<PAGE>   1

AMGEN                   EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
--------------------------------------------------------------------------------


[*]   - Indicates material which has been omitted pursuant to a request for
        confidential treatment, and which has been separately filed.


This Agreement ("Agreement"), between Amgen Inc. ("Amgen") and National Medical
Care, Inc. and Everest Healthcare Services Corporation, including all
subsidiaries and affiliates that are at least fifty and one-tenth percent
(50.10%) owned by National Medical Care, Inc. or Everest Healthcare Services
Corporation listed on Appendix B (collectively, "NMC"), sets forth the terms and
conditions for the purchase of EPOGEN(R) (Epoetin alfa) by NMC. Each of the
parties hereto hereby acknowledges and agrees that National Medical Care, Inc.
shall act on behalf of Everest Healthcare Services Corporation such that any
obligations regarding consents, notices or otherwise, due to or from Everest
Healthcare Services Corporation hereunder shall be deemed satisfied when
delivered to or from National Medical Care, Inc. The parties hereto agree and
acknowledge that this Agreement supersedes Everest Healthcare Services
Corporation's own individual agreement with Amgen to purchase EPOGEN(R) (i.e.
Agreement #980460) (the "Everest Agreement") effective as of December 31, 2000
and that the Everest Agreement was terminated effective as of December 31, 2000.
The final reconciliation of discounts and incentives under the Everest Agreement
through December 31, 2000 will be made as provided in that agreement.

1.   TERM OF AGREEMENT. The "Term" of this Agreement shall be defined as January
     1, 2001 ("Commencement Date") through December 31, 2001 ("Termination
     Date").

2.   QUALIFIED PURCHASES. All terms contained herein apply only to purchases
     made hereunder, as confirmed by Amgen ("Qualified Purchases"), by NMC and,
     subject to the terms of Section 13, all affiliates opened, acquired, or
     managed by NMC during the Term, for so long as such affiliates remain at
     least fifty and one-tenth percent (50.10%) owned or managed by National
     Medical Care, Inc. or Everest Healthcare Services Corporation
     ("Affiliates"), through wholesalers chosen by NMC and authorized by Amgen
     to participate in the program ("Authorized Wholesalers") or directly from
     Amgen. In addition, and also subject to the terms of Section 13, Affiliates
     of Renaissance Health Care, Clinic, Inc., Optimal Renal Care, L.L.C.,
     Integrated Renal Care of the Pacific, and/or any joint venture of NMC in
     which NMC holds at least a fifty and one-tenth percent (50.10%) ownership
     interest, will also be eligible to participate, although not required to
     purchase. Amgen agrees to reasonably approve Authorized Wholesalers
     requested by NMC. The option to purchase on a direct basis from Amgen is
     subject to receipt and approval, not to be unreasonably withheld, of an
     "Application for Direct Ship Account".

3.   PRICING. See Appendix A.

4.   PAYMENT TERMS. The terms and conditions of this Agreement shall apply
     whether NMC and/or Affiliates purchase EPOGEN(R)through an Authorized
     Wholesaler or from Amgen directly.

5.   PRODUCT ACQUISITION COSTS. As long as NMC and Affiliates are the [*]
     non-governmental, freestanding dialysis center (including home dialysis
     affiliates) purchaser of EPOGEN(R) in the United States, Puerto Rico and
     Guam during the Term, on an annual, calendar year basis, Amgen commits that
     this Agreement provides NMC and Affiliates with [*] for EPOGEN(R) available
     to any freestanding dialysis center purchaser in the United States and
     Puerto Rico with comparable growth and percentage of patients with [*] [*].
     If NMC and Affiliates are not the [*] non-governmental, freestanding
     dialysis center purchaser of EPOGEN(R) in the United States, Puerto Rico
     and Guam during the Term, on a calendar year basis, Amgen may provide [*]
     for EPOGEN(R) to [*] non-governmental, freestanding dialysis center
     purchaser(s). Qualification as a freestanding dialysis center shall be
     determined by Amgen in its reasonable discretion, in accordance with
     Amgen's customer classification policies, which generally classify
     freestanding dialysis centers as independent, exclusive providers of
     dialysis services, which (a) may not obtain EPOGEN(R) from or through a
     hospital, or (b) are not otherwise affiliated with a hospital, nursing
     home, or integrated health care system. This commitment excludes [*]
     available to any governmental entities, or [*] mandated by Title 38
     (Veterans' Benefits) or Title 42 (The Public Health and Welfare) of the
     United States Code, or any other federal or state health care program.
     Amgen's agreement to make this commitment is contingent upon its ability to
     comply with all federal, state, local and military laws, statutes and
     regulations.

