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                                                                   Exhibit 10.14

                              [ACTIVBIOTICS LOGO]

January 7, 2004

Andrew L. Sternlicht, MD
533 Hammond Street
Chestnut Hill, MA 02467

Dear Andrew,

I am pleased to offer you the position of VICE PRESIDENT, CLINICAL DEVELOPMENT
with ActivBiotics, Inc., with a start date of 3/8/04.

Your annual base salary will be $260,000 payable in bi-weekly installments of
$10,833.34. You will also be eligible for the company stock option program, with
an initial grant of 580,000 shares. This award is subject to the terms of the
option plan, including a vesting schedule of 25% per year for four years Andrew,
this award represents an important equity position in ActivBiotics, and we look
forward to working together to continue build the value of this company. You
will also participate in our bonus program, eligible to earn an additional 30%
of your annual base salary. This bonus payout will be determined by your
individual performance against agreed upon objectives, as well as company and
management team performance against objectives.

You will also be eligible for the following additional employee benefits:

-    Health and dental Insurance

-    Long and short term disability insurance and long term care insurance

-    8 fixed and 4 floating holidays

-    401K retirement plan

-    Direct deposit of payroll (OPTIONAL)

-    Section 125 plan, allowing pre-tax deduction of health and dental insurance
     contributions

-    4 weeks (20 days) paid vacation time per year.

-    An option to purchase shares of the Company's common stock in accordance
     with the Company's stock option plan. This award, including the strike
     price, is subject to the approval of the Company's Board of Directors.

     The Option will be subject to the terms and conditions of the Company's
Stock Option Plan (the "Plan"), and the Stock Option Agreement that you will
sign (the "Option Agreement"), which will include, among other things, a vesting
schedule stating that the Option will vest 25% on the anniversary of the date
you sign this letter, and then annually thereafter over a period of three years
from such anniversary, provided you remain employed with the Company on each
applicable vesting date. Please consult the Stock Option Agreement and the Plan
for further information, which are attached hereto. Any Additional Options will
be subject to their applicable option agreement and the option plan then in
effect.

Your employment with the Company will be on an "at-will" basis, which means that
either you or the Company may terminate the employment relationship at any time,
for any or no reason, with or without Cause, and with or without prior notice.
If your employment is terminated by ActivBiotics without Cause, you will be
eligible to receive 3 months salary continuation payments at your base salary
rate in effect as of your date of termination, paid in accordance with the
Company's payroll practice then in effect. The Company's obligation to pay any
salary continuation is conditioned upon the Company having received a general
release from you in a form and substance reasonable satisfactory to the Company

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     For purposes of this letter:

     "Cause" shall mean any one or more of the following: (i) your substantial
and continuing failure, for within a period of 30 days after receiving notice
thereof from the Board or the Chief Executive Officer of ActivBiotics, to
perform your responsibilities to the Company; (ii) your willful misconduct,
fraud, or material dishonesty that result in material harm to the Company; (iii)
your breach of fiduciary duty to the Company; (iv) your deliberate disregard of
the rules or policies of the Company or directions from the Board or the Chief
Executive Officer of ActivBiotics, which results in material harm to the
Company; (v) your commission of an act which constitutes unfair competition with
the Company or which induces any customer or supplier to breach a contract with
the Company; or (vi) your material breach of the invention and Non-Disclosure
agreement or any other agreement executed by you with the Company.

     Except as set forth in this or other applicable agreements, the Company
shall have no other obligations to you upon the cessation of your employment
other than payment of any accrued but unused vacation through the termination
date. All payments and benefits described herein will be subject to applicable
federal, state and local tax withholdings.

     The Company requires you to verify that the performance of the position at
ActivBiotics does not and will not breach any agreement entered into by you
prior to employment with the Company (i.e., you have not entered into any
agreements with previous employers that are in conflict with your obligations to
ActivBiotics.) Please provide us with a copy of any potentially conflicting
agreements for our review. You will also be required to sign the Company's
standard invention and Non-Disclosure agreement, which is enclosed, as a
condition of your employment with the Company.

Andrew, we are confident that you will make an important contribution to the
success of ActivBiotics, and look forward to working with you. This offer will
be valid until January 12, 2004 please do not hesitate to contact me if you have
any questions. In order to accept the position as offered, please sign this
letter and the attached application for employment for our records, and return
both to me.

Sincerely,                              I accept the offer of employment as
                                        outlined above,


/s/ Cathy Carew                         /s/ Andrew L. Sternlicht
-------------------------------------   ----------------------------------------
Cathy Carew,                            Andrew L. Sternlicht, MD
Vice President, Human Resources         Vice President, Clinical Development
                                        JANUARY 21, 2004