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                                                                   EXHIBIT 10.61
                                                                    Page 1 of 5

                   AMENDMENT NO. 1 TO 1434 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 11,200 square feet in that certain concrete
block one story office and factory building located at 1434 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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     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:     $4,928.00 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)  ADJUSTMENT 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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          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
               ------                                 ---------------

               June 1, 2000 - June 30, 2000:          $5,000.00
               July 1, 2000 - July 31, 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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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                                 LEE INC.

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:  5/24/00
     -----------------------------          --------------------------------


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