Document:

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                                                                    EXHIBIT 10.8

                   TAX SHARING AND INDEMNIFICATION AGREEMENT

     THIS TAX SHARING AND INDEMNIFICATION AGREEMENT ("Agreement") is made and
entered into as of July 25, 2001, by and between American BioScience, Inc., a
California corporation ("ABI"), and American Pharmaceutical Partners, Inc., a
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California corporation ("APP").

                                    RECITALS

     A.  ABI is the common parent corporation of an affiliated group of
corporations (the "ABI Consolidated Group") within the meaning of Section
1504(a) of the Internal Revenue Code of 1986, as amended (the "Code").  The ABI
Consolidated Group includes APP.  The ABI Consolidated Group have heretofore
joined in the filing of consolidated federal income tax returns.

     B.  ABI expects that as a result of sales of shares of APP, including
through a public offering, APP will cease to be a member of the ABI Consolidated
Group, although APP may continue to be included in Combined Tax returns (as
defined herein).

     C.  ABI and APP desire to provide for the payment of Income Taxes (as
defined herein) and entitlement to refunds thereof, allocate responsibility and
provide for cooperation in connection with the filing of returns in respect of
Income Taxes, and provide for certain other matters relating to Income Taxes.

     NOW, THEREFORE, in consideration of the agreements contained herein and
intending to be legally bound hereby, ABI and APP agree as follows:

                                  ARTICLE 1.
                                 DEFINITIONS

     1.1  Definitions.

     For purposes of this Agreement, the terms set forth below shall have the
following meanings, in addition to the terms defined elsewhere in this
Agreement:

     (a)  "Actually Realized" or "Actually Realizes" shall mean, for purposes of
determining the timing of the occurrence of any Income Tax Benefit, the time at
which the amount of Income Taxes paid by such person is reduced below the amount
of Income Taxes that such person would have been required to pay but for the
occurrence of such Income Tax Benefit. In the case of an Income Tax Benefit in
the form of a Refund, "Actually Realized" or "Actually Realizes" means the date
such Refund is received.

     (b)  "Carryback" shall mean the carryback of a Tax Asset (including,
without limitation, a net operating loss, a net capital loss or a tax credit) by
APP from a Post-Deconsolidation Taxable Period to a Pre-Deconsolidation Taxable
Period.

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     (c)  "Combined Tax" shall mean, with respect to each foreign, state or
local taxing jurisdiction, any Income Tax payable to such foreign, state or
local taxing jurisdiction in which a member of the APP Group files tax returns
with a member of the ABI Sub-Group, on a consolidated, combined, or unitary
basis for purposes of such Income Tax.

     (d)  "Deconsolidation" shall mean any event pursuant to which APP ceases to
be a member of the ABI Consolidated Group.

     (e)  "Deconsolidation Date" means the day on which APP ceases to be a
member of the ABI Consolidated Group, as determined under Treas. Reg. (S)1.1502-
76(b).

     (f)  "Federal Tax" shall mean any tax imposed under Subtitle A of the Code.

     (g)  "Final Determination" shall mean (i) with respect to Federal Taxes, a
"determination" as defined in Section 1313(a) of the Code or execution of an
Internal Revenue Service Form 870AD and, with respect to taxes other than
Federal Taxes, any final determination of liability in respect of a tax that,
under applicable law, is not subject to further appeal, review, or modification
through proceedings or otherwise, (ii) any final disposition of a tax issue by
reason of the expiration of a statute of limitations, or (iii) the payment of
tax by ABI with respect to any item disallowed or adjusted by any taxing
authority where ABI determines in good faith that no action should be taken to
recoup such payment.

     (h)  "ABI Consolidated Group" shall mean, at any time, ABI and each direct
and indirect corporate subsidiary eligible to join with ABI in the filing of a
consolidated Federal Tax return.

     (i)  "ABI Sub-Group" shall mean, at any time, ABI and each of its direct
and indirect corporate subsidiaries other than those subsidiaries that are
members of the APP Group.

     (j)  "ABI Sub-Group Separate Return" shall mean an Income Tax return of ABI
or a member of the ABI Sub-Group for a Post-Deconsolidation Tax Period other
than a Combined Tax return.

     (k)  "Income Tax" (i) shall mean (A) any foreign or any United States
federal, state or local tax, charge, fee, impost, levy or other assessment which
is based upon, measured by, or calculated with respect to (1) net income or
profits (including, but not limited to, any capital gains, gross receipts, or
minimum tax, and any tax on items of tax preference, but not including sales,
use, value added, real property gains, real or personal property, transfer or
similar taxes), or (2) multiple bases (including, but not limited to, corporate
franchise, doing business or occupation taxes), if one or more of the bases upon
which tax may be based, by which it may be measured, or with respect to which it
may be calculated, is described in clause (i)(A)(1) of this definition, together
with (B) any interest, penalties, fines, additions to tax or additional amounts
imposed by any taxing jurisdiction with respect thereto,

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and (ii) shall include any transferee liability in respect of an amount
described in clause (i) of this definition.

     (l)  "Income Tax Benefit" shall mean, in respect of a person or group of
persons for any taxable period, the excess of (A) the hypothetical Income Tax
liability of such person or group of persons for such taxable period, calculated
as if the use of a Tax Asset had not occurred but with all other facts
unchanged, over (B) the actual Income Tax liability of such person or group of
persons for such taxable period, calculated taking into account the use of such
Tax Asset (and treating a Refund as a negative Income Tax liability, and taking
into account credits (if any), for purposes of such calculation).

     (m)  "APP Combined Tax Liability" shall mean, with respect to any
jurisdiction and any taxable year or part thereof for which Combined Tax is due,
an amount of Combined Tax determined in accordance with the principles set forth
in the definition of APP Federal Tax Liability; provided, however, that the
total amount of the APP Combined Tax Liability shall also include, to the extent
not included after application of the principles set forth in the definition of
APP Federal Tax Liability, any actual Income Tax liability owed in a
jurisdiction in which a member of the APP Group files or is included in a
Combined Tax return, to the extent the Income Tax liability shown on such return
exceeds the amount of such liability that would have been owed had no member of
the APP Group been included in such return.

