PROMISSORY NOTE SECURED BY DEED OF TRUST


$1,000,000                                        San Mateo, California
                                                  August 1, 1996


     In  installments  as stated in this  Note,  for value  received,  Donald R.
Sellers and Jolice K. Sellers, husband and wife (together,  "Borrowers"), hereby
promise to pay to  SciClone  Pharmaceuticals,  Inc.,  a  California  corporation
("Lender") or order, at its offices at 901 Mariners Island Boulevard, San Mateo,
California,  or at such other place as Lender may from time to time designate in
writing, the principal sum of one Million Dollars ($1,000,000), with interest on
the  unpaid  balance of  principal  from the date of this Note until paid at the
rate of eight  percent  (8.00%) per annum (the "Note  Rate"),  on the  following
terms:

     I.  Payment:  The principal and interest due pursuant to this Note shall be
paid as follows:

                A. On  September  1, 1996 and on the first day of each  calendar
month  thereafter,  Borrowers shall pay to Lender equal monthly  payments in the
amount  of  Seven  Thousand  Three  Hundred  Thirty  Seven  and  65/100  Dollars
($7,337.65).

                B. The entire  principal  balance  with all then unpaid  accrued
interest  shall be due and payable on or before July 31,  2001,  unless the term
hereof is renewed as set forth herein. At the election of the Lender, the Lender
may extend the term of this Note, which extension shall be deemed effective upon
written notice from Lender to Borrowers delivered at any time before the initial
maturity  date  hereof,  which notice  shall state the  extended  maturity  date
selected by Lender. As of the effective date of such notice,  this Note shall be
extended on all the same terms and  conditions as are set forth  herein,  except
for the extended maturity date.

                C.  Principal  and interest  shall be payable in lawful money of
the United  States.  Interest shall be calculated on the basis of a 360-day year
consisting  of 12 thirty day  months.  Each  payment  shall be applied  first to
interest  then due and the balance of said  installment  shall be applied to the
principal sum.

                D.  This Note may be prepaid at any time, without penalty.

     II. Security: This Note is secured by a deed of trust of even date herewith
made by Borrowers,  as trustor, to North American Title Company, as trustee, for
Lender, as beneficiary (the "Deed of Trust"),  encumbering certain real property
commonly  known as 8 Acorn, Portola Valley,  California (the "Property"),  which
Borrowers occupy as their principal place of residence.





     III. Default and Acceleration:

     A. Unless  otherwise  prohibited by law, upon the  occurrence of any of the
following events, the Holder of this Note shall have the option,  without demand
or notice, to declare the entire balance of principal of this Note together with
all accrued interest to be immediately due and payable:

                1.  Borrowers  default in the payment of  principal  or interest
when due  pursuant  to the terms  hereof or  default in the  performance  of any
obligation  of  Borrowers  contained  in the Deed of Trust or any other  deed of
trust,   security  agreement  or  other  agreement   (including  any  amendment,
modification or extension  thereof) which may hereafter be executed by Borrowers
for the purpose of securing this Note;

                2. Borrowers  voluntarily  or by operation of law sell,  convey,
assign,  further  encumber or  otherwise  transfer  or agree to sell,  convey or
otherwise  transfer,  all or substantially all, or any portion of, or Borrowers'
interest in the Property;

                3. Ninety (90) days after the voluntary termination by Donald R.
Sellers of his employment with SciClone Pharmaceuticals, Inc.;

                4. One hundred eighty (180) days after the termination of Donald
R. Sellers' employment by SciClone  Pharmaceuticals,  Inc. for Cause, as defined
below;

                5. Three  hundred  sixty  (360) days  after the  termination  of
Donald R. Sellers' employment by SciClone Pharmaceuticals, Inc. without Cause.

As used herein,  the employment of Donald R. Sellers shall be deemed  terminated
for  Cause if a primary  factor  in the  termination  of his  employment  is the
failure by Mr. Sellers to comply with the instructions of the Board of Directors
of SciClone Pharmaceuticals,  Inc., gross negligence,  willful misconduct, fraud
or conviction of any crime.

         IV. Default Interest Rate: If Borrowers fail to make any payment within
fifteen  (15) days after any such  payment  becomes due and  payable,  Borrowers
agree to pay interest on the late  payment,  including  that portion of the late
payment  which  consists of past-due  interest,  at an annual rate (the "Default
Rate")  of three (3)  percent  in  excess  of the Note  Rate,  from the date the
payment was due until Borrowers pays in full all sums due under this Note.






         V. Attorneys'  Fees: In the event of any default  hereunder,  Borrowers
hereby promise to pay all costs of collection,  including reasonable  attorney's
fees  incurred by Lender  hereof on account of such  collection,  whether or not
suit is filed hereon.

         VI.  Waiver:  The  waiver by Lender  hereof of any breach of or default
under  any  term,  covenant  or  condition  contained  herein  or in  any of the
agreements  referred  to above  shall not be deemed to be a waiver or such term,
covenant or condition or any  subsequent  breach of or default under the same or
any other such term, covenant or condition.

         VII. No Usury:  It is the intent of Borrowers  and Holder that the rate
of interest on the  indebtedness  evidenced  hereby shall not exceed the maximum
rate  permitted  by  applicable  law and  accordingly,  if the rate of  interest
specified herein, or any other payments  specified herein or otherwise  required
to  be  made  by  Borrowers  or  received  by  Holder  in  connection  with  the
indebtedness  evidenced  hereby  and  deemed to be  interest,  shall  exceed the
maximum rate of interest permitted by applicable law then such payments,  to the
extent  they  exceed such  maximum  rate,  shall be deemed to have been made and
received inadvertently,  and shall for all purposes be deemed to be a payment of
and on account of the principal balance of the indebtedness evidenced hereby and
shall be applied accordingly or, at Holder's option, returned to Borrowers.

         VIII. General Provisions:  This Note shall be governed by and construed
in accordance with the laws of the State of California.  The makers,  guarantors
and  endorsers  of this Note hereby  severally  waive  presentment  for payment,
protest and demand,  notice of protest,  demand and dishonor and  nonpayment  of
this Note,  and consent that Lender may extend the time for payment or otherwise
modify the terms of payment  of any part or the whole of the debt  evidenced  by
this Note,  at the request of any person liable  hereon,  and such consent shall
not alter nor diminish the liability of any person.  Borrowers  hereby waive the
defense of the statute of  limitations  in any action on this Note to the extent
permitted by law.

         Borrowers:



                  Donald R. Sellers
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                  Donald R. Sellers



                  Jolice K. Sellers
          ------------------------------------
                  Jolice K. Sellers