Document:

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                                                                     EXHIBIT 4.7

NEITHER THESE SECURITIES NOR THE SECURITIES INTO WHICH THESE SECURITIES ARE
EXERCISABLE HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR
THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM
REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), AND, ACCORDINGLY, MAY NOT BE OFFERED FOR SALE, SOLD OR OTHERWISE DISPOSED
OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT FILED UNDER THE
SECURITIES ACT OR PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT AND
IN COMPLIANCE WITH APPLICABLE STATE SECURITIES OR BLUE SKY LAWS.

                              NEOTHERAPEUTICS, INC.

                                     WARRANT

                            Dated: September 21, 2000

     NeoTherapeutics, Inc., a Delaware corporation (the "Company"), hereby
certifies that, for value received, Montrose Investments Ltd., a Cayman Islands
corporation or its registered assigns ("Holder"), is entitled, subject to the
terms set forth below, to purchase from the Company up to a total of Forty
Thousand (40,000) shares of Common Stock, $.001 par value per share (the "Common
Stock"), of the Company (each such share, a "Warrant Share" and all such shares,
the "Warrant Shares") at an exercise price equal to $10.47 per share (as
adjusted from time to time as provided in Section 7, the "Exercise Price"), at
any time and from time to time from and after the date hereof and through and
including September 21, 2005 (the "Expiration Date"), and subject to the
following terms and conditions:

     1. Registration of Warrant. The Company shall register this Warrant upon
records to be maintained by the Company for that purpose (the "Warrant
Register"), in the name of the record Holder hereof from time to time. The
Company may deem and treat the registered Holder of this Warrant as the absolute
owner hereof for the purpose of any exercise hereof or any distribution to the
Holder, and for all other purposes, and the Company shall not be affected by
notice to the contrary.

     2. Registration of Transfers and Exchanges.

         (a) This Warrant or the Warrant Shares issued upon any exercise hereof
may only be transferred pursuant to an effective registration statement under
the Securities Act, to the Company or pursuant to an available exemption from or
in a transaction not subject to the registration requirements of the Securities
Act. In connection with any transfer of this Warrant or any Warrant Shares other
than pursuant to an effective registration statement or to the Company, the
Company may require the transferor thereof to provide to the Company an opinion
of counsel selected by the transferor, the form and substance of which opinion
shall be reasonably satisfactory to the Company, to the effect that such
transfer does not require registration of such transferred securities under the
Securities Act. Holder agrees to the imprinting, so long as is required by this
Section 2(a) or Section 3(b) below, of a legend substantially similar to that
first above written on any New Warrant (as defined in Section 2(b) below). Any
such transferee shall agree in writing to be bound by the terms of this Warrant
and shall have the rights of Holder under this Warrant.
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         (b) The Company shall register the transfer of any portion of this
Warrant in conformance with Section 2(a) in the Warrant Register, upon surrender
of this Warrant, with the Form of Assignment attached hereto duly completed and
signed, to the Company at the office specified in or pursuant to Section 10.
Upon any such registration or transfer, a new warrant to purchase Common Stock,
in substantially the form of this Warrant (any such new warrant, a "New
Warrant"), evidencing the portion of this Warrant so transferred shall be issued
to the transferee and a New Warrant evidencing the remaining portion of this
Warrant not so transferred, if any, shall be issued to the transferring Holder.
The acceptance of the New Warrant by the transferee thereof shall be deemed the
acceptance of such transferee of all of the rights and obligations of a holder
of a Warrant.

            (c) This Warrant is exchangeable, upon the surrender hereof by the
Holder to the office of the Company specified in or pursuant to Section 3(b) for
one or more New Warrants, evidencing in the aggregate the right to purchase the
number of Warrant Shares which may then be purchased hereunder.

     3. Duration and Exercise of Warrant.

         (a) This Warrant shall be exercisable by the then registered Holder on
any business day before 5:00 P.M., California time, at any time and from time to
time on or after the date hereof to and including the Expiration Date. At 5:00
P.M., California time on the Expiration Date, the portion of this Warrant not
exercised prior thereto shall be and become void and of no value.

         (b) Subject to Sections 2(c), and 4, upon surrender of this Warrant,
with the Form of Election to Purchase attached hereto duly completed and signed,
to the Company at its address for notice set forth in Section 10 and upon
payment of the Exercise Price multiplied by the number of Warrant Shares that
the Holder intends to purchase hereunder, in the manner provided hereunder, all
as specified by the Holder in the Form of Election to Purchase, the Company
shall promptly, but in no event later than 3 business days after the applicable
Date of Exercise (as defined below), issue or cause to be issued and cause to be
delivered to or upon the written order of the Holder and in such name or names
as the Holder may designate, a certificate for the Warrant Shares issuable upon
such exercise, free of restrictive legends except (i) either in the event that a
registration statement covering the resale of the Warrant Shares and naming the
Holder as a selling stockholder thereunder is not then effective or the Warrant
Shares are not freely transferable without volume restrictions pursuant to Rule
144(k) promulgated under the Securities Act of 1933, as amended (the "Securities
Act"), or (ii) if this Warrant shall have been issued pursuant to a written
agreement between the original Holder and the Company, as required by such
agreement. Any person so designated by the Holder to receive Warrant Shares
shall be deemed to have become holder of record of such Warrant Shares as of the
Date of Exercise of this Warrant.

         A "Date of Exercise" means the date on which the Company shall have
received (i) this Warrant (or any New Warrant, as applicable), with the Form of
Election to Purchase attached hereto (or attached to such New Warrant)
appropriately completed and duly signed, and (ii) payment of the Exercise Price
for the number of Warrant Shares so indicated by the holder hereof to be
purchased.

         (c) This Warrant shall be exercisable, either in its entirety or, from
time to time, for a portion of the number of Warrant Shares. If less than all of
the Warrant Shares which may be purchased under this Warrant are exercised at
any time, the Company shall issue or cause to be issued, at its expense, a New
Warrant evidencing the right to purchase the remaining number of Warrant Shares
for which no exercise has been evidenced by this Warrant.

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         (d) Prior to the exercise of this Warrant, the Holder shall not be
entitled to any rights as a stockholder of the Company with respect to the
Warrant Shares, including (without limitation) the right to vote such shares,
receive dividends or other distributions thereon or be notified of stockholder
meetings (except as otherwise set forth in Section 7(f) herein).

     4. Payment of Taxes. The Company will pay any documentary stamp taxes
attributable to the issuance of Warrant Shares upon the exercise of this
Warrant; provided, however, that the Company shall not be required to pay any
tax which may be payable in respect of any transfer involved in the registration
of any certificates for Warrant Shares or Warrants in a name other than that of
the Holder. The Holder shall be responsible for all other tax liability that may
arise as a result of holding or transferring this Warrant or receiving Warrant
Shares upon exercise hereof.