6.   MINIMUM PRODUCT PURCHASE AGREEMENT. NMC and Affiliates as listed on
     Appendix B on the Commencement Date of this Agreement agree that the
     aggregate EPOGEN(R)purchases during [*] the Term will equal or exceed [*]
     for the same time period during the previous year.

AGREEMENT NO. 20010007               - 1 -                          Ver. 1/12/01

<PAGE>   2

                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
--------------------------------------------------------------------------------


7.   DISCOUNT. Amgen will pay discounts and incentives in accordance with the
     schedule and terms set forth in Appendix A attached hereto.

8.   PAYMENT OF DISCOUNTS. Any discount (hereinafter defined as including a
     discount at time of purchase, rebate, incentive or other concession
     impacting the pricing of a product) earned hereunder shall be calculated in
     accordance with this Agreement, based on Qualified Purchases, using [*] as
     the calculation price, and shall be paid in the form of a [*] to National
     Medical Care's corporate headquarters, except as otherwise provided
     hereunder. NMC and Affiliates shall make available to Amgen any records
     concerning NMC's and Affiliates' purchase amounts that Amgen or its
     auditors may reasonably request. [*]. Amgen will use its best efforts to
     make any discount (excluding discounts at time of purchase) pursuant to
     this Agreement available in accordance with the terms referenced in
     Appendix A. Availability of discounts is contingent upon Amgen receiving
     all relevant purchase data from all Authorized Wholesalers designated by
     NMC, in a form reasonably acceptable to Amgen, detailing NMC's and
     Affiliates' Qualified Purchases of EPOGEN(R) for the relevant period, along
     with any other data required by the terms of Appendix A. In the event of
     any purchases directly from Amgen, all such purchase data shall be included
     in the calculation of all discounts. In no event shall Amgen pay any
     discount on EPOGEN(R) distributed by NMC or Affiliates to non-Affiliates of
     NMC (see Section 2 for definition of Affiliates). Subject to the section
     entitled "Breach of Agreement", in the event that Amgen is notified in
     writing that National Medical Care, Inc. and/or any of its subsidiaries or
     Affiliates (the "Acquiree") is acquired by another entity or a change of
     control otherwise occurs with respect to the Acquiree, any discount which
     may have been earned hereunder prior to the effective date of the
     acquisition shall vest, and shall be paid in the form of a [*] to National
     Medical Care's corporate headquarters subject to the conditions described
     herein.

9.   TREATMENT OF DISCOUNTS. The parties agree that they will account for any
     discount earned hereunder in a way that complies with all applicable
     federal, state, and local laws and regulations, including without
     limitation, Section 1128B(b) of the Social Security Act and its
     implementing regulations, and if required by such statutes or regulations
     (a) claim the benefit of such discount received, in whatever form, in the
     fiscal year in which such discount was earned or the year after, (b) fully
     and accurately report the value of such discount in any cost reports filed
     under Title XVIII or Title XIX of the Social Security Act, or a state
     health care program, and (c) provide, upon request by the U.S. Department
     of Health and Human Services or a state agency or any other federally
     funded state health care program, the information furnished by Amgen
     concerning the amount or value of such discount. NMC agrees that it will
     advise all Affiliates, in writing, of any discount received by National
     Medical Care's corporate headquarters hereunder with respect to purchases
     made by such Affiliates and that NMC will advise said Affiliates as to
     their requirement to account for any such discount in accordance with the
     above stated requirements.

