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                                                                   EXHIBIT 10.10

Employment Agreement with Michael E. Petrone, M.D.

December 20, 2000

Dr. Michael E. Petrone

Dear Dr. Petrone:

I am pleased to offer you the position of Vice President, Clinical Research with
Magainin Pharmaceuticals Inc., reporting to the Dr. Kenneth Holroyd, Executive
Vice President. Your base salary will be $15,000.00 per month ($180,000/year).
Contingent upon your acceptance of this offer, it is expected that the
Compensation Committee of the Board of Directors will grant to you at its next
meeting options to purchase 50,000 shares of Magainin Common Stock, exercisable
at the fair market value underlying common stock on the date of such meeting.
These options will have a term of 10 years and vest at the rate of 25% per year.
As with all Magainin options, the grant will be subject to execution of a stock
option agreement in the form specified by the Compensation Committee.

If your employment is terminated without cause, you will receive your monthly
base salary, including health benefits through COBRA, for six (6) months
following the date of termination.

Upon the commencement of your employment with the Company, you will be expected
to execute the Company's Drug Free Workplace Policy, Proprietary Information
Agreement, Policy Statement on Securities Trading by Magainin Personnel, and
Corporate Governance - Conflict of Interest Policy, each in the form previously
provided to you. Magainin may have already provided you with certain of its
confidential business or scientific information, which it expects you to keep
confidential, and to use only to further Magainin's legitimate business
interests. Just as Magainin expects you to keep confidential its business or
scientific information, Magainin also expects you to honor your obligations to
your former employers with respect to maintaining the confidentiality of their
business or scientific information.

You will be eligible for twenty (20) days vacation per year. Vacation accrues
proportionate to months employed. Employees are encouraged to take their
vacations yearly. However, up to five (5) days of unused vacation time can be
carried over into next year with supervised approval. In addition, you will be
eligible for the benefits package available to all employees. Enclosed is a
summary of the benefits.
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All the terms and conditions of this Agreement shall be binding upon and inure
to the benefit and be enforceable by the respective heirs, representatives,
successors (including any successor as a result of a merger or similar
reorganization) and assigns of the parties hereto, except that your duties and
responsibilities hereunder are of a personal nature and shall not be assignable
in whole or in part by you.

We look forward to your joining us at Magainin Pharmaceuticals Inc. Please
indicate your acceptance of this offer, which is for at will employment, by your
signature below. This offer of employment will remain in effect until Wednesday,
December 27, 2000. We have agreed that your start date will be Monday, January
8, 2001 at 8:30 A.M., however, this is flexible. Please do not hesitate to speak
with me concerning any questions you may have.

                                          Sincerely,

                                          /s/ Roy C. Levitt, M.D.
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                                          Roy C. Levitt, M.D.
                                          President and Chief Executive Officer