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                                                                     EXHIBIT 4.1


                      RESTATED CERTIFICATE OF INCORPORATION
                                       OF
                            AMICUS THERAPEUTICS, INC.

     Incorporated pursuant to a Certificate of Incorporation initially filed
    with the Secretary of State of the State of Delaware on February 4, 2002
                    Under the Name Amicus Therapeutics, Inc.


         Amicus Therapeutics, Inc., a Delaware corporation (the "Corporation"),
hereby certifies that this Restated Certificate of Incorporation has been duly
adopted in accordance with the provisions of Sections 228, 242, and 245 of the
General Corporation Law of the State of Delaware (the "DGCL"), and notice
thereof has been given in accordance with the provisions of Section 228 of the
DGCL:

         FIRST:   The name of the Corporation is Amicus Therapeutics, Inc.

         SECOND:  The address of the Corporation's registered office in the
State of Delaware is c/o Corporation Trust Center, 1209 Orange Street,
Wilmington, New Castle County, Delaware 19801. The registered agent in charge
thereof is The Corporation Trust Company.

         THIRD:   The nature of the business and purposes to be conducted or
promoted by the Corporation are as follows:

         To engage in any lawful act or activity for which corporations may be
         organized under the General Corporation Law of the State of Delaware.

         FOURTH:  The total number of shares of all classes of capital stock
         which the Corporation shall have authority to issue is Sixty Million
         shares, consisting solely of:

         Fifty Million (50,000,000) shares of common stock, par value $.01 per
         share ("Common Stock"); and

         Ten Million (10,000,000) shares of preferred stock, par value $.01 per
         share ("Preferred Stock").

         The following is a statement of the powers, designations, preferences,
privileges, and relative rights in respect of each class of capital stock of the
Corporation.

         A.       COMMON STOCK.

         1.       General. The voting, dividend and liquidation rights of the
holders of Common Stock are subject to and qualified by the rights of the
holders of Preferred Stock.

         2.       Voting. The holders of Common Stock are entitled to one vote
for each share held at all meetings of stockholders. There shall be no
cumulative voting.


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         3.       Dividends. Dividends may be declared and paid on the Common
Stock from funds lawfully available therefor if, as and when determined by the
board of directors of the Corporation (the "Board of Directors") and subject to
any preferential dividend rights of any then outstanding shares of Preferred
Stock.

         4.       Liquidation. Upon the dissolution or liquidation of the
Corporation, whether voluntary or involuntary, holders of Common Stock will be
entitled to receive all assets of the Corporation available for distribution to
its stockholders, subject to any preferential rights of any then outstanding
shares of Preferred Stock.

         B.       PREFERRED STOCK.

         Shares of Preferred Stock may be issued from time to time in one or
more series, each of such series to have such powers, designations, preferences,
and relative, participating, optional, or other special rights, if any, and such
qualifications and restrictions, if any, of such preferences and rights, as are
stated or expressed in the resolution or resolutions of the Board of Directors
providing for such series of Preferred Stock. Different series of Preferred
Stock shall not be construed to constitute different classes of shares for the
purposes of voting by classes unless expressly so provided in such resolution or
resolutions.

         Authority is hereby granted to the Board of Directors from time to time
to issue the Preferred Stock in one or more series, and in connection with the
creation of any such series, by resolution or resolutions to determine and fix
the powers, designations, preferences, and relative, participating, optional, or
other special rights, if any, and the qualifications and restrictions, if any,
of such preferences and rights, including without limitation dividend rights,
conversion rights, voting rights (if any), redemption privileges, and
liquidation preferences, of such series of Preferred Stock (which need not be
uniform among series), all to the fullest extent now or hereafter permitted by
the DGCL. Without limiting the generality of the foregoing, the resolution or
resolutions providing for the creation or issuance of any series of Preferred
Stock may provide that such series shall be superior to, rank equally with, or
be junior to the Preferred Stock of any other series, all to the fullest extent
permitted by law. No resolution, vote, or consent of the holders of the capital
stock of the Corporation shall be required in connection with the creation or
issuance of any shares of any series of Preferred Stock authorized by and
complying with the conditions of this Restated Certificate of Incorporation, the
right to any such resolution, vote, or consent being expressly waived by all
present and future holders of the capital stock of the Corporation.