10.  COMMITMENT TO PURCHASE. NMC and Affiliates agrees to purchase EPOGEN(R) for
     all of its dialysis use requirements in the United States, Puerto Rico and
     Guam for recombinant human erythropoietin. Amgen agrees to make such
     EPOGEN(R) available to NMC and Affiliates through its Authorized
     Wholesalers or directly from Amgen. In addition to other remedies available
     to NMC and Affiliates, NMC and Affiliates may purchase another brand of
     recombinant human erythropoietin for its dialysis use requirements in the
     United States, Puerto Rico and Guam if, and only if, NMC and Affiliates
     have informed Amgen, in writing, that NMC and Affiliates are unable to
     acquire sufficient amounts of EPOGEN(R) to meet NMC's and Affiliates'
     reasonable dialysis use requirements, and Amgen by itself, or through its
     Authorized Wholesalers, is actually unable to supply NMC and Affiliates
     with their reasonable dialysis use requirements of EPOGEN(R) within the
     time period reasonably required by NMC and Affiliates, which, in no event
     will be less than five (5) business days after Amgen's receipt of NMC's and
     Affiliates' written notice. If the preceding requirements are met, NMC and
     Affiliates will only be allowed to purchase another brand of recombinant
     human erythropoietin for the time period, and to the extent, that Amgen is
     unable to provide NMC and Affiliates with EPOGEN(R) to meet NMC's and
     Affiliates' reasonable dialysis use requirements.

11.  OWN USE. NMC hereby certifies that EPOGEN(R)purchased hereunder will be for
     the "own use" by NMC and the Affiliates of NMC.

12.  AUTHORIZED WHOLESALERS. A complete list of NMC's and Affiliates' current
     Authorized Wholesalers, through whom NMC and Affiliates may purchase
     EPOGEN(R) hereunder is attached as Appendix C. NMC and Affiliates agrees to
     promptly provide Amgen with any additions, deletions, or changes to the
     initial list of Authorized Wholesalers. Amgen requires no less than 30 days
     notice before the effective date of change for any addition or deletion of
     Authorized Wholesalers hereunder. Any proposed changes to the initial list
     of Authorized Wholesalers must be in writing and are subject to reasonable
     approval by Amgen.

AGREEMENT NO. 20010007               - 2 -                          Ver. 1/12/01

<PAGE>   3

                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
--------------------------------------------------------------------------------


13.  SUBSIDIARIES AND AFFILIATES. Within 30 days of execution of this Agreement,
     NMC shall provide a current listing of all Affiliates, and other entities,
     that will be participating in this Agreement, designating which Affiliates
     are owned and/or managed by NMC. Such listing will be incorporated into
     this Agreement as Appendix B. Only those entities listed on Appendix B will
     be eligible to participate in this Agreement. Any NMC managed Affiliate, or
     other entity with an existing contract, may participate in either their
     existing agreement with Amgen, or this Agreement, but not both. Each
     managed Affiliate or entity must declare under which single Amgen contract
     it will participate. Only Qualified Purchases under this Agreement will be
     used in the calculation of pricing, discounts or other incentives under
     this Agreement. NMC will notify Amgen of changes to Appendix B, and the
     effective date of change. Such effective date of change may not be earlier
     than the date the notice is received by Amgen. Any proposed change to
     Appendix B will be subject to the reasonable approval of Amgen based upon
     Amgen's then current legal and contractual requirements, and such proposed
     affiliate's classification as a freestanding dialysis center or a home
     dialysis support facility.

14.  BREACH OF AGREEMENT. Either party may terminate this Agreement for a
     material breach upon thirty (30) days advance written notice provided such
     breach remains uncured at the end of the thirty (30) day period.

15.  CONFIDENTIALITY. Both Amgen and NMC agree that this Agreement represents
     and contains confidential information which will not be disclosed to any
     third party, or otherwise made public, without prior written authorization
     of the other party, except where such disclosure is contemplated hereunder
     or required by law or court order. In the event NMC believes it is
     obligated to disclose any such information as required by law or court
     order, NMC will provide Amgen with prior written notice and an opportunity
     to seek a protective order and NMC shall furnish only that portion of the
     information that its counsel advises is required to be disclosed by law.

16.  WARRANTIES. Each party represents and warrants to the other that this
     Agreement (a) has been duly authorized, executed, and delivered by it, (b)
     constitutes a valid, legal, and binding agreement enforceable against it in
     accordance with the terms contained herein, and (c) does not conflict with
     or violate any of its other contractual obligations, expressed or implied,
     to which it is a party or by which it may be bound. NMC represents and
     warrants that it has the power to bind National Medical Care, Inc. and the
     subsidiaries and owned Affiliates listed on Appendix B to the terms
     contained herein. NMC shall cause each managed Affiliate to be bound by the
     terms and conditions of this Agreement through the execution of a joinder
     agreement executed between NMC and each such managed Affiliate.

