APPOINTMENT OF NETWORK HEALTHCARE
                           HOLDINGS LIMITED (NETCARE)
                AS THE SOLE DISTRIBUTOR WITH THE EXCLUSIVE RIGHTS
                       OF BIOPURE PRODUCT FOR SOUTH AFRICA
                  (hereinafter referred to as "the TERRITORY")


1         NETWORK HEALTHCARE HOLDINGS LIMITED (hereinafter referred to as
          NETCARE) is hereby appointed as the sole distributor with exclusive
          rights to purchase for re-sale in South Africa (hereinafter referred
          to as "the TERRITORY"), the PRODUCT known as Hemopure (hereinafter
          referred to as the "PRODUCT"). The parties may consider from time to
          time increasing the TERRITORY by adding other countries (by agreement
          in writing from time to time) in Africa and the Middle East to the
          TERRITORY.

2         The parties to the Agreement shall be NETCARE, a public company duly
          listed on the Johannesburg Stock Exchange, full and further details
          whereof as well as details of its associated or subsidiary companies,
          are as contained in the pack of documents which have been furnished by
          NETCARE to BIOPURE.

3         In carrying out its mandate, NETCARE may act itself or through the
          vehicle of a subsidiary trading company acceptable to BIOPURE;
          provided that NETCARE shall cause the subsidiary to comply with the
          Agreement and remain responsible for all of its obligations hereunder.

4         The period during which the exclusive rights granted in clause 1 of
          this Agreement shall remain in force, shall be a minimum period of 5
          (FIVE) years effective from the date that the PRODUCT is approved by
          all necessary governmental action for sale in South Africa, subject to
          early termination by either party during the period as provided for in
          clauses 5 and 16.

          The appointment of NETCARE as distributor in clause 1 shall become
          non-exclusive if product licensure in South Africa for HEMOPURE has
          not been obtained on or prior to March 31, 2001.

          This Agreement shall in any event terminate automatically if product
          licensure in South Africa for HEMOPURE has not been obtained on or
          prior to December 31, 2001.

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5         Based on purchase orders received, PRODUCT shall be sent by BIOPURE to
          NETCARE at addresses to be nominated for sale of the PRODUCT at prices
          to be negotiated and fixed, between the parties from time to time.
          Prices shall be a discount from BIOPURE'S list price as in effect from
          time to time for Hemopure. NETCARE shall be responsible for all
          shipping, handling, insurance, import duties, and clearance costs
          relating to the PRODUCT orders. It is understood that HEMOPURE has not
          been approved for sale in any jurisdiction and that no list price
          exists as at the date of signature hereof. Either party may terminate
          this Agreement in the event that pricing feasible to it cannot be
          agreed upon, and neither party shall have any claim against the other
          arising out of such termination.

6         BIOPURE warrants the availability of not be less than 5 000 (Five
          Thousand) 30gram units per annum. The warranted availability of the
          PRODUCT may increase at such time as BIOPURE'S annual capacity exceeds
          100,000 - 30gram units. The parties will agree on annual marketing
          plans, including minimum sales quantities and marketing activities, by
          quarter on or before 30 days prior to each anniversary of the
          effectiveness of the distributorship grant in clause 1.

7         Ownership in the PRODUCT shall pass when invoiced PRODUCT leaves
          BIOPURE'S facility, with payment becoming due upon receipt of shipping
          documents, unless other terms for payment are agreed between the
          parties from time to time.

8         Payment for PRODUCT shall be made by NETCARE to BIOPURE at BIOPURE'S
          nominated banking institution in the United States of America and in
          the currency of United States Dollars.

