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                                                                    EXHIBIT 10.5

                       ADVANCIS PHARMACEUTICAL CORPORATION

                         EXECUTIVE EMPLOYMENT AGREEMENT

                  THIS EXECUTIVE EMPLOYMENT AGREEMENT (this "Agreement") is made
this 3rd day of January, 2003 by and between Robert J. Guttendorf, Ph.D., a
resident of Gaithersburg, Maryland (the "Employee"), and Advancis Pharmaceutical
Corporation, a corporation organized and existing under the laws of the State of
Delaware (the "Company").

BACKGROUND

                  The Company is engaged in the business of developing,
improving and promoting antibiotic therapies and the delivery and dosage of
antibacterials, as well as extending the market and patent life of important
anti-infectives and oncology (as may be modified or expanded by the Company
during the term of this Agreement, collectively and individually, the
"Business").

                  The Company desires to employ the Employee and the Employee
desires to be employed by the Company, upon the terms and conditions set forth
in this Agreement.

                  NOW, THEREFORE, in consideration of the mutual covenants and
obligations contained herein, and intending to be legally bound, the parties,
subject to the terms and conditions set forth herein, agree as follows:

                  1.       EMPLOYMENT AND TERM. The Company hereby employs the
Employee and the Employee hereby accepts employment with the Company, as Vice
President, Preclinical Research, (the "Position") commencing on September 03,
2002 (the "Commencement Date"). Employee is employed by the Company on an at
will basis. The Employee shall be entitled to terminate this Agreement at any
time upon ninety (90) days prior written notice to the Company. The Company
shall be entitled to terminate this Agreement at any time subject to the
provisions of Section 8 hereof. (The entire period of time during which the
Employee is employed by the Company is referred to herein as the "Term").

                  2.       DUTIES. During the Term, the Employee shall serve the
Company faithfully and to the best of his ability and shall devote his full
time, attention, skill and efforts to the performance of the duties required by
or appropriate for the Position. Subject to the oversight of the President &
CEO, or at such time as a Chief Scientific Officer is appointed, the Employee
shall (i) have responsibility for the planning, directing and prioritizing
preclinical research and development activities, and scientific research
programs, and (ii) such duties and responsibilities as may be assigned to him
from time to time by the President & CEO, or Chief Scientific Officer (at such
time as a Chief Scientific Officer is appointed). The Employee shall perform
such duties and responsibilities at the Company's facility located in
Gaithersburg, Maryland, the anticipated facility in Germantown, Maryland, or at
such other location as may be mutually agreed upon by the Company and the
Employee in accordance with the business needs of the Company. The Employee, as
Vice President, shall report to the President & CEO, until such time as a Chief
Scientific Officer is appointed.

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                  3.       OTHER BUSINESS ACTIVITIES. Except with the prior
written consent of the Company in its sole discretion, the Employee shall not
engage, directly or indirectly, during the Term, in any other business
activities or pursuits whatsoever, except activities in connection with
charitable or civic activities, personal investments and serving as an executor,
trustee or in other similar fiduciary capacity; provided that any such
activities do not interfere with the performance of his responsibilities and
obligations pursuant to this Agreement.

                  4.       COMPENSATION. The Company shall pay the Employee, and
the Employee hereby agrees to accept, as compensation for all services to be
rendered to the Company and for the Employee's intellectual property covenants
and assignments and covenant not to compete, as provided in Sections 6 and 7
hereof, the compensation set forth in this Section 4.

                           4.1      Salary. The Company shall pay the Employee a
base salary at the annual rate of One Hundred Seventy Thousand Dollars
($170,000.00) (as the same may hereafter be adjusted, the "Salary") during the
Term of this Agreement. The Salary shall be inclusive of all applicable income,
social security and other taxes and charges that are required by law to be
withheld by the Company (collectively, "Taxes") and shall be paid and withheld
in accordance with the Company's normal payroll practice for its executive
employees from time to time in effect. The Salary shall be subject to increase
at the option and in the sole discretion of the Company based upon the
demonstrated performance of the Employee.

                           4.2      Bonus. Upon the execution of this Agreement,
the Employee shall be eligible to be awarded an annual cash bonus, which bonus
shall be determined by the President & CEO and the Board of Directors and shall
be in an amount up to twenty-five percent (25%) of Salary paid during such
applicable period, less Taxes, provided that the Employee shall have achieved
all of his performance objectives established for such period. Such bonus shall
be determined and paid within ninety (90) days after the conclusion of such
year.