17.  GOVERNING LAW. This Agreement will be governed by the laws of the State of
     Delaware and the parties submit to the jurisdiction of Delaware courts,
     both state and federal.

18.  NOTICES. Any notice or other communication required or permitted hereunder
     will be in writing and shall be deemed given or made when delivered in
     person or when received by the other party sent by U.S. Mail, return
     receipt requested, at the respective party's address set forth below or at
     such other address as the party shall have furnished to the other in
     accordance with this provision.

19.  COMPLIANCE WITH HEALTH CARE PRICING AND PATIENT PRIVACY LEGISLATION AND
     STATUTES. a) Notwithstanding anything contained herein to the contrary, at
     any time following the enactment of any federal, state, or local law or
     regulation that materially reforms, modifies, alters, restricts, or
     otherwise affects the pricing of or reimbursement available for EPOGEN(R),
     either party may initiate good faith negotiations to modify this Agreement.
     If after forty-five (45) days the parties are unable to in good faith
     mutually agree to modifications to this Agreement, (i) either party may
     terminate this Agreement immediately, or (ii) Amgen may exclude any owned
     or managed Affiliates from participating in this Agreement unless such
     owned or managed Affiliate(s) certifies in writing that they are, or will
     be, exempt from the provisions of such enacted law or regulation.
     Additionally, in order to assure compliance with any existing federal,
     state or local statute, regulation or ordinance, Amgen reserves the right,
     in its reasonable discretion, to exclude any owned or managed Affiliates
     from the pricing, discount, and incentive provisions of this Agreement. In
     the event there is a future change in Medicare, Medicaid, or other federal
     or state statutes or regulations or in the interpretation thereof, which
     renders any of the material terms of this Agreement unlawful or
     unenforceable, this Agreement shall continue and shall be amended by the
     parties as a result of good faith negotiations as necessary to bring the
     Agreement into compliance with such statute and regulation.

AGREEMENT NO. 20010007               - 3 -                          Ver. 1/12/01

<PAGE>   4

                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
--------------------------------------------------------------------------------


     b) Notwithstanding anything contained herein to the contrary, in order to
     assure compliance, as determined by either party in its reasonable
     discretion, with any existing federal, state or local statute, regulation
     or ordinance relating to patient privacy of medical records, or at any time
     following the enactment of any federal, state, or local law or regulation
     relating to patient privacy of medical records that in any manner reforms,
     modifies, alters, restricts, or otherwise affects any of the data received
     or to be received in connection with any of the incentives contemplated
     under this Agreement, either party may upon 30 days' notice, seek to modify
     this Agreement. NMC and Amgen shall meet and in good faith seek to mutually
     agree to modify this Agreement to accommodate any such change in law or
     regulation, [*]. If the parties in good faith determine that such
     modification is not possible, the parties shall seek to modify the
     Agreement in another manner acceptable to both parties. If the parties,
     after a reasonable time, are unable to agree upon such a modification,
     either party shall be entitled to terminate the affected incentive upon 30
     days' notice or upon the date such change in law or regulation goes into
     effect, whichever is earlier. [*].

20.  MISCELLANEOUS. No modification of this Agreement shall be effective unless
     made in writing and signed by a duly authorized representative of each
     party. This Agreement constitutes the entire agreement of the parties
     pertaining to the subject matter hereof and supersedes all prior written
     and oral agreements and understandings pertaining hereto including without
     limitation, any previous or existing contract or amendment for the purchase
     of EPOGEN(R). Neither party shall have the right to assign this Agreement
     to a third party without the prior written consent of the other party.
     Neither party shall be liable for delays in performance and nonperformance
     of this Agreement or any covenant contained herein caused by fire, flood,
     storm, earthquake or other act of God, war, rebellion, riot, failure of
     carriers to furnish transportation, strike, lockout or other labor
     disturbances, act of government authority, inability to obtain material or
     equipment, or any other cause of like or different nature beyond the
     control of such party. However, during any time of nonperformance by Amgen
     which involves NMC's and Affiliates' inability to obtain sufficient
     EPOGEN(R) to meet NMC's and Affiliates' reasonable dialysis use
     requirements, the [*] for such nonperformance, the [*] and NMC and
     Affiliates may purchase EPOGEN(R) from another supplier. The parties shall
     execute and deliver all documents, provide all information, and take or
     refrain from taking action as may be necessary or appropriate to achieve
     the purposes of this Agreement. This Agreement may be executed in one or
     more counterparts, each of which is deemed to be an original but all of
     which taken together constitutes one and the same agreement. Amgen reserves
     the right to rescind this offer if the parties fail to execute this
     Agreement within thirty (30) days from the date of its offering.