         Any resolution or resolutions adopted by the Board of Directors
pursuant to the authority vested in them by this Article Fourth shall be set
forth in a certificate of designation along with the number of shares of stock
of such series as to which the resolution or resolutions shall apply and such
certificate shall be executed, acknowledged, filed, recorded, and shall become
effective, in accordance with Section 103 of the DGCL. Unless otherwise provided
in any such resolution or resolutions, the number of shares of stock of any such
series to which such resolution or resolutions apply may be increased (but not
above the total number of authorized shares of the class) or decreased (but not
below the number of shares thereof then outstanding) by a certificate likewise
executed, acknowledged, filed and recorded, setting forth a statement that a
specified increase or decrease therein has been authorized and directed by a
resolution or resolutions likewise adopted by the Board of Directors. In case
the number of such shares shall be decreased, the number of shares so specified
in the certificate shall resume the status which they had prior to the adoption
of the first resolution or resolutions. When no shares of any such class or
series are outstanding, either because none were issued or because none remain
outstanding, a certificate setting forth a


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resolution or resolutions adopted by the Board of Directors that none of the
authorized shares of such class or series are outstanding, and that none will be
issued subject to the certificate of designations previously filed with respect
to such class or series, may be executed, acknowledged, filed and recorded in
the same manner as previously described and it shall have the effect of
eliminating from the Restate Certificate of Incorporation all matters set forth
in the certificate of designations with respect to such class or series of
stock. If no shares of any such class or series established by a resolution or
resolutions adopted by the Board of Directors have been issued, the voting
powers, designations, preferences and relative, participating, optional or other
rights, if any, with the qualifications, limitations or restrictions thereof,
may be amended by a resolution or resolutions adopted by the Board of Directors.
In the event of any such amendment, a certificate which (i) states that no
shares of such class or series have been issued, (ii) sets forth the copy of the
amending resolution or resolutions and (iii) if the designation of such class or
series is being changed, indicates the original designation and the new
designation, shall be executed, acknowledged, filed, recorded, and shall become
effective, in accordance with Section 103 of the DGCL.

         FIFTH: The following provisions are inserted for the management of the
business and for the conduct of the affairs of the Corporation and for defining
and regulating the powers of the Corporation and its directors and stockholders
and are in furtherance and not in limitation of the powers conferred upon the
Corporation by statute:

                  (a) The Board of Directors shall be divided into three classes
         of directors, as determined by the Board of Directors, such classes to
         be as nearly equal in number of directors as possible, having staggered
         three-year terms of office, the term of office of the directors of the
         first such class to expire as of the first annual meeting of the
         Corporation's stockholders following the closing of the Corporation's
         first public offering of shares of Common Stock registered pursuant to
         the Securities Act of 1933, as amended, those of the second class to
         expire as of the second annual meeting of the Corporation's
         stockholders following such closing, and those of the third class as of
         the third annual meeting of the Corporation's stockholders following
         such closing, such that at each annual meeting of stockholders after
         such closing, nominees will stand for election to succeed those
         directors whose terms are to expire as of such meeting. Any director
         serving as such pursuant to this paragraph (a) of Article FIFTH may be
         removed only for cause and only by the vote of the holders of a
         majority of the shares of the Corporation's stock entitled to vote for
         the election of directors.

                  (b) Except as the DGCL or the Corporation's by-laws may
         otherwise require, in the interim between annual meetings of
         stockholders or special meetings of stockholders called for the
         election of directors and/or for the removal of one or more directors
         and for the filling of any vacancy in that connection, any vacancies in
         the Board of Directors, including unfilled vacancies resulting from the
         removal of directors for cause, may be filled by the vote of a majority
         of the remaining directors then in office, although less than a quorum,
         or by the sole remaining director.

                  (c) If the office of any director becomes vacant by reason of
         death, resignation, disqualification, removal, failure to elect, or
         otherwise, the remaining directors, although more or less than a
         quorum, by a majority vote of such remaining directors may elect a
         successor or successors who shall hold office for the unexpired term.


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                  (d) The Board of Directors shall have the power and authority:
         (i) to adopt, amend or repeal the Corporation's by-laws, subject only
         to such limitations, if any, as may be from time to time imposed by
         other provisions of this Restated Certificate of Incorporation, by law,
         or by the Corporation's by-laws; and (ii) to the full extent permitted
         or not prohibited by law, and without the consent of or other action by
         the stockholders, to authorize or create mortgages, pledges or other
         liens or encumbrances upon any or all of the assets, real, personal or
         mixed, and franchises of the Corporation, including after-acquired
         property, and to exercise all of the powers of the Corporation in
         connection therewith.

         SIXTH:   No director of the Corporation shall be personally liable to
the Corporation or to any of its stockholders for monetary damages for breach of
fiduciary duty as a director, notwithstanding any provision of law imposing such
liability; provided, however, that to the extent required from time to time by
applicable law, this Article Sixth shall not eliminate or limit the liability of
a director, to the extent such liability is provided by applicable law, (i) for
any breach of the director's duty of loyalty to the corporation or its
stockholders, (ii) for acts or omissions not in good faith or which involve
intentional misconduct or a knowing violation of law, (iii) under Section 174 of
the DGCL, or (iv) for any transactions from which the director derived an
improper personal benefit. No amendment to or repeal of this Article Sixth shall
apply to or have any effect on the liability or alleged liability of any
director for or with respect to any acts or omissions of such director occurring
prior to the effective date of such amendment or repeal.

