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                                                                 EXHIBIT 10.63
                                                                 Page 1 of 5



                   AMENDMENT NO. 1 TO 1500 SANTA ANITA LEASE

     THIS AMENDMENT NO. 1 TO 1500 SANTA ANITA LEASE ("AMENDMENT NO. 1") is
made and entered as of May 25, 2000 ("EFFECTIVE DATE"), by and between ART
WEISS, INC., a California corporation ("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 17,600 square feet in that certain concrete
block one story office and factory building located at 1500 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:


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     "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 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:        $7,744.00 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


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                 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."

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

                 December 1, 2000 - December 1, 2000:       $5,000.00
                 January 1, 2001 - January 31, 2001:        $5,000.00
                 February 1, 2001 - February 28, 2001:      $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


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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 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.


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     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 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, INC., a                     LEE PHARMACEUTICALS, INC., a
California corporation,                California corporation,

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

Date:   5-22-2000                      Date:  5/24/00
     -----------------------------          -------------------------


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