     Please retain one fully executed original for your records and return the
     other fully executed original to Amgen.


     THE PARTIES EXECUTED THIS AMENDMENT AS OF THE DATES SET FORTH BELOW.

<TABLE>

<S>                                                          <C>
AMGEN INC.                                                   NATIONAL MEDICAL CARE, INC.

Signature:    /s/Richard W. Reese                            Signature:    /s/Ben Lipps
              ----------------------------------------                     ----------------------------------------
Print Name:   RICHARD W. REESE                               Print Name:   BEN LIPPS
              ----------------------------------------                     ----------------------------------------
Print Title:  NATIONAL ACCOUNT, ASSOCIATE DIRECTOR           Print Title:
              ----------------------------------------                     ----------------------------------------
Date:         2-13-01                                        Date:
              ----------------------------------------                     ----------------------------------------

                                                              EVEREST HEALTHCARE HOLDINGS, INC., SUCCESSOR BY
                                                              STATUTORY MERGER TO EVEREST HEALTHCARE SERVICES
                                                              CORPORATION

Signature   /s/Michael Narachi                                Signature:    /s/Ben Lipps
            -----------------------------------------                       ---------------------------------------
Print Name:   VICE PRESIDENT &  GEN'L. MGR. NBU               Print Title:  BEN LIPPS
            -----------------------------------------                       ---------------------------------------
Date:         2-14-01                                         Date:
              ---------------------------------------                       ---------------------------------------

</TABLE>
AGREEMENT NO. 20010007               - 4 -                          Ver. 1/12/01

<PAGE>   5

                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
--------------------------------------------------------------------------------



                APPENDIX A: DISCOUNT PRICING, SCHEDULE, AND TERMS

1.   PRICING. NMC and Affiliates may purchase EPOGEN(R) directly from Amgen or
     through Authorized Wholesalers [*]. Notwithstanding any of the foregoing,
     each of the parties hereto hereby acknowledges and agrees that this
     Agreement is being executed after the Commencement Date and that any
     purchases of EPOGEN(R) made by NMC and Affiliates were and will continue to
     be made [*] from the Commencement Date (January 1, 2001) until such date
     that is 15 days after the date of execution of this Agreement or March 1,
     2001, if mutually agreed upon by the parties (the "Negotiation Period").
     [*] [*]. Resulting prices do not include any wholesaler markup, service
     fees, or other charges. [*]

2.   [*].  NMC may qualify [*] the following requirements must be met:

     A. REQUIREMENTS: In order to qualify [*]. In order to participate [*], NMC
        and Affiliates must provide the following information for each
        dialysis patient to Amgen or to a data collection vendor specified by
        Amgen, on a [*] basis, and no later than [*] after the end of [*]:

     i) facility ID, [*], [*]. Amgen may utilize the Data for any purpose, and
        reserves the right to audit all Data. Notwithstanding the foregoing,
        Amgen shall not sell or re-sell any Data obtained pursuant to this
        Agreement. Additionally, any use by Amgen of such Data shall be in a
        format that does not identify NMC as the source of such Data, unless
        NMC has consented to such use. Under no circumstances should the Data
        include any patient identifiable information including, without
        limitation, name, complete social security number, address or birth
        date. The identity of the account submitting the Data and any
        association with the Data will remain confidential and will not be
        used in a manner that is patient identifiable. The [*] must be derived
        from [*] taken immediately before dialysis treatment using any
        automated [*] must be reported to [*] and must be submitted in a
        format reasonably acceptable to Amgen. Hand written reports are not
        acceptable; electronic submission of the Data is preferred; and


AGREEMENT NO. 20010007               - 5 -                          Ver. 1/12/01

<PAGE>   6

                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
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          APPENDIX A: DISCOUNT PRICING, SCHEDULE, AND TERMS (CONTINUED)

     ii) a properly executed "Annual Certification Letter", a sample of which is
         attached hereto as Exhibit #1, that will be provided to National
         Medical Care's corporate headquarters, unless otherwise requested,
         after this Agreement is executed by both parties.

