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                                                                   EXHIBIT 10.33

                         SCICLONE PHARMACEUTICALS, INC.
                          CHANGE IN CONTROL AGREEMENT

        This Change in Control Agreement (the "Agreement") is effective as of
November 19, 1999, by and between Donald R. Sellers (the "Employee") and
SciClone Pharmaceuticals, Inc., a California corporation (the "Company").

                                    RECITALS

        A. The Employee presently serves as Chief Executive Officer and
President of the Company and performs significant strategic and management
responsibilities necessary to the continued conduct of the Company's business
and operations.

        B. The Board of Directors of the Company (the "Board") has determined
that it is in the best interests of the Company and its shareholders to assure
that the Company will have the continued dedication and objectivity of the
Employee, notwithstanding the possibility or occurrence of a Change in Control
(as defined below) of the Company.

        C. The Board believes that it is imperative to provide the Employee with
certain severance benefits upon the Employee's termination of employment
following a Change in Control that will provide the Employee with enhanced
financial security and provide sufficient incentive and encouragement to the
Employee to remain with the Company following a Change in Control.

                                    AGREEMENT

        The Employee and the Company agree as set forth below:

        1. Terms of Employment. If the Employee's employment with the Company
terminates for any reason following a Change in Control, but on or before the
first anniversary of the Change in Control, the Employee shall not be entitled
to any payments, benefits, damages, awards or compensation other than as
provided by this Agreement. During his or her employment with the Company, the
Employee agrees to devote his or her full business time, energy and skill to his
or her duties with the Company. These duties shall include, but not be limited
to, any duties consistent with the Employee's position that may be assigned to
the Employee from time to time by the Company or the Board.

        2. Severance Benefits Upon Termination following a Change in Control.
Subject to the limitations set forth in Sections 3 and 4 below, if the
Employee's employment with the Company terminates following a Change in Control
but on or before the first anniversary of such Change in Control, then the
Employee shall be entitled to receive, in addition to the compensation and
benefits earned by the Employee through the date of his or her termination,
severance benefits as follows:


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               (a) Involuntary Termination. If the Employee's employment with
the Company is terminated as a result of Involuntary Termination, then the
Employee shall be entitled to receive the following severance benefits:

                      (i) The Employee shall be entitled to receive severance
pay in an amount equal to one hundred percent (100%) of his annual base salary
as in effect at the time of such termination. Any severance to which the
Employee is entitled pursuant to this section shall be paid in a lump sum, less
applicable withholding, within thirty (30) days following the Employee's
termination.

                      (ii) With respect to any unvested options to purchase
shares of the stock of the Company held by the Employee, the Employee shall
immediately become vested in full in such options at the time of such
termination.

                      (iii) The Company shall, if permitted under the Company's
existing health insurance plans, continue the Employee's existing group health
insurance coverage. If not so permitted, the Company shall reimburse the
Employee for any COBRA premiums paid by the Employee for continued group health
insurance coverage. Such health insurance coverage or reimbursement of COBRA
premiums shall continue until the earlier of (1) twelve (12) months after the
date of the Employee's Involuntary Termination or (2) the date on which the
Employee commences New Employment.

               (b) Voluntary Resignation; Termination For Cause. If the
Employee's employment terminates by reason of the Employee's voluntary
resignation (but not as a result of an Involuntary Termination) or as a result
of the Employee's termination for Cause, then the Employee shall not be entitled
to receive any severance pay or benefits under this Agreement.

               (c) Disability; Death. If the Company terminates the Employee's
employment as a result of the Employee's Disability, or death, then the Employee
shall not be entitled to receive any severance pay or benefits under this
Agreement.

        3. Release of Claims; Resignation. The Employee's entitlement to any
severance pay or benefits under Section 2(a) is conditioned upon the Employee's
execution and delivery to the Company of (a) a general release of known and
unknown claims in the form attached hereto as Exhibit A and (b) a resignation
from all of the Employee's positions with the Company, including from the Board
of Directors and any committees thereof on which the Employee serves, in a form
satisfactory to the Company.

