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                                                                    EXHIBIT 4.11


                          SECURITIES PURCHASE AGREEMENT

                                      Among

                              NEOTHERAPEUTICS, INC.

                                       and

                         THE INVESTORS SIGNATORY HERETO




                         Dated as of September 29, 2000
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         SECURITIES PURCHASE AGREEMENT (this "Agreement"), dated as of September
29, 2000, among NeoTherapeutics Inc., a Delaware corporation (the "Company"),
and the investors signatory hereto on the date hereof (each such investor is a
"Purchaser" and all such investors are, collectively, the "Purchasers").

         WHEREAS, subject to the terms and conditions set forth in this
Agreement, the Company desires to issue and sell to the Purchasers and the
Purchasers, severally and not jointly, desire to purchase from the Company,
shares of the Company's common stock, $.001 par value per share (the "Common
Stock"), and certain other securities of the Company as more fully described in
this Agreement.

         NOW, THEREFORE, IN CONSIDERATION of the mutual covenants contained in
this Agreement, and for other good and valuable consideration the receipt and
adequacy are hereby acknowledged, the Company and the Purchasers agree as
follows:


                                    ARTICLE I
                                PURCHASE AND SALE

         1.1      The Closing.

                  (a) The Closing. (i) Subject to the terms and conditions set
forth in this Agreement, the Company shall issue and sell to the Purchasers and
the Purchasers shall purchase an aggregate of 968,524 shares of Common Stock
(the "Shares") for an aggregate purchase price of $8,000,000. The closing of the
purchase and sale of the Shares (the "Closing") shall take place at the offices
of Robinson Silverman Pearce Aronsohn & Berman LLP ("Robinson Silverman"), 1290
Avenue of the Americas, New York, New York 10104, immediately following the
execution hereof or such later date as the parties shall agree. The date of the
Closing is hereinafter referred to as the "Closing Date."

                           (ii) At the Closing, the parties shall deliver or
shall cause to be delivered the following: (A) the Company shall deliver to each
Purchaser: (1) a stock certificate representing the number of Shares indicated
below such Purchaser's name on the signature page of this Agreement, registered
in the name of such Purchaser, (2) a Common Stock purchase warrant, in the form
of Exhibit A, registered in the name of such Purchaser, pursuant to which such
Purchaser shall have the right to acquire shares of Common Stock upon the terms
and in such number as set forth therein (each an "Adjustable Warrant"), (3) a
Common Stock purchase warrant, in the form of Exhibit B, registered in the name
of such Purchaser, pursuant to which such Purchaser shall have the right to
acquire the number of shares of Common Stock indicated below such Purchaser's
name on the signature page of this Agreement, upon the terms set forth therein,
at an exercise price per share (subject to adjustment as provided therein) of
$10.13 (each, a "Closing Warrant" and together with the Adjustable Warrants, the
"Warrants"), (4) the legal opinion of Latham & Watkins, outside counsel to the
Company, substantially in the form of Exhibit C, and (5) all other documents,
instruments and writings required to be delivered at or prior to the Closing by
the Company pursuant to this Agreement, including an executed Registration
Rights Agreement, dated the date hereof, among the Company and the Purchasers,
in the form of Exhibit D (the "Registration Rights
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Agreement"), and the Transfer Agent Instructions, in the form of Exhibit E,
delivered to and acknowledged by the Company's transfer agent (the "Transfer
Agent Instructions"); and (B) each Purchaser shall deliver to the Company (1)
the purchase price indicated below such Purchaser's name on the signature page
to this Agreement in United States dollars in immediately available funds by
wire transfer to an account designated for such purpose prior to the Closing
Date in writing by the Company, and (2) all documents, instruments and writings
required to have been delivered at or prior to the Closing Date by such
Purchaser pursuant to this Agreement, including an executed Registration Rights
Agreement.

                  1.2 Certain Defined Terms. For purposes of this
Agreement,"Trading Day" and "Per Share Market Value" shall have the meanings set
forth in Exhibit A and "Business Day" shall mean any day except Saturday, Sunday
and any day which shall be a federal legal holiday or a day on which banking
institutions in the State of New York and the State of California generally are
authorized or required by law or other governmental action to close. A "Person"
means an individual or corporation, partnership, trust, incorporated or
unincorporated association, joint venture, limited liability company, joint
stock company, government (or an agency or subdivision thereof) or other entity
of any kind


                                   ARTICLE II
                         REPRESENTATIONS AND WARRANTIES

         2.1 Representations and Warranties of the Company. The Company hereby
makes the following representations and warranties to the Purchasers:

                  (a) Organization and Qualification. The Company is a
corporation duly incorporated, validly existing and in good standing under the
laws of the State of Delaware, with the requisite corporate power and authority
to own and use its properties and assets and to carry on its business as
currently conducted. The Company has no subsidiaries other than as set forth in
Schedule 2.1(a) (collectively, the "Subsidiaries"). Each of the Subsidiaries is
an entity, duly organized, validly existing and in good standing under the laws
of the jurisdiction of its incorporation or organization (as applicable), with
the requisite corporate power and authority to own and use its properties and
assets and to carry on its business as currently conducted. Each of the Company
and the Subsidiaries is duly qualified to do business and is in good standing as
a foreign corporation or other entity in each jurisdiction in which the nature
of the business conducted or property owned by it makes such qualification
necessary, except where the failure to be so qualified or in good standing, as
the case may be, could not, individually or in the aggregate, (x) adversely
affect the legality, validity or enforceability of the Securities (as defined
below) or any of this Agreement, the Registration Rights Agreement, the Transfer
Agent Instructions or the Warrants (collectively, the "Transaction Documents"),
(y) have or result in a material adverse effect on the results of operations,
assets, prospects, or condition (financial or otherwise) of the Company and the
Subsidiaries, taken as a whole, or (z) adversely impair the Company's ability to
perform fully on a timely basis its obligations under any of the Transaction
Documents (any of (x), (y) or (z), a "Material Adverse Effect").