     B. CALCULATION: Assuming NMC and Affiliates have fulfilled all requirements
        as described in Section 2(a) above, NMC's [*] will be calculated as
        follows: The "Average Patient [*]" for each dialysis patient will be
        based upon the average of all [*] gathered for each patient during
        each [*] of the Term. The [*] of all dialysis patients with Average
        Patient [*] less than [*], will be determined by dividing the total
        number of dialysis patients with Average Patient [*] less than [*], by
        the total number of dialysis patients treated by NMC and Affiliates.
        [*] will be calculated based on NMC's and Affiliates' overall
        performance in accordance with Amgen's discount calculation policies.

     C. PAYMENT: [*] will be calculated on a [*] and paid to National Medical
        Care's corporate headquarters, except as otherwise provided hereunder.
        Payment is contingent upon receipt by Amgen of the Annual
        Certification Letter (attached hereto as Exhibit 1) and all required
        Data for the corresponding quarter. Data shall be submitted to Amgen
        [*], and no later than [*]. If Data is [*], NMC will not qualify for
        the [*] for that [*]. However, if Amgen determines that any
        Affiliate(s) is consistently not submitting the required Data, Amgen
        reserves the right in its reasonable discretion to exclude such
        Affiliate's Qualified Purchases of EPOGEN(R)from the calculation of
        the [*] for any relevant [*]. [*] will be based on the Data received
        from the [*], and will equal a percentage of NMC's and Affiliates'
        total Qualified Purchases of EPOGEN(R)during each relevant [*]
        (exclusive of any Qualified Purchases of EPOGEN(R)made by NMC or any
        Affiliate not meeting the Data submission requirements described
        above) as governed by the [*] schedules listed below. In the event the
        EPOGEN(R)package insert language or the [*] guidelines change, [*]


AGREEMENT NO. 20010007               - 6 -                          Ver. 1/12/01

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                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
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          APPENDIX A: DISCOUNT PRICING, SCHEDULE, AND TERMS (CONTINUED)

                          [*] INCENTIVE [*] SCHEDULES:

                                       [*]











[*]

D. VESTING: [*] will vest on [*] and be paid in accordance with the terms and
   conditions of Section 2 c) Payment above.

AGREEMENT NO. 20010007               - 7 -                          Ver. 1/12/01

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                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
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          APPENDIX A: DISCOUNT PRICING, SCHEDULE, AND TERMS (CONTINUED)

3.   [*] NMC shall be eligible to receive a [*] if certain data elements are
     transmitted to Amgen [*]. The [*] will be calculated as a percentage of
     Qualified Purchases of EPOGEN(R) attributable to NMC and all Affiliates
     during each [*]. In order to qualify for the [*], the following [*] must be
     submitted by NMC and all Affiliates in [*] format reasonably acceptable to
     Amgen [*]: Facility ID, [*], [*]. [*] must be submitted on a [*] basis, and
     no later than [*]. If such [*] is received more than [*], NMC will not
     qualify for the [*]. [*]. However, if Amgen determines that any
     Affiliate(s) is consistently not submitting the required [*], Amgen
     reserves the right in its sole discretion to exclude such Affiliate's
     Qualified Purchases of EPOGEN(R) from the calculation of the [*]. [*].






4.   [*].  NMC may qualify for the [*] as described below.

     A. CALCULATION: NMC's [*] will be calculated in accordance with the
        following formula and with each relevant [*] schedule listed below:





                                   [*] = A x B
         where
                  A = [*].
                  B =  [*].
                  C = [*].
                  D = [*].