9         NETCARE undertakes unto and in favour of BIOPURE that it shall, in
          accordance with and to the extent prescribed in the strategy for
          distribution and education set by BIOPURE:-

          9.1      promote and extend sales of BIOPURE PRODUCT within the
                   TERRITORY to all potential purchasers who have been trained
                   in the use of the PRODUCT, and work diligently in order to
                   obtain orders therefor (but only for such use(s) as are set
                   forth on the PRODUCT label), through personal visits to
                   prospective purchasers as well as by correspondence with such
                   purchasers;

          9.2      advertise and distribute printed matter, subject to the prior
                   approval in writing in all cases of BIOPURE as to form,
                   manner, extent and wording of such advertising material
                   distributed;


<PAGE>   3

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          9.3      not directly or indirectly market or sell or represent
                   competing products within the TERRITORY;

          9.4      not to sell PRODUCT directly or indirectly outside of the
                   TERRITORY, and conversely, except as contemplated by clause
                   14.5. BIOPURE shall be obliged to refer all enquiries
                   relating to the PRODUCT within the TERRITORY to NETCARE, and
                   to effect all sales of the PRODUCT in the TERRITORY through
                   NETCARE.

          9.5      to refer all enquiries relating to the PRODUCT outside the
                   TERRITORY received by NETCARE to BIOPURE.

10        NETCARE shall clearly indicate in all dealings relating to the sale of
          the PRODUCT, that it acts as principal and not as agent for and on
          behalf of BIOPURE. NETCARE shall further not incur liability on behalf
          of BIOPURE or in any way pledge or purport to pledge BIOPURE'S credit
          or enter into any contracts that may be binding upon BIOPURE without
          BIOPURE first approving the terms thereof.

11        BIOPURE will indemnify and hold NETCARE harmless in respect of any
          PRODUCT claims that may be instituted against NETCARE arising out of
          the defective manufacture of the PRODUCT.

12        BIOPURE'S list price for the PRODUCT shall serve as a guide for the
          convenience of NETCARE who may reduce such prices at its discretion.

13        NETCARE undertakes:-

          13.1     to safeguard BIOPURE'S commercial intellectual property
                   rights and to immediately bring to BIOPURE'S attention any
                   wrongful use within the TERRITORY of patent, trade mark,
                   emblems, designs or such similar rights which come to
                   NETCARE'S notice.

          13.2     to pass all useful information received by NETCARE which is
                   likely to be of interest or benefit to BIOPURE, relating to
                   the marketing of the PRODUCT within the TERRITORY, onto
                   BIOPURE, and further undertakes at BIOPURE'S cost, to use its
                   best endeavours in order to obtain the registration and
                   approval of the PRODUCT in South Africa with the Medicines
                   Control Council.

          13.3     At a reasonable cost to be agreed upon with BIOPURE and to
                   the extent outside the scope of customary duties of a
                   distributor of pharmaceutical products:-

<PAGE>   4

                                                                               4

                   13.3.1         to use its best endeavours within the
                                  TERRITORY to assist BIOPURE with trials, and
                                  the collection of data in order to assist
                                  BIOPURE in obtaining US FDA approval and
                                  registration of the PRODUCT;

                   13.3.2         to enter into a detailed programme if
                                  requested by BIOPURE relating to clinical
                                  trials to be carried out in South Africa on
                                  the PRODUCT.

         13.4      to be responsible for post marketing surveillance of PRODUCT
                   sold by it and for all warehouse and lot control and other
                   procedures and documentation required by BIOPURE or South
                   African governmental bodies and for adverse event reporting
                   requirements imposed on BIOPURE in any jurisdiction,
                   including the US FDA;

         13.5      to keep accounts and records of enquiries, transactions and
                   proceedings relating to the distribution of the PRODUCT
                   within the TERRITORY, including lot numbers for all sales,
                   and furnish BIOPURE or its nominee with full access to its
                   books and records. NETCARE shall from time to time, but not
                   less often than quarterly and upon request of BIOPURE, supply
                   BIOPURE with reports and returns relating to the
                   distributorship in respect of such matters as may reasonably
                   be required by BIOPURE;

         13.6      not to cede or assign any of its rights or obligations in
                   terms of the Agreement entered into with BIOPURE to
                   sub-agents that may be appointed within the TERRITORY without
                   the written consent of BIOPURE as to the identity of the
                   assignee and the terms of the assignment;

         13.7      not to tamper with markings, alter, obscure or remove the
                   source of origin of the PRODUCT which may be placed on the
                   PRODUCT by BIOPURE;

         13.8      to maintain adequate stock of PRODUCT for the supply to
                   purchasers of the PRODUCT.

