UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                  SCHEDULE 13D
                   Under the Securities Exchange Act of 1934
                                (Amendment No. 5)*


                         SPECTRUM PHARMACEUTICALS, INC.
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                                (Name of Issuer)

                    Common Stock, par value $0.001 per share
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                         (Title of Class of Securities)

                                   84763A108
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                                 (CUSIP Number)

Mitchell D. Kaye, Manager                            with a copy to:
Xmark Asset Management, LLC                          Steven E. Siesser, Esq.
301 Tresser Boulevard                                Lowenstein Sandler PC
Suite 1320                                           65 Livingston Avenue
Stamford, CT 06901                                   Roseland, New Jersey  07068
(203) 653-2500                                       (973) 597-2506
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                 (Name, Address and Telephone Number of Person
                Authorized to Receive Notices and Communications)

                                  July 15, 2005
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             (Date of Event which Requires Filing of this Statement)


If the filing person has previously  filed a statement on Schedule l3G to report
the  acquisition  that is the subject of this  Schedule  13D, and is filing this
schedule  because of Sections 240.13d-1(e),  240.13d-1(f) or 240.13d-1(g), check
the following box. [ ]

Note:  Schedules  filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits.  See Section 240.13d-7 for other
parties to whom copies are to be sent.

* The remainder of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for  any  subsequent   amendment   containing   information  which  would  alter
disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
Notes).




Cusip No.         84763A108
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1.  Names of Reporting Persons.  I.R.S. Identification Nos. of above persons
   (entities only):
                       Xmark Asset Management, LLC
                               13-3954392
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2.  Check the Appropriate Box if a Member of a Group (See Instructions):
         (a)                  Not
         (b)               Applicable
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3.  SEC Use Only
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4.  Source of Funds (See Instructions):  WC
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5.  Check  if  Disclosure of  Legal Proceedings  Is Required  Pursuant  to Items
    2(d) or 2(e):                 Not Applicable
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6.  Citizenship or Place of Organization:   New York, United States

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    Number of                      7. Sole Voting Power:                  *
                                     -------------------------------------------
    Shares Beneficially            8. Shared Voting Power:                *
                                     -------------------------------------------
    Owned by
    Each Reporting                 9. Sole Dispositive Power:             *
                                      ------------------------------------------
    Person With                    10. Shared Dispositive Power:          *
                                      ------------------------------------------
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11. Aggregate Amount Beneficially Owned by Each Reporting Person:   769,267*
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12. Check if  the  Aggregate  Amount in  Row (11) Excludes  Certain  Shares (See
    Instructions):
                                X
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13. Percent of Class Represented by Amount in Row (11):   4.99%*
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14. Type of Reporting Person (See Instructions):   IA
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*   The reporting  person is Xmark  Asset  Management,  LLC ("XAM"),  a New York
limited liability company.  XAM's interest in the securities  reported herein is
limited to its  pecuniary  interest,  if any,  in Xmark Fund,  L.P.,  a Delaware
limited  partnership  ("Xmark  LP"),  and Xmark  Fund,  Ltd.,  a Cayman  Islands
exempted company ("Xmark Ltd").

Xmark LP is the holder of: (i) 343,040  shares (the "Xmark LP Shares") of Common
Stock,   par  value  $0.001  per  share  (the  "Common   Stock"),   of  Spectrum
Pharmaceuticals,  Inc., a Delaware  corporation (the  "Company");  (ii) warrants
(the "2003 Xmark LP Warrants") which,  subject to certain exercise  restrictions
contained  therein,  entitle  Xmark LP to purchase an aggregate of up to 168,000
shares of Common Stock at an exercise  price of $6.50 per share,  which exercise
price is subject to adjustment as set forth in the 2003 Xmark LP Warrants; (iii)
warrants  (the "2004  Xmark LP  Warrants")  which,  subject to certain  exercise
restrictions contained therein,  entitle Xmark LP to purchase an aggregate of up
to 53,666 shares of Common Stock at an exercise price of $10.00 per share, which
exercise  price is  subject  to  adjustment  as set  forth in the 2004  Xmark LP
Warrants;  and (iv) 108 call options  exercisable  into 10,800  shares of Common
Stock at an exercise price of $10.00 per share.

