FOURTH ADDENDUM TO LEASE BETWEEN ANDRX CORPORATION
           AND NEWTOWN COMMERCE CENTER LTD., AS SUCCESSOR IN INTEREST
                    TO NEWTOWN ASSOCIATES LIMITED PARTNERSHIP

         This Fourth Addendum is dated the 23rd day of July, 1996 and is by and
between Andrx Corporation, a Florida corporation ("Tenant") and Newtown Commerce
Center, Ltd., as successor in interest to Newtown Associates Limited Partnership
("Landlord").

                                   WITNESSETH:

         WHEREAS, Landlord and Tenant entered into that certain Lease Agreement
dated April 23, 1993 (the "Original Lease"), pertaining to Suites 201 to 203 in
that certain building located at 4001 S.W. 47th Avenue, Davie, Florida 33314
("Building Two"); and

         WHEREAS, the Original Lease has been modified and amended pursuant to
those certain Addenda dated July 28, 1994, May 1, 1995 and October 30, 1995, in
order to, among other things, add Suites 204, 205, 206, 207, 208, 209, 210, and
211, in Building Two, to the Original Lease and to grant Tenant a right of first
refusal with respect to the remaining space in Building Two (the "Addenda"); and

         WHEREAS, the Original Lease has also been modified and amended pursuant
to that certain Option to Lease, dated April 30, 1993 (the "Option") and a
Non-Disturbance, Attornment and Subordination Agreement dated August 25, 1993
(the "Non-Disturbance Agreement" and the Original Lease, the Addenda, the
Option, and the Non-Disturbance Agreement are herein collectively referred to as
the "Lease");

         NOW, THEREFORE, in consideration of the premises and the sum of Ten
Dollars ($10.00) and other good and valuable consideration, Landlord and Tenant
hereby agree as follows:

         1. Incorporation of Recitals. The Recitals set forth above are true and
correct and are hereby incorporated by reference.

         2. Exercise of Option. Tenant hereby exercises its option with respect
to Suites 213 and 214, and agrees to lease those suites, comprising
approximately 4,100 square feet, beginning as of June 1, 1996. That additional
space, together with the other suites presently leased by Tenant in Building
Two, shall become part of the Lease, making a combined total of 37,400 square
feet leased by Tenant pursuant to the Lease.

         3. Term and Delivery of Space. The term of the Lease, with respect to
any additional space acquired by Tenant pursuant to the exercise of its option,
shall commence on the first day of the month after such space is vacated, and
shall expire on May 31, 2003. Notwithstanding the foregoing, Landlord shall
allow Tenant to immediately use such additional space without any payment
obligation.

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         4. Field Measurement. Tenant shall be entitled to a "Field Measurement"
of any additional space which it acquires, and of the total rentable square
footage of the subject building.

         5. Rental Rate. Commencing on the first day of the month after Tenant
gains possession of any additional space in Building Two, Tenant agrees to pay
Landlord the total annual rental set forth below for the suites it occupies,
plus additional Florida sales tax (presently at 6% per annum), in accordance
with the following schedule:

                    Period                        :|         Rate per Sq. Ft.

                    Until May 1998                           $7.15

                    June 1998 to May 2001
                    (36 months)                              $7.40

                    June 2001 to May 2003
                    (36 months)                              $7.65

         The annual rent shown above includes operating expenses.

         6. Option: Deliverv of Suite 215. Tenant is hereby given the option of
causing Landlord to vacate Suite 215 during the Lease Term. Upon Tenant's
written request, Landlord hereby agrees to vacate Suite 215 as quickly as may be
practicable. If such option is exercised, Tenant hereby agrees to pay Landlord's
moving expenses and any expenses reasonably incurred in connection with building
out or decorating the space in Newtown Commerce Centre which Landlord moves
into. This provision is subject to a space being available facing S.W. 47th
Avenue.

         7. Other Provisions. All other terms and conditions of the Lease shall
remain the same.

         IN WITNESS WHEREOF, Landlord and Tenant have duly executed this fourth
Addendum on the date set forth above.

Tenant:                                   Landlord:

ANDRX CORPORATION                         NEWTOWN COMMERCE CENTER, LTD.
                                          By: ADLER MANAGEMENT SERVICES,
                                          INC.

/S/ SCOTT LODIN                           /S/ BRETT HARRIS
------------------------                  --------------------------------------
Scott Lodin, V.P./General Counsel         Brett Harris, Executive Vice President