisdiction, shall make no
      disclosure thereof to any person, except the Parties' respective legal
      counsels, accounting and other professional advisors, without the prior
      written consent of the other Parties. The Purchaser may issue a press
      release describing the closing of this transaction and shall provide a
      copy of such press release to the Seller prior to the issuance of such
      press release.

8.    MISCELLANEOUS

8.1   This Agreement including the Schedules to this Agreement (together with
      any documents referred to herein) contains the entire agreement and
      understanding of the Parties and supersedes all prior agreements,
      understandings or arrangements (both oral and written) relating to the
      subject matter of this Agreement. This Agreement does not confer upon any
      person other than the Parties hereto any rights or remedies hereunder,
      except that the Seller may confer the right to receive payments pursuant
      to Sections 2.3 and 2.4 to one or more designees who shall have the right
      to enforce such payment provisions. This Agreement may be amended,
      modified, supplemented or replaced only by written agreement of the
      Parties.

8.2   If any provision or provisions of this Agreement (or of any document
      referred to herein) is or at any time becomes illegal, invalid or
      unenforceable in any respect, the legality, validity and enforceability of
      the remaining provisions of this Agreement (or such document) shall not in
      any way be affected or impaired thereby. Any illegal, invalid or
      unenforceable provision shall be replaced by a valid one, most closely
      approximating to the original intentions of the Parties.

8.3   This Agreement may be executed in any number of counterparts and all of
      such counterparts taken together shall be taken to constitute one and the
      same instrument.

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8.4   Each Party shall pay its own costs and expenses in relation to the
      negotiation, preparation, and implementation of this Agreement, including
      the fees and disbursements of their respective legal, accountancy and
      other advisers.

8.5   Any notice or other communication to be given hereunder shall either be
      delivered personally or sent by registered post or facsimile transmission.
      The address for service of each of the Parties shall be the address stated
      at the head of this Agreement or such other address as the Party to be
      served may have previously notified to the others. All notices shall be
      deemed to have been served as follows:

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

      (b)   if posted, at the expiration of 72 hours after the envelope
            containing the same was delivered into the custody of the postal
            authorities; and

      (c)   if communicated by facsimile transmission, at the time of
            transmission,

            provided that where, in the case of delivery by hand or transmission
      by facsimile, such delivery or transmission occurs after 6pm on a Business
      Day or on a day which is not a Business Day, service shall be deemed to
      occur at 9am on the next following Business Day. In proving such service
      it shall be sufficient to prove that personal delivery was made, or that
      the envelope containing such notice was properly addressed and delivered
      into the custody of the postal authorities as a pre-paid registered
      letter, or that the facsimile transmission was made after obtaining in
      person or by telephone appropriate evidence of the capacity of the
      addressee to receive the same, as the case may be.

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Executed by the Parties on the day and year appearing above.

/s/ LASZLO BLAGA

EXECUTED by Mr. Laszlo Blaga
on behalf of BIOREX KUTATO ES FEJLESZTO RT. ("v.a.")

/s/ STEVEN A. KRIEGSMAN

EXECUTED by Mr. Steven A. Kriegsman
on behalf of CYTRX CORPORATION

/s/ MR. PETER RONA

EXECUTED by Mr. Peter Rona
on behalf of BRX RESEARCH AND DEVELOPMENT COMPANY LTD