AGREEMENT NO. 20010007               - 8 -                          Ver. 1/12/01

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                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
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          APPENDIX A: DISCOUNT PRICING, SCHEDULE, AND TERMS (CONTINUED)

                          [*] INCENTIVE [*] SCHEDULES:

                     [*]

                     [*]














                        [*]

                          [*]



AGREEMENT NO. 20010007               - 9 -                          Ver. 1/12/01

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                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
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          APPENDIX A: DISCOUNT PRICING, SCHEDULE, AND TERMS (CONTINUED)

                               [*] [*] SCHEDULES:

                      [*]

                  [*]


















                             [*]

                        [*]


AGREEMENT NO. 20010007               - 10 -                         Ver. 1/12/01

<PAGE>   11

                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
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          APPENDIX A: DISCOUNT PRICING, SCHEDULE, AND TERMS (CONTINUED)

For the purposes of calculating [*], Amgen will incorporate purchases of any
newly created facility (but not facilities added through acquisition). [*].

B.  VESTING:  NMC's [*] will vest on the [*], and will be paid in accordance
    with the  terms  and  conditions described above.




AGREEMENT NO. 20010007               - 11 -                         Ver. 1/12/01

<PAGE>   12

                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
--------------------------------------------------------------------------------


               APPENDIX B: LIST OF NMC SUBSIDIARIES AND AFFILIATES


                                  SUBSIDIARIES:

       Bio-Medical Applications Management Co., Inc. and its subsidiaries

                                   Erika, Inc.

                               Infusion Care, Inc.

                                 LifeChem, Inc.

                  National Medical Care HomeCare Division, Inc.

                         Renal Research Institute, Inc.

                            Spectra Renal Management

                                   AFFILIATES:

                           See Contract List Attached







AGREEMENT NO. 20010007               - 12 -                         Ver. 1/12/01

<PAGE>   13

                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
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                 APPENDIX C: LIST OF NMC AUTHORIZED WHOLESALERS

TO ENSURE YOU RECEIVE THE APPROPRIATE DISCOUNT, IT IS IMPORTANT THAT WE HAVE
YOUR CURRENT LIST OF AUTHORIZED WHOLESALERS. THE FOLLOWING LIST REPRESENTS THE
WHOLESALERS AMGEN CURRENTLY HAS ASSOCIATED WITH YOUR CONTRACT. PLEASE UPDATE THE
LIST BY ADDING OR DELETING WHOLESALERS AS NECESSARY.

Bergen Brunswig Corporation
4000 Metropolitan Drive
Orange, CA  92668

J.M. Blanco Inc.
Calle D - Lote No. 21
Guaynabo, PR 00965

Metro Medical Supply, Inc.
3332 Powell Avenue
Nashville, TN 37204

Bellco Drug Corporation
101 East Hoffman Avenue
Lindenhurst, NY 11757




AGREEMENT NO. 20010007               - 13 -                         Ver. 1/12/01

<PAGE>   14

                EPOGEN(R) FREESTANDING DIALYSIS CENTER AGREEMENT
--------------------------------------------------------------------------------


                                                                      EXHIBIT #1

                       SAMPLE ANNUAL CERTIFICATION LETTER



Month X, 2001

FSDC Legal Name
Street Address
City, ST  Zip

RE:  EPOGEN(R)(Epoetin alfa) Agreement No. 20010007

Dear ____________:

Thank you for your participation in the [*] Incentive Program. In order for us
to enroll you, we require that a duly authorized representative of your
organization sign the certification below.

Upon receipt of this executed document, we will calculate the value of your
incentive. If we do not receive the executed certification, we cannot provide
you with this incentive.

If you have any questions regarding this letter please contact me at [*]. Thank
you for your assistance in returning this certification.

Sincerely,



[*]
Outcomes Incentive Analyst


CERTIFICATION:

On behalf of FSDC Legal Name and all eligible Affiliates participating in the
[*] Incentive Program under Agreement No. 20010007, the undersigned hereby
certifies that the [*] data submitted for each eligible Affiliate includes the
required [*] results from all dialysis patients of such Affiliate, and does not
include [*] results from non-patients. The party executing this document also
represents and warrants that it (i) has no reason to believe that the submitted
[*] data is incorrect, and (ii) is authorized to make this certification on
behalf of all eligible Affiliates submitting [*] data.

FSDC LEGAL NAME

Signature:            _____________________________

Print Name:           _____________________________

Print Title:          _____________________________

Date:                 _____________________________




AGREEMENT NO. 20010007               - 14 -                         Ver. 1/12/01