     (n)  "APP Federal Tax Liability" shall mean, with respect to any taxable
year or portion thereof during which APP is a member of the ABI Consolidated
Group, the sum of the APP Group's Federal Income Tax liability, computed as if
the APP Group were not and never were part of the ABI Consolidated Group, but
rather were a separate affiliated group of corporations filing a consolidated
federal income tax return pursuant to Section 1501 of the Code; provided,
however, that transactions with members of the ABI Sub-Group shall be reflected
according to the provisions of the consolidated return regulations promulgated
under the Code governing intercompany transactions, and that Deconsolidation
will trigger any deferred amounts, excess loss accounts, or similar items. Such
computation shall be made (A) without regard to the income, deductions
(including net operating loss and capital loss deductions), and credits in any
year of any member of the ABI Consolidated Group that is not a member of the APP
Group, (B) by taking account of all Tax Assets of the APP Group other than any
Tax Asset which produces an Income Tax Benefit to ABI in accordance with Section
2.1(c)(iii) and (C) reflecting the positions, elections, and accounting methods
used by ABI in preparing the consolidated Federal Tax return for the ABI
Consolidated Group.

     (o)  "APP Group" shall mean, at any time, APP and any direct or indirect
corporate subsidiaries of APP that would be eligible to join with APP, with
respect to Federal Taxes, in the filing of a consolidated federal income tax
return and, with respect to Combined Taxes, in the filing of a consolidated,
combined, or unitary

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Income Tax return if APP were not consolidated, combined, or filing on a unitary
basis with any member of the ABI Sub-Group.

     (p)  "APP Group Separate Return" shall mean an Income Tax return of APP or
a member of the APP Group for a Post-Deconsolidation Tax Period other than a
Combined Tax return.

     (q)  "Post-Deconsolidation Tax Period" means (i) any tax period, or portion
thereof, beginning and ending after the date of Deconsolidation, and (ii) with
respect to a tax period that begins before and ends after the date of
Deconsolidation, such portion of the tax period that commences on the day
immediately after the date of Deconsolidation.

     (r)  "Pre-Deconsolidation Tax Period" means (i) any tax period, or portion
thereof, beginning and ending before or on the date of Deconsolidation, and (ii)
with respect to a period that begins before and ends after the date of
Deconsolidation, such portion of the tax period ending on and including the date
of Deconsolidation.

     (s)  "Refund" shall mean any refund of Income Taxes, including any
reduction in Income Tax liabilities by means of a credit, offset or otherwise.

     (t)  "Tax Asset" means any net operating loss, net capital loss, investment
tax credit, foreign tax credit, charitable deduction, or any other deduction,
credit, or tax attribute which could reduce Income Tax (including, without
limitation, deductions and credits related to alternative minimum taxes).

     1.2  Internal References.

     Unless the context indicates otherwise, references to Articles, Sections,
and paragraphs shall refer to the corresponding articles, sections, and
paragraphs in this Agreement and references to the parties shall mean the
parties to this Agreement.

                                  ARTICLE 2.
                                 TAX SHARING

     2.1  Tax Sharing.

     (a)  General.  For each taxable year of the ABI Consolidated Group during
which income, loss, or credit against tax of the APP Group is includible in the
consolidated Federal Tax return of the ABI Consolidated Group, APP shall pay to
ABI an amount equal to the APP Federal Tax Liability, and for each taxable
period during which income, loss, or credit against tax of any member of the APP
Group is includible in a return relating to a Combined Tax, APP shall pay to ABI
an amount equal to the APP Combined Tax Liability for such taxable period, each
as shown on the Pro Forma Returns (as defined in paragraph (c) below). Subject
to receipt of the payments described in the first two sentences of this Section
2.1(a), and subject to the provisions of Section 2.1(d), ABI shall be liable for
and shall indemnify the APP

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Group against all Income Taxes due with respect of all consolidated Federal Tax
returns of the ABI Consolidated Group, and all returns relating to a Combined
Tax.

     (b)  Estimated Payments.  For each taxable period as to which Section
2.1(a) applies, ABI may determine the amount of the estimated tax installment of
the APP Federal Tax Liability (corresponding to ABI's estimated Federal Tax
installment), as determined under the principles of Section 2.1(a). If ABI makes
such a determination, APP shall pay to ABI, within ten (10) business days (i) of
the statutorily mandated payment date or (ii), if later, of the date of delivery
of a written request for such payment under this Section 2.1(b), the amount so
determined. In addition for each taxable period as to which Section 2.1(a)
applies, ABI may determine under provisions of applicable law the amount of the
estimated tax installment of the APP Combined Tax Liability (corresponding to
the relevant estimated Combined Tax installment), as determined under the
principles of Section 2.1(a). If ABI makes such a determination, APP shall pay
to ABI, within ten (10) business days (i) of the statutorily mandated payment
date or (ii), if later, of the date of delivery of a written request for such
payment under this Section 2.1(b), the amount so determined.

     (c)  Payment of Taxes at Year-End.

     (i)  Within thirty (30) days after the date the ABI Consolidated Group's
     Federal Tax return is filed, ABI shall make available to APP a pro forma
     Federal Tax return (a "Pro Forma Federal Return") of the APP Group
     reflecting the APP Federal Tax Liability. Within thirty (30) days after the
     date the last Combined Tax return is filed for the fiscal year to which
     such returns relate, ABI shall make available to APP the relevant pro forma
     Combined Tax returns (each a "Pro Forma Combined Tax Return" and together
     with the Pro Forma Federal Returns, the "Pro Forma Returns") of the APP
     Group reflecting the relevant APP Combined Tax Liability. The Pro Forma
     Returns shall be prepared in good faith in a manner generally consistent
     with past practice.

     (ii) Within ten (10) days of the receipt by APP of a Pro Forma Federal
     Return, APP shall pay to ABI, or ABI shall pay to APP, as appropriate, an
     amount equal to the difference, if any, between the APP Federal Tax
     Liability reflected on the Pro Forma Federal Return for such year and the
     aggregate amount of the estimated installments of the APP Federal Tax
     Liability for such year made pursuant to Section 2.1(b). Within ten (10)
     days of the receipt of the Pro Form Combined Tax Returns, APP shall pay to
     ABI, or ABI shall pay to APP, as appropriate, an amount equal to the
     difference, if any, between the APP Combined Tax Liability reflected on the
     relevant Pro Forma Combined Tax Returns and the aggregate amount of the
     estimated installments paid with respect to the corresponding APP Combined
     Tax Liability pursuant to Section 2.1(b).

