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                                                                  EXHIBIT 10.59
                                                                  Page 1 of 5


                  AMENDMENT NO. 1 TO 1470 SANTA ANITA LEASE

       THIS AMENDMENT NO. 1 TO 1434 SANTA ANITA LEASE ("AMENDMENT NO. 1") is
made and entered as of May 25, 2000 ("EFFECTIVE DATE"), by and between ART
WEISS, an individual ("LESSOR"), and LEE PHARMACEUTICALS, a California
corporation ("LESSEE").

                                    RECITALS

       A.  Lessor and Lessee are parties to that certain Standard Industrial
Lease - Gross dated April 16, 1990 (the "LEASE"), pursuant to which Lessee
leased from Lessor approximately 8,400 square feet in that certain concrete
block one story office and factory building located at 1470 Santa Anita
Avenue in South El Monte, California (the "PREMISES").

       B.  Lessor and Lessee are also parties to that certain Settlement
Agreement of even date herewith ("SETTLEMENT AGREEMENT"). In order to settle
the Disputes referenced in the Settlement Agreement, Lessor and Lessee agreed
to amend this Lease on the terms and conditions set forth below. Capitalized
terms not otherwise defined in this Amendment No. 1 shall have the same
meaning as set forth in the Lease or in the Settlement Agreement, as
applicable.

       NOW, THEREFORE, in consideration of the mutual covenants and
agreements herein contained, and other good and valuable consideration, the
parties do hereby agree as follows:

       1.  RECITALS.  The foregoing Recitals are incorporated by reference as
if fully set forth herein, and the terms and provisions of the Settlement
Agreement are specifically incorporated herein by reference as if fully set
forth herein.

       2.  AMENDMENTS TO LEASE. The Lease is hereby amended as follows:

           a.  EXERCISE OF FIRST OPTION TO EXTEND TERM.  Lessee hereby
exercises it's option to extend the term of this Lease from December 1, 2000
up to and including November 30, 2005 ("FIRST EXTENSION PERIOD"). Lessor
hereby accepts said exercise.

           b.  PARAGRAPH 4 - RENT.  Paragraph 4 is hereby deleted in its
entirety and replaced with the following new Paragraph 4:

      "4.  RENT.

           4.1  MONTHLY BASE RENT.  Lessee agrees to and shall pay to Lessor
      monthly base rent for the Premises for the following periods (inclusive
      of the First Extension


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                                                                  Page 2 of 5

Period) in the amounts set forth below. Lessee shall pay Lessor each payment
of monthly base rent, in advance, on the first (1st) day of each month during
each period of the term of this Lease:

           PERIOD                                 MONTHLY BASE RENT
           ------                                 -----------------

      (a)  MARCH 1, 2000 - NOVEMBER 30, 2000:     $3,696.00 per month

      (b)  DECEMBER 1, 2000 - NOVEMBER 30, 2002:  On December 1, 2000,
           the monthly base rent under the Lease in effect as of November 30,
           2000 shall be multiplied by a fraction, the numerator of which is
           the Consumer Price Index Los Angeles-Riverside-Orange County (All
           Items - All Urban Consumers)(1982-84 = 100)(the "INDEX") for
           December, 2000, and the denominator of which shall be 163.5 (which
           was the Index for December, 1998). The amount so calculated shall
           constitute the new monthly base rent for the period December 1,
           2000 through November 30, 2002, provided, however, in no event
           shall the new monthly base rent for said period be less than the
           monthly base rent payable during November, 2000.

      (c)  DECEMBER 1, 2002 - NOVEMBER 30, 2004:  On December 1, 2002, the
           monthly base rent in effect as of November 30,  2002 shall be
           multiplied by a fraction, the numerator of which is the Index for
           December, 2002, and the denominator of which shall be the Index
           for December, 2000. The amount so calculated shall constitute the
           new monthly base rent for the period December 1, 2002 through
           November 30, 2004, provided, however, in no event shall the new
           monthly base rent be less than the monthly base rent payable
           during November, 2002.