14       In terms of the Agreement, BIOPURE undertakes so long as the
         distributorship granted in clause 1 is in effect:-

         14.1      not to sell the PRODUCT to any other entity within the
                   TERRITORY with a view to re-sale of the PRODUCT within the
                   TERRITORY.

<PAGE>   5

                                                                               5

         14.2      to supply such quantities of technical pamphlets, catalogues,
                   advertising material and any other promotional material
                   within its possession with a view to promoting the sale of
                   the PRODUCT within the TERRITORY, as BIOPURE in its
                   discretion deems necessary;

         14.3      to send representatives of BIOPURE to NETCARE at its own
                   cost, for purposes of promoting the sale of its PRODUCT, at
                   such times and in such numbers as BIOPURE shall deem
                   necessary, acting in its discretion;

         14.4      to provide courses for instruction relating to administration
                   of the PRODUCT and to make itself available to Doctors and
                   Specialists in order to demonstrate the PRODUCT. Such courses
                   shall be provided in the Republic of South Africa at the
                   discretion of and with such frequency as shall be determined
                   by BIOPURE with the expense of such courses being carried by
                   BIOPURE.

         14.5      that in the event of BIOPURE dealing directly with customers
                   for the sale of the PRODUCT for ultimate delivery of the
                   PRODUCT within the TERRITORY, and for use in the TERRITORY,
                   NETCARE shall be entitled to be paid a reasonable commission
                   (not less than the net profit NETCARE would have earned had
                   it sold the PRODUCT); provided that BIOPURE shall not pay
                   commissions for "parallel imports" not under BIOPURE'S
                   direction or control.

         14.6      At or prior to the effectiveness of the exclusive
                   distributorship granted herein, to cancel any Distribution
                   Agreements with any party other than NETCARE in the TERRITORY
                   that may conflict with the terms of this Agreement.

15       Upon termination of the Agreement from any cause-

         15.1      NETCARE shall undertake to either dispose of or in such other
                   manner as BIOPURE may direct, deal with samples, technical
                   pamphlets, advertising material etc;

         15.2      NETCARE shall be entitled to offer for sale to BIOPURE at a
                   price equal to that paid by NETCARE together with cost of
                   carriage, insurance duties etc., all PRODUCT purchased by
                   NETCARE for re-sale, and BIOPURE shall be obliged to
                   re-purchase such PRODUCT;

         15.3      In the event that NETCARE is a registrant for the PRODUCT in
                   South Africa, such registration shall be given up effective
                   on BIOPURE'S designation of

<PAGE>   6

                                                                               6

                  a substitute registrant, and NETCARE will execute and deliver
                  all instruments and documents reasonably requested by BIOPURE
                  or the substitute registrant to effect transfer of the
                  registration and/or applications for registration in existence
                  at the time. Should NETCARE fail to sign any such documents
                  within seven days of request therefore, NETCARE hereby
                  irrevocably nominates, constitute and appoints any officer of
                  BIOPURE, with power of substitution , as its attorney and
                  agent, for purposes of giving effect to the aforegoing.

16       TERMINATION

         16.1     This Agreement may be terminated as follows:-

                  16.1.1   NETCARE may terminate this Agreement upon 90 (Ninety)
                           days notice of cancellation;

                  16.1.2   Either party to this Agreement may, by notice
                           to the other party, terminate this Agreement
                           in the event that the other party :-

                           16.1.2.1        shall have committed any
                                           material breach of any
                                           provision of this Agreement
                                           and shall not have remedied
                                           the same within 30 (Thirty)
                                           days after its receipt of
                                           notice of such breach, or

                           16.1.2.2        shall have commenced voluntary
                                           insolvency, bankruptcy,
                                           reorganization, liquidation,
                                           or receivership proceedings or
                                           shall not have obtained a
                                           dismissal of any involuntary
                                           insolvency, bankruptcy,
                                           reorganization, liquidation or
                                           receivership proceedings
                                           commenced against it within 60
                                           (Sixty) days after the
                                           commencement of any such
                                           proceedings.