     5. Replacement of Warrant. If this Warrant is mutilated, lost, stolen or
destroyed, the Company shall issue or cause to be issued in exchange and
substitution for and upon cancellation hereof, or in lieu of and substitution
for this Warrant, a New Warrant, but only upon receipt of evidence reasonably
satisfactory to the Company of such loss, theft or destruction and indemnity, if
requested, satisfactory to it. Applicants for a New Warrant under such
circumstances shall also comply with such other reasonable regulations and
procedures and pay such other reasonable charges as the Company may prescribe.

     6. Reservation of Warrant Shares. The Company covenants that it will at all
times reserve and keep available out of the aggregate of its authorized but
unissued Common Stock, solely for the purpose of enabling it to issue Warrant
Shares upon exercise of this Warrant as herein provided, the number of Warrant
Shares which are then issuable and deliverable upon the exercise of this entire
Warrant, free from preemptive rights or any other actual contingent purchase
rights of persons other than the Holder (taking into account the adjustments and
restrictions of Section 7). The Company covenants that all Warrant Shares that
shall be so issuable and deliverable shall, upon issuance and the payment of the
applicable Exercise Price in accordance with the terms hereof, be duly and
validly authorized, issued and fully paid and nonassessable.

     7. Certain Adjustments. The Exercise Price and number of Warrant Shares
issuable upon exercise of this Warrant are subject to adjustment from time to
time as set forth in this Section 7.

         (a) If the Company, at any time while this Warrant is outstanding, (i)
shall pay a stock dividend (except scheduled dividends paid on outstanding
preferred stock as of the date hereof which contain a stated dividend rate) or
otherwise make a distribution or distributions on shares of its Common Stock or
on any other class of capital stock and not the Common Stock) payable in shares
of Common Stock, (ii) subdivide outstanding shares of Common Stock into a larger
number of shares, or (iii) combine outstanding shares of Common Stock into a
smaller number of shares, the Exercise Price shall be adjusted by multiplying
the Exercise Price in effect immediately before such event by a fraction of
which the numerator shall be the number of shares of Common Stock (excluding
treasury shares, if any) outstanding before such event and the denominator shall
be the number of shares of Common Stock (excluding treasury shares, if any)
outstanding after such event. The number of Warrant shares issuable upon
exercise of this Warrant shall be adjusted upon such adjustment of the Exercise
Price by multiplying the number of Warrant Shares issuable upon exercise of this
Warrant immediately prior to such adjustment by a fraction of which the
denominator shall be the number of shares of Common Stock (excluding treasury
shares, if any) outstanding before such event and the numerator shall be the
number of shares of Common Stock (excluding treasury shares, if any) outstanding
after such event. Any adjustment made pursuant to this Section shall become
effective immediately after the record date for the determination of

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stockholders entitled to receive such dividend or distribution and shall become
effective immediately after the effective date in the case of a subdivision or
combination, and shall apply to successive subdivisions and combinations.

         (b) In case of any reclassification of the Common Stock or any
compulsory share exchange pursuant to which the Common Stock is converted into
other securities, cash or property, then the Holder shall have the right
thereafter to exercise this Warrant only into the shares of stock and other
securities and property receivable upon or deemed to be held by holders of
Common Stock following such reclassification or share exchange, and the Holder
shall be entitled upon such exercise to receive such amount of securities or
property equal to the amount of Warrant Shares such Holder would have been
entitled to had such Holder exercised this Warrant immediately prior to such
reclassification or share exchange. The terms of any such reclassification or
share exchange shall include such terms so as to continue to give to the Holder
the right to receive the securities or property set forth in this Section 7(b)
upon any exercise following any such reclassification or share exchange.

         (c) If the Company, at any time while this Warrant is outstanding,
shall distribute to all holders of Common Stock (and not to holders of this
Warrant) evidences of its indebtedness or assets or rights or warrants to
subscribe for or purchase any security (excluding those referred to in Sections
7(a), (b) and (d)) and other than with respect to rights granted pursuant to a
stockholders rights plan adopted by the Company, then in each such case the
Exercise Price shall be determined by multiplying the Exercise Price in effect
immediately prior to the record date fixed for determination of stockholders
entitled to receive such distribution by a fraction of which the denominator
shall be the Exercise Price determined as of the record date mentioned above,
and of which the numerator shall be such Exercise Price on such record date less
the then fair market value at such record date of the portion of such assets or
evidence of indebtedness so distributed applicable to one outstanding share of
Common Stock as determined by the Company's independent certified public
accountants that regularly examines the financial statements of the Company (the
"Appraiser").

         (d) In case of the closing of any (1) merger or consolidation of the
Company with or into another Person, or (2) sale by the Company of more than
one-half of the assets of the Company (on a book value basis) in one or a series
of related transactions, or (3) tender or other offer or exchange (whether by
the Company or another Person) pursuant to which holders of Common Stock are
permitted to tender or exchange their shares for other securities, stock, cash
or property of the Company or another Person; then the Holder shall have the
right thereafter to (A) exercise this Warrant for the shares of stock and other
securities, cash and property receivable upon or deemed to be held by holders of
Common Stock following such merger, consolidation or sale, and the Holder shall
be entitled upon exercise of this Warrant to receive such amount of securities,
cash and property as the Common Stock for which this Warrant could have been
exercised immediately prior to such merger, consolidation or sales would have
been entitled, or (B) in the event of an exchange or tender offer or other
transaction contemplated by clause (3) of this Section, tender or exchange this
Warrant for such securities, stock, cash and other property receivable upon or
deemed to be held by holders of Common Stock that have tendered or exchanged
their shares of Common Stock following such tender or exchange, and the Holder
shall be entitled upon such exchange or tender to receive such amount of
securities, cash and property as the shares of Common Stock for which this
Warrant could have been exercised immediately prior to such tender or exchange
would have been entitled as would have been issued. The terms of any such
merger, sale, consolidation, tender or exchange shall include such terms so as
continue to give the Holder the right to receive the securities, cash and
property set forth in this Section upon any conversion or redemption following
such event. This provision shall similarly apply to successive such events.

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         (e) For the purposes of this Section 7, the number of shares of Common
Stock outstanding at any time shall be deemed to include the aggregate maximum
number of shares of Common Stock deliverable upon exercise, conversion or
exchange, as applicable (assuming the satisfaction of any conditions to
exercisability, convertibility or exchangeability, as applicable, including,
without limitation, the passage of time), of any options to purchase or rights
to subscribe for Common Stock, securities by their terms convertible into or
exchangeable for Common Stock or options to purchase or rights to subscribe for
such convertible or exchangeable securities then outstanding.

         (f) All calculations under this Section 7 shall be made to the nearest
cent or the nearest 1/100th of a share, as the case may be.