Xmark Ltd is the holder of: (i) 343,037  shares of Common  Stock (the "Xmark Ltd
Shares," and together  with the Xmark LP Shares,  the  "Shares");  (ii) warrants





(the "2003 Xmark Ltd  Warrants,"  and together  with the 2003 Xmark LP Warrants,
the "2003 Warrants") which, subject to certain exercise  restrictions  contained
therein,  entitle Xmark Ltd to purchase an aggregate of up to 252,000  shares of
Common Stock at an exercise  price of $6.50 per share,  which  exercise price is
subject  to  adjustment  as set  forth in the 2003  Xmark  Ltd  Warrants;  (iii)
warrants  (the "2004 Xmark Ltd  Warrants,"  and together  with the 2004 Xmark LP
Warrants,  the "2004 Warrants") which, subject to certain exercise  restrictions
contained  therein,  entitle  Xmark Ltd to purchase an aggregate of up to 51,335
shares of Common Stock at an exercise price of $10.00 per share,  which exercise
price is subject to adjustment as set forth in the 2004 Xmark Ltd Warrants;  and
(iv) 107 call  options  exercisable  into  10,700  shares of Common  Stock at an
exercise price of $10.00 per share.

The 2003 Warrants and the 2004 Warrants each provide that in no event shall such
warrants  be  exercisable  for  shares of Common  Stock to the  extent  that the
issuance of Common Stock thereunder  would result in the "beneficial  ownership"
(as defined in Section 13(d) of the Securities Exchange Act of 1934, as amended,
and Regulations  13D-G  thereunder) by Xmark LP, Xmark Ltd, or their affiliates,
of more than 4.95% and 4.99%,  respectively,  of the Common Stock (the "Issuance
Limitation"). The Issuance Limitation may not be waived.

XAM serves as  investment  manager  for each of Xmark LP and Xmark Ltd.  In such
capacity,  XAM  possesses  the power to vote and direct the  disposition  of all
securities  held by Xmark LP and Xmark Ltd.  Thus,  as of July 15,  2005 for the
purposes  of Reg.  Section  240.13d-3,  XAM may be  deemed to  beneficially  own
769,267  shares of Common Stock,  or 4.99% of the Common Stock deemed issued and
outstanding as of that date.






Item 5.   Interest in Securities of the Issuer.
          ------------------------------------

          Based upon the Company's  Prospectus filed with the Commission on June
24, 2005, there were 15,352,949 shares of Common Stock issued and outstanding as
of May 19, 2005.

          As of July 15, 2005,  Xmark LP is the holder of (i) 343,040  shares of
Common Stock of the Company,  (ii) warrants which,  subject to certain  exercise
restrictions contained therein,  entitle Xmark LP to purchase up to an aggregate
of 168,000  shares of Common Stock at an exercise  price of $6.50 per share (the
"2003 Xmark LP Warrants"),  which exercise price is subject to adjustment as set
forth in the 2003 Xmark LP Warrants,  (iii) warrants  which,  subject to certain
exercise restrictions  contained therein,  entitle Xmark LP to purchase up to an
aggregate of 53,666  shares of Common  Stock at an exercise  price of $10.00 per
share  (the  "2004  Xmark LP  Warrants"),  which  exercise  price is  subject to
adjustment as set forth in the 2004 Xmark LP Warrants, and (iv) 108 call options
exercisable  into 10,800  shares of Common Stock at an exercise  price of $10.00
per share.  Xmark Ltd is the holder of (i) 343,037 shares of Common Stock,  (ii)
warrants which,  subject to certain  exercise  restrictions  contained  therein,
entitle  Xmark Ltd to purchase up to an  aggregate  of 252,000  shares of Common
Stock at an exercise  price of $6.50 per share (the "2003  Xmark Ltd  Warrants,"
and  together  with the 2003  Xmark LP  Warrants,  the "2003  Warrants"),  which
exercise  price is  subject  to  adjustment  as set forth in the 2003  Xmark Ltd
Warrants,  (iii)  warrants  which,  subject  to  certain  exercise  restrictions
contained  therein,  entitle  Xmark Ltd to purchase up to an aggregate of 51,335
shares of Common Stock at an exercise price of $10.00 per share (the "2004 Xmark
Ltd  Warrants",  and  together  with  the  2004  Xmark LP  Warrants,  the  "2004
Warrants"),  which  exercise  price is subject to adjustment as set forth in the
2004 Xmark Ltd  Warrants,  and (iv) 107 call  options  exercisable  into  10,700
shares of Common Stock at an exercise price of $10.00 per share.