                  16.1.3   BIOPURE may terminate this Agreement if-

                           16.1.3.1        in BIOPURE'S judgement the
                                           PRODUCT should not be offered
                                           in the TERRITORY or any
                                           portion thereof for any
                                           reason, including but not
                                           limited to safety or usage
                                           experience in the TERRITORY or
                                           any portion thereof;

<PAGE>   7

                                                                               7

                                  16.1.3.2        there is a failure to meet the
                                                  marketing plan for three
                                                  consecutive quarters.

         16.2     Upon termination of this Agreement (unless such termination
                  does not apply to all countries within the TERRITORY at the
                  time) NETCARE shall immediately destroy or return to BIOPURE
                  all such materials in its possession or control containing
                  confidential information, except that NETCARE shall retain and
                  from time to time furnish to BIOPURE any data requested by
                  BIOPURE for regulatory or reporting purposs. BIOPURE shall
                  have exclusive ownership rights, including without limitation
                  the right to review, access and use, either directly or
                  indirectly or by cross-reference or incorporation or
                  otherwise, all information, data, investigations, preclinical
                  and clinical protocols (including without limitation,
                  information relating to laboratory, animal and human studies),
                  and related regulatory approvals pertaining to the PRODUCT
                  possessed or controlled by NETCARE or any of its affiliates,
                  or which NETCARE or any of its affiliates has a right to
                  review, access or use, and NETCARE agrees to execute and
                  deliver to BIOPURE any documents or instruments reasonably
                  requested by BIOPURE in this regard. Further, upon
                  termination, BIOPURE shall have exclusive ownership rights to
                  all trademarks, trade names and other marketing intangibles
                  relating to the PRODUCT, including registrations relating
                  thereto, owned, possessed or controlled by NETCARE or any
                  affiliate of NETCARE and NETCARE agrees to execute and deliver
                  to BIOPURE any documents or instruments requested by BIOPURE
                  in this regard.

                  16.2.1          Should NETCARE fail to perform its obligations
                                  in terms of this clause, within a reasonable
                                  period of time having been called upon so to
                                  act, NETCARE hereby irrevocably nominates,
                                  constitutes and appoints any officer of
                                  BIOPURE with power of substitution, as its
                                  attorney and agent for purposes of giving
                                  effect to aforegoing.

         16.3      The termination of the Agreement shall be without prejudice
                   to any obligation of either party accrued prior thereto or to
                   other available remedies, and any amounts due from NETCARE to
                   BIOPURE shall be paid within 30 (thirty) days thereafter.

         16.4      Failure on the part of either party to notify the other of a
                   breach of this Agreement or either party to terminate the
                   rights granted hereunder because of such breach, shall not
                   constitute a condonation of the breach or a waiver of the



<PAGE>   8

                                                                               8

                   right of either party to terminate the Agreement in
                   accordance with provisions herein contained.

17        In order to distribute the PRODUCT, NETCARE shall be entitled to
          appoint and employ agents within the TERRITORY only with the prior
          written approval of BIOPURE of the terms of any distribution
          agreement, (which shall contain customary representations and
          covenants of the agent or distributor) and the identity of the agent
          or distributor and provided that no such appointment shall relieve
          NETCARE of any of its obligations hereunder.

18       SETTLEMENT OF DISPUTES

         18.1      Should any dispute/s or difference/s whatsoever arise at any
                   time between the parties concerning this Agreement, or its
                   construction or effect or as to the rights, duties and/or
                   liabilities of them or any of them under or by virtue of this
                   Agreement, the parties concerned will meet with each other as
                   soon as is reasonably possible in a bona fide effort to
                   resolve their dispute/s or difference/s without the necessity
                   of declaring a dispute to exist between them;

         18.2      Should the meeting referred to in clause 19.1 above either
                   not take place within a reasonable time, or, having taken
                   place should the dispute/s or difference/s between the
                   parties not be resolved and still exist, then and in either
                   of those events, either of the parties concerned may :-

                   18.2.1       declare a dispute by delivery of the details of
                                the dispute to the other party, and

                   18.2.2       request that the dispute be referred by the
                                parties to arbitration in accordance with the
                                1996 Arbitration Act and resolved further and in
                                accordance with the rules of the London Court of
                                International Arbitration, it being understood
                                that the arbitration shall be held in London
                                unless otherwise agreed to and be completed as
                                soon as possible.