        4. Parachute Payments. In the event that any payment or benefit received
or to be received by the Employee pursuant to this Agreement or otherwise
(collectively, the "Payments") would result in a "parachute payment" as
described in section 280G of the Internal Revenue Code of 1986, as amended,
notwithstanding the other provisions of this Agreement, the amount of such
Payments will not exceed the amount which produces the greatest after-tax
benefit to the Employee. For purposes of the foregoing, the greatest after-tax
benefit will be determined within thirty (30) days of the occurrence of such
payment to the Employee, in the Employee's sole and absolute discretion. If no
such determination is made by the Employee

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within thirty (30) days of the occurrence of such payment, the Company will
promptly make such determination in a fair and equitable manner.

        5. Consulting Services. During the twenty-four (24) months following any
Involuntary Termination for which the Employee receives the severance pay and
benefits described in Section 2(a), the Employee shall be retained by the
Company as an independent contractor to provide consulting services to the
Company at its request for up to eight (8) hours per week. These services shall
include any reasonable requests for information or assistance by the Company,
including, but not limited to, the transition of the Employee's duties. Such
services shall be provided at mutually convenient times. For the actual
provision of such services, the Company shall pay to the Employee a consulting
fee of $2,000 per day, plus reasonable out-of-pocket expenses (for example,
travel and lodging).

        6. Definition of Terms. The following terms referred to in this
Agreement shall have the following meanings:

               (a) "Cause" shall mean any of the following:

                      (i) the Employee's theft, dishonesty, misconduct or
falsification of any records of the Company, its successor, or any subsidiary of
the Company or its successor (collectively, the "Company Group");

                      (ii) the Employee's misappropriation or improper
disclosure of confidential or proprietary information of the Company Group;

                      (iii) any intentional action by the Employee which has a
material detrimental effect on the reputation or business of the Company Group;

                      (iv) the Employee's failure or inability to perform any
reasonable assigned duties after written notice from the Company Group of, and a
reasonable opportunity to cure, such failure or inability;

                      (v) any material breach by the Employee of any employment
agreement between the Employee and the Company Group, which breach is not cured
pursuant to the terms of such agreement; or

                      (vi) the Employee's conviction of any criminal act which
impairs the Employee's ability to perform his or her duties for the Company
Group.

               (b) "Change in Control" shall mean: (i) a merger or other
transaction in which the Company or substantially all of its assets is sold or
merged and as a result of such transaction, the holders of the Company's common
stock prior to such transaction do not own or control a majority of the
outstanding shares of the successor corporation, (ii) the election of nominees
constituting a majority of the Board which nominees were not approved by a
majority of the Board prior to such election, or (iii) the acquisition by a
third party of twenty percent

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(20%) or more of the Company's outstanding shares which acquisition was without
the approval of a majority of the Board in office prior to such acquisition.

               (c) "Constructive Termination" shall mean any one or more of the
following:

                      (i) without the Employee's express written consent, the
assignment to the Employee, following the Change in Control, of any title or
duties, or any limitation of the Employee's responsibilities, that are
substantially inconsistent with the Employee's title(s), duties, or
responsibilities with the Company Group immediately prior to the date of the
Change in Control (including, but not limited to, Employee's failure to serve as
the Chief Executive Officer and/or failure to be a member of the executive
staff);

                      (ii) without the Employee's express written consent, the
relocation of the principal place of the Employee's employment, following the
Change in Control, to a location that is more than fifty (50) miles from the
Employee's principal place of employment immediately prior to the date of the
Change in Control, or the imposition of travel requirements substantially more
demanding of the Employee than such travel requirements existing immediately
prior to the date of the Change in Control;

                      (iii) any failure by the Company Group, following the
Change in Control, to pay, or any material reduction by the Company Group of,
(1) the Employee's base salary in effect immediately prior to the date of the
Change in Control, or (2) the Employee's bonus compensation, if any, in effect
immediately prior to the date of the Change in Control (subject to applicable
performance requirements with respect to the actual amount of bonus compensation
earned by the Employee), unless base salary and/or bonus reductions comparable
in amount and duration are concurrently made for a majority of the other
employees of the Company Group who have substantially similar titles and
responsibilities as the Employee; and