         (g) If:

               (i)  the Company shall declare a dividend (or any other
                    distribution) on its Common Stock; or

               (ii) the Company shall declare a special nonrecurring cash
                    dividend on or a redemption of its Common Stock; or

              (iii) the Company shall authorize the granting to all holders of
                    the Common Stock rights or warrants to subscribe for or
                    purchase any shares of capital stock of any class or of any
                    rights; or

               (iv) the approval of any stockholders of the Company shall be
                    required in connection with any reclassification of the
                    Common Stock, any consolidation or merger to which the
                    Company is a party, any sale or transfer of all or
                    substantially all of the assets of the Company, or any
                    compulsory share exchange whereby the Common Stock is
                    converted into other securities, cash or property; or

               (v)  the Company shall authorize the voluntary dissolution,
                    liquidation or winding up of the affairs of the Company,

then the Company shall cause to be mailed to each Holder at their last addresses
as they shall appear upon the Warrant Register, at least 15 calendar days prior
to the applicable record or effective date hereinafter specified, a notice
stating (x) the date on which a record is to be taken for the purpose of such
dividend, distribution, redemption, rights or warrants, or if a record is not to
be taken, the date as of which the holders of Common Stock of record to be
entitled to such dividend, distributions, redemption, rights or warrants are to
be determined or (y) the date on which such reclassification, consolidation,
merger, sale, transfer or share exchange is expected to become effective or
close, and the date as of which it is expected that holders of Common Stock of
record shall be entitled to exchange their shares of Common Stock for
securities, cash or other property deliverable upon such reclassification,
consolidation, merger, sale, transfer, share exchange, dissolution, liquidation
or winding up; provided, however, that the failure to mail such notice or any
defect therein or in the mailing thereof shall not affect the validity of the
corporate action required to be specified in such notice.

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     8. Payment of Exercise Price. The Holder shall pay the Exercise Price in
one of the following manners:

         (a) Cash Exercise. The Holder may deliver immediately available funds
by certified check or bank draft payable to the order of the Company or by wire
transfer to an account designated by the Company; or

         (b) Cashless Exercise. The Holder may surrender this Warrant to the
Company together with a notice of cashless exercise, in which event the Company
shall issue to the Holder the number of Warrant Shares determined as follows:

                  X =   Y (A-B)
                        -------
                           A
      where:

      X = the number of Warrant Shares to be issued to the Holder.

      Y = the number of Warrant Shares with respect to which this Warrant is
being exercised.

      A = the average of the closing sale prices of the Common Stock for the
five (5) trading days immediately prior to (but not including) the Date of
Exercise.

      B = the Exercise Price.

     For purposes of Rule 144 promulgated under the Securities Act, it is
intended, understood and acknowledged that the Warrant Shares issued in a
cashless exercise transaction shall be deemed to have been acquired by the
Holder, and the holding period for the Warrant Shares shall be deemed to have
been commenced, on the issue date.

     9. Fractional Shares. The Company shall not be required to issue or cause
to be issued fractional Warrant Shares on the exercise of this Warrant. The
number of full Warrant Shares which shall be issuable upon the exercise of this
Warrant shall be computed on the basis of the aggregate number of Warrant Shares
purchasable on exercise of this Warrant so presented. If any fraction of a
Warrant Share would, except for the provisions of this Section 9, be issuable on
the exercise of this Warrant, the Company shall pay an amount in cash equal to
the Exercise Price multiplied by such fraction.

     10. Certain Exercise Restrictions.

         (a) A Holder may not exercise this Warrant to the extent such exercise
would result in the Holder, together with any affiliate thereof, beneficially
owning (as determined in accordance with Section 13(d) of the Securities
Exchange Act of 1934, as amended and the rules promulgated thereunder) in excess
of 4.999% of the then issued and outstanding shares of Common Stock, including
shares of Common Stock issuable upon such exercise and held by such Holder after
application of this Section. Since the Holder will not be obligated to report to
the Company the number of shares of Common Stock it may hold at the time of an
exercise hereunder, unless the exercise at issue would result in the issuance of
shares of Common Stock in excess of 4.999% of the then outstanding shares of
Common Stock without regard to any other shares which may be beneficially owned
by the Holder or an affiliate thereof, the Holder shall have the authority and
obligation to determine whether the restriction contained in this Section will
limit any particular exercise hereunder and to the extent that the Holder
determines that the limitation contained in this

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Section applies, the determination of which portion of this Warrant is
exercisable shall be the responsibility and obligation of the Holder. If the
Holder has delivered a Form of Election to Purchase for a number of Warrant
Shares that, without regard to any other shares that the Holder or its
affiliates may beneficially own, would result in the issuance in excess of the
permitted amount hereunder, the Company shall notify the Holder of this fact and
shall honor the exercise for the maximum portion of this Warrant permitted to be
exercised on such Date of Exercise in accordance with the periods described
herein and, at the option of the Holder, either keep the portion of the Warrant
tendered for exercise in excess of the permitted amount hereunder for future
exercises or return such excess portion of the Warrant to the Holder. The
provisions of this Section may be waived by a Holder (but only as to itself and
not to any other Holder) upon not less than 61 days prior notice to the Company.
Other Holders shall be unaffected by any such waiver.

         (b) A Holder may not exercise this Warrant to the extent such exercise
would result in the Holder, together with any affiliate thereof, beneficially
owning (as determined in accordance with Section 13(d) of the Securities
Exchange Act of 1934, as amended and the rules promulgated thereunder) in excess
of 9.999% of the then issued and outstanding shares of Common Stock, including
shares of Common Stock issuable upon such exercise and held by such Holder after
application of this Section. Since the Holder will not be obligated to report to
the Company the number of shares of Common Stock it may hold at the time of an
exercise hereunder, unless the exercise at issue would result in the issuance of
shares of Common Stock in excess of 9.999% of the then outstanding shares of
Common Stock without regard to any other shares which may be beneficially owned
by the Holder or an affiliate thereof, the Holder shall have the authority and
obligation to determine whether the restriction contained in this Section will
limit any particular exercise hereunder and to the extent that the Holder
determines that the limitation contained in this Section applies, the
determination of which portion of this Warrant is exercisable shall be the
responsibility and obligation of the Holder. If the Holder has delivered a Form
of Election to Purchase for a number of Warrant Shares that, without regard to
any other shares that the Holder or its affiliates may beneficially own, would
result in the issuance in excess of the permitted amount hereunder, the Company
shall notify the Holder of this fact and shall honor the exercise for the
maximum portion of this Warrant permitted to be exercised on such Date of
Exercise in accordance with the periods described herein and, at the option of
the Holder, either keep the portion of the Warrant tendered for exercise in
excess of the permitted amount hereunder for future exercises or return such
excess portion of the Warrant to the Holder. The provisions of this Section may
be waived by a Holder (but only as to itself and not to any other Holder) upon
not less than 61 days prior notice to the Company. Other Holders shall be
unaffected by any such waiver.

