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                                                                    Exhibit 10.6

                        CONFIDENTIAL SEPARATION AGREEMENT
                               AND GENERAL RELEASE

          THIS CONFIDENTIAL SEPARATION AGREEMENT AND GENERAL RELEASE (this
"Agreement") is entered into as of November 13, 2003 (the "Effective Date"), by
and between Spectrum Pharmaceuticals, Inc., a Delaware corporation (the
"Company") and John L. McManus, an individual ("Executive").

                                    RECITALS

          WHEREAS, Executive is presently employed by the Company;

          WHEREAS, Executive and the Company (collectively, the "Parties") have
agreed that Executive will resign from his positions as an officer and an
employee of the Company;

          WHEREAS, the Parties wish to specify the terms of the resignation and
resolve any outstanding issues between them.

                                    AGREEMENT

          NOW THEREFORE, in consideration of the representations and agreements
contained herein, and of other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, and intending to be bound hereby,
the Company and Executive hereby agree to terminate their employment
relationship on the following basis:

     1. Resignation. Executive hereby resigns any and all positions with the
Company, including, without limitation, as Vice President, Finance and Strategic
Planning and Assistant Corporate Secretary and an employee of the Company as of
the Effective Date. Executive understands and agrees that he is giving up any
right or claim to future employment with the Company and any compensation or
benefit of such employment, including any compensation and/or benefits owed to
the Executive as of the Effective Date, except for compensation and/or benefits
provided for in this Agreement. Executive acknowledges that he has received all
compensation and benefits due to him through the Effective Date.

     2. Compensation. In consideration for Executive's agreement to resign
pursuant to the terms of this Agreement:

          (a) In lieu of severance, concurrently with the execution of this
Agreement, Executive shall receive a bonus for the 2003 calendar year in the
amount of $20,500 less withholdings in accordance with applicable law. Also
concurrently with the execution of this Agreement, Executive shall receive a
lump-sum cash payment for accrued and unpaid vacation as well as accrued and
unpaid salary through the date of this Agreement, less applicable statutory
deductions. In addition, the Company shall pay to Employee, on or before January
5, 2004, but no earlier than January 1, 2004, $205,000 in cash, less applicable
statutory deductions.

          (b) The Parties acknowledge that the Investor Relations Consulting
Agreement by and between the Company and McManus & Company, Inc. ("M&C") dated

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August 19, 2002 (the "M&C Consulting Agreement") shall remain in full force and
effect until its expiration on July 31, 2004. Executive and Company agree to,
and Executive agrees to cause M&C to, continue to honor the terms of the M&C
Consulting Agreement through July 31, 2004; provided that the Company shall only
request that M&C provide reasonable and customary services under the M&C
Consulting Agreement; and, provided, further, that if Executive believes any
such requested services are unreasonable, Executive shall be entitled to contact
any member of the Company's board of directors to verify the validity of the
request. The Company shall remain obligated to pay M&C on the first business day
of each month, for the applicable month, the fees due under such M&C Consulting
Agreement through July 31, 2004. In addition to the foregoing, Executive agrees
to use his best efforts to assist with the completion and filing of the
Company's Quarterly Report on Form 10-Q for the quarter ended September 30, 2003
(the "10-Q"); however, no additional compensation shall be paid for Executive's
services in connection with the 10-Q.

          (c) The Company hereby covenants and agrees to submit the 90,000 share
conditional stock option grant made to Executive on September 12, 2003 (the
"Grant") to the Company's stockholders for approval at the Company's 2004 Annual
Meeting of Stockholders ("Annual Meeting") with a recommendation that the
stockholders approve such Grant. If the stockholders fail to approve the Grant
at the Annual Meeting, the Company shall pay Executive $504,900, less applicable
statutory withholdings and deductions, within seven (7) days after the Annual
Meeting.

          (d) Following the Effective Date, the Company shall continue to
provide Executive with medical, dental and vision benefits under the Company's
existing insurance plans, or in the alternative, at the Company's election, pay
one hundred-percent (100%) of the COBRA premium with respect to medical, dental
and vision benefits for Executive and his spouse and dependents until December
31, 2003, provided that Executive elects to continue benefits under COBRA and
remains eligible for COBRA throughout that period.

          (e) All stock options previously granted to Executive shall become
fully vested as of the Effective Date, subject only to any applicable
stockholder approval requirements, and Executive shall be entitled to exercise
such options in whole or in part from time to time during the one year period
commencing on November 17, 2003.

     3.   Options. Executive and the Company are parties to certain written
agreements pursuant to which Executive has been granted options to purchase
stock in the Company. Executive acknowledges that although such options might be
identified as incentive stock options, such options may not be qualified for
treatment as incentive stock options, either now or in the future. Executive is
advised to consult with his personal tax advisor to determine whether the
options are qualified for treatment as incentive stock options. Except as set
forth in Section 2(c), 2(e) and this Section 3, Executive's rights under his
existing option agreements are not intended to be modified by this Agreement in
any way.