         18.3      There shall be one arbitrator who shall be, if the question
                   in issue is:-

                   18.3.1       primarily an accounting matter, an independent
                                chartered accountant; or

                   18.3.2       primarily a legal matter, a practising senior
                                counsel; or

<PAGE>   9

                                                                               9

                   18.3.3       primarily a medical matter, a suitably qualified
                                person; and

                   18.3.4       any other matter, a suitably qualified person

         18.4      The appointment of the arbitrator shall be agreed mutually
                   between the parties, but failing agreement between them
                   within a period of 14 days after the arbitration has been
                   demanded, either of the parties shall be entitled to request
                   the Commissioner for the time being of the London Court of
                   International Arbitration to make the appointment who, in
                   making his/her appointment, shall have regard to the nature
                   of the dispute.

         18.5      The arbitrator shall have the powers conferred upon an
                   arbitrator under the 1996 Arbitration Act as amended or
                   re-enacted in some other form from time to time, but shall be
                   entitled to decide on such procedures as he/she may consider
                   desirable for the expedient determination of the dispute, and
                   in particular he/she shall have the sole and absolute
                   discretion to determine whether and to what extent it shall
                   be necessary to file pleadings, make discovery of documents
                   or hear oral evidence.

19       DOMICILIA

         19.1      The parties choose as their domicilium citandi et executandi
                   their respective addresses as set out in this clause for all
                   purposes arising out of or in connection with this Agreement
                   at which addresses all processes and notices arising out of
                   or in connection with this Agreement, its breach or
                   termination may validly be served upon or delivered to the
                   parties.

         19.2      For the purposes of this Agreement, the parties' respective
                   addresses shall be:

                   19.2.1       NETCARE:
                                Sanlam Park South
                                9 Fredman Drive
                                Sandton

                   19.2.2       BIOPURE:
                                11 Hurley Street
                                Cambridge, MA 02141


<PAGE>   10
                                                                              10


                   or such other address, not being a post office box or poste
                   restante, of which the party concerned may notify the others
                   in writing.


         19.3      Any notice given in terms of this Agreement shall be in
                   writing and shall -

                   19.3.1       if delivered by hand be deemed to have been duly
                                received by the addressee on the date of
                                delivery;

                   19.3.2       if transmitted by telex or facsimile be deemed
                                to have been received by the addressee 1 (One)
                                day after dispatch;

                  unless the contrary is proved.

         19.4     Notwithstanding anything to the contrary contained in this
                  Agreement, a written notice or communication actually received
                  by one of the parties from another including by way of telex
                  or facsimile transmission shall be adequate written notice or
                  communication to such party

20       NON-WAIVER

         No waiver by any/either of the parties of any of their rights arising
         out of or under this Agreement shall prevent that party from relying
         upon strict compliance by the other party hereto with all of its
         obligations arising out of or under this Agreement upon that/or any
         subsequent or future occasion.

21       WHOLE AGREEMENT

         This is the whole agreement between the parties who/which acknowledge
         that they have not been induced to enter into this Agreement by any
         representations or warranties other than those set out or contained
         herein. No alteration, amendment, variation or consensual termination
         of this Agreement shall be of any force or effect unless reduced to
         writing and signed by the parties hereto.

22       FORCE MAJEURE

<PAGE>   11

                                                                              11

         A party is not liable for a failure to perform any of its obligations
in so far as it proves:

         22.1     that the failure was due to an impediment beyond its control,
                  Acts of God, or refusal by any government authority to permit
                  either party to provide its services or limit either party
                  from carrying out its obligations;

         22.2     that it could not reasonably be expected to have taken the
                  impediment and its effects upon the party's ability to perform
                  into account at the time of the contract;

         22.3     that it could not reasonably have avoided or overcome their
                  impediment or at least its effects;

         22.4     an impediment in subclause 22.3 may result from events such
                  as the following, this enumeration not being exhaustive:

                  22.4.1   war, whether declared or not, civil war, civil
                           violence, riots and acts of sabotage;

                  22.4.2   natural disasters;



                  22.4.3   explosions, fires, destruction of machines and of
                           any kind of installations;

                  22.4.4   boycotts, strikes and lock-outs of all kinds,
                           go-slows, occupation of buildings and premises.