                           4.3      Fringe Benefits. The Employee shall be
entitled to participate in the following programs and receive the following
benefits (collectively, the "Benefits") in accordance with the following
provisions.

                                    (a)      The Employee shall be entitled to
participate in any retirement, health or dental programs generally made
available to executive employees of the Company.

                                    (b)      The Employee shall be entitled to
participate in all vacation, life and disability insurance and other fringe
benefit programs of the Company to the extent and on the same terms and
conditions as are accorded to other executive employees of the Company.

                           4.4      Reimbursement of Expenses. During the Term,
the Employee shall be reimbursed for items of travel, food and lodging and
miscellaneous expenses reasonably incurred by him on behalf of the Company,
provided that such expenses are incurred,

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 2 of 14

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documented and submitted to the Company, all in accordance with the
reimbursement policies of the Company as in effect from time to time.

                  5.       CONFIDENTIALITY. The Employee recognizes and
acknowledges that the Proprietary Information (as hereinafter defined) is a
valuable, special and unique asset of the Company. As a result, both during the
Term and thereafter, the Employee shall not, without the prior written consent
of the Company, for any reason either directly or indirectly divulge to any
third-party or use for his own benefit, or for any purpose other than the
exclusive benefit of the Company, any confidential, proprietary, business and
technical information or trade secrets of the Company or of any subsidiary or
affiliate of the Company (the "Proprietary Information") revealed, obtained or
developed in the course of his employment with the Company. Proprietary
Information shall include any confidential or proprietary information or trade
secrets relating to any patents or other intellectual property assigned by the
Employee to the Company, including the patent applications identified in
Schedule I to the Stock Restriction Agreement between the Company and the
Employee of even date herewith. Proprietary Information also shall include, but
shall not be limited to the intangible personal property described in Section
6(b) hereof and, in addition, technical information, including research design,
results, techniques and processes; apparatus and equipment design; computer
software; technical management information, including project proposals,
research plans, status reports, performance objectives and criteria, and
analyses of areas for business development; and business information, including
project, financial, accounting and personnel information, business strategies,
plans and forecasts, customer lists, customer information and sales and
marketing plans, efforts, information and data. In addition, "Proprietary
Information" shall include all information and materials received by the Company
or Employee from a third party subject to an obligation of confidentiality
and/or non-disclosure. Nothing contained herein shall restrict the Employee's
ability to make such disclosures during the course of his employment as may be
necessary or appropriate to the effective and efficient discharge of the duties
required by or appropriate for the Position or as such disclosures may be
required by law. Furthermore, nothing contained herein shall restrict the
Employee from divulging or using for his own benefit or for any other purpose
any Proprietary Information that is readily available to the general public so
long as such information did not become available to the general public as a
direct or indirect result of the Employee's breach of this Section 5. Failure by
the Company to mark any of the Proprietary Information as confidential or
proprietary shall not affect its status as Proprietary Information under the
terms of this Agreement.

                  6.       PROPERTY.

                           6.1      Removal and Distribution. All right, title
and interest in and to Proprietary Information shall be and remain the sole and
exclusive property of the Company. During the Term, the Employee shall not
remove from the Company's offices or premises any documents, records, notebooks,
files, correspondence, reports, memoranda or similar materials of or containing
Proprietary Information, or other materials or property of any kind belonging to
the Company, unless necessary or appropriate in accordance with the duties and
responsibilities required by or appropriate for the Position and, in the event
that such materials or property are removed, all of the foregoing shall be
returned to their proper files or places of safekeeping as

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 3 of 14

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promptly as possible after the removal shall serve its specific purpose. The
Employee shall not make, retain, remove and/or distribute any copies of any of
the foregoing for any reason whatsoever, except as may be necessary in the
discharge of the assigned duties and shall not divulge to any third person the
nature of and/or contents of any of the foregoing or of any other oral or
written information to which he may have access or with which for any reason he
may become familiar, except as disclosure shall be necessary in the performance
of the duties; and upon the termination of his employment with the Company, the
Employee shall return to the Company all originals and copies of the foregoing
then in his possession or under his control, whether prepared by the Employee or
by others.