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                  (b) Authorization; Enforcement. The Company has the requisite
corporate power and authority to enter into and to consummate the transactions
contemplated by each of the Transaction Documents and otherwise to carry out its
obligations thereunder. The execution and delivery of each of the Transaction
Documents by the Company and the consummation by it of the transactions
contemplated thereby have been duly authorized by all necessary corporate action
on the part of the Company and no further action is required by the Company.
Each of the Transaction Documents has been duly executed by the Company and,
when delivered (or filed, as the case may be) in accordance with the terms
hereof, will constitute the valid and binding obligation of the Company
enforceable against the Company in accordance with its terms. Neither the
Company nor any Subsidiary is in violation of any of the provisions of its
respective certificate of incorporation, by-laws or other charter or
organizational documents.

                  (c) Capitalization. The number of authorized, issued and
outstanding capital stock of the Company is set forth in Schedule 2.1(c). Except
as disclosed in Schedule 2.1(c), the Company owns all of the capital stock of
each Subsidiary. No securities of the Company or any Subsidiary are entitled to
preemptive or similar rights, nor is any holder of securities of the Company or
any Subsidiary entitled to preemptive or similar rights arising out of any
agreement or understanding with the Company or any Subsidiary by virtue of any
of the Transaction Documents. Except as disclosed in Schedule 2.1(c), there are
no outstanding options, warrants, script rights to subscribe to, calls or
commitments of any character whatsoever relating to, or securities, except as a
result of the purchase and sale of the Securities, or rights or obligations
convertible into or exchangeable for, or giving any Person any right to
subscribe for or acquire, any shares of Common Stock, or contracts, commitments,
understandings, or arrangements by which the Company or any Subsidiary is or may
become bound to issue additional shares of Common Stock, or securities or rights
convertible or exchangeable into shares of Common Stock. To the knowledge of the
Company, except as specifically disclosed in the SEC Reports (as defined below)
or Schedule 2.1(c), no Person or group of related Persons beneficially owns (as
determined pursuant to Rule 13d-3 promulgated under the Securities Exchange Act
of 1934, as amended (the "Exchange Act")), or has the right to acquire by
agreement with or by obligation binding upon the Company, beneficial ownership
of in excess of 5% of the Common Stock.

                  (d) Issuance of the Securities. The Securities are duly
authorized and, when issued and paid for in accordance with the terms hereof and
the Warrants, shall have been duly and validly issued, fully paid and
nonassessable, free and clear of all liens, encumbrances and rights of first
refusal of any kind (collectively, "Liens"). The Company has reserved a number
of duly authorized number of shares of Common Stock for issuance hereunder upon
exercise of the Warrants that is not less than the sum of (i) the aggregate
number of Shares to be issued hereunder; (ii) the maximum number of Underlying
Shares (as defined below) issuable upon exercise of the Adjustable Warrants,
assuming that the Per Share Market Value utilized to determine the number of
such Underlying Shares is 50% of the Per Share Market Value on the Trading Day
immediately preceding the Closing Date; and (iii) the number of Underlying
Shares issuable upon exercise in full of the Closing Warrants (such number of
shares of Common Stock as contemplated in clauses (i), (ii) and (iii), the
"Initial Minimum"). The shares of Common Stock issuable upon exercise of the
Warrants are referred to herein as the "Underlying Shares." The Shares, the
Warrants and the Underlying Shares are collectively referred to herein as, the
"Securities."


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                  (e) No Conflicts. The execution, delivery and performance of
the Transaction Documents by the Company and the consummation by the Company of
the transactions contemplated thereby do not and will not (i) conflict with or
violate any provision of the Company's or any Subsidiary's certificate of
incorporation, bylaws or other charter documents (each as amended through the
date hereof), or (ii) subject to obtaining the Required Approvals (as defined
below), conflict with, or constitute a default (or an event which with notice or
lapse of time or both would become a default) under, or give to others any
rights of termination, amendment, acceleration or cancellation (with or without
notice, lapse of time or both) of, any agreement, credit facility, debt or other
instrument (evidencing a Company or Subsidiary debt or otherwise) or other
understanding to which the Company or any Subsidiary is a party or by which any
property or asset of the Company or any Subsidiary is bound or affected, or
(iii) result in a violation of any law, rule, regulation, order, judgment,
injunction, decree or other restriction of any court or governmental authority
to which the Company or a Subsidiary is subject (including federal and state
securities laws and regulations), or by which any property or asset of the
Company or a Subsidiary is bound or affected; except in the case of each of
clauses (ii) and (iii), as could not, individually or in the aggregate, have or
result in a Material Adverse Effect. The business of the Company is not being
conducted in violation of any law, ordinance or regulation of any governmental
authority, except for violations which, individually or in the aggregate, could
not have or result in a Material Adverse Effect.

                  (f) Filings, Consents and Approvals. Neither the Company nor
any Subsidiary is required to obtain any consent, waiver, authorization or order
of, give any notice to, or make any filing or registration with, any court or
other federal, state, local or other governmental authority or other Person in
connection with the execution, delivery and performance by the Company of the
Transaction Documents, other than (i) the filings required pursuant to Section
3.10, (ii) the filing with the Securities and Exchange Commission (the
"Commission") of one or more registration statements meeting the requirements
set forth in the Registration Rights Agreement and covering the resale of the
Shares and the Underlying Shares by the Purchasers (collectively, the
"Underlying Shares Registration Statement"), (iii) the application(s) to the
Nasdaq National Market ("NASDAQ") for the listing of the Shares and the
Underlying Shares with the NASDAQ (and with any other national securities
exchange of market in which the Common Stock is then listed) in the time and
manner required thereby , (vi) applicable Blue Sky filings, and (v) in all other
cases where the failure to obtain such consent, waiver, authorization or order,
or to give such notice or make such filing or registration could not have or
result in, individually or in the aggregate, a Material Adverse Effect (the
items described in clauses (i)-(vi) are collectively, the "Required Approvals").

