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COMDISCO                                                           17-M00148-SG
A Technology Services Company                             MASTER LEASE AGREEMENT

MASTER LEASE AGREEMENT dated as of SEPTEMBER 22, 2000 by and between COMDISCO
LABORATORY AND SCIENTIFIC GROUP, A DIVISION OF COMDISCO, INC. ("Lessor), and
NEOTHERAPEUTICS, INC. ("Lessee").

IN CONSIDERATION of the mutual agreements described below, the parties agree as
follows (all capitalized terms are defined in Section 14.12):

1.  PROPERTY LEASED.

    Lessor leases to Lessee all of the Equipment described on each Schedule. In
the event of a conflict, the terms of a Schedule prevail over this Master Lease.

2.  TERM.

    On the Commencement Date Lessee will be deemed to accept the Equipment, will
be bound to its rental obligations for each item of Equipment and the term of a
Schedule will begin and continue through the Initial Term and thereafter until
terminated by either party upon prior written notice received during the Notice
Period. No termination may be effective prior to the expiration of the Initial
Term.

3.  RENT AND PAYMENT.

    Rent is due and payable in advance, in immediately available funds, on the
first day of each Rent Interval to the payee and at the. location specified in
Lessor's invoice. Interim Rent is due and payable when Invoiced. If any payment
Is not made when due, Lessee will pay interest at the Overdue Rate.

4.  SELECTION AND WARRANTY AND DISCLAIMER OF WARRANTIES.

    4.1 Selection. Lessee acknowledges that it has selected the Equipment and
disclaims any reliance upon statements made by the Lessor.

    4.2 Warranty and Disclaimer of Warranties. Lessor warrants to Lessee that,
so long as Lessee is not in default, Lessor will not disturb Lessee's quiet and
peaceful possession, and unrestricted use of the Equipment. To the extent
permitted by the manufacturer, Lessor assigns to Lessee during the term of the
Schedule any manufacturers warranties for the Equipment. LESSOR MAKES NO OTHER
WARRANTY, EXPRESS OR IMPLIED AS TO ANY MATTER WHATSOEVER, INCLUDING, WITHOUT
LIMITATION, THE MERCHANTABILITY OF THE EQUIPMENT OR ITS FITNESS FOR A PARTICULAR
PURPOSE. Lessor is not responsible for any liability, claim, loss, damage or
expense of any kind (including strict liability in tort) caused by the Equipment
except for any loss or damage caused by the negligent acts of Lessor. In no
event is Lessor responsible for special, incidental or consequential damages.

5.  TITLE AND ASSIGNMENT.

    5.1 Title. Lessee holds the Equipment subject and subordinate to the rights
of the Owner, Lessor, any Assignee and any Secured Party. Lessee authorizes
Lessor, as Lessee's agent to prepare, execute and file in Lessee's name
precautionary Uniform Commercial Code financing statements showing the interest
of the Owner, Lessor, and any Assignee or Secured Party in the Equipment and to
insert serial numbers in Schedules as appropriate. Except as provided in
Sections 5.2 and 7.2. Lessee will, at its expense, keep the Equipment free and
clear from any liens or encumbrances of any kind (except any caused by Lessor)
and will indemnify and hold Lessor, Owner, any Assignee and Secured Party
harmless from and against any loss caused by Lessee's failure to do so.

    5.2 Relocation or Sublease. Upon prior written notice, Lessee may relocate
the Equipment to any location within the continental United States provided (i)
the Equipment will not be used by an entity exempt from federal income tax, (ii)
all additional costs (including any administrative fees, additional taxes and
insurance coverage) are reconciled and promptly paid by Lessee. Lessee may
sublease the Equipment upon the reasonable consent of the Lessor and the Secured
Party and provided Lessee meets the requirements under (i) and (ii) above. No
relocation or sublease will relieve Lessee from any of its obligations under
this Master Lease and the applicable Schedule.