     11. Notices. Any and all notices or other communications or deliveries
hereunder shall be in writing and shall be deemed given and effective on the
earliest of (i) the date of transmission, if such notice or communication is
delivered via facsimile at the facsimile telephone number specified in this
Section prior to 5:00 p.m. (California time) on a business day, (ii) the
business day after the date of transmission, if such notice or communication is
delivered via facsimile at the facsimile telephone number specified in this
Section later than 5:00 p.m. (California time) on any date and earlier than
11:59 p.m. (California time) on such date, (iii) the business day following the
date of mailing, if sent by nationally recognized overnight courier service, or
(iv) upon actual receipt by the party to whom such notice is required to be
given. The addresses for such communications shall be: (i) if to the Company, to
157 Technology Drive, Irvine, CA 92618, Attention: Chief Financial Officer, or
to facsimile no. (949) 788-6706, with a copy to Latham & Watkins, 650 Town
Center Drive, Suite 2000, Costa Mesa, California 92626, attention Alan W.
Pettis, Esq., or (ii) if to the Holder, to the Holder at the address or
facsimile number appearing on the Warrant Register or such other address or
facsimile number as the Holder may provide to the Company in accordance with

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this Section 10, with a copy to Robinson Silverman Pearce Aronsohn & Berman LLP,
1290 Avenue of the Americas, New York, New York 10104, attention Eric L. Cohen,
Esq.

     12. Warrant Agent. The Company shall serve as warrant agent under this
Warrant. The Company may appoint a new warrant agent upon notice to the Holder
in accordance with Section 10. Any corporation into which the Company may be
merged or any corporation resulting from any consolidation to which the Company
shall be a party or any corporation to which the Company transfers substantially
all of its corporate assets shall be a successor warrant agent under this
Warrant without any further act. Any such successor warrant agent shall promptly
cause notice of its succession as warrant agent to be mailed (by first class
mail, postage prepaid) to the Holder at the Holder's last address as shown on
the Warrant Register.

     13. Miscellaneous.

         (a) This Warrant shall be binding on and inure to the benefit of the
parties hereto and their respective successors and permitted assigns. This
Warrant may be amended only in writing signed by the Company and the Holder and
their successors and assigns.

         (b) Subject to Section 12(a), above, nothing in this Warrant shall be
construed to give to any person or corporation other than the Company and the
Holder any legal or equitable right, remedy or cause under this Warrant. This
Warrant shall inure to the sole and exclusive benefit of the Company and the
Holder.

         (c) The corporate laws of the State of Delaware shall govern all issues
concerning the relative rights of the Company and its stockholders. All other
questions concerning the construction, validity, enforcement and interpretation
of this Warrant shall be governed by and construed and enforced in accordance
with the internal laws of the State of New York, without regard to the
principles of conflicts of law thereof. The Company and the Holder hereby
irrevocably submit to the exclusive jurisdiction of the state and federal courts
sitting in the City of New York, borough of Manhattan, for the adjudication of
any dispute hereunder or in connection herewith or with any transaction
contemplated hereby or discussed herein, and hereby irrevocably waive, and agree
not to assert in any suit, action or proceeding, any claim that it is not
personally subject to the jurisdiction of any such court, or that such suit,
action or proceeding is improper. Each of the Company and the Holder hereby
irrevocably waives personal service of process and consents to process being
served in any such suit, action or proceeding by receiving a copy thereof sent
to the Company at the address in effect for notices to it under this instrument
and agrees that such service shall constitute good and sufficient service of
process and notice thereof. Nothing

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contained herein shall be deemed to limit in any way any right to serve process
in any manner permitted by law.

         (d) The headings herein are for convenience only, do not constitute a
part of this Warrant and shall not be deemed to limit or affect any of the
provisions hereof.

         (e) In case any one or more of the provisions of this Warrant shall be
invalid or unenforceable in any respect, the validity and enforceability of the
remaining terms and provisions of this Warrant shall not in any way be affected
or impaired thereby and the parties will attempt in good faith to agree upon a
valid and enforceable provision which shall be a commercially reasonable
substitute therefor, and upon so agreeing, shall incorporate such substitute
provision in this Warrant.

     IN WITNESS WHEREOF, the Company has caused this Warrant to be duly executed
by its authorized officer as of the date first indicated above.

                                    NEOTHERAPEUTICS, INC.

                                    By: /s/ Samuel Gulko
                                        --------------------------------------
                                        Samuel Gulko
                                        Chief Financial Officer

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                         FORM OF ELECTION TO PURCHASE

(To be executed by the Holder to exercise the right to purchase shares of Common
Stock under the foregoing Warrant)

To NeoTherapeutics, Inc.:

      In accordance with the Warrant enclosed with this Form of Election to
Purchase, the undersigned hereby irrevocably elects to purchase __________
shares of common stock ("Common Stock"), $.001 par value per share, of
NeoTherapeutics, Inc. and if such Holder is not utilizing the Cashless Exercise
provisions set forth in the Warrant, encloses herewith $__________ in cash,
certified or official bank check or checks, which sum represents the aggregate
Exercise Price (as defined in the Warrant) for the number of shares of Common
Stock to which this Form of Election to Purchase relates, together with any
applicable taxes payable by the undersigned pursuant to the Warrant.

      The undersigned requests that certificates for the shares of Common Stock
issuable upon this exercise be issued in the name of

                                    PLEASE INSERT SOCIAL SECURITY OR
                                    TAX IDENTIFICATION NUMBER

                                    --------------------------------------------

--------------------------------------------------------------------------------
                       (Please print name and address)

     If the number of shares of Common Stock issuable upon this exercise shall
not be all of the shares of Common Stock which the undersigned is entitled to
purchase in accordance with the enclosed Warrant, the undersigned requests that
a New Warrant (as defined in the Warrant) evidencing the right to purchase the
shares of Common Stock not issuable pursuant to the exercise evidenced hereby be
issued in the name of and delivered to:

--------------------------------------------------------------------------------
                         (Please print name and address)

--------------------------------------------------------------------------------

Dated:  __________, ____            Name of Holder:

                                    (Print)
                                             ---------------------------------

                                    (By:)
                                           -----------------------------------

                                    (Name:)
                                    (Title:)
                                    (Signature must conform in all respects
                                    to name of holder as specified on the
                                    face of the Warrant)
<PAGE>   11
                               FORM OF ASSIGNMENT

           [To be completed and signed only upon transfer of Warrant]

     FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers
unto ____________________ the right represented by the Warrant enclosed with
this Form of Assignment to purchase __________ shares of Common Stock of
NeoTherapeutics, Inc. to which the Warrant relates and appoints
____________________ attorney to transfer said right on the books of
NeoTherapeutics, Inc. with full power of substitution in the premises.

Dated:  __________, ____

                                    ---------------------------------------
                                    (Signature must conform in all respects
                                    to name of holder as specified on the
                                    face of the Warrant)

                                    ---------------------------------------
                                    Address of Transferee

                                    ---------------------------------------

                                    ---------------------------------------

In the presence of:

--------------------------<PAGE>   1
                                                                     EXHIBIT 4.8

NEITHER THESE SECURITIES NOR THE SECURITIES INTO WHICH THESE SECURITIES ARE
EXERCISABLE HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR
THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM
REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), AND, ACCORDINGLY, MAY NOT BE OFFERED FOR SALE, SOLD OR OTHERWISE DISPOSED
OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT FILED UNDER THE
SECURITIES ACT OR PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT AND
IN COMPLIANCE WITH APPLICABLE STATE SECURITIES OR BLUE SKY LAWS.