                  (g) Litigation; Proceedings. Except as specified in the SEC
Reports and as set forth in Schedule 2.1(g), there is no action, suit, notice of
violation, proceeding or investigation pending or, to the knowledge of the
Company, threatened against or affecting the Company or any of its Subsidiaries
or any of their respective properties before or by any court, governmental or
administrative agency or regulatory authority (federal, state, county, local or
foreign) which (i) adversely affects or challenges the legality, validity or
enforceability of any of the Transaction Documents or the Securities or (ii)
could, individually or in the aggregate, have or result in a Material Adverse
Effect.


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                  (h) No Default or Violation. Neither the Company nor any
Subsidiary (i) is in default under or in violation of (and no event has occurred
which has not been waived which, with notice or lapse of time or both, would
result in a default by the Company or any Subsidiary under), nor has the Company
or any Subsidiary received notice of a claim that it is in default under or that
it is in violation of, any indenture, loan or credit agreement or any other
agreement or instrument to which it is a party or by which it or any of its
properties is bound (whether or not such default or violation has been waived),
(ii) is in violation of any order of any court, arbitrator or governmental body,
or (iii) is in violation of any statute, rule or regulation of any governmental
authority, except as could not individually or in the aggregate, have or result
in a Material Adverse Effect.

                  (i) Private Offering. Assuming the accuracy of the
representations and warranties of the Purchasers set forth in Sections
2.2(b)-(g), the offer, issuance and sale of the Securities to the Purchasers as
contemplated hereby are exempt from the registration requirements of the
Securities Act of 1933, as amended (the "Securities Act"). Neither the Company
nor any Person acting on its behalf has taken or is, to the knowledge of the
Company, contemplating taking any action which could subject the offering,
issuance or sale of the Securities to the registration requirements of the
Securities Act including soliciting any offer to buy or sell the Securities by
means of any form of general solicitation or advertising.

                  (j) SEC Reports; Financial Statements. The Company has filed
all reports required to be filed by it under the Securities Act of 1933, as
amended (the "Securities Act"), and the Exchange Act for the two years preceding
the date hereof (or such shorter period as the Company was required by law to
file such material) (the foregoing materials being collectively referred to
herein as the "SEC Reports" and, together with the Schedules to this Agreement
the "Disclosure Materials") on a timely basis or has received a valid extension
of such time of filing and has filed any such SEC Reports prior to the
expiration of any such extension. As of their respective dates, the SEC Reports
complied in all material respects with the requirements of the Securities Act
and the Exchange Act and the rules and regulations of the Commission promulgated
thereunder, and none of the SEC Reports, when filed, contained any untrue
statement of a material fact or omitted to state a material fact required to be
stated therein or necessary in order to make the statements therein, in light of
the circumstances under which they were made, not misleading. All material
agreements to which the Company is a party or to which the property or assets of
the Company are subject have been filed as exhibits to the SEC Reports. The
financial statements of the Company included in the SEC Reports comply in all
material respects with applicable accounting requirements and the rules and
regulations of the Commission with respect thereto as in effect at the time of
filing. Such financial statements have been prepared in accordance with
generally accepted accounting principles applied on a consistent basis during
the periods involved ("GAAP"), except as may be otherwise specified in such
financial statements or the notes thereto, and fairly present in all material
respects the financial position of the Company and its consolidated subsidiaries
as of and for the dates thereof and the results of operations and cash flows for
the periods then ended, subject, in the case of unaudited statements, to normal,
immaterial, year-end audit adjustments. Since September 30,1999, except as
specifically disclosed in the SEC Reports, (a) there has been no event,
occurrence or development that has or that could result in a Material Adverse
Effect, (b) the Company has not incurred any liabilities (contingent or
otherwise) other than (x) liabilities incurred in the ordinary course of
business consistent with past practice and (y) liabilities not required to be
reflected in the Company's financial statements pursuant to GAAP or required to
be disclosed in filings made with


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the Commission, (c) the Company has not altered its method of accounting or the
identity of its auditors and (d) the Company has not declared or made any
payment or distribution of cash or other property to its stockholders or
officers or directors (other than in compliance with existing Company stock or
stock option plans and existing agreements and terms of employment) with respect
to its capital stock, or purchased, redeemed (or made any agreements to purchase
or redeem) any shares of its capital stock.

                  (k) Investment Company. The Company is not, and is not an
Affiliate (as defined in Rule 405 under the Securities Act) of, an "investment
company" within the meaning of the Investment Company Act of 1940, as amended.

                  (l) Certain Fees. Except as are payable to Brighton Capital,
Ltd. by the Company, no fees or commissions will be payable by the Company to
any broker, financial advisor or consultant, finder, placement agent, investment
banker, bank or other person, with respect to the transactions contemplated by
this Agreement. The Purchasers shall have no obligation with respect to any fees
or with respect to any claims made by or on behalf of other Persons for fees of
a type contemplated in this Section that may be due in connection with the
transactions contemplated by this Agreement. The Company shall indemnify and
hold harmless the Purchasers, their employees, officers, directors, agents, and
partners, and its respective Affiliates, from and against all claims, losses,
damages, costs (including the costs of preparation and attorney's fees) and
expenses suffered in respect of any such claimed or existing fees, as such fees
and expenses are incurred.

                  (m) Form S-3 Eligibility. The Company is eligible to register
its Common Stock for resale under Form S-3 promulgated under the Securities Act.

                  (n) Listing and Maintenance Requirements. The Company has not,
in the two years preceding the date hereof received notice (written or oral)
from the NASDAQ or any other stock exchange, market or trading facility on which
the Common Stock is or has been listed (or on which it has been quoted) to the
effect that the Company is not in compliance with the listing or maintenance
requirements of such exchange, market or trading facility. The Company is, and
has no reason to believe that it will not in the foreseeable future continue to
be, in compliance with all such listing and maintenance requirements.

                  (o) Patents and Trademarks. The Company and its Subsidiaries
have, or have rights to use, all patents, patent applications, trademarks,
trademark applications, service marks, trade names, copyrights, licenses and
rights (collectively, the "Intellectual Property Rights") which are necessary or
material for use in connection with their respective business as described in
the SEC Reports and as contemplated to be conducted, and which the failure to so
have would have a Material Adverse Effect. Neither the Company nor any
Subsidiary has received a written notice that the Intellectual Property Rights
used by the Company or its Subsidiaries violates or infringes upon the rights of
any Person, to the best knowledge of the Company. All such Intellectual Property
Rights are enforceable and there is no existing infringement by another Person
of any of the Intellectual Property Rights.