      (d)  DECEMBER 1, 2004 - NOVEMBER 30, 2005:  On December 1, 2004, the
           monthly base rent in effect as of November 30, 2004 shall be
           multiplied by a fraction, the numerator of which is the Index for
           December, 2004, and the denominator of which shall be the Index
           for December, 2002. The amount so calculated shall constitute the
           new monthly base rent for the period December 1, 2004 through
           November 30, 2005, provided, however, in no event shall the new
           monthly base rent be less than the monthly base rent payable
           during November, 2004.

      (e)  ADJUSTMENTS PENDING RECEIPT OF FINAL INDEX.  For each of the
           adjustment dates referenced above, pending receipt of the required
           Index Lessee shall pay Lessor an estimated adjusted monthly base
           rent, reasonably determined by the Lessor based on the then
           available Index information. Upon notification of the actual
           adjustment after publication of the required Index, Lessee shall
           be credited with any overpayments against the next due monthly
           base rent, or if applicable Lessee shall pay Lessor any
           underpayments with the next due monthly base rent."


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                                                                  Page 3 of 5

            4.2  NEGOTIATED RENT FOR SPECIFIED PERIODS.  In addition to the
      monthly base rent referenced in PARAGRAPH 4.1 above, Lessee shall also
      pay to Lessor the following amounts of additional "NEGOTIATED RENT" for
      the Premises for the following periods. Each payment of Negotiated Rent
      shall be due and payable, in advance, on the first (1st) day of
      the month for the period specified:

              PERIOD                                     NEGOTIATED RENT
              ------                                     ---------------

              August 1, 2000 - August 30, 200:           $5,000.00
              September 1, 2000 - September 30, 2000:    $5,000.00"

            c.  GRANT OF SECOND OPTION TO EXTEND TERM.  Lessee is hereby
granted the conditional right and option ("SECOND OPTION TO EXTEND") to
extend the term of this Lease for a single additional period of five (5)
consecutive years (the "SECOND EXTENSION PERIOD"), on the same terms and
conditions in effect under this Lease immediately prior to commencement of the
Second Extension Period, except that monthly base rent shall be increased to
the Second Extension Period Monthly Base Rent (defined below). If the Second
Option to Extend is timely exercised, then the Second Extension Period shall
commence on December 1, 2005 and shall terminate on November 30, 2010. Lessee
shall have no further rights or options to extend the term of this Lease.
The Second Option to Extend is personal to Lessee, may only be exercised by
Lessee, and may be exercised only by Lessee delivering to Lessor irrevocable
and unconditional written notice thereof ("NOTICE OF EXERCISE OF SECOND
OPTION") not less than one hundred eighty (180) calendar days and not more
than three hundred sixty (360) calendar days prior to commencement of the
Second Extension Period. If Lessee for any reason fails to timely exercise
the Second Option to Extend on the terms and conditions set forth above, then
the Second Option to Extend shall terminate, expire and have no further force
or effect. Further, if Lessee for any reason fails to timely make any payment
of Negotiated Rent pursuant to this Lease in good and drawable funds on (or
before, at Lessee's option) the date when due, or if Lessee fails to timely
make any payment of Negotiated Rent to any other Lessor under any of the
other Leases (as those terms are defined in the Settlement Agreement) in good
and drawable funds on (or before, at Lessee's option) the date when due, then
in each instance and without further notice the Second Option to Extend under
this Lease shall automatically terminate, expire and have no further force or
effect. For purposes of this Lease, the phrase "SECOND EXTENSION PERIOD
MONTHLY BASE RENT" shall mean as follows:

                (i)  DECEMBER 1, 2005 THROUGH NOVEMBER 30, 2007.  At
commencement of the Second Extension Period, the monthly base rent under this
Lease in effect as of November 30, 2005 shall be multiplied by a fraction,
the numerator of which is the Index for December, 2005, and the
denominator of which shall be the Index for December, 2003. The amount so
calculated shall constitute the new monthly base rent for the period December
1, 2005 through November 30, 2007, provided, however, in no event shall the
new monthly base rent for said period be less than the monthly base rent
payable during November, 2005.