                      (iv) any failure by the Company Group, following the
Change in Control, to (1) continue to provide the Employee with the opportunity
to participate, on terms no less favorable than those in effect for the benefit
of any employee group which customarily includes a person holding the employment
position or a comparable position with the Company Group then held by the
Employee, in any benefit or compensation plans and programs, including, but not
limited to, the Company Group's life, disability, health, dental, medical,
savings, profit sharing, stock purchase and retirement plans, if any, in which
the Employee was participating immediately prior to the date of the Change in
Control, or in substantially similar plans or programs, or (2) provide the
Employee with all other fringe benefits (or substantially similar benefits),
including, but not limited to, relocation benefits, provided to any employee
group which customarily includes a person holding the employment position or a
comparable position with the Company Group then held by the Employee, which the
Employee was receiving immediately prior to the date of the Change in Control.

However, the foregoing conditions shall not constitute a Constructive
Termination unless the Employee has given written notice of any such
condition(s) to the Chairman of the Board and allowed the Company Group at least
twenty (20) days thereafter to correct such condition(s). If such condition(s)
are not corrected within that twenty (20) day period, the Employee may give

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written notice of his Constructive Termination to the Board, which shall be an
Involuntary Termination.

               (d) "Disability" means the inability of the Employee, in the
opinion of a qualified physician, to perform the essential functions of the
Employee's position with the Company Group, with or without reasonable
accommodation, because of the sickness or injury of the Employee.

               (e) "Involuntary Termination" shall mean the occurrence of either
of the following events after a Change in Control, but on or before the first
anniversary of such Change in Control:

                      (i) termination by Company Group of the Employee's
employment without Cause; or

                      (ii) the Employee's Constructive Termination.

"Involuntary Termination" shall not include any termination of the Employee's
employment that is (1) for Cause, (2) a result of the Employee's death or
Disability, or (3) a result of the Employee's voluntary resignation.

               (f) "New Employment" shall mean any employment obtained by the
Employee after the termination of the Employee's employment with the Company.

        7. Nonsolicitation. During his or her employment with the Company, and
for a period of one (1) year following the termination of his or her employment
for any reason, the Employee shall not directly or indirectly recruit, solicit,
or induce any person who on the date hereof is, or who subsequently becomes, an
employee, sales representative or consultant of the Company, to terminate his or
her relationship with the Company.

        8. Successors.

               (a) Company's Successors. Any successor to the Company or to all
or substantially all of the Company's business and/or assets shall be bound by
this Agreement in the same manner and to the same extent as the Company. For all
purposes under this Agreement, the term "Company" shall include any successor to
the Company's business and/or assets.

               (b) Employee's Successors. All rights of the Employee hereunder
shall inure to the benefit of, and be enforceable by, the Employee's personal or
legal representatives, executors, administrators, successors, heirs,
distributees, devisees and legatees. The Employee shall have no right to assign
any of his obligations or duties under this Agreement to any other person or
entity.

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        9. Notice.

               (a) General. Notices and all other communications contemplated by
this Agreement shall be in writing and shall be deemed to have been duly given
when personally delivered or when mailed by U.S. registered or certified mail,
return receipt requested and postage prepaid. In the case of the Employee,
mailed notices shall be addressed to the Employee at the home address which he
most recently communicated to the Company in writing. In the case of the
Company, mailed notices shall be addressed to its corporate headquarters, and
all notices shall be directed to the attention of its Secretary.

               (b) Notice of Termination. Any termination by the Company Group
or the Employee of their employment relationship shall be communicated by a
written notice of termination to the other party.

        10. Miscellaneous Provisions.

               (a) No Duty to Mitigate. The Employee shall not be required to
mitigate the amount of any payment contemplated by this Agreement (whether by
seeking New Employment or in any other manner), nor shall any such payment be
reduced by any earnings that the Employee may receive from any other source.

               (b) Waiver. No provision of this Agreement shall be modified,
waived or discharged unless the modification, waiver or discharge is agreed to
in writing and signed by the Employee and by an authorized officer of the
Company (other than the Employee). No waiver by either party of any breach of,
or of compliance with, any condition or provision of this Agreement by the other
party shall be considered a waiver of any other condition or provision or of the
same condition or provision at another time.

               (c) Choice of Law. The validity, interpretation, construction and
performance of this Agreement shall be governed by the laws of the State of
California.