                  (p) Regulatory Permits. The Company and its Subsidiaries
possess all certificates, authorizations and permits issued by the appropriate
federal, state or foreign regulatory


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authorities necessary to conduct their respective businesses as described in the
SEC Reports, except where the failure to possess such permits could not,
individually or in the aggregate, have or result in a Material Adverse Effect
("Material Permits"), and neither the Company nor any such Subsidiary has
received any notice of proceedings relating to the revocation or modification of
any Material Permit.

                  (q) Title. Except as set forth in Schedule 2.1(q), the Company
and the Subsidiaries have good and marketable title in fee simple to all real
property and personal property owned by them which is material to the business
of the Company and its Subsidiaries, in each case free and clear of all Liens,
except for Liens as do not materially affect the value of such property and do
not materially interfere with the use made and proposed to be made of such
property by the Company and its Subsidiaries. Any real property and facilities
held under lease by the Company and its Subsidiaries are held by them under
valid, subsisting and enforceable leases with such exceptions as are not
material and do not materially interfere with the use made and proposed to be
made of such property and buildings by the Company and its Subsidiaries.

                  (r) Disclosure. The Company confirms that it has not provided
the Purchasers or their agents or counsel with any information that constitutes
or might constitute material non-public information. The Company understands and
confirms that the Purchasers shall be relying on the foregoing representations
in effecting transactions in securities of the Company. All disclosure provided
to the Purchasers regarding the Company, its business and the transactions
contemplated hereby, including the Schedules to this Agreement, furnished by or
on behalf of the Company are true and correct and do not contain any untrue
statement of a material fact or omit to state any material fact required to be
stated therein or necessary in order to make the statements therein, in light of
the circumstances under which they were made, not misleading.

         2.2 Representations and Warranties of the Purchasers. Each Purchaser
hereby for itself and for no other Purchaser, represents and warrants to the
Company as follows:

                  (a) Organization; Authority. Such Purchaser is an entity duly
organized, validly existing and in good standing under the laws of the
jurisdiction of its organization with the requisite corporate or partnership
power and authority to enter into and to consummate the transactions
contemplated by the Transaction Documents and otherwise to carry out its
obligations thereunder. The purchase by such Purchaser of the Securities
hereunder has been duly authorized by all necessary action on the part of such
Purchaser. Each of this Agreement and the Registration Rights Agreement has been
duly executed by such Purchaser, and when delivered by such Purchaser in
accordance with the terms hereof, will constitute the valid and legally binding
obligation of such Purchaser, enforceable against it in accordance with its
terms.

                  (b) Investment Intent. Such Purchaser is acquiring the
Securities as principal for its own account for investment purposes only and not
with a view to or for distributing or reselling such Securities or any part
thereof, without prejudice, however, to such Purchaser's right, subject to the
provisions of this Agreement and the Registration Rights Agreement, at all times
to sell or otherwise dispose of all or any part of such Securities pursuant to
an effective registration statement under the Securities Act and in compliance
with applicable federal and state securities laws or under


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an exemption from such registration. Nothing contained herein shall be deemed a
representation or warranty by such Purchaser to hold Securities for any amount
of time.

                  (c) Purchaser Status. At the time such Purchaser was offered
the Securities, it was, and at the date hereof it is, and at each exercise date
under the Warrants, it will be, a qualified institutional buyer as defined in
Rule 144A promulgated under the Securities Act. Such Purchaser has not been
formed solely for the purpose of acquiring the Securities.

                  (d) Experience of such Purchaser. Such Purchaser, either alone
or together with its representatives, has such knowledge, sophistication and
experience in business and financial matters so as to be capable of evaluating
the merits and risks of the prospective investment in the Securities, and has so
evaluated the merits and risks of such investment.

                  (e) Ability of Purchaser to Bear Risk of Investment. Such
Purchaser is able to bear the economic risk of an investment in the Securities
and, at the present time, is able to afford a complete loss of such investment.

                  (f) Access to Information. Such Purchaser acknowledges that it
has reviewed the Disclosure Materials and has been afforded (i) the opportunity
to ask such questions as it has deemed necessary of, and to receive answers
from, representatives of the Company concerning the terms and conditions of the
offering of the Securities and the merits and risks of investing in the
Securities; (ii) access to information about the Company and the Company's
financial condition, results of operations, business, properties, management and
prospects sufficient to enable it to evaluate its investment; and (iii) the
opportunity to obtain such additional information which the Company possesses or
can acquire without unreasonable effort or expense that is necessary to make an
informed investment decision with respect to the investment. Neither such
inquiries nor any other investigation conducted by or on behalf of any Purchaser
or its representatives or counsel shall modify, amend or affect a Purchaser's
right to rely on the truth, accuracy and completeness of the Disclosure
Materials and the Company's representations and warranties contained in the
Transaction Documents.

                  (g) General Solicitation. Such Purchaser is not purchasing the
Securities as a result of or subsequent to any advertisement, article, notice or
other communication regarding the Securities published in any newspaper,
magazine or similar media or broadcast over television or radio or presented at
any seminar or any other general solicitation or general advertisement.

                  (h) Reliance. Such Purchaser understands and acknowledges that
(i) the Securities are being offered and sold to it without registration under
the Securities Act in a private placement that is exempt from the registration
provisions of the Securities Act and (ii) the availability of such exemption,
depends in part on, and the Company will rely upon the accuracy and truthfulness
of, the foregoing representations and such Purchaser hereby consents to such
reliance.
                  The Company acknowledges and agrees that no Purchaser makes or
has made representations or warranties with respect to the transactions
contemplated hereby other than those specifically set forth in this Section 2.2.


