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                                                                EXHIBIT 10.11(A)

                               AMENDMENT TO LEASE

This Amendment to Lease, made this 28th day of February, Two Thousand (2000), by
and between 580 Lancaster Associates, L.P., a general limited partnership
organized and existing under the Law of Pennsylvania whose present address is
1235 Westlakes Drive, Suite 425, Berwyn, PA 19312, hereafter called "Landlord",
and Animas Corporation, a corporation organized and existing under the law of
Delaware, whose present address is 590 Lancaster Avenue, Malvern, PA 19355
hereinafter called "Tenant".

                                WITNESSETH THAT:

WHEREAS, Landlord and Tenant hereto entered into an Agreement of Lease dated
September 25, 1998 providing for the leasing of office space by Tenant at 590
Lancaster Avenue, Malvern, PA 19355; and

WHEREAS, Tenant desires to extend the Term and expand the Lab Space and both
parties have agreed to the following changes and that effective August 1, 2000
("Effective Date"), the Agreement of Lease will be amended as follows:

         1.       The Term shall be extended three years, ending December 31,
                  2004.

         2.       Provided the work required to be performed by Landlord as
                  outlined in Article 5 of this Amendment to Lease is
                  substantially completed, then Article 35 shall be deleted in
                  its entirety and replaced with the following. Landlord will
                  use its best efforts to substantially complete the Lab Space
                  on or before August 1, 2000. The Lab Space shall be deemed
                  "Substantially Complete" and ready for occupancy on the date
                  which the work to be performed by Landlord in the Lab Space in
                  accordance with this Lease shall have been substantially
                  completed notwithstanding that insubstantial details of
                  construction, mechanical adjustment, or decoration remain to
                  be performed, the noncompletion of which would not interfere
                  with Tenant's use of the Premises. If for any reason
                  whatsoever the Lab Space is not Substantially Complete on or
                  before September 1, 2000, then Landlord shall abate Fixed Rent
                  one day for each day beyond September 1, 2000 the Lab Space is
                  not Substantially Complete and shall abate Fixed Rent two days
                  for each day beyond September 15, 2000 the Lab Space is not
                  Substantially Complete. Notwithstanding anything to the
                  contrary herein, Tenant may terminate this Lease by written
                  notice to Landlord given at any time after October 1, 2000 if
                  the Premises are not Substantially Complete.

                  LAB SPACE.

                  (a)      DEMISE. In addition to the area defined in Article 2
                  of this Lease, Landlord does hereby lease and demise to Tenant
                  and Tenant does hereby hire and take from Landlord, for the
                  term and subject to the provisions hereof, the space
                  (hereinafter, together with all fixtures, equipment,
                  improvements, installations and appurtenances which at the
                  commencement of or during the term of this Lease are thereto
                  attached, referred to as the "Lab Space") cross-hatched on the
                  floor plan (the "Floor Plans") attached hereto as Exhibit "D".
                  To identify the obligations and responsibilities of Landlord
                  and Tenant with regard to the Lab Space, the Lab Space is
                  included within the definition of the "Premises". The Lab
                  space is approximately 24,000 square feet.

                  (b)      USE. Landlord represents that Tenant may use the Lab
                  Space for computer operations, laboratory, warehouse and
                  distribution and light assembly and testing.

                  (c)      RENT. The minimum fixed annual rent for the Lab Space
                  shall be the sum of Two Hundred Forty Five Thousand Seven
                  Hundred Forty Nine and 92/100 Dollars ($245,749.92) lawful
                  money of the United States of America, payable in equal
                  monthly installments in advance and without demand, notice,
                  set-off or deduction, except as otherwise expressly provided
                  in this Lease, in the sum of Twenty Thousand Four Hundred
                  Seventy Nine 16/100 Dollars ($20,479.16) on the first day of
                  each and every month during the Term. The Fixed Rent for the

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                  Lab Space for the first Extended Term shall be Two Hundred
                  Forty One Thousand Nine Hundred Twenty Dollars ($241,920.00)
                  per year.

         3.       Retail Space.

                  (a)      Demise. In addition to the area defined in Article 2
                  and Article 35 of this Lease, Landlord does hereby lease and
                  demise to Tenant and Tenant does hereby hire and take from
                  Landlord, for the term and subject to the provisions hereof,
                  the space (hereinafter, together with all fixtures, equipment,
                  improvements, installations and appurtenances which at the
                  commencement of or during the term of this Lease are thereto
                  attached, referred to as the "Retail Space") cross-hatched on
                  the floor plan (the "Floor Plans") attached hereto as Exhibit
                  "D". To identify the obligations and responsibilities of
                  Landlord and Tenant with regard to the Retail Space, the
                  Retail Space is included within the definition of the
                  "Premises". The Retail Space is approximately 6,000 square
                  feet. The Retail Space will be made available for Tenant's
                  occupancy at the same time as the Lab Space.