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     (iii)  If, under applicable law and consistent with this Agreement, the ABI
     Sub-Group avails itself of a Tax Asset of the APP Group, ABI shall pay to
     APP an amount equal to the Income Tax Benefit attributable to such Tax
     Asset, if and when Actually Realized by ABI. The parties agree that all net
     operating losses and net capital losses of the ABI Consolidated Group shall
     be taken into account by ABI in the order in which such net operating
     losses and net capital losses have arisen; all other Tax Assets of the APP
     Group shall be taken into account by ABI in the above-described manner,
     subject, however, to the ordering rules then in effect under the Code.

     (iv) In the event that ABI makes a cash deposit with a taxing authority in
     order to stop the running of interest or makes a payment of tax and
     correspondingly takes action to recoup such payment (such as suing for a
     refund), APP shall pay to ABI, within ten (10) days (i) of the date such
     cash deposit is made by ABI or (ii) if later, of the date of delivery of a
     written request for such payment under this Section 2.1(c)(iv), an amount
     equal to APP's share of the amount so deposited or paid (calculated in a
     manner consistent with the determinations provided in this Article 2). Upon
     receipt by ABI of a refund of any amounts paid by it in respect of which
     APP shall have advanced an amount hereunder, ABI shall pay to APP the
     amount of such refund, together with any interest received by it on such
     refund, within ten (10) days of the receipt of such refund. If and to the
     extent that any claim for refund or contest based thereupon shall be
     unsuccessful, the payment by APP under this Section 2.1(c)(iv) may be
     credited by ABI toward any of APP's obligations under this Section 2.1.

     (d)  Treatment of Adjustments.  If any adjustment is made in a Federal Tax
return of the ABI Consolidated Group or in a return relating to a Combined Tax
of the ABI Consolidated Group, after the filing thereof, in which income or loss
of the APP Group (or any member thereof) is included, then at the time of a
Final Determination of the adjustment APP shall pay to ABI, or ABI shall pay to
APP, as the case may be, the difference between all payments actually made under
Section 2.1 with respect to the taxable year or period covered by such tax
return and all payments that would have been made under Section 2.1 taking such
adjustment into account together with any penalties actually paid and interest
for each day until the date of Final Determination calculated at the rate
determined, in the case of a payment by APP, under Section 6621(a)(2) of the
Code and, in the case of a payment by ABI, under Section 6621(a)(1) of the Code.

     (e)  Preparation of Consolidated and Combined Returns.  For all taxable
periods ending on or before the Deconsolidation Date, so long as the ABI
Consolidated Group elects to file (i) consolidated Federal Tax returns as
permitted by Section 1501 of the Code or (ii) any Combined Tax return as
permitted by applicable state law, APP shall consent to the filing of such
returns by ABI. ABI shall prepare and file such returns and any other returns,
documents, or statements required to be filed with the Internal Revenue Service
with respect to the determination of the Federal Tax liability of the ABI
Consolidated Group and with

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the appropriate taxing authorities with respect to the determination of a
Combined Tax liability. With respect to such return preparation, ABI shall act
in good faith with regard to all members included in an applicable return. ABI
shall have the right with respect to any consolidated Federal Tax return or
return relating to a Combined Tax that it has filed or will file to determine in
good faith (i) the manner in which such returns, documents or statements shall
be prepared and filed, including, without limitation, the manner in which any
item of income, gain, loss, deduction or credit shall be reported, (ii) whether
any extensions should be requested, and (iii) the elections that will be made by
any member of the ABI Consolidated Group.

     (f)  Contest of Consolidated and Combined Returns. ABI shall have the
right, in good faith, to (i) contest, compromise, or settle any adjustment or
deficiency proposed, or as a result of any audit of any Federal Tax return or
return relating to a Combined Tax, (ii) file, prosecute, compromise or settle
any claim for refund, and (iii) determine whether any refunds shall be received
by way of refund or credited against tax liabilities. In addition, ABI shall
prepare and file ruling requests, and take all other actions on behalf of any
member of the ABI Consolidated Group that it deems appropriate in providing tax
services to the members of the ABI Consolidated Group. ABI shall, to the extent
such information is available, advise APP of any significant APP tax issue being
audited or contested by the federal, state, local or other relevant taxing
authorities, shall keep APP informed with respect to any audit, contest,
compromise or settlement thereof, and shall provide to APP copies (subject to
deletion of nonrelevant information) of all material correspondence relating to
such contest.

     (g)  APP Consent.  Notwithstanding anything to the contrary in Section
2.1(e) or Section 2.1(f), except as ABI shall determine, in good faith, is
required by law, without the express written consent of APP, which consent shall
not be unreasonably withheld or delayed, ABI shall not file any amended Federal
Tax return or Combined Tax return, settle any tax claim or assessment, file any
ruling request, make any Tax election, or surrender any right to claim a Refund,
if a principal effect of such action is to increase a APP Federal Tax Liability
or a APP Combined Tax Liability.

     (h)  Separate Returns.  APP shall prepare, or cause to be prepared, and
file, or cause to be filed, all APP Group Separate Returns, and shall pay, or
cause to be paid, all Income Tax due with respect to such returns. ABI shall
prepare, or cause to be prepared, and file, or cause to be filed, all ABI Sub-
Group Separate Returns, and shall pay, or cause to be paid, all Income Tax due
with respect to such returns.

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                                  ARTICLE 3.
                             POST-DECONSOLIDATION

     3.1  Additional Rights and Liabilities Post-Deconsolidation.

     (a)  Apportionment of Tax Attributes.  If the ABI Consolidated Group has a
Tax Asset, the portion, if any, of such Tax Asset that shall be apportioned to
the APP Group and treated as a carryover to the first Post-Deconsolidation
taxable period of the APP Group shall be determined in accordance with Treasury
Regulations (S)(S)1.1502-79 and 1.1502-79A; provided, however, that the portion,
if any, of any consolidated unused foreign tax credit which shall be apportioned
to the APP Group shall be determined separately with respect to each of the
items of income listed in Code section 904(d). No Federal Tax Asset of the ABI
Consolidated Group, other than those described in the first sentence hereof, and
no Combined Tax Asset of the ABI Consolidated Group, shall be apportioned to the
APP Group, except as ABI determines is otherwise required under the provisions
of applicable law. ABI shall determine the portion, if any, of any Tax Asset
which must (absent a Final Determination to the contrary) be apportioned to the
APP Group in accordance with this Section 3.1(a) and applicable law, and shall
provide written notice of the calculation thereof to APP as soon as practicable
after the information necessary to make such calculation becomes available to
ABI.