                              NEOTHERAPEUTICS, INC.

                                     WARRANT

                            Dated: September 21, 2000

     NeoTherapeutics, Inc., a Delaware corporation (the "Company"), hereby
certifies that, for value received, Strong River Investments, Inc., a Cayman
Islands corporation or its registered assigns ("Holder"), is entitled, subject
to the terms set forth below, to purchase from the Company up to a total of
Forty Thousand (40,000) shares of Common Stock, $.001 par value per share (the
"Common Stock"), of the Company (each such share, a "Warrant Share" and all such
shares, the "Warrant Shares") at an exercise price equal to $10.47 per share (as
adjusted from time to time as provided in Section 7, the "Exercise Price"), at
any time and from time to time from and after the date hereof and through and
including September 21, 2005 (the "Expiration Date"), and subject to the
following terms and conditions:

     1. Registration of Warrant. The Company shall register this Warrant upon
records to be maintained by the Company for that purpose (the "Warrant
Register"), in the name of the record Holder hereof from time to time. The
Company may deem and treat the registered Holder of this Warrant as the absolute
owner hereof for the purpose of any exercise hereof or any distribution to the
Holder, and for all other purposes, and the Company shall not be affected by
notice to the contrary.

     2. Registration of Transfers and Exchanges.

         (a) This Warrant or the Warrant Shares issued upon any exercise hereof
may only be transferred pursuant to an effective registration statement under
the Securities Act, to the Company or pursuant to an available exemption from or
in a transaction not subject to the registration requirements of the Securities
Act. In connection with any transfer of this Warrant or any Warrant Shares other
than pursuant to an effective registration statement or to the Company, the
Company may require the transferor thereof to provide to the Company an opinion
of counsel selected by the transferor, the form and substance of which opinion
shall be reasonably satisfactory to the Company, to the effect that such
transfer does not require registration of such transferred securities under the
Securities Act. Holder agrees to the imprinting, so long as is required by this
Section 2(a) or Section 3(b) below, of a legend substantially similar to that
first above written on any New Warrant (as defined in Section 2(b) below). Any
such transferee shall agree in writing to be bound by the terms of this Warrant
and shall have the rights of Holder under this Warrant.
<PAGE>   2
         (b) The Company shall register the transfer of any portion of this
Warrant in conformance with Section 2(a) in the Warrant Register, upon surrender
of this Warrant, with the Form of Assignment attached hereto duly completed and
signed, to the Company at the office specified in or pursuant to Section 10.
Upon any such registration or transfer, a new warrant to purchase Common Stock,
in substantially the form of this Warrant (any such new warrant, a "New
Warrant"), evidencing the portion of this Warrant so transferred shall be issued
to the transferee and a New Warrant evidencing the remaining portion of this
Warrant not so transferred, if any, shall be issued to the transferring Holder.
The acceptance of the New Warrant by the transferee thereof shall be deemed the
acceptance of such transferee of all of the rights and obligations of a holder
of a Warrant.

         (c) This Warrant is exchangeable, upon the surrender hereof by the
Holder to the office of the Company specified in or pursuant to Section 3(b) for
one or more New Warrants, evidencing in the aggregate the right to purchase the
number of Warrant Shares which may then be purchased hereunder.

     3. Duration and Exercise of Warrant.

         (a) This Warrant shall be exercisable by the then registered Holder on
any business day before 5:00 P.M., California time, at any time and from time to
time on or after the date hereof to and including the Expiration Date. At 5:00
P.M., California time on the Expiration Date, the portion of this Warrant not
exercised prior thereto shall be and become void and of no value.

         (b) Subject to Sections 2(c), and 4, upon surrender of this Warrant,
with the Form of Election to Purchase attached hereto duly completed and signed,
to the Company at its address for notice set forth in Section 10 and upon
payment of the Exercise Price multiplied by the number of Warrant Shares that
the Holder intends to purchase hereunder, in the manner provided hereunder, all
as specified by the Holder in the Form of Election to Purchase, the Company
shall promptly, but in no event later than 3 business days after the applicable
Date of Exercise (as defined below), issue or cause to be issued and cause to be
delivered to or upon the written order of the Holder and in such name or names
as the Holder may designate, a certificate for the Warrant Shares issuable upon
such exercise, free of restrictive legends except (i) either in the event that a
registration statement covering the resale of the Warrant Shares and naming the
Holder as a selling stockholder thereunder is not then effective or the Warrant
Shares are not freely transferable without volume restrictions pursuant to Rule
144(k) promulgated under the Securities Act of 1933, as amended (the "Securities
Act"), or (ii) if this Warrant shall have been issued pursuant to a written
agreement between the original Holder and the Company, as required by such
agreement. Any person so designated by the Holder to receive Warrant Shares
shall be deemed to have become holder of record of such Warrant Shares as of the
Date of Exercise of this Warrant.

         A "Date of Exercise" means the date on which the Company shall have
received (i) this Warrant (or any New Warrant, as applicable), with the Form of
Election to Purchase attached hereto (or attached to such New Warrant)
appropriately completed and duly signed, and (ii) payment of the Exercise Price
for the number of Warrant Shares so indicated by the holder hereof to be
purchased.

         (c) This Warrant shall be exercisable, either in its entirety or, from
time to time, for a portion of the number of Warrant Shares. If less than all of
the Warrant Shares which may be purchased under this Warrant are exercised at
any time, the Company shall issue or cause to be issued, at its expense, a New
Warrant evidencing the right to purchase the remaining number of Warrant Shares
for which no exercise has been evidenced by this Warrant.

                                       2
<PAGE>   3
         (d) Prior to the exercise of this Warrant, the Holder shall not be
entitled to any rights as a stockholder of the Company with respect to the
Warrant Shares, including (without limitation) the right to vote such shares,
receive dividends or other distributions thereon or be notified of stockholder
meetings (except as otherwise set forth in Section 7(f) herein).

     4. Payment of Taxes. The Company will pay any documentary stamp taxes
attributable to the issuance of Warrant Shares upon the exercise of this
Warrant; provided, however, that the Company shall not be required to pay any
tax which may be payable in respect of any transfer involved in the registration
of any certificates for Warrant Shares or Warrants in a name other than that of
the Holder. The Holder shall be responsible for all other tax liability that may
arise as a result of holding or transferring this Warrant or receiving Warrant
Shares upon exercise hereof.