    5.3 Assignment by Lessor. The terms and conditions of each Schedule have
been fixed by Lessor in order to permit Lessor to sell and/or assign or transfer
its interest or grant a security interest in each Schedule and/or the Equipment
to a Secured Party or Assignee. In that event the term Lessor *11 mean the
Assignee and any Secured Party. However, any assignment sale, or other transfer
by Lessor will not relieve Lessor of its obligations to Lessee and will not
materially change Lessee's duties or materially increase the burdens or risks
imposed on Lessee. The Lessee consents to and will acknowledge such assignments
in a written notice given to Lessee. Lessee also agrees that:

        (a) The Secured Party will be entitled to exercise all of Lessor's
            rights, but will not be obligated to perform any of the obligations
            of Lessor. The Secured Party will not disturb Lessee's quiet and
            peaceful possession and unrestricted use of the Equipment so long as
            Lessee is not In default and the Secured Party continues to receive
            all Rent payable under the Schedule;

        (b) Lessee will pay all Rent and all other amounts payable to the
            Secured Party, despite any defense or claim which it has against
            Lessor. Lessee reserves its right to have recourse directly against
            Lessor for any defense or claim; and

        (c) Subject to and without impairment of Lessee's leasehold rights in
            the Equipment, Lessee holds the Equipment for the Secured Party to
            the extent of the Secured Party's rights in that Equipment.

6.  NET LEASE AND TAXES AND FEES.

    6.1 Net Lease. Each Schedule constitutes a net lease. Lessee's obligation to
pay Rent and all other amounts is absolute and unconditional and is not subject
to any abatement reduction, set-off, defense, counterclaim, interruption,
deferment or recoupment for any reason whatsoever.

    6.2 Taxes and Fees. Lessee will pay when due or reimburse Lessor for all
taxes, fees or any other charges (together with any related interest, or
penalties not arising from the negligence of Lessor) accrued for or arising
during the term of each Schedule against Lessor, Lessee or the Equipment by any
governmental authority (except only Federal, state and local taxes on the
capital or the net income of Lessor). Lessor will file all personal property tax
returns for the Equipment and pay all property taxes due. Lessee will reimburse
Lessor for property taxes within thirty (30) days of receipt of an invoice.

7.  CARE, USE AND MAINTENANCE, ATTACHMENTS AND RECONFIGURATIONS, AND INSPECTION
    BY LESSOR.

    7.1 Care, Use and Maintenance. Lessee will operate the Equipment in
accordance with all laws and regulations and maintain the Equipment in good
operating order and appearance, protect the Equipment from deterioration, other
than normal wear and tear, and will not use the Equipment for any purpose other
than that for which it was designed. If commercially available, Lessee will
maintain in force a standard maintenance contract with the manufacturer of the
Equipment and upon request will provide Lessor with a complete copy of that
contract. With Lessor's prior written consent Lessee may have the Equipment
maintained by a party other than the manufacturer. Lessee agrees to pay any
costs necessary for the manufacturer to bring the Equipment to original
Equipment specifications at origination of lease, normal wear and tear excepted,
and to re-certify the Equipment as eligible for manufacturer's maintenance at
the expiration of lease term. The lease term will continue upon the same terms
and conditions until recertification has been obtained.

    7.2 Attachments and Reconfigurations. Upon Lessor's prior written consent,
Lessee may reconfigure and install Attachments on the Equipment. In the event of
such a Reconfiguration or Attachment, Lessee shall, upon return of the
Equipment, at Ks expense, restore the Equipment to the original configuration
specified on the Schedule in accordance with the manufacturer's specifications
and in the same operating order, repair and appearance as when installed (normal
wear and tear excluded). Alternatively, with Lessor's prior written consent
which will not be unreasonably withheld, Lessee may return the Equipment with
any Attachment or upgrade.

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    7.3 Inspection by Lessor. Upon request, Lessee, during reasonable business
hours and subject to Lessee's security requirements, will make the Equipment and
its related log and maintenance records, instruction manuals, published
statements of capabilities and technical specifications and certification,
qualification and calibration reports available to Lessor for inspection.

8.  REPRESENTATIONS AND WARRANTIES OF LESSEE.

    Lessee represents and warrants that for the Master Lease and each Schedule:

        (a) The execution, delivery and performance of the Lessee have been duly
            authorized by all necessary corporate action;

        (b) The individual executing was duly authorized to do so;

        (c) The Master Lease and each Schedule constitute legal, valid and
            binding agreements of the Lessee enforceable in accordance with
            their terms;

        (d) The Equipment is personal property and when subjected to use by the
            Lessee will not be or become fixtures under applicable law, and

        (e) The Equipment will be for laboratory use only and will not be used
            in a clinical environment on patients.