     (b)  Apportionment of Consolidated Section 382 Limitation. In the event
that, after the date of this Agreement and prior to Deconsolidation, the ABI
Consolidated Group suffers an ownership change resulting in a consolidated
Section 382 limitation (within the meaning of Treasury Regulations (S)1.1502-
95T), then, upon Deconsolidation, ABI shall equitably apportion the consolidated
Section 382 limitation between the ABI Sub-Group and the APP Group as permitted
by Treasury Regulations (S)1.1502-95T(c) and shall prepare and file the election
to apportion the consolidated Section 382 limitation in accordance with the
provisions of Treasury Regulations (S)1.1502-95T(e). APP agrees to cooperate in
the preparation, execution and filing of such election.

     (c)  APP Group Separate Returns.  APP shall prepare, or cause to be
prepared all APP Group Separate Returns. APP covenants that on or after a
Deconsolidation it will not, nor will it cause or permit any member of the APP
Group to make or change any tax election, change any accounting method, amend
any tax return or take any tax position on any tax return, take any other
action, omit to take any action, or enter into any transaction that results in
any increase in the tax liability or reduction of any Tax Asset of the ABI
Consolidated Group in respect of any Pre-Deconsolidation Tax Period, without
first obtaining the written consent of an authorized representative of ABI.

     (d)  Carrybacks.  Except to the extent otherwise consented to by ABI or
prohibited by applicable law, APP (on its own behalf and on behalf of the APP
Group) shall elect to relinquish, waive or otherwise forego all Carrybacks. In
the event that APP is prohibited by applicable law to relinquish, waive or
otherwise

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forego a Carryback (or ABI consents thereto), (i) ABI shall cooperate with APP,
at APP's expense, in seeking from the appropriate taxing jurisdiction such
Refund as reasonably would result from such Carryback, and (ii) APP shall be
entitled to any Income Tax Benefit Actually Realized by a member of the ABI
Consolidated Group (including any interest thereon received from such taxing
jurisdiction), to the extent that such Income Tax Benefit is directly
attributable to such Carryback, within 10 days after such Income Tax Benefit is
Actually Realized; provided, however, that APP shall indemnify and hold the
members of the ABI Consolidated Group harmless from and against any and all
collateral tax consequences resulting from or caused by any such Carryback,
including (but not limited to) the loss or postponement of benefit from the use
of tax attributes generated by a member of the ABI Consolidated Group (x) that
expire unutilized, but would have been utilized but for such Carryback, or (y)
the use of which is postponed to a later taxable period than the taxable period
in which such tax attributes otherwise would have been utilized but for such
Carryback. Nothing in this Agreement shall require ABI to file a claim for
refund of Federal Taxes or Combined Taxes which ABI, in its sole discretion,
determines lacks substantial authority, as defined in the Code and the Treasury
Regulations thereunder. If there is a Final Determination that results in any
change to or adjustment of an Income Tax Benefit Actually Realized by a member
of the ABI Consolidated Group that is directly attributable to a Carryback, then
ABI (or its designee) shall make a payment to APP, or APP shall make a payment
to ABI (or its designee), as may be necessary to adjust the payments between APP
and ABI (or its designee) to reflect the payments that would have been made
under this Section 3.1(d) had the adjusted amount of such Income Tax Benefit
been taken into account in computing the payments due under this Section 3.1(d).

     (e)  Refunds.  Except to the extent provided in Section 3.1(d) hereof, ABI
shall be entitled to all Refunds (and any interest thereon received from the
applicable taxing jurisdiction) in respect of Income Taxes for all Pre-
Deconsolidation Tax Periods. Except to the extent provided in Section 3.1(d),
APP shall be entitled to all Refunds (and any interest thereon received from the
applicable taxing jurisdiction) in respect of Income Taxes paid by APP with
respect to APP Group Separate Returns and attributable to Post-Deconsolidation
Tax Periods included in Combined Tax returns. A party receiving a Refund to
which another party is entitled pursuant to this Section 3.1(e) shall pay the
amount to which such other party is entitled within ten days after such Refund
is Actually Realized. ABI shall be permitted to file, and APP shall fully
cooperate with ABI in connection with, any claim for Refund in respect of an
Income Tax for which ABI is responsible pursuant to Section 2.1 (a) hereof.

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                                  ARTICLE 4.
                                MISCELLANEOUS

     4.1  Limitation of Liability.

     Neither ABI nor APP shall be liable to the other for any special, indirect,
incidental, or consequential damages of the other arising in connection with
this Agreement.

     4.2  Subsidiaries.

     (a)  Performance.  ABI agrees and acknowledges that ABI shall be
responsible for the performance of the obligations of each member of the ABI
Sub-Group hereunder applicable to such subsidiary. APP agrees and acknowledges
that APP shall be responsible for the performance by each member of the APP
Group of the obligations hereunder applicable to such member.

     (b)  Application to Present and Future Subsidiaries. This Agreement is
being entered into by ABI and APP on behalf of themselves and each member of the
ABI Sub-Group and the APP Group, respectively. This Agreement shall constitute a
direct obligation of each such member and shall be deemed to have been readopted
and affirmed on behalf of any corporation which becomes a member of the ABI Sub-
Group or the APP Group in the future. ABI shall cause each member of the ABI
Consolidated Group, and APP shall cause each member of the APP Group, to comply
fully with the terms of this Agreement. Each party shall, upon the written
request of the other, cause any of their respective group members to execute and
deliver a counterpart of this Agreement.

