EXHIBIT 10.11

                        ADDENDUM TO EMPLOYMENT AGREEMENT

         This addendum ("Addendum") dated as of the 1st day of September, 1997,
between Columbia Laboratories Inc. ("Columbia") a corporation organized and
existing under and by virtue of the laws of the State of Delaware, having its
principal place of business at 2665 South Bayshore Drive, Miami, Florida 33133
(hereinafter referred to as the "Company"), and Nicholas A. Buoniconti, who
resides at______________, Florida 33131 (hereinafter referred to as "Employee").

                                   WITNESETH:

         WHEREAS, the Company is and will be engaged in the development,
testing, registration, manufacturing, licensing, marketing, and selling of
pharmaceutical products; and

         WHEREAS, the employee, by reason of his knowledge, skill and ability is
uniquely qualified to aid the Company in the development, testing, registration,
manufacturing, licensing, marketing, and selling of pharmaceutical products; and

         WHEREAS, the Company is desirous of continuing the employment of the
Employee to provide assistance to the Company in the development, testing,
registration, manufacturing, licensing, marketing, and selling of pharmaceutical
products and the Employee is desirous of continuing his employment with the
Company to assist it in the development, testing, registration, manufacturing,
licensing, marketing, and selling of pharmaceutical products; and


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         WHEREAS, the Company and Employee desire to enter into this Addendum to
the Employee's employment agreement (the "Agreement") so that the rights,
duties, benefits and obligations of each in respect of the employment of the
Employee for and by the Company will be fully set forth under the terms and
conditions stated both in the Agreement and herein upon the execution hereof;
and

         WHEREAS, the terms of the Employee's Agreement shall only be modified
by the specific terms and conditions set forth herein, which shall modify and
supersede any similar provisions in the Employee's employment agreement, if any,
and any inconsistency between this Addendum and the Employee's Agreement shall
be resolved by the provisions hereinafter set forth.

         NOW, therefore, in consideration of the mutual promises contained
herein, the payment of Ten ($10.00) dollars by each party to the other, the
receipt of which is hereby duly acknowledged, and for other good and valuable
consideration, the Company and Employee further agree as follows:

         1. The Employee retroactive to and effective as of September 1, 1997,
shall receive for the discharge of his duties and activities on behalf of the
Company as provided for herein, an annual salary ("Base Salary") of Two Hundred
Eighty Thousand and No/00 ($280,000.00) dollars, which shall be paid by the
Company to the Employee in equal and regular installments not less frequently
than monthly, in accordance with the Company's policy for payment of executive
salaries.

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         2. NOTICES

            Any notice required or permitted to be given under this addendum
and the Employee's employment agreement shall be sufficient if in writing and
actually delivered, or if sent either by Federal Express, or postage prepaid, by
certified mail, return receipt requested, with a copy by ordinary mail, to the
addresses below:

                  As to Company:               2665 South Bayshore Drive
                                               Miami, Florida 33133

                  As to Employee:              445 Grand Bay Drive, Apt 803
                                               Miami, Florida 33131

or to such other address as either party shall designate by written notice to
the other.
                  
         3. ENTIRE ADDENDUM

            This Addendum contains the entire agreement and understanding of the
Company and the Employee with respect to the subject matter hereof, and shall
incorporate, merge and supersede all prior agreements and understandings had
between the Company and the Employee, either oral or written, if any. No
modification, change or amendment to this addendum, shall be binding upon the
Company or the Employee unless the same is in writing, and signed by the party
against whom enforcement of the modification, change or amendment is sought to
be enforced

         4. MISCELLANEOUS

            (a) This Addendum and the implementation of it shall be subject to
and governed by the laws of the State of Florida, and any legal proceedings
relating to (i) the interpretation or

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enforcement of any of the provisions of this Addendum, or (ii) any dispute
relating to the employment relationship created by the addendum, shall only be
brought in the Circuit Court of the State of Florida, in and for the County of
Dade.

            (b) The Article headings contained herein are for reference purposes
only and shall not in any way affect the meaning or the interpretation of this
Addendum.

            (c) The failure of any provision of this Addendum shall in no manner
affect the right to enforce the remainder of this Addendum, and the waiver by
either The Company or the Employee of any breach of any provision of this
addendum shall not be construed to be a waiver by the Company or the Employee of
any succeeding breach of such provision or a waiver by such party of any breach
of any other provision of this Addendum.

         IN WITNESS WHEREOF, the parties hereto have executed this Addendum on
September 29, 1997.
                                                                       


                                             Employee:
Witness:


/s/ DAVID L. WEINBERG
---------------------
    David L. Weinberg                        /s/ NICHOLAS A. BUONICONTI
                                             --------------------------
                                             NICHOLAS A. BUONICONTI

                                             Company:
                                             COLUMBIA LABORATORIES, INC.

Witness:


/s/ DAVID L. WEINBERG
---------------------
    David L. Weinberg                        /s/ WILLIAM J. BOLOGNA
                                             --------------------------
                                             By: WILLIAM J. BOLOGNA
                                                 Chairman of the Board

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