     4.   Return of Company Property. Except as expressly provided for herein,
at the Company's request, the Executive will return to the Company all files,
records, credit cards, keys, equipment, and any other property of the Company or
documents maintained by him for the Company's use or benefit, on or before the
Effective Date.


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     5.   Confidentiality. The Parties acknowledge that this Agreement and all
matters relating to or leading up to the negotiation and effectuation of this
Agreement are confidential and shall not be disclosed to any third party except
as follows: the Company may disclose the terms of this Agreement to the public
as required by law, including without limitation, the Securities Act of 1933, as
amended, and the Securities Exchange Act of 1934, as amended; the Company may
disclose the terms of this Agreement to Company employees with a business
purpose for receiving such information; the Parties may disclose the terms of
the Agreement to their respective legal, accounting and tax advisors to the
extent necessary for them to perform services; and the Parties may disclose the
terms of this Agreement to the Internal Revenue Service and the California
Franchise Tax Board as required by law, rule or regulation, or as otherwise
required by law or necessary to enforce the terms of this Agreement. If any
disclosure is made as permitted by this paragraph other than to governmental
authorities as required by law, then such persons or entities shall be cautioned
about the confidentiality obligations imposed by this Agreement.

     6.   Non-Disclosure, Non-Competition and Non-Solicitation.

          (a) Executive agrees that he will not disclose at any time, other than
to an authorized employee, officer, director or agent of the Company, any
information relating to the Company's business, trade, practices, trade secrets
or know-how or proprietary information without the Company's prior express
written consent. Executive agrees that until the first anniversary of the
Effective Date, Executive shall not directly or indirectly solicit, induce,
recruit or encourage any of the Company's employees to leave their employment or
take away such employees to leave their employment or take away such employees
or attempts to solicit, induce, recruit, encourage or take away employees of the
Company.

     7.   General Release by Executive.

          (a) Release of Claims. Executive does hereby for himself and his
respective heirs, successors and assigns, release, acquit and forever discharge
the Company, its parents, subsidiaries and affiliates and any of their officers,
directors, managers, employees, representatives, related entities, successors
and assigns, and all persons acting by, through or in concert with them (the
"Company Releasees") of and from any and all claims, actions, charges,
complaints, causes of action, rights, demands, debts, damages, or accountings of
whatever nature, known or unknown which Executive may have against the Company
Releasees, or any of them, based on any actions or events which occurred prior
to the Effective Date, including, but not limited to, those related to, or
arising from, Executive's employment with the Company or the termination
thereof, including, without limitation, any claims under Title VII of the Civil
Rights Act of 1964, the Americans with Disabilities Act and the California Fair
Employment and Housing Act (collectively, the "Claims" or individually,
"Claim"), but excluding any claims arising under the Company's agreements with
McManus & Company, Inc. and any claims for defense and indemnity under the
Company's Certificate of Incorporation and Bylaws.


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          (b) Release of Unknown Claims. In addition, Executive expressly waives
all rights under Section 1542 of the Civil Code of the State of California,
which reads as follows:

               A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH A CREDITOR DOES
               NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF
               EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY
               AFFECTED HIS SETTLEMENT WITH THE DEBTOR.

          (c) No Assignment of Claims. Executive represents and warrants to the
Company Releasees that there has been no assignment or other transfer of any
interest in any Claim which Executive may have against the Company Releasees, or
any of them, and Executive agrees to indemnify and hold the Company Releasees
harmless from any liability, claims, demands, damages, costs, expenses and
attorneys' fees incurred as a result of any person asserting any such assignment
or transfer of any rights or Claims if Executive has made such assignment or
transfer from such party.

          (d) No Suits or Actions. Executive represents and warrants to the
Company that there have been no claims, suits, actions, complaints, or charges
filed by him against the Company Releasees, or any of them. Executive agrees
that if he hereafter commences, joins in, or in any manner seeks relief through
any suit arising out of, based upon, or relating to any of the Claims released
hereunder, or in any manner asserts against the Company Releasees, or any of
them, any of the Claims released hereunder, then he will pay to the Company
Releasees against whom such claim(s) is asserted, in addition to any other
damages caused thereby, all attorneys' fees incurred by such Company Releasees
in defending or otherwise responding to said suit or Claim.

          (e) No Admission. Executive further understands and agrees that
neither the payment of money nor the execution of this Release shall constitute
or be construed as an admission of any liability whatsoever by the Company
Releasees.

     8.   General Release by the Company.

          (a) Release of Claims. The Company does hereby for itself and its
respective successors and assigns, release, acquit and forever discharge
Executive and his heirs, estates, successors and assigns, and all persons acting
by, through or in concert with them (the "Executive Releasees") of and from any
and all claims, actions, charges, complaints, causes of action, rights, demands,
debts, damages, or accountings of whatever nature, known or unknown which the
Company may have against the Executive Releasees, or any of them, based on any
actions or events which occurred prior to the Effective Date, including, but not
limited to, those related to, or arising from, Executive's employment with the
Company or the termination thereof (collectively, the "Claims" or individually,
"Claim"), but excluding any claims arising under the Company's agreements with
McManus & Company, Inc.