     4.3  Cooperation.

     (a) APP, on behalf of itself and each member of the APP Group, agrees to
provide ABI (or its designee) with such cooperation or information as ABI (or
its designee) reasonably shall request in connection with the determination of
any other calculations described in this Agreement, the preparation or filing of
any Income Tax return or claim for Refund, or the conduct of any proceeding
relating to Income Tax. Such cooperation and information shall include, without
limitation, upon reasonable notice (i) promptly forwarding copies of appropriate
notices and forms or other communications (including, without limitation,
information document requests, revenue agent's reports and similar reports,
notices of proposed adjustments and notices of deficiency) received from or sent
to any taxing jurisdiction or any other administrative, judicial or governmental
authority, (ii) providing copies of all relevant Income Tax returns, together
with accompanying schedules and related workpapers, documents relating to
rulings or other determinations by taxing authorities, and such other records
concerning the ownership and tax basis of property, or other relevant
information that APP or any member of the APP Group may possess, (iii) the
provision of such additional information and explanations of documents and
information provided under this

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Agreement (including statements, certificates and schedules delivered by either
party) as shall be reasonably requested by ABI (or its designee), (iv) the
execution of any document that may be necessary or reasonably helpful in
connection with the filing of an Income Tax return, a claim for a Refund, or in
connection with any proceeding, including such waivers, consents or powers of
attorney as may be necessary for ABI to exercise its rights under this
Agreement, and (v) the use of APP's reasonable efforts to obtain any
documentation from a governmental authority or a third party that may be
necessary or reasonably helpful in connection with any of the foregoing. Upon
reasonable notice, APP shall make its, or shall cause each member of the APP
Group to make its, employees and facilities available on a mutually convenient
basis to provide explanation of any documents or information provided hereunder.
Any information obtained under this Section 4.3(a) shall be kept confidential,
except as otherwise reasonably may be necessary in connection with the filing of
Income Tax returns or claims for Refund or in conducting any proceeding. It is
expressly the intention of the parties to this Agreement to take all actions
that shall be necessary to establish ABI as the sole agent for Income Tax
purposes with respect to all ABI consolidated Federal Tax returns and Combined
Tax returns.

     (b) ABI, on behalf of itself and each member of the ABI Sub-Group, agrees
to provide APP (or its designee) with such cooperation or information as APP (or
its designee) reasonably shall request in connection with the determination of
any other calculations described in this Agreement, the preparation or filing of
any Income Tax return or claim for Refund, or the conduct of any proceeding
relating to Income Tax. Such cooperation and information shall include, without
limitation, upon reasonable notice (i) promptly forwarding copies of appropriate
notices and forms or other communications (including, without limitation,
information document requests, revenue agent's reports and similar reports,
notices of proposed adjustments and notices of deficiency) received from or sent
to any taxing jurisdiction or any other administrative, judicial or governmental
authority, (ii) providing copies of all relevant Income Tax returns, together
with accompanying schedules and related workpapers, documents relating to
rulings or other determinations by taxing authorities, and such other records
concerning the ownership and tax basis of property, or other relevant
information that ABI or any member of the ABI Sub-Group may possess, (iii) the
provision of such additional information and explanations of documents and
information provided under this Agreement (including statements, certificates
and schedules delivered by either party) as shall be reasonably requested by APP
(or its designee), (iv) the execution of any document that may be necessary or
reasonably helpful in connection with the filing of an Income Tax return, a
claim for a Refund, or in connection with any proceeding, including such
waivers, consents or powers of attorney as may be necessary for APP to exercise
its rights under this Agreement, and (v) the use of ABI's reasonable efforts to
obtain any documentation from a governmental authority or a third party that may
be necessary or reasonably helpful in connection with any of the foregoing. Upon
reasonable notice, ABI shall make its, or shall cause each member of the ABI
Sub-Group to make its, employees and facilities available on a mutually
convenient basis to provide explanation of any documents

                                       11
<PAGE>

or information provided hereunder. Any information obtained under this Section
4.3(b) shall be kept confidential, except as otherwise reasonably may be
necessary in connection with the filing of Income Tax returns or claims for
Refund or in conducting any proceeding. Notwithstanding any other provision of
this Agreement, neither APP, nor any of member of the APP Group shall have any
right to receive or obtain any information relating to Income Taxes of ABI or
the ABI Consolidated Group other than (i) information relating solely to APP or
a member of the APP Group, and (ii) information required to be provided pursuant
to Section 2.1(f) hereof.

     4.4  Retention of Records.

     APP agrees to retain all Income Tax returns, related schedules and
workpapers, and all material records and other documents as required under Code
Section 6001 and the Treasury Regulations promulgated thereunder (and any
similar provision of state, local, or foreign Income Tax law) existing on the
date hereof or created in respect of (i) any taxable period that ends on or
before or includes the Deconsolidation Date or (ii) any taxable period that may
be subject to a claim hereunder, until the later of (x) the expiration of the
statute of limitations (including extensions) for the taxable periods to which
such Income Tax returns and other documents relate and (y) the Final
Determination of any payments that may be required in respect of such taxable
periods under this Agreement. ABI shall notify APP whenever the applicable
statute of limitations for any taxable period, including extensions, expires or,
if sooner or later, as the case may be, whenever a Final Determination has
occurred with respect to such taxable period.  From and after the end of the
period described in the first sentence of this Section 4.4, if APP wishes to
dispose of any such records and documents, then APP shall provide written notice
thereof to ABI and shall provide ABI the opportunity to take possession of any
such records and documents within 90 days after such notice is delivered, at
ABI's sole cost and expense; provided, however, that if ABI does not, within
such 90-day period, confirm its intention to take possession of such records and
documents, APP may destroy or otherwise dispose of such records and documents.

     4.5  Agent.

     Each member of the APP Group hereby irrevocably appoints ABI as its agent
and limited attorney-in-fact to take any action as ABI may deem necessary or
appropriate to effect Section 2.1 including, without limitation, those actions
specified in Treasury Regulation (S)1.1502-77(a).

     4.6  Amendments.

     This Agreement may not be amended or terminated orally, but only by a
writing duly executed by or on behalf of the parties hereto.  Any such amendment
shall be validly and sufficiently authorized for purposes of this Agreement if
it is signed on behalf of ABI and APP by any of their respective presidents or
vice presidents.