                           6.2      Developments.

                                    (a)      The Employee acknowledges that all
right, title and interest in and to any and all writings, documents, inventions,
discoveries, ideas, developments, information, computer programs or instructions
(whether in source code, object code, or any other form), algorithms, formulae,
plans, memoranda, tests, research, designs, innovations, systems, analyses,
specifications, models, data, diagrams, flow charts, and/or techniques (whether
patentable or non-patentable or whether reduced to written or electronic form or
otherwise) that the Employee creates, makes, conceives, discovers or develops,
either solely or jointly with any other person, at any time during the Term,
whether during working hours or at the Company's facility or at any other time
or location, and whether upon the request or suggestion of the Company or
otherwise, (collectively, "Intellectual Work Product") shall be the sole and
exclusive property of the Company. The Employee shall promptly disclose to the
Company all Intellectual Work Product, and the Employee shall have no claim for
additional compensation for the Intellectual Work Product, except for any
excluded Intellectual Work Product that is wholly unrelated to the
pharmaceutical industry, in the broadest sense, provided that such Intellectual
Work Product is not conceived, discovered or developed, either solely or jointly
with any other person during working hours or at the Company's facility or using
any other Company resource.

                                    (b)      The Employee acknowledges that all
the Intellectual Work Product that is copyrightable shall be considered a work
made for hire under United States Copyright Law. To the extent that any
copyrightable Intellectual Work Product may not be considered a work made for
hire under the applicable provisions of the United States Copyright Law, or to
the extent that, notwithstanding the foregoing provisions, the Employee may
retain an interest in any Intellectual Work Product, the Employee hereby
irrevocably assigns and transfers to the Company any and all right, title, or
interest that the Employee may have in the Intellectual Work Product under
copyright, patent, trade secret and trademark law, in perpetuity or for the
longest period otherwise permitted by law, without the necessity of further
consideration. The Company shall be entitled to obtain and hold in its own name
all copyrights, patents, trade secrets, and trademarks with respect thereto.

                                    (c)      The Employee shall reveal promptly
all information relating to any such Intellectual Property to the Board of
Directors of the Company, and, at the Company's expense, shall cooperate with
the Company and execute such documents as may be necessary or appropriate (i) in
the event that the Company desires to seek copyright, patent or

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 4 of 14

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trademark protection, or other analogous protection, thereafter relating to the
Intellectual Work Product, and when such protection is obtained, renew and
restore the same, or (ii) to defend any opposition proceedings in respect of
obtaining and maintaining such copyright, patent or trademark protection, or
other analogous protection.

                                    (d)      In the event the Company is unable
after reasonable effort to secure the Employee's signature on any of the
documents referenced in Section 6.2 (c) hereof, whether because of the
Employee's physical or mental incapacity or for any other reason whatsoever, the
Employee hereby irrevocably designates and appoints the Company and its duly
authorized officers and agents as the Employee's agent and attorney-in-fact, to
act for and on the behalf and stead to execute and file any such documents and
to do all other lawfully permitted acts to further the prosecution and issuance
of any such copyright, patent or trademark protection, or other analogous
protection, with the same legal force and effect as if executed by the Employee.

                                    (e)      The Employee represents that the
innovations, designs, systems, analyses, ideas, and all copyrights, patents,
trademarks and trade names, or similar intangible personal property
(collectively, the "Pre-existing Property") identified on Schedule I hereof
comprise all of the innovations, designs, systems, analyses, ideas and all
copyrights, patents, trademarks and trade names, or similar intangible personal
property that the Employee has made or conceived of prior to the date hereof,
and same are excluded from the operation of the other provisions of this Section
6.2. In the event that the Employee learns of any Pre-existing Property that he
inadvertently failed to include in Schedule I, and the circumstances surrounding
the failure of such inclusion are reasonably satisfactory to the Company, the
Employee and the Company shall jointly amend Schedule I to include such
property.

                  7.       COVENANT NOT TO COMPETE.

                           7.1      Restrictions. Provided that the Company is
in compliance with Section 8.4 hereof, if applicable, the Employee shall not,
during the Term and for a period of two (2) years thereafter (the "Restricted
Period"), except as an employee of the Company and in order to carry out the
Employee's duties hereunder, do any of the following directly or indirectly
without the prior written consent of the Company in its sole discretion:

                                    (a)      engage or participate, directly or
indirectly, in any business activity competitive with the Business or the
business of the Company or any of the Company's subsidiaries or affiliates as
conducted during the Term;

                                    (b)      become interested (as owner,
stockholder, lender, partner, co-venturer, director, officer, employee, agent,
consultant or otherwise) in any person, firm, corporation, association or other
entity engaged in any business that is competitive with the Business or of the
business of the Company or any subsidiary or affiliate of the Company as
conducted during the Term, or become interested in (as owner, stockholder,
lender, partner, co-venturer, director, officer, employee, agent, consultant or
otherwise) any portion of the business of any person, firm, corporation,
association or other entity where such portion of such

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 5 of 14

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business is competitive with the Business of the Company or the business of any
subsidiary or affiliate of the Company as conducted during the Term
(notwithstanding the foregoing, the Employee may hold not more than one percent
(1%) of the outstanding securities of any class of any publicly-traded
securities of a company that is engaged in activities referenced in this Section
7.1.