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                                   ARTICLE III
                         OTHER AGREEMENTS OF THE PARTIES


         3.1 Transfer Restrictions. (a) Securities may only be disposed of
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, and in
compliance with any applicable federal and state securities laws. In connection
with any transfer of Securities other than pursuant to an effective registration
statement or to the Company, except as otherwise set forth herein, 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 under the Securities Act. Notwithstanding
the foregoing, the Company, without requiring a legal opinion as described in
the immediately preceding sentence, hereby consents to and agrees to register on
the books of the Company and with any transfer agent for the securities of the
Company any transfer of Securities by a Purchaser to an Affiliate of such
Purchaser or to one or more funds or managed accounts under common management
with such Purchaser, and any transfer among any such Affiliates or one or more
funds or managed accounts, provided (i) that the transferee certifies to the
Company that it is an "accredited investor" within the meaning of Rule 501(a)
under the Securities Act, (ii) that it is acquiring the Securities solely for
investment purposes (subject to the qualifications hereof), and (iii) that any
such transferee shall agree in writing to be bound by the terms of this
Agreement and shall have the rights of the Purchaser under this Agreement and
the Registration Rights Agreement.

                  (b) The Purchasers agree to the imprinting, so long as is
required by this Section 3.1(b), of the following legend on the Securities:

                  [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 OR SOLD EXCEPT PURSUANT TO AN EFFECTIVE
         REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN
         AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE
         REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH
         APPLICABLE STATE SECURITIES LAWS.

                  Neither Shares nor Underlying Shares shall contain the legend
set forth above nor any other legend at any time while an Underlying Shares
Registration Statement covering such Shares or Underlying Shares (as applicable)
is effective under the Securities Act or, in the event there is not an effective
Registration Statement, covering such Shares or Underlying Shares (as
applicable) at such time if such legend is not required under applicable
requirements of the Securities Act (including judicial interpretations and
pronouncements issued by the staff of the Commission). The Company shall cause
its counsel to issue the legal opinion included in the Transfer Agent
Instructions to the Company's transfer agent on the day that such Underlying
Shares Registration Statement is declared effective by the Commission. The
Company agrees that with respect to any


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Shares or Underlying Shares that are issued with a legend in accordance with
this Section 3.1(b), it will, within three (3) Trading Days after request
therefor by a Purchaser and the surrender by such Purchaser of the certificate
representing the applicable Shares or Underlying Shares, provide such Purchaser
with a certificate or certificates representing such Shares or Underlying
Shares, free from such legend at such time as such legend would not have been
required under this Section 3.1(b) had such issuance occurred on the date of
such request. The Company may not make any notation on its records or give
instructions to any transfer agent of the Company which enlarge the restrictions
of transfer set forth in this Section. Each Purchaser will comply with the
prospectus delivery requirements of the Securities Act as applicable to it in
connection with sales of Registrable Securities (as defined in the Registration
Rights Agreement) pursuant to an Underlying Shares Registration Statement.

         3.2 Acknowledgment of Dilution. The Company acknowledges that the
issuance of Underlying Shares upon exercise of the Warrants will result in
dilution of the outstanding shares of Common Stock, which dilution may be
substantial under certain market conditions. The Company further acknowledges
that its obligation to issue Underlying Shares upon exercise of the Warrants
pursuant to the terms thereof is unconditional and absolute regardless of the
effect of any such dilution.

         3.3 Furnishing of Information. As long as the Purchasers own
Securities, the Company covenants to file timely (or obtain extensions in
respect thereof and file within the applicable grace period) all reports
required to be filed by the Company after the date hereof pursuant to the
Exchange Act. So long as the Purchasers own Securities, if the Company is not
required to file reports pursuant to such laws, it will prepare and furnish to
the Purchasers and make publicly available in accordance with Rule 144(c)
promulgated under the Securities Act such information as is required for the
Purchasers to sell the Securities under Rule 144 promulgated under the
Securities Act. The Company further covenants that it will take such further
action as any holder of Securities may reasonably request, all to the extent
required from time to time to enable such Person to sell Underlying Shares
without registration under the Securities Act within the limitation of the
exemptions provided by Rule 144 promulgated under the Securities Act, including
the legal opinion referenced above in this Section. Upon the request of any such
Person, the Company shall deliver to such Person a written certification of a
duly authorized officer as to whether it has complied with such requirements.

         3.4 Integration. The Company shall not, and shall use its best efforts
to ensure that, no Affiliate shall, sell, offer for sale or solicit offers to
buy or otherwise negotiate in respect of any security (as defined in Section 2
of the Securities Act) that would be integrated with the offer or sale of the
Securities in a manner that would require the registration under the Securities
Act of the sale of the Securities to the Purchasers or that would be integrated
with the offer or sale of the Securities for purposes of the rules and
regulations of the Nasdaq Stock Market.

         3.5 Increase in Authorized Shares. Subject to Section 10(c) of the
Adjustable Warrant, if on any date the Company would be, if a notice of exercise
were to be delivered on such date, precluded from issuing 200% of the number of
Underlying Shares as would then be issuable upon exercise in full of the
Adjustable Warrants (the "Current Required Minimum") due to the unavailability
of a sufficient number of authorized but unissued or reserved shares of Common


                                      -11-
   12
Stock, then the Board of Directors of the Company shall promptly (and in any
case, within 60 Business Days from such date) prepare and mail to the
stockholders of the Company proxy materials requesting authorization to amend
the Company's certificate of incorporation to increase the number of shares of
Common Stock which the Company is authorized to issue to at least such number of
shares as is reasonably adequate to enable the Company to comply with its
issuance, exercise and reservation of shares obligations as set forth in this
Agreement and the Warrants (the sum of (x) the number of shares of Common Stock
then outstanding plus all shares of Common Stock issuable upon exercise of all
outstanding options, warrants and convertible instruments other than the
Adjustable Warrants, and (y) the Current Required Minimum, shall be a reasonable
number). In connection therewith, the Board of Directors shall (a) adopt proper
resolutions authorizing such increase, (b) recommend to and otherwise use its
best efforts to promptly and duly obtain stockholder approval to carry out such
resolutions (and hold a special meeting of the stockholders no later than the
earlier to occur of the 60th day after delivery of the proxy materials relating
to such meeting and the 90th day after request by a holder of Warrants to issue
the number of Underlying Shares in accordance with the terms hereof) and (c)
within five (5) Business Days of obtaining such stockholder authorization, file
an appropriate amendment to the Company's certificate of incorporation to
evidence such increase.