                                       12
<PAGE>

     4.7  Resolution of Disputes.

     Any disputes between the parties concerning the calculation of amounts,
allocation, or attribution of costs, or any Tax Asset or Income Tax Benefit, or
similar accounting matters shall be resolved in accordance with ABI's
interpretation of this Agreement, unless APP shall provide ABI with an opinion
of a nationally recognized public accounting firm to the effect that such
interpretation is unreasonable.  If such opinion takes the position that ABI's
interpretation of this Agreement is unreasonable, and the parties, conferring in
good faith, cannot thereafter successfully resolve such dispute in a timely
manner, then either party may submit the matter to binding arbitration in
accordance with the Rules of Commercial Arbitration of the American Arbitration
Association.  Judgment upon the award rendered by the arbitrator(s) may be
entered in any court having jurisdiction thereof.  Such arbitration shall occur
in New York City pursuant to Article VIII of the Separation Agreement entered
into between the parties as of the date hereof , unless the otherwise agreed by
the parties.  The arbitrator(s) may, in such proceeding, award attorney's fees
and costs to the prevailing party.

     4.8  Severability.

     If any provision of this Agreement or the application of any such provision
to any party or circumstances shall be determined by any court of competent
jurisdiction to be invalid, illegal, or unenforceable to any extent, the
remainder of this Agreement or such provision or the application of such
provision to such party or circumstances, other than those to which it is so
determined to be invalid, illegal, or unenforceable, shall remain in full force
and effect to the fullest extent permitted by law and shall not be affected
thereby, unless such a construction would be unreasonable.

     4.9  Notices.

     All notices and other communications required or permitted hereunder shall
be in writing, shall be deemed duly given upon actual receipt, and shall be
delivered (a) in person, (b) by registered or certified mail, postage prepaid,
return receipt requested, or (c) by facsimile or other generally accepted means
of electronic transmission (provided that a copy of any notice delivered
pursuant to this clause (c) shall also be sent pursuant to clause (a) or (b)),
addressed as follows:

     (1)  If to ABI to:

          American BioScience, Inc.
          2730 Wilshire Boulevard, #110
          Santa Monica, CA  90403
          Fax:  (310) 998-8553

          Attn:  President

                                       13
<PAGE>

     (2)  If to APP, to:

          American Pharmaceutical Partners, Inc.
          10866 Wilshire Blvd., Suite 1270
          Los Angeles, CA  90024
          Fax:  (310) 470-7472

          Attn:  Chief Financial Officer

     4.10  Expenses.

     Unless otherwise expressly provided in this Agreement, each party shall
bear any and all expenses that arise from its respective obligations under this
Agreement.

     4.11  Further Assurances.

     ABI and APP shall execute, acknowledge, and deliver, or cause to be
executed, acknowledged, and delivered, such instruments and take such other
actions as may be necessary or advisable to carry out their obligations under
this Agreement and under any exhibit, document, or other instrument delivered
pursuant hereto.

     4.12  Entire Agreement.

     This Agreement constitutes the entire understanding of the parties hereto
with respect to the subject matter hereof.

     4.13  Successors.

     This Agreement shall be binding upon and inure to the benefit of any
successor, by merger, acquisition of assets, or otherwise, to any of the parties
hereto (including but not limited to any successor of ABI and APP succeeding to
the tax attributes of such party under Section 381 of the Code), to the same
extent as if such successor had been an original party hereto.

     4.14  Authorization, etc.

     Each of the parties hereto hereby represents and warrants that it has the
power and authority to execute, deliver, and perform this Agreement, that this
Agreement has been duly authorized by all necessary corporate action on the part
of such party, that this Agreement constitutes a legal, valid and binding
obligation of each such party, and that the execution, delivery and performance
of this Agreement by such party does not contravene or conflict with any
provision of law or of its charter or bylaws or any agreement instrument or
order binding on such party.

                                       14
<PAGE>

     4.15  Titles and Headings.

     Titles and headings to sections herein are for convenience and reference
only and are not intended to be a part, or to affect the meaning or
interpretation, of this Agreement.

     4.16  Governing Law.

     This Agreement shall be governed by and construed in accordance with the
laws of the State of California.

     4.17  Counterparts.

     This Agreement may be executed in any number of counterparts, each of which
shall be deemed an original, but all of which together shall constitute one and
the same Agreement.

     IN WITNESS WHEREOF, each of the parties hereto has caused this agreement to
be executed by a duly authorized officer as of the date first above written.

American BioScience, Inc.                 American Pharmaceutical Partners, Inc.

   /s/ Patrick Soon-Shiong, M.D.             /s/ Patrick Soon-Shiong, M.D.
By______________________________          By______________________________
  Title: President                          Title: President

                                       15<PAGE>

                                                                    Exhibit 10.9

                                   AGREEMENT

          THIS AGREEMENT (this "Agreement") is entered into as of July 25,  2001
                                ---------
between AMERICAN BIOSCIENCE, INC., a California corporation ("ABI"), and
AMERICAN PHARMACEUTICAL PARTNERS, INC., a California corporation ("APP").

                                R E C I T A L S
                                - - - - - - - -

     A.   ABI owns approximately 85% of the equity securities of APP, and
certain officers and directors of APP are officer or directors, or both, of ABI.

     B.   ABI is engaged, or proposes to be engaged, in the ABI Operations (as
defined below), and APP is engaged, or proposes to be engaged, in the APP
Operations (as defined below); in certain respects, the ABI Operations may be
similar to, or may compete with, the APP Operations.

     C.   It is anticipated that the parties may enter a license agreement (the
"APP/ABI License Agreement"), pursuant to which ABI may license to APP certain
 -------------------------
rights with respect to certain of ABI's products.

     D.   Each party hereto desires to confirm and clarify in writing its
agreements and understandings as to the operations and activities of the other
party (and certain of their respective officers and directors).

     E.   The board of directors of each party hereto have approved this
Agreement.

                                   AGREEMENT
                                   ---------

     NOW, THEREFORE, in consideration of the premises, the mutual covenants
contained herein and other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties hereto hereby agree as
follows:

     1.   Definitions. Unless otherwise defined herein, the capitalized terms
          -----------
used in this Agreement shall have the meanings assigned to such terms in this
Section 1.

          "ABI Board" shall mean the board of directors of ABI.
           ---------

                                       1

<PAGE>

          "ABI Business Opportunity" shall mean any business opportunity that
           ------------------------
may be presented to either Dual Officer relating to the development,
manufacture, and/or distributions of Proprietary Products that are in pre-
clinical, Phase I or Phase II stage of development at the time the opportunity
is presented to such Dual Officer.