               (d) Severability. The invalidity or unenforceability of any
provision or provisions of this Agreement shall not affect the validity or
enforceability of any other provision hereof, which shall remain in full force
and effect.

               (e) Arbitration. In the event of any dispute or claim relating to
or arising out of the Employee's employment relationship with the Company, this
Agreement, or the termination of the Employee's employment with the Company for
any reason (including, but not limited to, any claims of breach of contract,
wrongful termination, fraud or age, race, sex, national origin, disability or
other discrimination or harassment), the Employee and the Company agree that all
such disputes shall be fully, finally and exclusively resolved by binding
arbitration conducted by the American Arbitration Association in San Mateo
County, California. Judgment upon any decision or award rendered by the
arbitrator may be entered in any court having jurisdiction over the matter. The
Employee and the Company knowingly and willingly waive their respective rights
to have any such disputes or claims tried to a judge or jury.



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               (f) Prior Agreements. This Agreement supercedes all prior
understandings and agreements, whether written or oral, regarding the subject
matter of this Agreement, notwithstanding the foregoing, this Agreement does not
revise, amend or otherwise supercede that certain Employment Agreement by and
between the Company and Donald R. Sellers, dated as of February 1, 1996.

        IN WITNESS WHEREOF, each of the parties has executed this Agreement, in
the case of the Company by its duly authorized officer, as of the day and year
first above written.


                                             SCICLONE PHARMACEUTICALS, INC.



                                             By:
                                                ---------------------------



                                             EMPLOYEE


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

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                                    EXHIBIT A

                                     RELEASE



        In exchange for the severance pay and benefits described in the Change
in Control Agreement between SciClone Pharmaceuticals, Inc. (the "Company") and
me of November ___, 1999, I hereby release the Company, its parents and
subsidiaries, and their officers, directors, employees, attorneys, shareholders,
successors, assigns and affiliates, of and from any and all claims, liabilities,
and causes of action of every kind and nature, whether known or unknown, based
upon or arising out of any agreements, events, acts, omissions or conduct at any
time prior to and including the execution date of this Release, including, but
not limited to: all claims concerning my employment with the Company or the
termination of that employment; all claims pursuant to any federal, state or
local law, statute, or cause of action, including, but not limited to, the
federal Civil Rights Act of 1964, as amended; the federal Americans with
Disabilities Act of 1990; the federal Age Discrimination in Employment Act of
1967, as amended ("ADEA"); the California Fair Employment and Housing Act, as
amended; tort law; contract law; wrongful discharge; race, sex, age or other
discrimination or harassment; fraud; defamation; emotional distress; and breach
of the implied covenant of good faith and fair dealing.

        I am knowingly, willingly and voluntarily releasing any claims I may
have under the ADEA. I acknowledge that the consideration given for the release
in the preceding paragraph hereof is in addition to anything of value to which I
was already entitled. I further acknowledge that I have been advised by this
writing, as required by the ADEA, that: (a) this Release does not apply to any
rights or claims that may arise after I sign it; (b) I have the right to consult
with an attorney prior to signing this Release; (c) I have twenty-one (21) days
to consider this Release (although I may choose to voluntarily sign this Release
earlier); (d) I have seven (7) days after I sign this Release to revoke it; and
(e) this Release shall not be effective until the eighth day after it is signed
by me.

        In giving this release, which includes claims that may be unknown to me
at present, I acknowledge that I have read and understand Section 1542 of the
California Civil Code which reads as follows: "A GENERAL RELEASE DOES NOT EXTEND
TO CLAIMS WHICH THE 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." I hereby waive and relinquish all
rights and benefits under that section and any law of any jurisdiction of
similar effect with respect to my release of any unknown claims I may have, and
I affirm that it is my intention to release all known and unknown claims that I
have or may have against the parties released above.


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        This Release contains the entire agreement between the Company and me
regarding the subjects above, and it cannot be modified except by a document
signed by me and an authorized representative of the Company.



                                                EMPLOYEE


Date:
     ---------------------------                -------------------------------




                                                SCICLONE PHARMACEUTICALS, INC.


Date:                                           By:
     ---------------------------                   ----------------------------

                                                Its:
                                                    ---------------------------


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