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                                                                   EXHIBIT 10.12

[AMICUS THERAPEUTICS LOGO]


February 2, 2006

Dr. Karin Ludwig
174 Washington Street, #4H
Jersey City, NJ 07302

Dear Karin:

      On behalf of Amicus Therapeutics, Inc. (the "Company"), I am pleased to
confirm our offer to you for the position of Sr. Vice President, Clinical
Research reporting to me. Your start date will be mutually agreed upon but no
later then February 21, 2006.

      Prior to the commencement of your employment you will be required to
execute the Company's Confidentiality, Disclosure and Non-Competition Agreement.
A copy of this agreement is attached. In addition, as a condition of employment
Amicus requires a pre-employment drug screening.

      In consideration for all your services to be rendered to the Company your
annual base salary will be $235,000, to be paid bi-weekly in accordance with the
Company's payroll practices. Upon the completion of mutually agreed upon
individual goals and objectives as well as the achievement of specific Company
goals, you will be eligible to receive a year end bonus target of 25% of your
base salary, minus customary deductions. Once you agree to join Amicus, payable
with your first paycheck, you will receive a sign on bonus of $60,000 minus
customary deductions.

      Upon approval by the Board of Directors, you will receive an incentive
stock option to purchase 450,000 shares of the Company's common stock, par value
$.01 per share (the "Common Stock") pursuant to a stock option agreement in form
and substance acceptable to the Company. The options will become exercisable
over a four-year period as follows: 25% on the first anniversary of the date of
grant, and the remaining 75% in equal monthly increments thereafter. The
exercise price of the options will be the fair market value of the Company's
common stock on the date of grant. Shares issuable upon exercise of each option
will be subject to certain transfer restrictions including the right of first
refusal. Additionally, exercise of the options will be governed in accordance
with the provisions of the Company's stock option plan.

      You will be eligible to participate in the Company's health benefits
program and are eligible to participate in the Company's 401(k) as well as any
other employee benefit plan(s) that are generally made available by the Company
to its employees from time to time when and as the Company may make them
available. You will be eligible for paid Company holidays as outlined in our
Holiday Policy and you will be eligible for twenty

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6 Cedar Brook Drive   Cranbury, NJ 08512   T: 609-662-2000   F: 609-662-2001   www.amicustherapeutics.com
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Dr. Karin Ludwig
February 2, 2006
Page #2 of 3

(20) days paid vacation, three weeks during the year and one between Christmas
and New Years. Vacation accrues on a monthly basis. Because the Company expects
to regularly review its benefit programs to keep them up to date and
competitive, these programs are subject to periodic adjustments so that certain
features may be added, modified or deleted over time.

      If you are terminated without Cause, you will be eligible for a
continuation of six (6)month salary, an additional six (6) months of option
vesting, plus payment of a bonus payment equal to the bonus earned in the
preceding year. "Cause" means for any of the following reasons: (i) willful or
deliberate misconduct by you that materially damages the company; (ii)
misappropriation of company assets; (iii) conviction of or a plea of guilty or
"no contest" to, a felony; or (iv) any willful disobedience of the lawful and
unambiguous instructions of the CEO of the company; provided that the CEO has
given you written notice of such disobedience or neglect and you have failed to
cure such disobedience or neglect within a period reasonable under the
circumstances.

      If there is a Change in Control Event and you resign for Good Reason or
are terminated without Cause within six months of such Change in Control Event,
then (i) you will be entitled to receive a continuation of twelve (12) months
salary, plus payment of a bonus payment equal to the bonus earned in the
preceding year and (ii) all unvested stock options will have their remaining
vesting schedule accelerated so that all stock options are fully vested.

      "Change in Control Event" means any of the following: (i) any person or
entity (except for a current stockholder) becomes the beneficial owner of
greater than 50% of the then outstanding voting power of the company; (ii) a
merger or consolidation with another entity where the voting securities of the
company outstanding immediately before the transaction constitute less than a
majority of the voting power of the voting securities of the company or the
surviving entity outstanding immediately after the transaction, or (iii) the
sales or disposition of all or substantially all of the company's assets. "Good
Reason" means (i) a change in your position with the company or its successor
that materially reduces your title, duties or level of responsibility; or (ii)
the relocation of the company or its successor greater than 50 miles away from
the then current location of the company's principal offices.

      Your right to receive accelerated vesting and severance payments pursuant
to the preceding three paragraphs shall be subject to the condition that you
execute a full release and waiver of all claims against the company and related
parties, in a form acceptable to the company.

      There is a two (2) year term on this agreement that will automatically
renew unless either party provides a thirty (30) day notice of termination.

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Dr. Karin Ludwig
February 2, 2006
Page # 3 of 3

      In accordance with the Immigration and Naturalization Control Act, all new
employees must provide documentation that they have the legal right to work in
the United States. A copy of Form I-9 and a list of the acceptable documents
confirming Your right to work in the United States are also attached for your
convenience.

      To indicate your acceptance of our offer, please sign one copy of this
letter in the space indicated below and return it to the attention of Nicole
Schaeffer, Vice President, Human Resources & Leadership Development on or before
February 8, 2006. Acceptance of this offer constitutes your agreement with all
of the above terms and conditions of employment with Amicus Therapeutics, Inc.,
and constitutes agreement to conform to Amicus Therapeutics, Inc. rules and
procedures. By signing below, you agree that no other promises, express or
implied, have been made to you either verbally or in writing and that no further
modifications to these terms and conditions will be effective except by a
written agreement signed by the Chief Executive Officer of the Company and you.

      The formality of this letter not withstanding, I extend my personal best
wishes and sincere pleasure that you are joining our team. I look forward to
working with you.

Sincerely,

/s/ John F. Crowley
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John F. Crowley
Chairman & CEO

I accept the offer of employment under the terms and conditions stated above. No
other promises express or implied, have been made to me either verbally or in
writing.

By: /s/ Karin Ludwig                             Date: 2/6/2006
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      Karin Ludwig