9.  DELIVERY AND RETURN OF EQUIPMENT

    Lessee assumes the full expense of transportation of the Equipment to its
initial location, Installation. deinstallation, and return to a location within
the continental United States (including without limitation the expense of
in-transit Insurance) all pursuant to Lessor's instructions and manufacturer's
specifications. Regarding deinstallation, Lessee will assure that the Equipment
Is deinstalled by the manufacturer in accordance with the manufacturer's
recommended procedures and decontaminated for transport In accordance with any
Environmental Law. and returned with a Verification of Decontamination In the
same operating order. repair, condition and appearance as when originally
installed (less normal wear and tear and depreciation) meeting all original
equipment manufacturers specifications for continued manufacturer's maintenance,
and accompanied by all associated documents, manuals (including, but not limited
to, those listed in Section 7.3), spare parts and accessories and maintenance
records for the duration of the Schedule. In connection with deinstallation,
Lessee will assure that any Contaminant removed from the Equipment will be
removed and transported by a licensed waste removal transporter.

10. LABELING.

    Upon request, Lessee will mark the Equipment indicating Lessor's interest.
Lessee will keep all Equipment free from any other marking or labeling which
might be interpreted as a claim of ownership.

11. INDEMNITY.

    Lessee will indemnify and hold Lessor, any Assignee and any Secured Party
harmless from and against any and all claims, costs, expenses, damages and
liabilities, Including reasonable attorneys' fees, arising out of the ownership
(for strict liability in tort only), selection, possession, leasing, operation,
control, use, maintenance, delivery, return or other disposition of the
Equipment Including the handling or disposal of the Contaminants. However,
Lessee is not responsible to a party indemnified hereunder for any claims,
costs, expenses, damages and liabilities occasioned by the negligent acts of
such Indemnified party. Lessee agrees to carry death, bodily injury and property
damage liability insurance during the term of the Master Lease in amounts and
against risks customarily insured against by the Lessee on similar equipment
owned by It Any amounts received by Lessor under that insurance will be credited
against Lessee's obligations under this Section.

12. RISK OF LOSS.

    Effective upon delivery and until the Equipment is returned, Lessee relieves
Lessor of responsibility for all risks of physical damage to or loss or
destruction of the Equipment. Lessee will carry casualty insurance for each item
of Equipment In an amount not less than the Casualty Value. All policies for
such insurance will name the Lessor and any Secured Party as additional insured
and as loss payee, and will provide for at least thirty (30) days prior written
notice to the Lessor of cancellation or expiration. The Lessee will furnish
appropriate evidence of such insurance. Lessee shall promptly repair any damaged
item of Equipment unless such Equipment has offered a Casualty Loss. Within
fifteen (15) days of a Casualty Loss, Lessee will provide written notice of that
loss to Lessor and Lessee will, at Lessors option, either (a) replace the item
of Equipment with Like Equipment and marketable title to the Like Equipment will
automatically vest in Lessor or (b) pay the Casualty Value and after that
payment and the payment of all other amounts due and owing, Lessee's obligation
to pay further Rent for the item of Equipment will cease.

13. DEFAULT, REMEDIES AND MITIGATION.

    13.1 Default. The occurrence of any one or more of the following Events of
Default constitutes a default under a Schedule:

        (a) Lessee's failure to pay Rent or other amounts payable by Lessee when
            due If that failure continues for ten (10) days after written
            notice; or

        (b) Lessee's failure to perform any other term or condition of the
            Schedule or the material inaccuracy of any representation or
            warranty made by the Lessee in the Schedule or in any document or
            certificate furnished to the Lessor hereunder if that failure or
            inaccuracy continues for fifteen (15) days after written notice; or

        (c) An assignment by Lessee for the benefit of its creditors, the
            failure by Lessee to pay Its debts when due, the insolvency of
            Lessee, the filing by Lessee or the filing against Lessee of any
            petition under any bankruptcy or Insolvency law or for the
            appointment of a trustee or other officer with similar powers, the
            adjudication of Lessee as Insolvent, the liquidation of Lessee, or
            the taking of any action for the purpose of the foregoing; or

        (d) The occurrence of an Event of Default under any Schedule or other
            agreement between Lessee and Lessor or its Assignee or Secured
            Party.