     5. Replacement of Warrant. If this Warrant is mutilated, lost, stolen or
destroyed, the Company shall issue or cause to be issued in exchange and
substitution for and upon cancellation hereof, or in lieu of and substitution
for this Warrant, a New Warrant, but only upon receipt of evidence reasonably
satisfactory to the Company of such loss, theft or destruction and indemnity, if
requested, satisfactory to it. Applicants for a New Warrant under such
circumstances shall also comply with such other reasonable regulations and
procedures and pay such other reasonable charges as the Company may prescribe.

     6. Reservation of Warrant Shares. The Company covenants that it will at all
times reserve and keep available out of the aggregate of its authorized but
unissued Common Stock, solely for the purpose of enabling it to issue Warrant
Shares upon exercise of this Warrant as herein provided, the number of Warrant
Shares which are then issuable and deliverable upon the exercise of this entire
Warrant, free from preemptive rights or any other actual contingent purchase
rights of persons other than the Holder (taking into account the adjustments and
restrictions of Section 7). The Company covenants that all Warrant Shares that
shall be so issuable and deliverable shall, upon issuance and the payment of the
applicable Exercise Price in accordance with the terms hereof, be duly and
validly authorized, issued and fully paid and nonassessable.

     7. Certain Adjustments. The Exercise Price and number of Warrant Shares
issuable upon exercise of this Warrant are subject to adjustment from time to
time as set forth in this Section 7.

         (a) If the Company, at any time while this Warrant is outstanding, (i)
shall pay a stock dividend (except scheduled dividends paid on outstanding
preferred stock as of the date hereof which contain a stated dividend rate) or
otherwise make a distribution or distributions on shares of its Common Stock or
on any other class of capital stock and not the Common Stock) payable in shares
of Common Stock, (ii) subdivide outstanding shares of Common Stock into a larger
number of shares, or (iii) combine outstanding shares of Common Stock into a
smaller number of shares, the Exercise Price shall be adjusted by multiplying
the Exercise Price in effect immediately before such event by a fraction of
which the numerator shall be the number of shares of Common Stock (excluding
treasury shares, if any) outstanding before such event and the denominator shall
be the number of shares of Common Stock (excluding treasury shares, if any)
outstanding after such event. The number of Warrant shares issuable upon
exercise of this Warrant shall be adjusted upon such adjustment of the Exercise
Price by multiplying the number of Warrant Shares issuable upon exercise of this
Warrant immediately prior to such adjustment by a fraction of which the
denominator shall be the number of shares of Common Stock (excluding treasury
shares, if any) outstanding before such event and the numerator shall be the
number of shares of Common Stock (excluding treasury shares, if any) outstanding
after such event. Any adjustment made pursuant to this Section shall become
effective immediately after the record date for the determination of

                                       3
<PAGE>   4
stockholders entitled to receive such dividend or distribution and shall become
effective immediately after the effective date in the case of a subdivision or
combination, and shall apply to successive subdivisions and combinations.

            (b) In case of any reclassification of the Common Stock or any
compulsory share exchange pursuant to which the Common Stock is converted into
other securities, cash or property, then the Holder shall have the right
thereafter to exercise this Warrant only into the shares of stock and other
securities and property receivable upon or deemed to be held by holders of
Common Stock following such reclassification or share exchange, and the Holder
shall be entitled upon such exercise to receive such amount of securities or
property equal to the amount of Warrant Shares such Holder would have been
entitled to had such Holder exercised this Warrant immediately prior to such
reclassification or share exchange. The terms of any such reclassification or
share exchange shall include such terms so as to continue to give to the Holder
the right to receive the securities or property set forth in this Section 7(b)
upon any exercise following any such reclassification or share exchange.

            (c) If the Company, at any time while this Warrant is outstanding,
shall distribute to all holders of Common Stock (and not to holders of this
Warrant) evidences of its indebtedness or assets or rights or warrants to
subscribe for or purchase any security (excluding those referred to in Sections
7(a), (b) and (d)) and other than with respect to rights granted pursuant to a
stockholders rights plan adopted by the Company, then in each such case the
Exercise Price shall be determined by multiplying the Exercise Price in effect
immediately prior to the record date fixed for determination of stockholders
entitled to receive such distribution by a fraction of which the denominator
shall be the Exercise Price determined as of the record date mentioned above,
and of which the numerator shall be such Exercise Price on such record date less
the then fair market value at such record date of the portion of such assets or
evidence of indebtedness so distributed applicable to one outstanding share of
Common Stock as determined by the Company's independent certified public
accountants that regularly examines the financial statements of the Company (the
"Appraiser").

            (d) In case of the closing of any (1) merger or consolidation of the
Company with or into another Person, or (2) sale by the Company of more than
one-half of the assets of the Company (on a book value basis) in one or a series
of related transactions, or (3) tender or other offer or exchange (whether by
the Company or another Person) pursuant to which holders of Common Stock are
permitted to tender or exchange their shares for other securities, stock, cash
or property of the Company or another Person; then the Holder shall have the
right thereafter to (A) exercise this Warrant for the shares of stock and other
securities, cash and property receivable upon or deemed to be held by holders of
Common Stock following such merger, consolidation or sale, and the Holder shall
be entitled upon exercise of this Warrant to receive such amount of securities,
cash and property as the Common Stock for which this Warrant could have been
exercised immediately prior to such merger, consolidation or sales would have
been entitled, or (B) in the event of an exchange or tender offer or other
transaction contemplated by clause (3) of this Section, tender or exchange this
Warrant for such securities, stock, cash and other property receivable upon or
deemed to be held by holders of Common Stock that have tendered or exchanged
their shares of Common Stock following such tender or exchange, and the Holder
shall be entitled upon such exchange or tender to receive such amount of
securities, cash and property as the shares of Common Stock for which this
Warrant could have been exercised immediately prior to such tender or exchange
would have been entitled as would have been issued. The terms of any such
merger, sale, consolidation, tender or exchange shall include such terms so as
continue to give the Holder the right to receive the securities, cash and
property set forth in this Section upon any conversion or redemption following
such event. This provision shall similarly apply to successive such events.

                                       4
<PAGE>   5
         (e) For the purposes of this Section 7, the number of shares of Common
Stock outstanding at any time shall be deemed to include the aggregate maximum
number of shares of Common Stock deliverable upon exercise, conversion or
exchange, as applicable (assuming the satisfaction of any conditions to
exercisability, convertibility or exchangeability, as applicable, including,
without limitation, the passage of time), of any options to purchase or rights
to subscribe for Common Stock, securities by their terms convertible into or
exchangeable for Common Stock or options to purchase or rights to subscribe for
such convertible or exchangeable securities then outstanding.

         (f) All calculations under this Section 7 shall be made to the nearest
cent or the nearest 1/100th of a share, as the case may be.

