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                                                                   EXHIBIT 10.11

                                PROMISSORY NOTE

                                                           San Diego, California
$4,500,000                                                         June 28, 1996

        1.   FOR VALUE RECEIVED, the undersigned, ALANEX CORPORATION, (the
"Maker"), promises to pay to AMGEN INC., a Delaware corporation ("Holder"), or
order, at 1840 DeHavilland Drive, Thousand Oaks, California 91320 or such other
place or places which the Holder may designate in writing from time to time, the
principal amount of Four Million Five Hundred Thousand Dollars ($4,500,000),
without interest.  The principal amount under this Note, plus any other amounts
then owing pursuant to this Note, shall be due and payable in full on June 28,
2001 (the "Maturity Date") without notice and without the need for any action or
election by Holder; provided, however, that: (a) if such date is not a normal
business day, such payment shall not be due until the first business day
thereafter and (b) upon a Default (as defined in that certain Termination and
Redemption Agreement between Maker and Holder effective as of the date hereof
(the "Agreement")) all such amounts shall automatically become immediately due
and payable without presentment, demand, protest or other notice of any kind,
all of which are hereby waived by Maker.

        2.   This Note may be prepaid in whole or in part at any time and any
prepayment shall be without penalty.

        3.   Principal shall be payable in lawful money of the United States of
America by check hand delivered to Lender or by federal funds wire upon Holder's
request, in which case applicable wiring instructions will be provided.

        4.   This Note is being executed pursuant to the Agreement.  Pursuant to
the terms of Section 6 of the Agreement, Maker has the option of converting this
Note to an interest bearing term note payable over three (3) years in the event
that it is unable to repay the entire principal balance of this Note when due on
the Maturity Date.  If on the Maturity Date of this Note, Maker has failed to
pay the entire principal amount, or alternatively, has
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failed to perform any of its obligations under Section 6 of the Agreement to
convert the Note, Maker shall be in default under this Note.  Upon any such
default, or any other default with respect to any payment due under this Note
(including, without limitation, failure to pay any principal when due), (i)
interest shall thereafter accrue on the entire unpaid principal balance
hereunder at the rate of ten percent (10%) per annum (on the basis of a 365-day
year and the actual number of days elapsed), subject to adjustment, if
necessary, to make the amount of interest charged not violate applicable usury
laws; (ii) Maker promises to pay all costs and expenses, including attorneys'
fees, incurred by the Holder hereof in collecting or attempting to collect the
indebtedness under this Note, whether or not any action or proceeding is
commenced; and (iii) Maker hereby waives the right to plead any and all statutes
of limitation as a defense to a demand hereunder to the full extent permitted by
law.

        5.   None of the provisions hereof and none of the Holder's rights or
remedies hereunder on account of past or future defaults shall be deemed to have
been waived by the Holder's acceptance of any past due installments or by an
indulgence granted by the Holder to Maker.

        6.   Maker hereby waives presentment, demand, protest and notice thereof
or of dishonor, and agrees that it shall remain liable for all amounts due
hereunder notwithstanding any extension of time or change in the terms of
payment of this Note granted by any holder hereof or any delay or failure by the
holder hereof to exercise any rights under this Note or the Agreement.

        7.   This Note shall be governed by and construed in accordance with the
laws of the State of California.
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        IN WITNESS WHEREOF, Maker has caused this Note to be duly executed the
day and year first above written.

                                       ALANEX CORPORATION,
                                       a California corporation


                                       By: /s/ Marvin R. Brown
                                          --------------------------------------
                                       Its: President



                                       By: /s/ Alexander Polinsky
                                          --------------------------------------
                                       Its: Secretary