          "ABI Operations" shall mean the research, development, manufacture,
           --------------
marketing, distribution or sale of Proprietary Products; including, without
                                                         ----------
limitation, (i) the Proprietary Products currently being developed by ABI, (ii)
Proprietary Products that may be acquired and/or developed by ABI after the date
of this Agreement through research, acquisition, license or otherwise and (iii)
any Proprietary Products that are similar to or compete with any generic or
other pharmaceutical products that are marketed or sold by APP; but excluding
                                                                    ---------
the research, development, manufacture, marketing, distribution or sale of
generic pharmaceutical products.

          "APP Board" shall man the board of directors of APP.
           ---------

          "APP Business Opportunity" shall mean any business opportunity that
           ------------------------
may be presented to either Dual Officer relating to the development,
manufacture, and/or distributions of (i) generic biological or pharmaceutical
products, or (ii) Proprietary Products that have completed Phase II or have
entered into Phase III stage of development at the time the opportunity is
presented to such Dual Officer.

          "APP Operations" shall mean
           --------------

               (i)   the research, development, manufacture, marketing,
distribution or sale of generic biological or pharmaceutical products;
including, without limitation, (x) the generic pharmaceutical products currently
---------
being marketed and sold by APP, (y) the generic pharmaceutical products covered
by ANDAs that have been filed by, or currently proposed to be filed by APP, and
(z) any generic biological or pharmaceutical products that are similar to or
compete with any of the products that are currently being developed by ABI;

               (ii)  the activities of APP contemplated by the APP/ABI License
Agreement (or under any subsequent written agreement between ABI and APP);

               (iii) the acquisition from third parties of development,
manufacturing or distribution rights to branded pharmaceutical products; or

               (iv)  the acquisition of companies that are developing branded
pharmaceutical products and the continued development of those products.

                                       2

<PAGE>

          "Dual Officers" shall mean (i) Patrick Soon-Shiong, (ii) Derek Brown
           --------------
and (iii) any other person who may be designated as a Dual Officer for purposes
of this Agreement by the APP Board and the ABI Board.

          "Proprietary Products" shall mean branded, proprietary and/or novel
           --------------------
delivery forms of biological or branded, proprietary and/or novel delivery forms
of pharmaceutical products.

     2.   Acknowledgements and Agreements of APP. APP acknowledges to and agrees
          --------------------------------------
with ABI as follows (subject to Section 4 hereof):

          a.   The APP Board has determined that APP currently does not intend
to engage in any of the ABI Operations (except to the extent that such
activities are also included in APP Operations), and none of the ABI Operations
constitutes a "business opportunity" of APP (even if ABI's conduct of the ABI
Operations competes with the APP Operations or otherwise adversely affects APP);
provided, that nothing in this Agreement shall prohibit the APP Board from
--------
subsequently determining to engage in the ABI Operations or any other activity.

          b.   Except as set forth on Exhibit A hereto or may otherwise be
agreed in writing by the parties, the Dual Officers may (i) engage, on behalf of
ABI, in the ABI Operations, (ii) devote such time and effort to the ABI
Operations as they deem appropriate, (iii) apportion their business time and
effort between ABI and APP in such manner as they deem appropriate, in each case
without any liability or obligation to APP or its shareholders; provided, that
                                                                --------
nothing in this Agreement shall affect the right of the board of directors of
APP to remove the Dual Officers as officers of APP at any time.

          c.   Except as may be required under the APP/ABI License Agreement, no
Dual Officer shall have any obligation to disclose to APP (or the directors of
APP) any information regarding the ABI Operations.

          d.   Each Dual Officer may receive a salary or other remuneration from
either or both of APP and ABI.

          e.   To the extent that a Dual Officer presents an ABI Business
Opportunity to the ABI Board without first presenting that ABI Business
Opportunity to the APP Board, such ABI Business Opportunity shall not be deemed
to be a "corporate opportunity" of APP; except that if the ABI Board declines
                                        ------ ----
the ABI Business Opportunity, the Dual Officer may offer such ABI Business
Opportunity to the APP Board.

                                       3

<PAGE>

          f.   Except as may otherwise be agreed to in writing by the parties
(in the sole discretion of their respective boards of directors), neither ABI
nor any of its shareholders shall have any duty or obligation to provide any
financial or other resources to APP.

     3.   Acknowledgements and Agreements of ABI. ABI acknowledges to and agrees
          --------------------------------------
with APP as follows (subject to Section 4 hereof):

          a.   The board of directors of ABI has determined that ABI currently
does not intend to engage (except indirectly through APP or to the extent that
such activities are also included as ABI Operations) in any of the APP
Operations, and none of the APP Operations constitutes a "business opportunity"
of ABI (even if APP's conduct of the APP Operations competes with the ABI
Operations or otherwise adversely affects ABI); provided, that nothing in this
                                                --------
Agreement shall prohibit the ABI Board from subsequently determining to engage
in the APP Operations or any other activity.

          b.   Except as set forth on Exhibit A hereto or may otherwise be
agreed in writing by the parties, the Dual Officers may (i) engage, on behalf of
APP, in the APP Operations, (ii) devote such time and effort to the APP
Operations as they deem appropriate, and (iii) apportion their business time and
effort between ABI and APP in such manner as they deem appropriate, in each case
without any liability or obligation to ABI or its shareholders; provided, that
                                                                --------
nothing in this Agreement shall affect the right of the board of directors of
ABI to remove the Dual Officers as officers of ABI at any time.

          c.   Except as may be required under any APP/ABI License Agreement, no
Dual Officer shall have any obligation to disclose to ABI (or the directors of
ABI) any information regarding the APP Operations.

          d.   Each Dual Officer may receive a salary or other remuneration from
either or both of APP and ABI.

          e.   To the extent that a Dual Officer presents an APP Business
Opportunity to the APP Board without first presenting that APP Business
Opportunity to the ABI Board, such APP Business Opportunity shall not be deemed
to be a "corporate opportunity" of ABI; except that if the APP Board declines
                                        ------ ----
the APP Business Opportunity, the Dual Officer may offer such APP Business
Opportunity to the ABI Board.

          f.   Except as may otherwise be agreed to in writing by the parties
(in the sole discretion of their respective boards of directors), neither APP
nor any of its shareholders shall have any duty or obligation to provide any
financial or other resources to ABI.