                                    (c)      solicit, call on or transact or
engage in any business activity with, either directly or indirectly, any (i)
customer with whom the Company shall have dealt at any time during the one (1)
year period immediately preceding the termination of the Employee's employment
hereunder, or (ii) corporate partner, collaborator, independent contractor or
supplier with whom the Company shall have dealt at any time during the one (1)
year period immediately preceding the termination of the Employee's employment
hereunder;

                                    (d)      influence or attempt to influence
any then current or prospective supplier, customer, corporate partner,
collaborator, or independent contractor of the Company to terminate or modify
any written or oral agreement or course of dealing with the Company; or

                                    (e)      influence or attempt to influence
any person either (i) to terminate or modify an employment, consulting, agency,
distributorship or other arrangement with the Company, or (ii) to employ or
retain, or arrange to have any other person or entity employ or retain, any
person who has been employed or retained by the Company as an employee,
consultant, agent or distributor of the Company at any time during the one (1)
year period immediately preceding the termination of the Employee's employment
hereunder.

                           7.2      Acknowledgment. The Employee acknowledges
that he has carefully read and considered the provisions of this Section 7. The
Employee acknowledges that the foregoing restrictions will limit his ability to
earn a livelihood in a business competitive with the Business, but he
nevertheless believes that he has received and will receive sufficient
consideration and other benefits in connection with the payment by the Company
of the compensation set forth in Sections 4 and 8.4 to justify such
restrictions, which restrictions the Employee does not believe would prevent him
from earning a living in businesses that are not competitive with the Business
and without otherwise violating the restrictions set forth herein.

                           8.       EARLY TERMINATION. The Employee's employment
hereunder may be terminated during the Term upon the occurrence of any one of
the events described in this Section 8. Upon termination, the Employee shall be
entitled only to such compensation and benefits as described in this Section 8.

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 6 of 14

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                           8.1      Involuntary Termination.

                                    (a)     Termination for Disability.

                                             (i)      In the event of the
disability of the Employee such that the Employee is unable to perform the
duties and responsibilities hereunder to the full extent required by this
Agreement by reasons of illness, injury or incapacity for a period of more than
one hundred eighty (180) consecutive days or more than one hundred eighty (180)
days, in the aggregate, during any three hundred sixty-five (365) day period
("Disability"), the Company shall have the right to terminate Employee's
employment hereunder by written notice to the Employee.

                                             (ii)     In the event of a
termination of the Employee's employment hereunder pursuant to Section
8.1(a)(i), the Employee will be entitled to receive all accrued and unpaid (as
of the date of such termination) Salary and applicable Benefits; provided that
the Employee has complied with all of his obligations under this Agreement and
continues to comply with all of his surviving obligations hereunder listed in
Section 10 and a pro-rata percentage of the bonus (provided in Section 4.2) for
the last fiscal year of the Company prior to the date of Employee's termination.
Except as specifically set forth in this Section 8.1(a)(ii) or as provided by
applicable law, the Company shall have no liability or obligation to the
Employee for compensation or benefits hereunder by reason of, or subsequent to,
such termination.

                                    (b)      Termination by Death. In the event
that the Employee dies during the Term, the Employee's employment hereunder
shall be terminated thereby and the Company shall pay to the Employee's
executors, legal representatives or administrators an amount equal to the
accrued and unpaid portion of the Salary for the month in which he dies and a
pro-rata percentage of the bonus (provided in Section 4.2) for the last fiscal
year of the Company prior to the date of Employee's termination. Except as
specifically set forth in this Section 8.1(b) or as provided by applicable law,
the Company shall have no liability or obligation hereunder to the Employee's
executors, legal representatives, administrators, heirs or assigns or any other
person claiming under or through him by reason of or subsequent to the
Employee's death.

