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                                                                    EXHIBIT 10.7

July 17, 2002

Beth A. Burnside, Ph.D.
5404 Huntington Parkway
Bethesda MD 20814

Dear Beth:

On behalf of Advancis Pharmaceutical Corporation, I am pleased to extend this
offer to you for the position of Senior Director, Formulation Development
reporting to Colin E. Rowlings, Ph.D., Vice President, Pharmaceutical Research &
Development. Your initial base salary will be $160,000.00 per year with a
starting date of September 3, 2002. Your salary will be subject to normal
periodic review based on corporate policy, your performance, and other factors
considered by the company in making salary determinations.

Stock Options: You will be eligible to participate in the Advancis
Pharmaceutical Stock Option Plan in accordance with the terms and conditions of
the Stock Option Plan, as may be amended from time to time. This initial stock
option grant is contingent upon approval of the Board of Directors, which should
occur at their next scheduled meeting after your hire. I will recommend to the
board an option grant of 40,000 shares.

Bonus Eligibility: You will be eligible to participate in the Advancis
Pharmaceutical Bonus Plan. Based on your job level, you will be eligible for an
annual bonus of up to 15%. Bonuses are contingent upon both employee and company
performance.

Vacation: You will be granted paid vacation time in the amount of 4 weeks per
calendar year. Unused vacation days cannot be carried over from one calendar
year into the next.

Benefits: You will be eligible to participate in Advancis Pharmaceutical's
health, dental, disability, and life insurance plans, as well as various other
employee benefits as outlined in the attached Benefits Summary.

At-Will Employment: Advancis Pharmaceutical is an "at will" employer. This means
your employment is not for any definite period of time, and either you or
Advancis Pharmaceutical may terminate such employment for any reason, at any
time, with or without cause and with or without notice. Similarly, as an
employee of Advancis Pharmaceutical, you will be subject to such employment
policies and terms and conditions as Advancis Pharmaceutical may adopt or modify
from time to time, and nothing in this offer letter or told or given to you
during your employment should be interpreted as a guarantee or contract.

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Beth A. Burnside, Ph.D.
July 17, 2002
Page 2 of 2

As an employee, you will be required to sign the Assignment of Invention,
Non-Disclosure and Non-Competition Agreement. We understand from you that this
offer and your employment with Advancis Pharmaceutical Corporation are not in
conflict with any existing or previous employment agreement or non-competition
agreement.

Please indicate your acceptance of this offer of employment by signing and
dating below, and returning this letter to the Human Resources Department at
Advancis Pharmaceutical in the enclosed envelope. You may keep the enclosed copy
for your records.

Beth, we are excited to make you this offer and hope that you join us. We look
forward to your start date, and your new career at Advancis Pharmaceutical
Corporation.

Sincerely,

/s/ Edward M. Rudnic

Edward M. Rudnic, Ph.D.
President & CEO

EMR:jmc

Enclosure

cc: Colin E. Rowlings, Ph.D.

Accepted:

   /s/ Beth A. Burnside                              July 23, 2002
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Beth A. Burnside, Ph.D.                                   Date