<PAGE>


                       ASSIGNMENT AND ASSUMPTION AGREEMENT

                  This Assignment and Assumption Agreement (the "Assignment and
Assumption Agreement"), made and entered into as of December 26, 2000, is by
and between Curative Health Services, Inc., a Minnesota corporation
("Assignor"), and Cytomedix, Inc., a Delaware corporation ("Assignee").

                                   WITNESSETH:

                  WHEREAS, Assignor and Assignee are parties, along with certain
other parties, to that certain Amended and Restated Asset Purchase Agreement
effective as of October 12, 2000 (the "Asset Purchase Agreement"), pursuant to
which Assignee has agreed to purchase certain of the assets of Assignor as set
forth therein; and

                  WHEREAS, pursuant to the Asset Purchase Agreement, Assignor
has agreed to assign certain rights and agreements to Assignee, and Assignee has
agreed to assume certain liabilities and obligations of Assignor, as set forth
herein, and this Assignment and Assumption Agreement is contemplated by Section
2.7(a)(ii) of the Asset Purchase Agreement;

                  NOW, THEREFORE, for and in consideration of the premises and
the mutual covenants contained herein, and for other good and valuable
consideration, the receipt, adequacy and legal sufficiency of which are hereby
acknowledged, the parties do hereby agree as follows:

                  1. Definitions. All capitalized terms used in this Assignment
and Assumption Agreement without definition have the meanings given to them in
the Asset Purchase Agreement.

                  2. Assignment and Assumption. Effective as of the Closing,
Assignor hereby assigns, sells, transfers and conveys (collectively, the
"Assignment") to Assignee all of Assignor's right, title, benefit, privileges
and interest in and to, and all of Assignor's burdens, obligations and
liabilities in connection with, each of the Assumed Liabilities listed on
Schedule A attached hereto. Assignee hereby accepts the Assignment, and assumes
and agrees to observe and perform all of the duties, obligations, terms,
provisions and covenants, and to pay and discharge all of the liabilities of
Assignor to be observed, performed, paid or discharged from and after the
Closing, in connection with the Assumed Liabilities. Assignee assumes no
Retained Liabilities, and the parties hereto agree that all such Retained
Liabilities shall remain the sole responsibility of Assignor.

                  3. Terms of the Asset Purchase Agreement. Assignor
acknowledges and agrees that the representations, warranties, covenants,
agreements and indemnities contained in the Asset Purchase Agreement shall not
be superseded hereby, but shall remain in full force and effect to the full
extent provided therein. In the event of any conflict or inconsistency between
the terms of the Asset Purchase Agreement and the terms hereof, the terms of the
Asset Purchase Agreement shall govern.

                  4. Further Actions. Each of the parties hereto covenants and
agrees, at its own expense, to execute and deliver, at the reasonable request of
the other party hereto, such further instruments of transfer and assignment and
to take such other action as such other party may reasonably request to more
effectively consummate the assignments and assumptions contemplated by this
Assignment and Assumption Agreement.


<PAGE>

                  5. Counterparts. This Assignment and Assumption Agreement may
be executed in one or more counterparts, with the same effect as if the
signatories executed the several counterparts had executed one counterpart. All
such executed counterparts shall together constitute one and the same
instrument.

                  6. Governing Law. This Assignment and Assumption Agreement
will be governed by and construed under the laws of the State of New York
without regard to conflicts of laws principles that would require the
application of any other law.

                  [remainder of page intentionally left blank]




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<PAGE>

     [Cytomedix, Inc. signature page of Assignment and Assumption Agreement]

                  IN WITNESS WHEREOF, the parties, by themselves or their duly
authorized representatives, have executed this Assignment and Assumption
Agreement as of the date first above written.

                               ASSIGNOR:
                               CURATIVE HEALTH SERVICES, INC.


                               By:   /s/ William C. Tella
                                    --------------------------------------------
                               Name: William C. Tella
                                    --------------------------------------------
                               Its:  Senior Vice President, Business Development
                                    --------------------------------------------

                               ASSIGNEE:
                               CYTOMEDIX, INC.


                               By:   /s/ Robin Lee Geller
                                    --------------------------------------------
                               Name: Robin Lee Geller
                                    --------------------------------------------
                               Its:  Vice President
                                    --------------------------------------------




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<PAGE>




                                   SCHEDULE A

                       CYTOMEDIX, INC. ASSUMED LIABILITIES

                                    [omitted]


This schedule has been omitted from this report in accordance with Item 601 of
Regulation S-K. The Registrant hereby agrees to furnish supplementally to the
Securities and Exchange Commission a copy of this schedule upon request.












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