                           8.2      Termination for Cause.

                                    (a)      The Company shall have the right to
terminate the Employee's employment hereunder at any time for "cause" upon
written notice to the Employee. For purposes of this Agreement, "cause" shall
mean the Employee's (including, if the Employee is not a natural person, any
employee of or contractor to the Employee who is involved, directly or
indirectly, in the provision of services to the Corporation) (a) dishonesty,
embezzlement, theft or fraudulent misconduct; (b) abuse of a controlled
substance that materially impairs the performance of the Employee's duties to
the Corporation; (c) conduct adverse to the business, interests, or reputation
of the Corporation; (d) material breach of any of the terms hereof or of any
agreement between the Corporation and the Employee, (including, but not limited
to, terms relating to non-disclosure, non-competition and invention assignment)
which, if curable, remains

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 7 of 14

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uncured thirty (30) days after the Employee receives written notice of such
breach; or (e) commission of a felony.

                                    (b)      In the event of a termination of
the Employee's employment hereunder pursuant to Section 8.2(a), the Employee
shall be entitled to receive all accrued but unpaid (as of the effective date of
such termination) Salary and Benefits. All Salary and Benefits shall cease at
the time of such termination, subject to the requirements of applicable law.
Except as specifically set forth in this Section 8.2, the Company shall have no
liability or obligation hereunder by reason of or subsequent to such
termination.

                           8.3      Termination by the Company Without Cause.

                                    (a)      Notwithstanding anything to the
contrary set forth herein, the Company shall have the right to terminate the
Employee's employment hereunder at any time, for any reason or no reason, with
or without cause, effective upon the date designated by the Company upon written
notice to the Employee.

                                    (b)      In the event of a termination of
the Employee's employment hereunder pursuant to Section 8.3(a), the Employee
shall be entitled to receive all accrued but unpaid (as of the effective date of
such termination) Salary; a pro-rata percentage of the bonus (provided in
Section 4.2) for the last fiscal year of the Company prior to the date of the
Employee's termination; and the severance payments and Benefits in the manner
set forth in Section 8.4; provided that the Employee has complied with all of
his obligations under this Agreement and continues to comply with all of his
surviving obligations hereunder listed in Section 10. All Salary shall cease at
the time of such termination, except as required under applicable law. Except as
specifically set forth in this Section 8.3, the Company shall have no liability
or obligation hereunder by reason of or subsequent to such termination.

                           8.4      Severance.

                                    (a)      In the event of the termination of
the Employee's employment under Section 8.3 the Employee shall be entitled to
severance pay in an amount equal to twenty-four (24) months of Salary, subject
to all withholding obligations, calculated on the basis of the Salary in effect
at the date of termination and paid in the same manner as Salary was then paid
hereunder.

                                    (b)      The Employee shall be entitled to
receive all Benefits to which he was entitled on the date preceding his
termination for the period of time during which he is entitled to receive
severance pay hereunder.

                                    (c)      Except as provided in subsections
(a) and (b) above, the Company shall have no liability or obligation by reason
of or subsequent to the termination of the employment relationship between the
Company and the Employee.

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 8 of 14

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                  9.       REPRESENTATIONS, WARRANTIES AND COVENANTS OF THE
EMPLOYEE.

                           9.1      Restrictions. The Employee represents and
warrants to the Company that:

                                    (a)      There are no restrictions,
agreements or understandings whatsoever to which the Employee is a party which
would prevent or make unlawful the Employee's execution of this Agreement or the
Employee's employment hereunder, or which is or would be inconsistent or in
conflict with this Agreement or the Employee's employment hereunder, or, except
as set forth in any agreements previously provided to the Company, would
prevent, limit or impair in any way the performance by the Employee of the
obligations hereunder; and

                                    (b)      The Employee has disclosed to the
Company all restraints, confidentiality commitments or other employment
restrictions that he has with any other employer, person or entity.

                           9.2      Obligations to Former Employers. The
Employee covenants that in connection with his provision of services to the
Company, he shall not breach any obligation (legal, statutory, contractual or
otherwise) to any former employer or other person, including, but not limited to
obligations relating to confidentiality and proprietary rights.

                           9.3      Obligations Upon Termination. Upon and after
his termination or cessation of employment with the Company and until such time
as no obligations of the Employee to the Company hereunder exist, the Employee
(i) shall provide a complete copy of this Agreement to any prospective employer
or other person, entity or association engaged in the Business, with whom or
which the Employee proposes to be employed, affiliated, engaged, associated or
to establish any business or remunerative relationship prior to the commencement
thereof and (ii) shall notify the Company of the name and address of any such
person, entity or association prior to his employment, affiliation, engagement,
association or the establishment of any business or remunerative relationship.