         3.6 Reservation and Listing of Underlying Shares. (a) The Company shall
(i) in the time and manner required by the NASDAQ and such other national
securities exchange or market or trading or quotation facility on which the
Common Stock is then listed for trading, prepare and file with the NASDAQ (and
such other national securities exchange or market or trading or quotation
facility on which the Common Stock is then listed for trading) an additional
shares listing application covering a number of shares of Common Stock which is
not less than the Initial Minimum, (ii) take all steps necessary to cause such
shares of Common Stock to be approved for listing in the NASDAQ (as well as on
any such other national securities exchange or market or trading or quotation
facility on which the Common Stock is then listed) as soon as possible
thereafter, and (iii) provide to the Purchasers evidence of such listing, and
the Company shall maintain the listing of its Common Stock thereon. If the
number of Underlying Shares issuable upon exercise of the then unexercised
portion of the Adjustable Warrants exceeds 85% of the number of Underlying
Shares previously listed on account thereof with NASDAQ (and any such other
required exchanges), then the Company shall take the necessary actions to list
immediately a number of Underlying Shares as equals no less than the then
Current Required Minimum with respect thereto.

                  (b) The Company shall maintain a reserve of shares of Common
Stock for issuance upon exercise in full of the Warrants in accordance with the
Warrants, in such amount as may be required to fulfill its obligations in full
under the Warrants, which reserve shall equal no less than the then Current
Required Minimum.

         3.7 Exercise Procedures. The Transfer Agent Instructions and Form of
Election to Purchase under the Warrants set forth the totality of the procedures
with respect to the exercise of the Warrants, including the form of legal
opinion, if necessary, that shall be rendered to the Company's transfer agent
and such other information and instructions as may be reasonably necessary to
enable the Purchasers to exercise the Warrants.


                                      -12-
   13
         3.8 Notice of Breaches. Each of the Company and the Purchasers shall
give prompt written notice to the other of any breach by it of any
representation, warranty or other agreement contained in any Transaction
Document, as well as any events or occurrences arising after the date hereof
which would reasonably be likely to cause any representation or warranty or
other agreement of such party, as the case may be, contained therein to be
incorrect or breached as of the Closing Date. However, no disclosure by a party
pursuant to this Section shall be deemed to cure any breach of any
representation, warranty or other agreement contained in any Transaction
Document.

         3.9      [Intentionally left blank]

         3.10 Certain Securities Laws Disclosures; Publicity. The Company shall:
(i) on the Closing Date, issue a press release acceptable to the Purchasers
disclosing the transactions contemplated hereby, (ii) file with the Commission a
Report on Form 8-K or Form 10-Q (as applicable) disclosing the transactions
contemplated hereby within ten (10) Business Days after the Closing Date, and
(iii) timely file with the Commission a Form D promulgated under the Securities
Act as required under Regulation D promulgated under the Securities Act and
provide a copy thereof to the Purchasers promptly after the filing thereof. The
Company shall, no less than two (2) Business Days prior to the filing of any
disclosure required by clauses (ii) and (iii) above, provide a copy thereof to
the Purchasers. The Company and the Purchasers shall consult with each other in
issuing any press releases or otherwise making public statements or filings and
other communications with the Commission or any regulatory agency or stock
market or trading facility with respect to the transactions contemplated hereby
and neither party shall issue any such press release or otherwise make any such
public statement, filings or other communications pertaining to the transactions
contemplated hereby without the prior written consent of the other, which
consent shall not be unreasonably withheld or delayed, except that no prior
consent shall be required if such disclosure is required by law or such consent
can not reasonably be expected to be received prior to the time required to
complete such filing or make such statement in accordance with such applicable
law, in which such case the disclosing party shall provide the other party with
prior notice of such public statement, filing or other communication.
Notwithstanding the foregoing, the Company shall not publicly disclose the name
of a Purchaser, or include the name of a Purchaser in any filing with the
Commission, or any regulatory agency, trading facility or stock market without
the prior written consent of such Purchaser, except to the extent such
disclosure is required by law, in which case the Company shall provide such
Purchaser with prior notice of such disclosure.

         3.11 Transfer of Intellectual Property Rights. Except in connection
with the sale of all or substantially all of the assets of the Company, prior to
the Second Vesting Date, the Company shall not sell or otherwise dispose of any
Intellectual Property Rights or allow any of the Intellectual Property Rights to
become subject to any Liens, or fail to renew such Intellectual Property Rights
(if renewable and it would otherwise lapse if not renewed), without the prior
written consent of the Purchasers. Notwithstanding the foregoing, the Company
may license the right to promote and use its Intellectual Property Rights to
Strategic Partners in the ordinary course of its business without the prior
consent of the Purchasers.

         3.12 Use of Proceeds. The Company shall use the net proceeds from the
sale of Securities hereunder for working capital purposes and not for the
satisfaction of any portion of the Company's debt, to redeem any Company equity
or equity-equivalent securities or to settle any outstanding


                                      -13-
   14
litigation, except as may be expressly permitted by the Transaction Documents.
Pending application of the proceeds of this placement in the manner permitted
hereby, the Company will invest such proceeds in interest bearing accounts
and/or short-term, investment grade interest bearing securities.