                (ii) DECEMBER 1, 2007 THROUGH NOVEMBER 30, 2009. On December
1, 2007, the monthly base rent in effect as of November 30, 2007 shall be
multiplied by a fraction, the numerator of which is the Index for December,
2007, and the denominator of which shall be


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                                                                  Page 4 of 5

the Index for December, 2005. The amount so calculated shall constitute the
new monthly base rent for the period December 1, 2007 through November 30,
2009, provided, however, in no event shall the new monthly base rent be less
than the monthly base rent payable during November, 2007.

                (iii) DECEMBER 1, 2009 THROUGH NOVEMBER 30, 2010. On December
1, 2009, the monthly base rent in effect as of November 30, 2009 shall be
multiplied by a fraction, the numerator of which is the Index for December,
2009, and the denominator of which shall be the Index for December, 2007. The
amount so calculated shall constitute the new monthly base rent for the period
December 1, 2009 through November 30, 2010, provided, however, in no event
shall the new monthly base rent be less than the monthly base rent payable
during November, 2009.

                 (iv) ADJUSTMENTS PENDING RECEIPT OF FINAL INDEX.  For each of
the adjustment dates referenced above, pending receipt of the required Index
Lessee shall pay Lessor an estimated adjusted monthly base rent, reasonably
determined by the Lessor based on the then available Index information. Upon
notification of the actual adjustment after publication of the required
Index, Lessee shall be credited with any overpayments against the next due
monthly base rent, or if applicable Lessee shall pay Lessor any underpayments
with the next due monthly base rent.

                 (v)  SECOND OPTION TO EXTEND IS PERSONAL TO LESSEE.
Lessee's exercise of the Second Option to Extend Term shall not operate to
cure any default by Lessee of any of the terms or provisions in this Lease,
nor to extinguish or impair any rights or remedies of Lessor arising by
virtue of such default. If this Lease, any term hereof or Lessee's right to
possession of the Premises shall terminate in any manner whatsoever before
Lessee exercises the Second Option to Extend, or if Lessee shall have
subleased or assigned all or any portion of the Premises without Lessor's
prior written consent, then immediately upon such termination, sublease or
assignment, the Second Option to Extend shall simultaneously terminate and
become null and void. The Second Option to Extend is personal to Lessee. In
no circumstance shall the assignee under a complete or partial assignment of
this Lease, or a subtenant under a sublease of all or any portion of the
Premises, have the right to exercise the Second Option to Extend. Unless
Lessor otherwise agrees in writing, any purported assignment of the Lease by
Lessee or any purported sublease by Lessee of any part of the Premises after
the date Lessee purportedly exercised the Second Options to Extend and before
commencement of the Second Extension Period shall automatically and
retroactively cause said exercise to become null and void and of no force or
effect, in which event the term of this Lease shall terminate and expire on
November 30, 2005. Time is of the essence of this provision.

      3.  WHOLE AGREEMENT.  This Amendment No. 1 and the Settlement Agreement
together set forth the entire agreement between the parties with respect to
the matters set forth herein. There have been no additional oral or written
representations or agreements concerning the Premises or the Lease. As
amended herein, the Lease shall remain in full force and effect. In case of
any inconsistency between the provisions of the Lease and this Amendment No. 1,
the provisions of this Amendment No. 1 shall govern and control; and in case
of any inconsistency


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                                                                  Page 5 of 5

between the provisions of this Lease (as amended) and the Settlement
Agreement, the provisions of the Settlement Agreement shall govern and
control.

       IN WITNESS WHEREOF, the Lessor and Lessee have duly executed this
Amendment No. 1 as of the date set forth below, in South El Monte,
California. Notwithstanding the actual date of execution, this Amendment No.
1 shall for all purposes be deemed effective as of the Effective Date first
above written.


LESSOR                                 LESSEE
------                                 ------
ART WEISS, an individual,              LEE PHARMACEUTICALS, INC., a
                                       California corporation,

/s/ Art Weiss                          By:  /s/ Ronald G. Lee
--------------------------                 --------------------------
Art Weiss                                  Ronald G. Lee, President


Date:  5-22-2000                       Date:  5-24-2000
      --------------------                   ------------------------




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