                  10.      SURVIVAL OF PROVISIONS. The provisions of this
Agreement set forth in Sections 5, 6, 7, 8, 9, 10, 19 and 20 hereof shall
survive the termination of the Employee's employment hereunder.

                  11.      SUCCESSORS AND ASSIGNS. This Agreement shall inure to
the benefit of and be binding upon the Company and the Employee and their
respective successors, executors, administrators, heirs and/or assigns; provided
that neither party shall make any assignment of this Agreement or any interest
herein, by operation of law or otherwise, without the prior written consent of
the other party.

                  12.      NOTICE. Any notice hereunder by either party shall be
given by personal delivery or by sending such notice by certified mail,
return-receipt requested, or telecopied, addressed or telecopied, as the case
may be, to the other party at its address set forth below or at

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 9 of 14

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such other address designated by notice in the manner provided in this section.
Such notice shall be deemed to have been received upon the date of actual
delivery if personally delivered or, in the case of mailing, two (2) days after
deposit with the U.S. mail, or, in the case of facsimile transmission, when
confirmed by the facsimile machine report.

                           (a)      if to the Company, to:

                                    Advancis Pharmaceutical Corporation
                                    656 Quince Orchard Road, Suite 220
                                    Gaithersburg, MD 20878
                                    Attention: Human Resources
                                    Facsimile: (240) 683-9853

                                    with a copy to:

                                    Howard Schwartz, Esquire
                                    Piper Marbury Rudnick & Wolfe LLP
                                    6225 Smith Avenue
                                    Baltimore, Maryland   21209-3600
                                    Facsimile: (410) 580-3251

                           (b)      if to the Employee, to:

                                    Robert J. Guttendorf, Ph.D.
                                    12204 McDonald Chapel Drive
                                    Gaithersburg, MD 20878

                                    with a copy to:

                                    Howard Schwartz, Esquire
                                    Piper Rudnick & Wolfe LLP
                                    6225 Smith Avenue
                                    Baltimore, Maryland   21209-3600
                                    Facsimile: (410) 580-3251

                  13.      ENTIRE AGREEMENT; AMENDMENTS. This Agreement contains
the entire agreement and understanding of the parties hereto relating to the
subject matter hereof, and merges and supersedes all prior and contemporaneous
discussions, agreements and understandings of every nature between the parties
hereto relating to the employment of the Employee with the Company. This
Agreement may not be changed or modified, except by an agreement in writing
signed by each of the parties hereto.

                  14.      WAIVER. The waiver of the breach of any term or
provision of this Agreement shall not operate as or be construed to be a waiver
of any other or subsequent breach of this Agreement.

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 10 of 14

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                  15.      GOVERNING LAW. This Agreement shall be construed and
enforced in accordance with the laws of the State of Delaware, without regard to
the principles of conflicts of laws of any jurisdiction.

                  16.      INVALIDITY. If any provision of this Agreement shall
be determined to be void, invalid, unenforceable or illegal for any reason, the
validity and enforceability of all of the remaining provisions hereof shall not
be affected thereby. If any particular provision of this Agreement shall be
adjudicated to be invalid or unenforceable, such provision shall be deemed
amended to delete therefrom the portion thus adjudicated to be invalid or
unenforceable, such amendment to apply only to the operation of such provision
in the particular jurisdiction in which such adjudication is made; provided
that, if any provision contained in this Agreement shall be adjudicated to be
invalid or unenforceable because such provision is held to be excessively broad
as to duration, geographic scope, activity or subject, such provision shall be
deemed amended by limiting and reducing it so as to be valid and enforceable to
the maximum extent compatible with the applicable laws of such jurisdiction,
such amendment only to apply with respect to the operation of such provision in
the applicable jurisdiction in which the adjudication is made.

                  17.      SECTION HEADINGS. The section headings in this
Agreement are for convenience only; they form no part of this Agreement and
shall not affect its interpretation.

                  18.      NUMBER OF DAYS. In computing the number of days for
purposes of this Agreement, all days shall be counted, including Saturdays,
Sundays and legal holidays; provided that, if the final day of any time period
falls on a Saturday, Sunday or day which is a legal holiday in Delaware or
Maryland, then such final day shall be deemed to be the next day which is not a
Saturday, Sunday or legal holiday.