         3.13 Reimbursement. If any Purchaser, other than by reason of its gross
negligence or willful misconduct, becomes involved in any capacity in any
action, proceeding or investigation brought by or against any Person, including
stockholders of the Company, in connection with or as a result of the
consummation of the transactions contemplated by Transaction Documents, the
Company will reimburse such Purchaser for its reasonable legal and other
expenses (including the cost of any investigation and preparation and travel in
connection therewith) incurred in connection therewith, as such expenses are
incurred. In addition, other than with respect to any matter in which any of the
Purchasers is a named party, the Company will pay such Purchaser the charges, as
reasonably determined by such Purchaser, for the time of any officers or
employees of such Purchaser devoted to appearing and preparing to appear as
witnesses, assisting in preparation for hearings, trials or pretrial matters, or
otherwise with respect to inquiries, hearings, trials, and other proceedings
relating to the subject matter of this Agreement. The reimbursement obligations
of the Company under this paragraph shall be in addition to any liability which
the Company may otherwise have, shall extend upon the same terms and conditions
to any Affiliates of the Purchasers who are actually named in such action,
proceeding or investigation, and partners, directors, agents, employees and
controlling persons (if any), as the case may be, of the Purchasers and any such
Affiliate, and shall be binding upon and inure to the benefit of any successors,
assigns, heirs and personal representatives of the Company, the Purchasers and
any such Affiliate and any such Person. The Company also agrees that neither the
Purchasers nor any such Affiliates, partners, directors, agents, employees or
controlling persons shall have any liability to the Company or any Person
asserting claims on behalf of or in right of the Company in connection with or
as a result of the consummation of the Transaction Documents except to the
extent that any losses, claims, damages, liabilities or expenses incurred by the
Company result from the gross negligence or willful misconduct of the applicable
Purchaser or entity in connection with the transactions contemplated by this
Agreement.

         3.14 Shareholders Rights Plan. In the event that a shareholders rights
plan is adopted by the Company, no claim will be made or enforced by the Company
or any other Person that any Purchaser is an "Acquiring Person" under any such
plan or in any way could be deemed to trigger the provisions of such plan by
virtue of receiving Shares or Underlying Shares under the Transaction Documents.

         3.15 Certain Conversion Restrictions. During the thirty Trading Days
preceding each Vesting Date (as defined in the Adjustable Warrants), each
Purchaser shall not convert any convertible debenture of the Company or shares
of convertible preferred stock of the Company, in either case, owned by it.

         3.16 Waiver of Anti-dilution Rights. Each Purchaser hereby waives any
right to any adjustment to: (i) the purchase price, exercise price or conversion
price applicable to any rights, warrants, options or other securities of the
Company or debt that is convertible or exchangeable for securities of the
Company, held by such Purchaser or any affiliate of such Purchaser on the
Closing Date, or (ii) the number of shares of Common Stock issuable upon
exercise, conversion or exchange


                                      -14-
   15
of any rights, warrants, options or other securities of the Company or debt that
is convertible or exchangeable for securities of the Company, held by such
Purchaser or any affiliate of such Purchaser on the Closing Date, to the extent
that such adjustment would result from: (A) the issuance of the Shares or the
Warrants, (B) the operation of purchase price adjustments, reset provisions or
anti-dilution applicable to the Warrants, or (C) the issuance of shares of
Common Stock upon exercise of the Warrants. Each Purchaser represents and
warrants that it has the power and authority to give such waiver on behalf of
its affiliates, and agrees to indemnify the Company against any harm, damages,
losses or expenses that may be suffered or incurred by the Company as a direct
or indirect result of any failure of the waiver set forth in this Section 3.16
to be effective against any affiliate or transferee of such Purchaser.

                                   ARTICLE IV
                                  MISCELLANEOUS

                  4.1 Fees and Expenses. At the Closing the Company shall
reimburse the Purchasers for their legal fees and expenses incurred in
connection with the preparation and negotiation of the Transaction Documents by
paying to Robinson Silverman $25,000 for the preparation and negotiation of the
Transaction Documents. The $25,000 may be deducted from the proceeds of the
Purchase Price payable to the Company and paid directly by the Purchasers to
Robinson Silverman. Other than the amounts contemplated in the immediately
preceding sentence, and except as otherwise set forth in the Registration Rights
Agreement, each party shall pay the fees and expenses of its advisers, counsel,
accountants and other experts, if any, and all other expenses incurred by such
party incident to the negotiation, preparation, execution, delivery and
performance of this Agreement. The Company shall pay all stamp and other taxes
and duties levied in connection with the issuance of the Securities.

                  4.2 Entire Agreement; Amendments. The Transaction Documents,
together with the Exhibits and Schedules thereto contain the entire
understanding of the parties with respect to the subject matter hereof and
supersede all prior agreements and understandings, oral or written, with respect
to such matters, which the parties acknowledge have been merged into such
documents, exhibits and schedules.

                  4.3 Notices. Any and all notices or other communications or
deliveries required or permitted to be provided 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 8:00 p.m. (New
York City 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 Agreement later than 8:00 p.m. (New
York City time) on any date and earlier than 11:59 p.m. (New York City time) on
such date, (iii) the Business Day following the date of mailing, if sent by
nationally recognized overnight courier service, or (iv) if sent other than by
the methods set forth in (i)-(iii) of this Section 4.3, upon actual receipt by
the party to whom such notice is required to be given. The address for such
notices and communications shall be as follows:

         If to the Company:         NeoTherapeutics, Inc.
                                    157 Technology Drive


                                      -15-
   16
                                    Irvine, CA 92618
                                    Facsimile No.: (949) 788-6706
                                    Attn:  Chief Financial Officer

         With copies to:            Latham & Watkins
                                    650 Town Center Drive, Suite 2000
                                    Costa Mesa, CA 92661-1925
                                    Facsimile No.: (714) 755-8290
                                    Attn: Alan W. Pettis, Esq.

         If to a Purchaser:         To the address
                                    set forth under such
                                    Purchaser's name on the
                                    signature pages hereto.

or such other address as may be designated in writing hereafter, in the same
manner, by such Person.

                  4.4 Amendments; Waivers. No provision of this Agreement may be
waived or amended except in a written instrument signed, in the case of an
amendment, by both the Company and the Purchasers or, in the case of a waiver,
by the party against whom enforcement of any such waiver is sought. No waiver of
any default with respect to any provision, condition or requirement of this
Agreement shall be deemed to be a continuing waiver in the future or a waiver of
any other provision, condition or requirement hereof, nor shall any delay or
omission of either party to exercise any right hereunder in any manner impair
the exercise of any such right accruing to it thereafter.