23      GOOD FAITH

        The parties shall have a duty of utmost good faith towards one another
        in the performance of their duties in terms of this agreement, and shall
        give one another every co-operation reasonably necessary for purposes of
        promoting the interests of each other.

24      APPLICABLE LAW AND JURISDICTION

<PAGE>   12

                                                                              12

         Save as may otherwise be provided in this Agreement, this Agreement
         shall be governed and interpreted in accordance with the Laws of the
         Republic of South Africa.

25       CONFIDENTIAL INFORMATION

         All information previously acquired or acquired by NETCARE (such term
         for purposes of this clause 29 to include all affiliates of NETCARE) or
         any affiliate thereof, during the term of this Agreement, relating
         directly or indirectly to the present or potential business,
         operations, corporate or financial situation of BIOPURE, or to
         know-how, improvements, patents, data, test results, techniques,
         processes, procedures, raw materials, dealer, supplier and customer
         lists, capitalization and financial information is confidential and
         shall be held in trust by NETCARE for the exclusive benefit of BIOPURE.
         NETCARE and its affiliates shall not use such information except for
         appropriate purposes under this Agreement. Confidential information
         shall be immediately returned to BIOPURE upon its request, along with
         any copies, reproductions, digests, abstracts or the like of all or any
         part thereof in the possession or under the control of NETCARE or any
         of its affiliates and any computer entries or the like relating thereto
         shall be destroyed. The obligation of non-disclosure and non-use herein
         shall survive termination of this Agreement. This clause 29 shall not
         apply with respect to any portion of BIOPURE'S information that :-

         25.1     was already in NETCARE'S possession at the time of receipt by
                  NETCARE, as evidenced by written documents predating the date
                  of this Agreement;

         25.2     is public knowledge at the time of its disclosure to NETCARE
                  by BIOPURE, or becomes public knowledge after its disclosure
                  to NETCARE by BIOPURE, through no act or omission by NETCARE
                  or on NETCARE'S behalf;

         25.3     is lawfully disclosed or made available to NETCARE by a third
                  party having no obligation to BIOPURE to maintain the
                  confidentiality of such information; or

<PAGE>   13

                                                                              13

         25.4     is required by law, regulation, rule, act or order of any
                  governmental authority or agency to be disclosed by NETCARE
                  (but only to the extent so required) and following reasonable
                  written notice by NETCARE to BIOPURE of the requirement prior
                  to disclosure.

26       Each party shall bear its own costs of and incidental to the drafting,
         negotiating and conclusion of this Agreement.


27       REPRESENTATIONS AND WARRANTIES OF NETCARE

         27.1     NETCARE has full right, power and capacity to execute, deliver
                  and perform this Agreement and all corporate action necessary
                  to authorize the execution, delivery and performance by
                  NETCARE of this Agreement has been duly taken. This Agreement
                  constitutes a valid and binding agreement of NETCARE.

         27.2     The execution , delivery and performance by NETCARE of this
                  Agreement will not violate, conflict with, or constitute a
                  default under NETCARE'S charter or other constitutional
                  documents or terms and provisions of any material agreement,
                  license, trust, indenture, mortgage, instrument or restriction
                  to which NETCARE is a party or by judgment, decree, order,
                  writ or injunction applicable to NETCARE or any of its assets
                  or property. No joint venture, partnership or research
                  agreement does or will impair the ability of NETCARE to enter
                  into and be bound by this Agreement or to consummate the
                  transactions contemplated thereby.

         27.3     Interest in Competitors. Neither NETCARE nor any of its
                  subsidiaries nor, to the best of NETCARE'S knowledge after due
                  investigation, any of its executive officers or directors, has
                  any interest, either by way of contract or by way of
                  investment (other than as holder of not more than 5% of the
                  outstanding capital stock of a publicly traded entity) or
                  otherwise, directly or indirectly in any entity that is
                  conducting research or development with respect to any oxygen
                  therapeutic product.