         (g) If:

               (i)  the Company shall declare a dividend (or any other
                    distribution) on its Common Stock; or

               (ii) the Company shall declare a special nonrecurring cash
                    dividend on or a redemption of its Common Stock; or

              (iii) the Company shall authorize the granting to all holders of
                    the Common Stock rights or warrants to subscribe for or
                    purchase any shares of capital stock of any class or of any
                    rights; or

               (iv) the approval of any stockholders of the Company shall be
                    required in connection with any reclassification of the
                    Common Stock, any consolidation or merger to which the
                    Company is a party, any sale or transfer of all or
                    substantially all of the assets of the Company, or any
                    compulsory share exchange whereby the Common Stock is
                    converted into other securities, cash or property; or

               (v)  the Company shall authorize the voluntary dissolution,
                    liquidation or winding up of the affairs of the Company,

then the Company shall cause to be mailed to each Holder at their last addresses
as they shall appear upon the Warrant Register, at least 15 calendar days prior
to the applicable record or effective date hereinafter specified, a notice
stating (x) the date on which a record is to be taken for the purpose of such
dividend, distribution, redemption, rights or warrants, or if a record is not to
be taken, the date as of which the holders of Common Stock of record to be
entitled to such dividend, distributions, redemption, rights or warrants are to
be determined or (y) the date on which such reclassification, consolidation,
merger, sale, transfer or share exchange is expected to become effective or
close, and the date as of which it is expected that holders of Common Stock of
record shall be entitled to exchange their shares of Common Stock for
securities, cash or other property deliverable upon such reclassification,
consolidation, merger, sale, transfer, share exchange, dissolution, liquidation
or winding up; provided, however, that the failure to mail such notice or any
defect therein or in the mailing thereof shall not affect the validity of the
corporate action required to be specified in such notice.

                                       5
<PAGE>   6
     8. Payment of Exercise Price. The Holder shall pay the Exercise Price in
one of the following manners:

         (a) Cash Exercise. The Holder may deliver immediately available funds
by certified check or bank draft payable to the order of the Company or by wire
transfer to an account designated by the Company; or

         (b) Cashless Exercise. The Holder may surrender this Warrant to the
Company together with a notice of cashless exercise, in which event the Company
shall issue to the Holder the number of Warrant Shares determined as follows:

                  X =   Y (A-B)
                        -------
                           A
      where:

      X = the number of Warrant Shares to be issued to the Holder.

      Y = the number of Warrant Shares with respect to which this Warrant is
being exercised.

      A = the average of the closing sale prices of the Common Stock for the
five (5) trading days immediately prior to (but not including) the Date of
Exercise.

      B = the Exercise Price.

     For purposes of Rule 144 promulgated under the Securities Act, it is
intended, understood and acknowledged that the Warrant Shares issued in a
cashless exercise transaction shall be deemed to have been acquired by the
Holder, and the holding period for the Warrant Shares shall be deemed to have
been commenced, on the issue date.

     9. Fractional Shares. The Company shall not be required to issue or cause
to be issued fractional Warrant Shares on the exercise of this Warrant. The
number of full Warrant Shares which shall be issuable upon the exercise of this
Warrant shall be computed on the basis of the aggregate number of Warrant Shares
purchasable on exercise of this Warrant so presented. If any fraction of a
Warrant Share would, except for the provisions of this Section 9, be issuable on
the exercise of this Warrant, the Company shall pay an amount in cash equal to
the Exercise Price multiplied by such fraction.

     10. Certain Exercise Restrictions.

         (a) A Holder may not exercise this Warrant to the extent such exercise
would result in the Holder, together with any affiliate thereof, beneficially
owning (as determined in accordance with Section 13(d) of the Securities
Exchange Act of 1934, as amended and the rules promulgated thereunder) in excess
of 4.999% of the then issued and outstanding shares of Common Stock, including
shares of Common Stock issuable upon such exercise and held by such Holder after
application of this Section. Since the Holder will not be obligated to report to
the Company the number of shares of Common Stock it may hold at the time of an
exercise hereunder, unless the exercise at issue would result in the issuance of
shares of Common Stock in excess of 4.999% of the then outstanding shares of
Common Stock without regard to any other shares which may be beneficially owned
by the Holder or an affiliate thereof, the Holder shall have the authority and
obligation to determine whether the restriction contained in this Section will
limit any particular exercise hereunder and to the extent that the Holder
determines that the limitation contained in this

                                       6
<PAGE>   7
Section applies, the determination of which portion of this Warrant is
exercisable shall be the responsibility and obligation of the Holder. If the
Holder has delivered a Form of Election to Purchase for a number of Warrant
Shares that, without regard to any other shares that the Holder or its
affiliates may beneficially own, would result in the issuance in excess of the
permitted amount hereunder, the Company shall notify the Holder of this fact and
shall honor the exercise for the maximum portion of this Warrant permitted to be
exercised on such Date of Exercise in accordance with the periods described
herein and, at the option of the Holder, either keep the portion of the Warrant
tendered for exercise in excess of the permitted amount hereunder for future
exercises or return such excess portion of the Warrant to the Holder. The
provisions of this Section may be waived by a Holder (but only as to itself and
not to any other Holder) upon not less than 61 days prior notice to the Company.
Other Holders shall be unaffected by any such waiver.

         (b) A Holder may not exercise this Warrant to the extent such exercise
would result in the Holder, together with any affiliate thereof, beneficially
owning (as determined in accordance with Section 13(d) of the Securities
Exchange Act of 1934, as amended and the rules promulgated thereunder) in excess
of 9.999% of the then issued and outstanding shares of Common Stock, including
shares of Common Stock issuable upon such exercise and held by such Holder after
application of this Section. Since the Holder will not be obligated to report to
the Company the number of shares of Common Stock it may hold at the time of an
exercise hereunder, unless the exercise at issue would result in the issuance of
shares of Common Stock in excess of 9.999% of the then outstanding shares of
Common Stock without regard to any other shares which may be beneficially owned
by the Holder or an affiliate thereof, the Holder shall have the authority and
obligation to determine whether the restriction contained in this Section will
limit any particular exercise hereunder and to the extent that the Holder
determines that the limitation contained in this Section applies, the
determination of which portion of this Warrant is exercisable shall be the
responsibility and obligation of the Holder. If the Holder has delivered a Form
of Election to Purchase for a number of Warrant Shares that, without regard to
any other shares that the Holder or its affiliates may beneficially own, would
result in the issuance in excess of the permitted amount hereunder, the Company
shall notify the Holder of this fact and shall honor the exercise for the
maximum portion of this Warrant permitted to be exercised on such Date of
Exercise in accordance with the periods described herein and, at the option of
the Holder, either keep the portion of the Warrant tendered for exercise in
excess of the permitted amount hereunder for future exercises or return such
excess portion of the Warrant to the Holder. The provisions of this Section may
be waived by a Holder (but only as to itself and not to any other Holder) upon
not less than 61 days prior notice to the Company. Other Holders shall be
unaffected by any such waiver.