                  19.      SPECIFIC ENFORCEMENT The Employee acknowledges that
the restrictions contained in Sections 5, 6, and 7 hereof are reasonable and
necessary to protect the legitimate interests of the Company and its affiliates
and that the Company would not have entered into this Agreement in the absence
of such restrictions. The Employee also acknowledges that any breach by him of
Sections 5, 6, or 7 hereof will cause continuing and irreparable injury to the
Company for which monetary damages would not be an adequate remedy. The Employee
shall not, in any action or proceeding to enforce any of the provisions of this
Agreement, assert the claim or defense that an adequate remedy at law exists. In
the event of such breach by the Employee, the Company shall have the right to
enforce the provisions of Sections 5, 6, and 7 of this Agreement by seeking
injunctive or other relief in any court, and this Agreement shall not in any way
limit remedies of law or in equity otherwise available to the Company.

                  20.      CONSENT TO SUIT. Subject to the provisions of Section
21 hereof, any legal proceeding arising out of or relating to this Agreement
shall be instituted in the Court of Chancery of New Castle County, or if such
court does not have jurisdiction or will not accept jurisdiction, in any state
or federal court of general jurisdiction in the State of Delaware, and each of
the Company and the Employee hereby consents to the personal and exclusive
jurisdiction of such court and hereby waives any objection that either party may
have to the laying of venue of

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 11 of 14

<PAGE>

any such proceeding and any claim or defense of inconvenient forum. If an action
at law or in equity is necessary to enforce or interpret the terms of this
Agreement, the prevailing party shall be entitled to recover, in addition to any
other relief, reasonable attorneys' fees, costs and disbursements.

                  21.      ARBITRATION. Subject to the last sentence of this
Section 21, if any dispute arises over the terms of this Agreement between the
parties to this Agreement, either Employee or Company may submit the dispute to
binding arbitration within thirty (30) days after such dispute arises, to be
governed by the evidentiary and procedural rules of the American Arbitration
Association (Commercial Arbitration). Employee and Company shall mutually select
one (1) arbitrator within ten (10) days after a dispute is submitted to
arbitration. In the event that the parties do not agree on the identity of the
arbitrator within such period, the arbitrator shall be selected by the American
Arbitration Association. The arbitrator shall hold a hearing on the dispute in
Wilmington, Delaware within thirty (30) days after having been selected and
shall issue a written opinion within fifteen (15) days after the hearing. The
arbitrator shall also decide on the allocation of the costs of the arbitration
to the respective parties, but Employee and Company shall each be responsible
for paying the fees of their own legal counsel, if legal counsel is obtained.
Either Employee or Company, or both parties, may file the decision of the
arbitrator as a final, binding and unappealable judgment in a court of
appropriate jurisdiction. Notwithstanding the foregoing provisions of this
Section 21 to the contrary, matters in which an equitable remedy or injunctive
relief is sought by a party, including but not limited to the remedies referred
to in Section 19 hereof, shall not be required to be submitted to arbitration,
if the party seeking such remedy or relief objects thereto, but shall instead be
subject to the provisions of Sections 19 and 20 hereof.

                  22.      COUNTERPARTS. This Agreement may be executed in one
or more counterparts, each of which shall be deemed an original, and all of
which together shall be deemed to be one and the same instrument.

                  23.      AUTHORIZATION. In connection with the execution of
this Agreement, the Employee shall be provided with a copy of the resolutions of
the Board of Directors of the Company authorizing the execution of this
Agreement on behalf of the Company.

                         [SIGNATURES ON FOLLOWING PAGE]

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 12 of 14

<PAGE>

                  IN WITNESS WHEREOF, the parties have caused this Executive
Employment Agreement to be executed the day and year first written above.

                             ADVANCIS PHARMACEUTICAL CORPORATION

                             By: /s/ Edward M. Rudnic
                                ---------------------------------
                                Edward M. Rudnic, Ph.D.
                                President & CEO

                                 /s/ Robert J. Guttendorf
                                ----------------------------------
                                Robert J. Guttendorf, Ph.D.

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 13 of 14

<PAGE>

SCHEDULE I

Preexisting Property:

Employee Name: Robert J. Guttendorf, Ph.D.     Employment Agreement Ver. 01/2003
Dated January 3, 2003                          Page 14 of 14