                  (b)      Use. Landlord represents that Tenant may use the
                  Retail Space for offices, computer operations, laboratory,
                  warehouse and distribution and light assembly and testing.

                  (c)      Rent. The minimum fixed annual rent for the Retail
                  Space shall be the sum of Eighty Four Thousand Four Hundred
                  Eighty Dollars ($84,480.00) lawful money of the United States
                  of America, payable in equal monthly installments in advance
                  and without demand, notice, set-off or deduction, except as
                  otherwise expressly provided in this Lease, in the sum of
                  Seven Thousand Forty Dollars ($7,040.00) on the first day of
                  each and every month during the Term. The Fixed Rent for the
                  Retail Space for the first Extended Term shall be Eighty Eight
                  Thousand Five Hundred Dollars ($88,500.00) per year.

         4.       Articles 37 and 38 shall be deleted, in their entirety.

         5.       Landlord shall, at Landlord's cost, complete the improvements
                  outlined below on or before the Effective Date of this
                  Amendment to Lease:

                  a)       Landlord shall install, in the warehouse space, HVAC
                           in sufficient quality and quantity to maintain
                           acceptable temperature and air quality for Tenant's
                           use as a office area. Such quantity and quality shall
                           not be less than that existing in the existing office
                           area. Such HVAC shall include base units, reasonable
                           quantities of duct, diffusers, and thermostat
                           controls.

                  b)       Landlord shall provide electrical panels wired to the
                           main distribution panel throughout the warehouse
                           space in locations mutually determined by Landlord
                           and Tenant with the cost therefore not to exceed
                           $3,500.00.

                  c)       Landlord shall at its own expense, complete the
                           parking area as outlined on Exhibit G. Such parking
                           shall be expanded to not less that 180 parking spaces
                           and will be for Tenant's exclusive use at all times.

         6.       In addition to Landlord's work as provided in Article 5 above,
                  Tenant shall perform work at its own expense to prepare the
                  "Lab Space" for its use. Tenant agrees to install the ceiling
                  with 3 1/2 inches of insulation at a height of 12 feet.
                  Tenant shall not be responsible to remove the improvements at
                  the end of the Term.

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         7.       Option to Terminate. Tenant shall have the option to terminate
                  this Lease ("Option to Terminate") upon the following terms
                  and conditions:

                  a)       Tenant shall give Landlord not less than nine months
                           written notice ("Notice to Terminate") provided such
                           notice shall not been given prior to March 31, 2001.

                  b)       In addition to any amounts owed in accordance with
                           this Lease, Tenant shall pay the sum of $3,472.22
                           multiplied by the remaining months of the Term. Such
                           payment shall be due ninety days prior to the
                           effective date of the termination ("Termination
                           Fee"). (i.e. Notice to Terminate: November 1, 2002;
                           Termination Date: July 31, 2003; Termination Fee:
                           $59,027.74 (17 x $3,472.22); Date Due: April 30,
                           2003.)

                  c)       In the event Tenant exercises its Option to Terminate
                           and pays the Termination Fee as required above, the
                           Lease shall terminate as if the date were the date
                           originally set forth herein for the expiration of the
                           Term.

         8.       Access. With reasonable prior notice, Tenant shall have
                  access, after the execution of this Amendment to Lease, to the
                  expansion Lab and Retail Space for its architects, engineers,
                  and construction representatives to enable Tenant to prepare
                  plans and specifications for its work in the expansion space.
                  Such reasonable access shall not interfere with the existing
                  Tenant's use of the space.

         9.       All Capitalized terms in this Amendment will have the meaning
                  set forth in the Lease, except as specifically amended hereby.

         10.      All of the terms, conditions, and provisions of the Lease are
                  incorporated herein by reference as fully as though set forth
                  in this Agreement.

         11.      All other lease terms and conditions to remain the same.

                  IN WITNESS WHEREOF, the parties hereto have executed this
                  Amendment to Lease on the day and year aforesaid.

         Landlord:

         580 LANCASTER ASSOCIATES, L.P.
         1235 WESTLAKES DRIVE
         BERWYN, PA 19312

         By: /s/ Frank Fox
             --------------------------------

         Attest: ____________________________

         Tenant:

         ANIMAS CORPORATION
         a Delaware Corporation

         By: /s/ KATHERINE D CROTHALL
             --------------------------------

         Attest: /s/ Paul Wolfson