                                       4

<PAGE>

     4.   Releases.
          --------

          a.   Effective as of the date hereof, APP, for itself and for all
others who may claim through it, knowingly and voluntarily releases, ABI and
each Dual Officer from any claim arising out of the pursuit by ABI of an y
business opportunity conceived by a Dual Officer for the benefit of ABI or
otherwise presented to ABI by a Dual Officer from APP's incorporation through
the date of this Agreement.

          b.   Effective as of the date hereof, ABI, for itself and for all
others who may claim through it, knowingly and voluntarily releases, APP and
each Dual Officer from any claim arising out of the pursuit by APP of any
business opportunity conceived by a Dual Officer for the benefit of APP or
otherwise presented to APP by a Dual Officer from APP's incorporation through
the date of this Agreement.

     5.   Limitations.
          -----------

          a.   Nothing in Section 2 above shall constitute an authorization or
approval by APP of any use or disclosure by ABI (or any Dual Officer on behalf
of or for the benefit of ABI) of any trade secret or confidential information of
APP.

          b.   Nothing in Section 3 above shall constitute an authorization or
approval by ABI of any use or disclosure by APP (or any Dual Officer on behalf
of or for the benefit of APP) of any trade secret or confidential information of
ABI.

     6.   Governing Law.  This Agreement shall be governed by and construed
          -------------
and enforced in accordance with the internal substantive laws (and not the laws
of conflicts) of the State of California.

     7.   Entire Agreement. This Agreement constitutes the whole agreement of
          ----------------
the parties hereto in reference to any of the matters or things herein provided
for or hereinabove discussed all prior agreements, promises, representations and
understandings relative thereto being herein merged.

     8.   Amendments; Waivers.  This Agreement may be amended, modified,
          -------------------
superseded, canceled, renewed or extended and the terms or covenants of this
Agreement may be waived only by a written instrument executed by the parties to
this Agreement or, in the case of a waiver, by the party waiving compliance.
The failure of any party at any time or times to require performance of any
provision of this Agreement shall in no manner affect the right at a later time
to enforce the same.  No waiver by any party of the breach of any term or
provision contained in this Agreement, whether by conduct or otherwise, in any
one or more instances, shall be deemed to be, or construed as, a further

                                       5

<PAGE>

or continuing waiver of any such breach, or a waiver of the breach of any other
term or covenant contained in this Agreement.

     9.   Severability.  Any provision of this Agreement that is prohibited or
          ------------
unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective
to the extent of such prohibition or unenforceability without invalidating the
remaining provisions hereof, and any such prohibition or unenforceability in any
jurisdiction shall not invalidate or render unenforceable such provision in any
other jurisdiction.

    10.   Headings. The headings of the Sections and paragraphs of this
          --------
Agreement have been inserted for convenience of reference only and do not
constitute a part of this Agreement.

     11.  Attorneys' Fees. If either party to this Agreement seeks to enforce
          ---------------
his or its rights under this Agreement, the prevailing party shall be entitled
to recover reasonable fees, costs and expenses incurred in connection therewith
including, without limitation, the fees, costs and expenses of attorneys,
accountants and experts, whether or not litigation is instituted, and including
such fees, costs and expenses of appeals.

     12.  Arbitration. At the option of any party hereto, any and all disputes
          -----------
or controversies, whether of law or fact and of any nature whatsoever arising
from or respecting this Agreement, shall be decided by binding arbitration in
accordance with Title 9 of the United States Code and the Commercial Arbitration
Rules of the American Arbitration Association (the "Association"). If the
parties are unable to agree upon a single arbitrator, the arbitrator shall be a
single, independent arbitrator selected by the Association. Arbitration shall
take place at Los Angeles, California, or any other location mutually agreeable
to the parties. The decision of the arbitrator shall be final and binding upon
all parties hereto and all persons claiming under and through them and judgment
thereon may be entered by any court of competent jurisdiction. The fees and
expenses of the arbitrator shall be paid equally by the parties to such
arbitration.

     13.  Term. The term of the Agreement runs from execution through December
          ----
31, 2013.

                           [SIGNATURE PAGE FOLLOWS]

                                       6

<PAGE>

IN WITNESS WHEREOF, the parties have executed this Agreement on the day and year
                            first indicated above.

                      AMERCIAN BIOSCIENCE, INC.

                      By: /s/ Patrick Soon-Shiong, M.D.
                         ---------------------------------

                      Its: President
                          --------------------------------

                      AMERICAN PHARMACEUTICAL PARTNERS, INC.

                      By: /s/ Jeffery M. Yordon
                         ---------------------------------

                      Its: Co-Chief Operating Officer
                          --------------------------------

                                       7

<PAGE>

                                   EXHIBIT A

                   RESTRICTIONS/OBLIGATIONS OF DUAL OFFICERS
                   -----------------------------------------

     1.   APP and ABI acknowledge and agree that:

          (i)   it is the expectation of APP that for a period of 6 months after
the date hereof (or, if earlier, until the date he is no longer and officer or
director of APP), Patrick Soon Shiong shall devote at least an average of 25
hours per week (as determined on a quarterly basis) (subject to absences for
illness or disabilities) to the APP Operations (which for this purpose shall
include any attention to the development or commercialization of any ABI
technologies or products which have been licensed to APP under the ABI/APP
License Agreement), and Dr. Soon-Shiong may in his discretion to devote a
greater time to the APP Operations (but is not expected by APP to spend such
greater time) and

          (ii)  Dr Soon-Shiong may devote business time and effort to APP in a
manner consistent with clause (i.).

     2.   APP and ABI acknowledge and agree that:

          (i)   it is the expectation of APP that for so long as Derek Brown is
an officer or director of APP, he shall devote at least an average of 35 hours
per week (as determined on a quarterly basis) (subject to absences for illness
or disabilities) to the APP Operations (which for this purpose shall include any
attention to the development or commercialization of any ABI technologies or
products which have been licensed to APP under the ABI/APP License Agreement),
and Mr. Brown may in his discretion to devote a greater time to the APP
Operations (but is not expected by APP to spend such greater time) and

          (ii)  Mr. Brown's may devote business time and effort to APP in a
manner consistent with clause (i).

                                       8

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