    13.2 Remedies. Upon the occurrence of any of the above Events of Default,
Lessor, at its option, may:

        (a) enforce Lessee's performance of the provisions of the applicable
            Schedule by appropriate court action in law or in equity;

        (b) recover from Lessee any damages and or expenses, Including Default
            Costs;

        (c) with notice and demand, recover all sums due and accelerate and
            recover the present value of the remaining payment stream of all
            Rent due under the defaulted Schedule (discounted at the same rate
            of interest at which such defaulted Schedule was discounted with a
            Secured Party plus any prepayment fees charged to Lessor by the
            Secured Party or, if there is no Secured Party, then discounted at
            6%) together with all Rent and other amounts currently due as
            liquidated damages and not as a penalty;

        (d) with notice and process of law and in compliance with Lessee's
            security requirements, Lessor may enter on Lessee's premises to
            remove and repossess the Equipment without being liable to Lessee
            for damages due to the repossession, except those resulting from
            Lessor's. its assignees', agents' or representatives' negligence;
            and

        (e) pursue any other remedy permitted by law or equity.

    The above remedies, In Lessors discretion and to the extent permitted by
law, are cumulative and may be exercised successively or concurrently.

    13.3 Mitigation. Upon return of the Equipment pursuant to the terms of
Section 13.2, Lessor will use its best efforts in accordance with its normal
business procedures (and without obligation to give any priority to such
Equipment) to mitigate Lessors damages as described below. EXCEPT AS


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SET FORTH IN THIS SECTION, LESSEE HEREBY WAIVES ANY RIGHTS NOW OR HEREAFTER
CONFERRED BY STATUTE OR OTHERWISE WHICH MAY REQUIRE LESSOR TO MITIGATE ITS
DAMAGES OR MODIFY ANY OF LESSOR'S RIGHTS OR REMEDIES STATED HEREIN. Lessor may
sell, lease or otherwise dispose of all or any part of the Equipment at a public
or private sale for cash or credit with the privilege of purchasing the
Equipment. The proceeds from any sale, lease or other disposition of the
Equipment are defined as either

        (a) if sold or otherwise disposed of, the cash proceeds less the Fair
            Market Value of the Equipment at the expiration of the Initial Term
            less the Default Costs; or

        (b) if leased, the present value (discounted at three points over the
            prime rate as referenced in the Wall Street Journal at the time of
            the mitigation) of the rentals for a term not to exceed the Initial
            Term, less the Default Costs.

    Any proceeds will be applied against liquidated damages and any other sums
due to Lessor from Lessee. However. Lessee is liable to Lessor for, and Lessor
may recover, the amount by which the proceeds are less than the liquidated
damages and other sums due to Lessor from Lessee.

14. ADDITIONAL PROVISIONS.

    14.1 Entire Agreement. This Master Lease and associated Schedules supersede
all other oral or written agreements or understandings between the parties
concerning the Equipment including, for example, purchase orders. ANY AMENDMENT
OF THIS MASTER LEASE OR A SCHEDULE, MAY ONLY BE ACCOMPLISHED BY A WRITING SIGNED
BY THE PARTY AGAINST WHOM THE AMENDMENT IS SOUGHT TO BE ENFORCED.

    14.2 No Waiver. No action taken by Lessor or Lessee shall be deemed to
constitute a waiver of compliance with any representation, warranty or covenant
contained in this Master Lease or a Schedule. The waiver by Lessor or Lessee of
a breach of any provision of this Master Lease or a Schedule will not operate or
be construed as a waiver of any subsequent breach.

    14.3 Binding Nature. Each Schedule Is binding upon, and inures to the
benefit of Lessor and its assigns. LESSEE MAY NOT ASSIGN ITS RIGHTS OR
OBLIGATIONS.

    14.4 Survival of Obligations. All agreements, obligations including, but not
limited to those arising under Section 6.2, representations and warranties
contained in this Master Lease, any Schedule or in any document delivered In
connection with those agreements are for the benefit of Lessor and any Assignee
or Secured Party and survive the execution, delivery, expiration or termination
of this Master Lease.

