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                                                                    EXHIBIT 10.1



                            STOCK PURCHASE AGREEMENT

     This Stock Purchase Agreement (this "Agreement") is made as of August 14,
2001, by and between Summit Capital Management LLC (the "Purchaser") and
NeoTherapeutics, Inc., a Delaware corporation (the "Company"), whereby the
parties agree as follows:

     The Purchaser shall buy from the Company and the Company agrees to sell to
the Purchaser 600,000 shares (the "Shares") of the Company's common stock, par
value $.001 per share (the "Common Stock") having an aggregate purchase price of
$2,010,000, at a price per share of $3.35.

     The Company is a corporation duly incorporated and validly existing under
the laws of the State of Delaware. The Company has the requisite corporate power
and authority to enter into and perform its obligations under this Agreement and
to issue and sell the Shares in accordance with the terms of this Agreement, and
the issuance of the Shares shall not contravene any agreement to which the
Company is a party. The Shares have been duly authorized by all necessary
corporate action, and, when paid for and issued in accordance with the terms of
this Agreement, the Shares will be validly issued, fully paid and nonassessable.
The Shares have been listed on the Nasdaq National Market.

     The Shares are being issued and sold pursuant to a registration statement
on Form S-3, File No. 333-53108, which registration statement has been declared
effective and continues to be effective and not subject to any stop order by the
Securities and Exchange Commission. The Company has delivered to the Purchaser
and the Purchaser has reviewed a copy of the prospectus included in such
registration statement and a prospectus supplement regarding the issuance and
sale of the Shares, a copy of which is attached hereto as Exhibit A.

     Prior to the close of business on August 14, 2001:

     1.   The Purchaser shall wire the purchase price set forth above to the
          Company to the account set forth below:

              Chase Manhattan Bank, N.Y.C.
              4 New York Plaza, 15th Floor
              New York, NY  10004

              ABA Routing No:  021 000 021
              FBO:  Salomon Smith Barney, Inc.
                    Account No.  066-198038
              For further credit to:  NeoTherapeutics, Inc.
                    Account No. 561-04051-19-103

     2.   The Company shall cause its transfer agent to transmit the Shares
          electronically to the Purchaser's account with the DTC set forth
          below:

              DTC No. 0773
              Account No. 118-11273-23
              Summit Capital Management LLC

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          Notices to the Company shall be delivered to:

          NeoTherapeutics, Inc.
          Attention: Samuel Gulko, Senior Vice President, Finance
          157 Technology Drive,
          Irvine, California  92618
          Facsimile:  (949) 788-6706

          Notices to the Purchaser shall be delivered to:

          Summit Capital Management LLC
          Attn:  David W. Simpson
          2 Union Square, Suite 3900
          601 Union St.
          Seattle, Washington  98101
          Facsimile: (206) 447-6204

     Delivery of an executed copy of a signature page to this Agreement by
facsimile transmission shall be effective as delivery of a manually executed
copy of this Agreement and shall be effective and enforceable as the original.
This Agreement shall be governed and construed in accordance with the internal
laws of the State of California without giving effect to the conflicts of law
principles thereunder.


                           [SIGNATURE PAGE TO FOLLOW]


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AGREED AND ACCEPTED, as of the date indicated above:

NeoTherapeutics, Inc.


By: /s/ Samuel Gulko
    -------------------------------
         Name: Samuel Gulko
         Title: Senior Vice President, Finance

Summit Capital Management LLC


By: /s/ David W. Simpson
    -------------------------------
         Name: David W. Simpson
         Title: Chief Investment Officer



               [SIGNATURE PAGE TO SECURITIES PURCHASE AGREEMENT]


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