          (b) Release of Unknown Claims. In addition, the Company expressly
waives all rights under Section 1542 of the Civil Code of the State of
California, which reads as follows:

               A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH A CREDITOR DOES
               NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF
               EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE MATERIALLY
               AFFECTED HIS SETTLEMENT WITH THE DEBTOR.


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          (c) No Assignment of Claims. The Company represents and warrants to
the Executive Releasees that there has been no assignment or other transfer of
any interest in any Claim which the Company may have against the Executive
Releasees, or any of them, and the Company agrees to indemnify and hold the
Executive Releasees harmless from any liability, claims, demands, damages,
costs, expenses and attorneys' fees incurred as a result of any person asserting
any such assignment or transfer of any rights or Claims if the Company has made
such assignment or transfer from such party.

          (d) No Suits or Actions. The Company agrees that if it hereafter
commences, joins in, or in any manner seeks relief through any suit arising out
of, based upon, or relating to any of the Claims released hereunder, or in any
manner asserts against the Executive Releasees, or any of them, any of the
Claims released hereunder, then it will pay to the Executive Releasees against
whom such claim(s) is asserted, in addition to any other damages caused thereby,
all attorneys' fees incurred by such Executive Releasees in defending or
otherwise responding to said suit or Claim.

          (e) No Admission. The Company further understands and agrees that
neither the payment of money nor the execution of this Release shall constitute
or be construed as an admission of any liability whatsoever by the Executive
Releasees.

     9. Nondisparagement. The Company and Executive agree not to make any
disparaging or derogatory comments, public or otherwise, concerning each other,
or M&C or McManus Financial Consultants, Inc. ("MFC"), and Executive shall
refrain and shall cause M&C and MFC to refrain from making any disparaging
comments, public or otherwise, concerning any employees, officers or directors
of the Company. The Company's obligation under this provision shall be limited
to (i) causing its officers and directors and (ii) using its best efforts to
cause other employees, to refrain from making any disparaging or derogatory
comments, public or otherwise, concerning Executive, M&C and MFC. The Company
will advise its officers, directors and employees in writing of the existence of
this nondisparagement obligation. In addition, the Company shall provide
Executive a reasonable opportunity to review and comment in advance on any press
release or filing with the Securities and Exchange Commission regarding
Executive's employment or separation from the Company, and M&C and MFC's
consulting relationship with the Company, and the Company shall not unreasonably
disregard any such comments provided by Executive.

     10. Successors and Assigns. This Agreement shall be binding upon and inure
to the benefit of and be enforceable by the parties hereto and their respective
successors and assigns. Notwithstanding the foregoing, neither this Agreement
nor any rights hereunder may be assigned to any party by the Company or
Executive without the prior written consent of the other party hereto.

     11. Entire Agreement/No Oral Modification. This Agreement contains all of
the terms, promises, representations, and understandings, oral or written, made
between the Company and Executive with respect to the subject matter hereof and
supersedes all prior representations, understandings, or agreements, oral or
written, between the Company and


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Executive, with respect to such matters, which the Parties acknowledge have been
merged into this Agreement. This Agreement may not be modified other than with a
writing executed by both parties and stating an intent to modify this agreement.

     12.  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 (a) the date of transmission, if
such notice or communication is delivered via facsimile at the facsimile number
specified in this Section prior to 5:00 p.m. (Pacific Standard Time) on a
business day, (b) the next business day after the date of transmission, if such
notice or communication is delivered via facsimile at the facsimile number
specified in this Section on a day that is not a business day or later than 5:00
p.m. (Pacific Standard Time) on any business day, or (c) the business day
following the date of mailing, if sent by U.S. nationally recognized overnight
courier service such as Federal Express. The address for such notices and
communications shall be as follows:

          If to the Company:

          Spectrum Pharmaceuticals, Inc.
          157 Technology Drive
          Irvine, CA 92618
          Attn:  CEO
          Fax No.:  (949) 788-6706

          If to the Executive:

          John McManus
          23811 Inverness Place
          Laguna Niguel, CA 92677
          Fax No.:  (949) 481-9829

          Unless otherwise stated above, such communications shall be effective
when they are received by the addressee thereof in conformity with this Section.
Any party may change its address for such communications by giving notice
thereof to the other parties in conformity with this Section.

     13.  Governing Law and Forum Selection. This Agreement shall be governed by
the laws of the State of California, without regard for conflict of law
principles. Any actions arising out of relating to this Agreement shall be filed
in either the Superior Court of the State of California for the County of
Orange, or the United States District Court for the Central District of
California, Southern Division, located in the County of Orange.

     14.  Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, but all of which shall
constitute the same instrument.


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          IN WITNESS WHEREOF, this Agreement is executed by the parties set
forth below as of the date first indicated above.

THE COMPANY                                   EXECUTIVE

SPECTRUM PHARMACEUTICALS, INC.                JOHN MCMANUS,
a Delaware corporation                        an individual



By:  /s/ Rajesh C. Shrotriya                   /s/ John McManus
    ----------------------------------        ----------------------------------


Title:  Chairman, CEO & President
       -------------------------------



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