    14.5 Notices. Any notice, request or other communication to either party by
the other will be given in writing and deemed received upon the earlier of
actual receipt or three days after mailing if mailed postage prepaid by regular
or airmail to Lessor (to the attention of `Lease Administrator) or Lessee, at
the address set out in the Schedule or, one day after It is sent by courier or
facsimile transmission if receipt is verified by the receiving party.

    14.6 Applicable Law. THIS MASTER LEASE HAS BEEN, AND EACH SCHEDULE WILL HAVE
BEEN MADE, EXECUTED AND DELIVERED IN THE STATE OF ILLINOIS AND WILL BE GOVERNED
AND CONSTRUED FOR ALL PURPOSES IN ACCORDANCE WITH THE LAWS OF THE STATE OF
ILLINOIS WITHOUT GIVING EFFECT TO CONFLICT OF LAW PROVISIONS. NO RIGHTS OR
REMEDIES REFERRED TO IN ARTICLE 2A OF THE UNIFORM COMMERCIAL CODE WILL BE
CONFERRED ON LESSEE UNLESS EXPRESSLY GRANTED IN THIS MASTER LEASE OR A SCHEDULE.

    14.7 Severability. If any one or more of the provisions of this Master Lease
or any Schedule Is for any reason held Invalid, illegal or unenforceable, the
remaining provisions of this Master Lease and any such Schedule will be
unimpaired, and the invalid, illegal or unenforceable provision replaced by a
mutually acceptable valid, legal and enforceable provision that is closest to
the original intention of the parties.

    14.8 Counterparts. This Master Lease and any Schedule may be executed in any
number of counterparts, each of which will be deemed an original, but all such
counterparts together constitute one and the same instrument. If Lessor grants a
security Interest in all or any part of a Schedule, the Equipment or sums
payable thereunder, only that counterpart Schedule marked "Secured Party's
Original" can transfer Lessor's rights and all other counterparts will be marked
"Duplicate".

    14.9 Licensed Products. Lessee shall obtain no Ube to Licensed Products
which will at all times remain the property of the owner of the Licensed
Products. A license from the owner may be required and it Is Lessee's
responsibility to obtain any required license before the use of the Licensed
Products. Lessee agrees to treat the Licensed Products as confidential
Information of the owner, to observe all copyright restrictions, and not to
reproduce or sell the Licensed Products.

    14.10 Additional Documents. Lessee will, upon execution of this Master Lease
and as may be requested thereafter, provide Lessor with a secretary's
certificate of incumbency and authority and any other documents reasonably
requested by Lessor. Upon the execution of each Schedule with an aggregate Rent
in excess of $2,000,000, Lessee will provide Lessor with an opinion from
Lessee's counsel regarding the representations and warranties in Section 8.
Lessee will furnish, upon request, audited financial statements for the most
recent period.

    14.11 Electronic Communications. Each of the parties may communicate with
the other by electronic means under mutually agreeable terms.

    14.12 Definitions.

ASSIGNEE - means an entity to whom Lessor has sold or assigned its rights as
owner and Lessor of Equipment.

ATTACHMENT - means any accessory, equipment or device and the installation
thereof that does not impair the original function or use of the Equipment and
is capable of being removed without causing material damage to the Equipment and
is not an accession to the Equipment.

CASUALTY LOSS - means the irreparable loss or destruction of Equipment.

CASUALTY VALUE - means the amount equal to the present value of the aggregate
Rent remaining for the balance of the current term, plus the present value of
the Fair Market Value (determined as of the expiration of the current term) of
Like Equipment computed using an interest rate equal to the rate for Treasury
Securities having a comparable term to the current term. However, if a Casualty
Value Table is attached to the relevant Schedule its terms will control.

COMMENCEMENT CERTIFICATE - means the Lessor provided certificate which must be
signed by Lessee within ten days of the Commencement Date as requested by
Lessor.

COMMENCEMENT DATE - is defined in each Schedule.

CONTAMINANT - means any material, substance or waste regulated or otherwise
covered under any Environmental Law or other material or substance which has in
the past or could in the future constitute a health, safety or environmental
hazard to any person, property or natural resources.