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

                  4.6 Successors and Assigns. This Agreement shall be binding
upon and inure to the benefit of the parties and their successors and permitted
assigns. The Company may not assign this Agreement or any rights or obligations
hereunder without the prior written consent of the Purchasers. Except as set
forth in Section 3.1(a), the Purchasers may not assign this Agreement or any of
the rights or obligations hereunder without the consent of the Company.

                  4.7 No Third-Party Beneficiaries. This Agreement is intended
for the benefit of the parties hereto and their respective successors and
permitted assigns and is not for the benefit of, nor may any provision hereof be
enforced by, any other Person.

                  4.8 Governing Law. 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 the Transaction Documents 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. Each
party hereby irrevocably submits 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 (including with respect to
the enforcement of the any of the Transaction Documents), and hereby irrevocably
waives, and


                                      -16-
   17
agrees not to assert in any suit, action or proceeding, any claim that it is not
personally subject to the jurisdiction of any such court, that such suit, action
or proceeding is improper. Each party hereby irrevocably waives personal service
of process and consents to process being served in any such suit, action or
proceeding by mailing a copy thereof to such party at the address in effect for
notices to it under this Agreement and agrees that such service shall constitute
good and sufficient service of process and notice thereof. Nothing contained
herein shall be deemed to limit in any way any right to serve process in any
manner permitted by law.

                  4.9 Survival. The representations, warranties, agreements and
covenants contained herein shall survive the Closing and the delivery and
exercise of the Warrants.

                  4.10 Execution. This Agreement may be executed in two or more
counterparts, all of which when taken together shall be considered one and the
same agreement and shall become effective when counterparts have been signed by
each party and delivered to the other party, it being understood that both
parties need not sign the same counterpart. In the event that any signature is
delivered by facsimile transmission, such signature shall create a valid and
binding obligation of the party executing (or on whose behalf such signature is
executed) the same with the same force and effect as if such facsimile signature
page were an original thereof.

                  4.11 Severability. In case any one or more of the provisions
of this Agreement shall be invalid or unenforceable in any respect, the validity
and enforceability of the remaining terms and provisions of this Agreement shall
not in any way be affecting or impaired thereby and the parties will attempt to
agree upon a valid and enforceable provision which shall be a reasonable
substitute therefor, and upon so agreeing, shall incorporate such substitute
provision in this Agreement.

                  4.12 Remedies. In addition to being entitled to exercise all
rights provided herein or granted by law, including recovery of damages, the
Purchasers will be entitled to specific performance of the obligations of the
Company under the Transaction Documents. Each of the Company and the Purchasers
agree that monetary damages may not be adequate compensation for any loss
incurred by reason of any breach of its obligations described in the foregoing
sentence and hereby agrees to waive in any action for specific performance of
any such obligation the defense that a remedy at law would be adequate.

                  4.13 Independent Nature of Purchasers' Obligations and Rights.
The obligations of each Purchaser under any Transaction Document is several and
not joint with the obligations of any other Purchaser, and no Purchaser shall be
responsible in any way for the performance of the obligations of any other
Purchaser under any Transaction Document. Nothing contained herein or in any
Transaction Document, and no action taken by any Purchaser pursuant thereto,
shall be deemed to constitute the Purchasers as a partnership, an association, a
joint venture or any other kind of entity, or create a presumption that the
Purchasers are in any way acting in concert with respect to such obligations or
the transactions contemplated by the Transaction Document. Each Purchaser shall
be entitled to independently protect and enforce its rights, including without
limitation the rights arising out of this Agreement or out of the Transaction
Documents, and it shall not be necessary for any other Purchaser to be joined as
an additional party in any proceeding for such purpose.


                                      -17-
   18
                   [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK
                             SIGNATURE PAGE FOLLOWS]


                                      -18-
   19
                  IN WITNESS WHEREOF, the parties hereto have caused this
Securities Purchase Agreement to be duly executed by their respective authorized
signatories as of the date first indicated above.

                           .                NEOTHERAPEUTICS, INC.



                                            By:  /s/ Samuel Gulko
                                               --------------------------------
                                                 Samuel Gulko
                                                 Chief Financial Officer
   20
                            MONTROSE INVESTMENTS LTD.



                            By: /s/ Kevin A. O'Neal
                                ---------------------------------
                                Name:   Kevin A. O'Neal
                                Title:  Authorized Signatory


                                                                          
                            Purchase Price for Common Stock
                            to be acquired at Closing:                       $     8.26

                            Number of Shares to be acquired at
                            Closing:
                                                                                484,262

                            Warrant Shares subject to Closing
                            Warrant:                                             96,853



                            Address for Notice:

                            Montrose Investments Ltd.
                            300 Crescent Court, Suite 700
                            Dallas, TX 75201
                            Facsimile: (214) 758-1221
                            Attn: John Mosle and Kim Rozman


                            With copies to:
                            Robinson Silverman Pearce Aronsohn & Berman LLP
                            1290 Avenue of the Americas
                            New York, NY 10104
                            Facsimile No.:  (212) 541-4630 and (212) 541-1432
                            Attn:  Kenneth L. Henderson, Esq.
                                   Eric L. Cohen, Esq.
   21
                            STRONG RIVER INVESTMENTS, INC.



                            By:   /s/ Kenneth L. Henderson
                                  ------------------------------------
                                  Name:   Kenneth L. Henderson
                                  Title:  Attorney-in-fact


                                                                                
                                  Purchase Price for Common Stock
                                  to be acquired at Closing:                       $     8.26

                                  Number of Shares to be acquired at
                                  Closing:
                                                                                      484,262

                                  Warrant Shares subject to Closing
                                  Warrant:                                             96,853


                             Address for Notice:

                             Strong River Investment, Inc.
                             c/o Gonzalez-Ruiz & Aleman (BVI) Limited
                             Wickhams Cay I, Vanterpool Plaza
                             P.O. Box 873
                             Road Town, Tortola. BVI


                             With copies to:

                             Robinson Silverman Pearce Aronsohn & Berman LLP
                             1290 Avenue of the Americas
                             New York, NY 10104
                             Facsimile No.:  (212) 541-4630 and (212) 541-1432
                             Attn:  Kenneth L. Henderson, Esq.
                                    Eric L. Cohen, Esq.