<PAGE>   14

                                                                              14


THUS DONE and SIGNED at _____________________________ on the ____________ day of
2000 in the presence of the undersigned witnesses.


AS WITNESSES:


1.       ___________________________________


2.       ___________________________________

                                                   _____________________________
                                                   FOR:  NETCARE



<PAGE>   15

                                                                              15


THUS DONE and SIGNED at ___________________________ on the _____________ day
of 2000 in the presence of the undersigned witnesses.


AS WITNESSES:

1        __________________________________


2        __________________________________


                                                 _______________________________
                                                 FOR: BIOPURE



<PAGE>   16
                      ADDENDUM TO AGREEMENT ENTERED INTO BY
                                   AND BETWEEN
                     NETWORK HEALTHCARE HOLDINGS LIMITED and
                      BIOPURE LIMITED dated 29th June 2000


WHEREAS: NETCARE and BIOPURE have concluded an Agreement ("the Agreement") with
each other in terms whereof NETCARE have been appointed the sole Distributor
with exclusive rights of BIOPURE PRODUCT for South Africa ("the Territory"); and

WHEREAS: In terms of clauses 13.2 and 13.3 of the AGREEMENT, NETCARE has
undertaken unto and in favour of BIOPURE to use its best endeavours to assist
BIOPURE in obtaining registration of the PRODUCT in South Africa.

In order to facilitate registration of the PRODUCT, NETCARE has entered into a
Joint Venture Agreement with Malesela Holdings Limited (MALESELA), in terms
whereof NETCARE and MALESELA have registered a company Basfour 2170 (Pty)
Limited, Registration Number 2000/012141/07 (BASFOUR) and in which Company both
NETCARE and MALESELA are joint shareholders.

In terms of a written Agreement of Cession annexed hereto, BASFOUR have taken
Cession of NETCARE'S rights and obligations as provided for in the Agreement.

Notwithstanding the Cession afore referred to, NETCARE binds itself as surety
and co-principal debtor unto and in favour of BIOPURE and indemnifies and holds
harmless BIOPURE in respect of any action of any nature whatsoever that may be
instituted by BIOPURE as against BASFOUR, and undertakes to remain liable and
responsible for and to ensure performance by BASFOUR of its obligations as
contained in the Agreement.

BASFOUR Limited has used and shall continue to use its best endeavours to assist
BIOPURE in obtaining registration of the PRODUCT. In so doing, BASFOUR shall

<PAGE>   17


                                                                               2

enter into detailed programmes at substantial cost and effort to BASFOUR
relating to the registration of the PRODUCT being carried out in South Africa.

In addition to BIOPURE making payment to BASFOUR in respect of disbursement and
agreed fees to be charged by BASFOUR to BIOPURE arising out endeavours made to
register the PRODUCT and as more fully referred to in paragraph 13.3 of the
Agreement, BIOPURE further agrees:-

(i)      to extend the definition of "Territory" in the Agreement to include all
         countries on the continent of Africa with the exception of Egypt;

(ii)     that the definition of "Product" in the Agreement shall be extended to
         include Oxyglobin (Hemoglobin Glutamer 200 (Bovine);

(iii)    BIOPURE consents to the Cession entered into by and between Netcare as
         Cedent and BASFOUR as Cessionary.


The remaining terms and conditions of the Agreement shall remain of full force
and effect.


THUS DONE and SIGNED at ___________________________ on the ______________ day
of 2000 in the presence of the undersigned witnesses.


AS WITNESSES:

1.       ___________________________


2.       ___________________________


                                              __________________________________
                                              FOR:  NETCARE


<PAGE>   18

                                                                               3

THUS DONE and SIGNED at ______________________________ on the ___________ day
of 2000 in the presence of the undersigned witnesses.

AS WITNESSES:

1.       ___________________________


2.       ___________________________

                                               _________________________________
                                               FOR:  BIOPURE

Source: OneCLE Business Contracts.