DEFAULT COSTS - means reasonable attorney's fees and remarketing costs resulting
from a Lessee default or Lessors enforcement of its remedies.

ENVIRONMENTAL LAW - means any federal, foreign, state or local law, rule or
regulation pertaining to the protection of the environment, including, but not
limited to, the Comprehensive Environmental Response, Compensation and Liability
Act ("CERCLA") (42 U.S.C. Section 9601 et seq.), the Federal Water Pollution
Control Act (33 U.S.C. 1251 et seq.), the Resource Conservation and Recovery Act
(42 U.S.C. 6901 et seq.). the Clean Air Act (42 U.S.C. 7401 et seq.), the Toxic
Substances Control Act (15 U.S.C. 2601 et seq.), the Federal Insecticide,
Fungicide and Rodenticide Act (7 U.S.C. 1361 et seq.), and the Occupational
Safety and Health Act (10 U.S.C. 651 et seq.), as these laws have been amended
or supplemented, and any analogous foreign, state or local statutes, and the
regulations promulgated pursuant thereto.

EQUIPMENT - means the property described on a Schedule and any replacement for
that property required or permitted by this Master Lease or a Schedule but not
including any Attachment.


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EVENT OF DEFAULT - means the events described in Subsection 13.1.

FAIR MARKET VALUE - means the aggregate amount which would be obtainable in an
arm's-length transaction between an informed and willing buyer/user purchasing
the Equipment in place for its originally intended use and an informed and
willing seller under no compulsion to sell.

INITIAL TERM - means the period of time beginning on the first day of the first
full Rent Interval following the Commencement Date for all items of Equipment
and continuing for the number of Rent Intervals indicated on a Schedule.

INSTALLATION DATE - means the day on which the Equipment is Installed and
qualified for a commercially available manufacturers standard maintenance
contract or warranty coverage, If available.

INTERIM RENT - means the pro-rata portion of Rent due for the period from the
Commencement Date through but not including the first day of the first full Rent
Interval included In the Initial Term.

LICENSED PRODUCTS - means any software or other licensed products attached to
the Equipment.

LIKE EQUIPMENT - means replacement Equipment which is lien free and of the same
model, type, configuration and manufacture as Equipment.

NOTICE PERIOD - means the time period described in a Schedule during which
Lessee may give Lessor notice of the termination of the term of that Schedule.

OVERDUE RATE - means the lesser of 18% percent or the maximum rate permitted by
the law of the state where the Equipment is located.

OWNER - means the owner of Equipment.

RECONFIGURATION - means any change to Equipment that would upgrade or downgrade
the performance capabilities of the Equipment in any way.

RENT - means the rent, including Interim Rent, Lessee will pay for each item of
Equipment expressed in a Schedule either as a specific amount or an amount equal
to the amount which Lessor pays for an item of Equipment multiplied by a lease
rate factor plus all other amounts due to Lessor under this Master Lease or a
Schedule.

RENT INTERVAL -- means a full calendar month or quarter as indicated on a
Schedule.

SCHEDULE - means an Equipment Schedule which incorporates all of the terms and
conditions of this Master Lease and, for purposes of Section 14.8, its
associated Commencement Certificate(s).

SECURED PARTY - means an entity to whom Lessor has granted a security interest
in a Schedule and related Equipment for the purpose of securing a loan.

VERIFICATION OF DECONTAMINATION - means a letter from the party performing the
decontamination, staling that such party is licensed by the Occupational Safety
and Health Agency or the appropriate officials and that the actual
decontamination was completed both In accordance with manufacturers
specifications and procedures, and any governmental permit required for the
operation of the Equipment and the disposal of any Contaminants.

IN WITNESS WHEREOF, the parties hereto have executed this Master Lease on or as
of the day and year first above written.

NEOTHERAPEUTICS, INC.                  COMDISCO LABORATORY AND SCIENTIFIC GROUP,
as Lessee                              A DIVISION OF COMDISCO, INC.
                                       as Lessor


By:                                    By:
   ------------------------------         ---------------------------------

Title:                                 Title:
     ----------------------------            ------------------------------

rev. 12/99


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