          The 2003  Warrants and the 2004 Warrants each provide that in no event
shall such warrants be exercisable for shares of Common Stock to the extent that
the  issuance  of  Common  Stock  thereunder  would  result  in the  "beneficial
ownership" (as defined in Section 13(d) of the Securities  Exchange Act of 1934,
as amended,  and Regulations  13D-G thereunder) by Xmark LP, Xmark Ltd, or their
affiliates, of more than 4.95% and 4.99%, respectively, of the Common Stock (the
"Issuance  Limitation").  The Issuance Limitation may not be waived. Thus, as of
July 15, 2005, for the purposes of Reg. Section 240.13d-3,  XAM may be deemed to
beneficially  own 769,267  shares of Common Stock,  or 4.99% of the Common Stock
deemed issued and outstanding as of that date.

          On July 15, 2005, XAM ceased to be the  beneficial  owner of more than
five percent of the Common Stock of the Company.

          The following table details the transactions effected since the filing
of Amendment No. 4 to the Schedule 13D, in Common Stock, by XAM or any person or
entity  controlled by XAM or any person or entity for which XAM possesses voting





or investment control over the securities thereof (each of which was effected in
an ordinary brokerage transaction):


                                   I. Xmark LP
                                   -----------

                                     (Sales)

    Date                             Amount                     Price
    ----                             ------                     -----

   6/13/05                            6,932                     $5.00
   6/14/05                            2,000                     $5.00
   6/14/05                           40,000                     $5.10
   6/15/05                            6,500                     $5.05
   6/15/05                            5,650                     $5.02
   6/15/05                           21,100                     $5.00
   6/17/05                            2,500                     $4.98
   6/21/05                           15,550                     $4.89
   6/22/05                            1,000                     $4.82
   6/23/05                            3,500                     $4.61
   7/12/05                            4,200                     $4.48
   7/13/05                            7,900                     $4.45
   7/14/05                           21,050                     $4.42
   7/14/05                           35,000                     $4.40
   7/15/05                           30,000                     $4.44
   7/15/05                           20,000                     $4.50


                                  II.  Xmark Ltd
                                  --------------

                                     (Sales)

    Date                             Amount                     Price
    ----                             ------                     -----

   6/13/05                            6,933                     $5.00
   6/14/05                            2,000                     $5.00
   6/14/05                           40,000                     $5.10
   6/15/05                            6,500                     $5.05
   6/15/05                            5,650                     $5.02
   6/15/05                           21,100                     $5.00
   6/17/05                            2,500                     $4.98
   6/21/05                           15,550                     $4.89
   6/22/05                            1,000                     $4.82
   6/23/05                            3,500                     $4.61
   7/12/05                            4,200                     $4.48
   7/13/05                            7,900                     $4.45
   7/14/05                           21,050                     $4.42
   7/14/05                           35,000                     $4.40
   7/15/05                           30,000                     $4.44
   7/15/05                           20,000                     $4.50





                                    Signature
                                    ---------

          After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information  set forth in this statement is true,  complete and
correct.


                                            July 19, 2005

                                            XMARK ASSET MANAGEMENT, LLC

                                            /s/ Mitchell D. Kaye
                                            ------------------------------------
                                            Mitchell D. Kaye, Manager


Attention:  Intentional  misstatements  or omissions of fact constitute  Federal
criminal violations (See 18 U.S.C. 1001).