     11. Notices. Any and all notices or other communications or deliveries
hereunder shall be in writing and shall be deemed given and effective on the
earliest of (i) the date of transmission, if such notice or communication is
delivered via facsimile at the facsimile telephone number specified in this
Section prior to 5:00 p.m. (California time) on a business day, (ii) the
business day after the date of transmission, if such notice or communication is
delivered via facsimile at the facsimile telephone number specified in this
Section later than 5:00 p.m. (California time) on any date and earlier than
11:59 p.m. (California time) on such date, (iii) the business day following the
date of mailing, if sent by nationally recognized overnight courier service, or
(iv) upon actual receipt by the party to whom such notice is required to be
given. The addresses for such communications shall be: (i) if to the Company, to
157 Technology Drive, Irvine, CA 92618, Attention: Chief Financial Officer, or
to facsimile no. (949) 788-6706, with a copy to Latham & Watkins, 650 Town
Center Drive, Suite 2000, Costa Mesa, California 92626, attention Alan W.
Pettis, Esq., or (ii) if to the Holder, to the Holder at the address or
facsimile number appearing on the Warrant Register or such other address or
facsimile number as the Holder may provide to the Company in accordance with

                                       7
<PAGE>   8
this Section 10, with a copy to Robinson Silverman Pearce Aronsohn & Berman LLP,
1290 Avenue of the Americas, New York, New York 10104, attention Eric L. Cohen,
Esq.

     12. Warrant Agent. The Company shall serve as warrant agent under this
Warrant. The Company may appoint a new warrant agent upon notice to the Holder
in accordance with Section 10. Any corporation into which the Company may be
merged or any corporation resulting from any consolidation to which the Company
shall be a party or any corporation to which the Company transfers substantially
all of its corporate assets shall be a successor warrant agent under this
Warrant without any further act. Any such successor warrant agent shall promptly
cause notice of its succession as warrant agent to be mailed (by first class
mail, postage prepaid) to the Holder at the Holder's last address as shown on
the Warrant Register.

     13. Miscellaneous.

         (a) This Warrant shall be binding on and inure to the benefit of the
parties hereto and their respective successors and permitted assigns. This
Warrant may be amended only in writing signed by the Company and the Holder and
their successors and assigns.

         (b) Subject to Section 12(a), above, nothing in this Warrant shall be
construed to give to any person or corporation other than the Company and the
Holder any legal or equitable right, remedy or cause under this Warrant. This
Warrant shall inure to the sole and exclusive benefit of the Company and the
Holder.

         (c) The corporate laws of the State of Delaware shall govern all issues
concerning the relative rights of the Company and its stockholders. All other
questions concerning the construction, validity, enforcement and interpretation
of this Warrant shall be governed by and construed and enforced in accordance
with the internal laws of the State of New York, without regard to the
principles of conflicts of law thereof. The Company and the Holder hereby
irrevocably submit to the exclusive jurisdiction of the state and federal courts
sitting in the City of New York, borough of Manhattan, for the adjudication of
any dispute hereunder or in connection herewith or with any transaction
contemplated hereby or discussed herein, and hereby irrevocably waive, and agree
not to assert in any suit, action or proceeding, any claim that it is not
personally subject to the jurisdiction of any such court, or that such suit,
action or proceeding is improper. Each of the Company and the Holder hereby
irrevocably waives personal service of process and consents to process being
served in any such suit, action or proceeding by receiving a copy thereof sent
to the Company at the address in effect for notices to it under this instrument
and agrees that such service shall constitute good and sufficient service of
process and notice thereof. Nothing

                                       8
<PAGE>   9
contained herein shall be deemed to limit in any way any right to serve process
in any manner permitted by law.

         (d) The headings herein are for convenience only, do not constitute a
part of this Warrant and shall not be deemed to limit or affect any of the
provisions hereof.

         (e) In case any one or more of the provisions of this Warrant shall be
invalid or unenforceable in any respect, the validity and enforceability of the
remaining terms and provisions of this Warrant shall not in any way be affected
or impaired thereby and the parties will attempt in good faith to agree upon a
valid and enforceable provision which shall be a commercially reasonable
substitute therefor, and upon so agreeing, shall incorporate such substitute
provision in this Warrant.

     IN WITNESS WHEREOF, the Company has caused this Warrant to be duly executed
by its authorized officer as of the date first indicated above.

                                    NEOTHERAPEUTICS, INC.

                                    By: /s/ Samuel Gulko
                                        --------------------------------------
                                        Samuel Gulko
                                        Chief Financial Officer

                                       9
<PAGE>   10
                          FORM OF ELECTION TO PURCHASE

(To be executed by the Holder to exercise the right to purchase shares of Common
Stock under the foregoing Warrant)

To NeoTherapeutics, Inc.:

     In accordance with the Warrant enclosed with this Form of Election to
Purchase, the undersigned hereby irrevocably elects to purchase __________
shares of common stock ("Common Stock"), $.001 par value per share, of
NeoTherapeutics, Inc. and if such Holder is not utilizing the Cashless Exercise
provisions set forth in the Warrant, encloses herewith $__________ in cash,
certified or official bank check or checks, which sum represents the aggregate
Exercise Price (as defined in the Warrant) for the number of shares of Common
Stock to which this Form of Election to Purchase relates, together with any
applicable taxes payable by the undersigned pursuant to the Warrant.

     The undersigned requests that certificates for the shares of Common Stock
issuable upon this exercise be issued in the name of

                                    PLEASE INSERT SOCIAL SECURITY OR
                                    TAX IDENTIFICATION NUMBER

                                    --------------------------------------------

--------------------------------------------------------------------------------
                       (Please print name and address)

      If the number of shares of Common Stock issuable upon this exercise shall
not be all of the shares of Common Stock which the undersigned is entitled to
purchase in accordance with the enclosed Warrant, the undersigned requests that
a New Warrant (as defined in the Warrant) evidencing the right to purchase the
shares of Common Stock not issuable pursuant to the exercise evidenced hereby be
issued in the name of and delivered to:

--------------------------------------------------------------------------------
                       (Please print name and address)

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

Dated:  __________, ____            Name of Holder:

                                    (Print)
                                             ---------------------------------

                                    (By:)
                                           -----------------------------------

                                    (Name:)
                                    (Title:)
                                    (Signature must conform in all respects
                                    to name of holder as specified on the
                                    face of the Warrant)
<PAGE>   11
                              FORM OF ASSIGNMENT

          [To be completed and signed only upon transfer of Warrant]

      FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers
unto ____________________ the right represented by the Warrant enclosed with
this Form of Assignment to purchase __________ shares of Common Stock of
NeoTherapeutics, Inc. to which the Warrant relates and appoints
____________________ attorney to transfer said right on the books of
NeoTherapeutics, Inc. with full power of substitution in the premises.

Dated:  __________, ____

                                    ---------------------------------------
                                    (Signature must conform in all respects
                                    to name of holder as specified on the
                                    face of the Warrant)

                                    ---------------------------------------
                                    Address of Transferee

                                    ---------------------------------------

                                    ---------------------------------------

In the presence of:

--------------------------

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