         SEVENTH: The Corporation shall, to the fullest extent permitted by
Section 145 of the DGCL and as further provided in its by-laws, each as amended
from time to time, indemnify each person who was or is a party or is threatened
to be made a party to any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative or investigative, by reason
of the fact that he is or was, or has agreed to become, a director or officer of
the Corporation, or is or was serving, or has agreed to serve, at the request of
the Corporation, as a director, officer or trustee of, or in a similar capacity
with, another corporation, partnership, joint venture, trust or other enterprise
(including any employee benefit plan), or by reason of any action alleged to
have been taken or omitted in such capacity, against all expenses (including
attorneys' fees), judgements, fines and amounts paid in settlement actually and
reasonably incurred by him or on his behalf in connection with such action, suit
or proceeding and any appeal therefrom.

         Indemnification may include payment by the Corporation of expenses in
defending an action or proceeding in advance of the final disposition of such
action or proceeding upon receipt of an undertaking by the person indemnified to
repay such payment if it is ultimately determined that such person is not
entitled to indemnification under this Article Seventh, which undertaking may be
accepted without reference to the financial ability of such person to make such
repayment.

         The Corporation shall not indemnify any such person seeking
indemnification in connection with a proceeding (or part thereof) initiated by
such person unless the initiation thereof was approved by the Board of
Directors.

         The indemnification rights provided in this Article Seventh (i) shall
not be deemed exclusive of any other rights to which those indemnified may be
entitled under any law, agreement or vote of stockholders or disinterested
directors or otherwise, and (ii) shall inure to the benefit of the heirs,
executors and administrators of such persons. The Corporation may, to the extent
authorized from time to time by its Board of Directors, grant indemnification
rights to other


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employees or agents of the Corporation or other persons serving the Corporation
and such rights may be equivalent to, or greater or less than, those set forth
in this Article Seventh.

         EIGHTH:  Whenever a compromise or arrangement is proposed between the
Corporation and its creditors or any class of them and/or between the
Corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of the Corporation or of any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for the Corporation under the
provisions of Section 291 of the DGCL; or on the application of trustees in
dissolution or of any receiver or receivers appointed for the Corporation under
the provisions of Section 279 of the DGCL, order a meeting of the creditors or
class of creditors, and/or of the stockholders or class of stockholders of the
Corporation, as the case may be, to be summoned in such a manner as the said
court directs. If a majority of the number representing three-fourths (3/4ths)
in value of the creditors or class of creditors, and/or of the stockholders or
class of stockholders of the Corporation, as the case may be, agree to any
compromise or arrangement and to any reorganization of the Corporation as a
consequence of such compromise or arrangement, the compromise or arrangement and
the said reorganization shall, if sanctioned by the court to which the said
application has been made, be binding on all creditors or class of creditors,
and/or stockholders or class of stockholders of the Corporation, as the case may
be, and also on the Corporation.

         NINTH:   The Board of Directors, when considering a tender offer or
merger or acquisition proposal, may take into account factors in addition to
potential economic benefits to stockholders, including without limitation (i)
comparison of the proposed consideration to be received by stockholders in
relation to the then current market price of the Corporation's capital stock,
the estimated current value of the Corporation in a freely negotiated
transaction, and the estimated future value of the Corporation as an independent
entity and (ii) the impact of such a transaction on the employees, suppliers,
and customers of the Corporation and its effect on the communities in which the
Corporation operates.

         TENTH:   Any action required or permitted to be taken by the
stockholders of the Corporation may be taken only at a duly called annual or
special meeting of the stockholders, and not by written consent in lieu of such
a meeting, in which such action is properly brought before such meeting. Special
meetings of stockholders may be called only by the Chairman of the Board of
Directors, the President, or a majority of the Board of Directors.

         ELEVENTH: The affirmative vote of the holders of at least sixty seven
percent (67%) of the outstanding voting stock of the Corporation (in addition to
any separate class vote that may in the future be required pursuant to the terms
of any outstanding Preferred Stock) shall be required to amend or repeal the
provisions of Articles Fourth (only to the extent it relates to the authority of
the Board of Directors to issue shares of Preferred Stock in one or more series,
the terms of which may be determined by the Board of Directors), Fifth, Seventh,
Tenth, or Eleventh of this Restated Certificate of Incorporation or to reduce
the numbers of authorized shares of Common Stock or Preferred Stock.


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Executed on June 5, 2007


                                   AMICUS THERAPEUTICS, INC.

                                   By:    /s/ John F. Crowley
                                          ----------------------------------
                                   Name:  John F. Crowley
                                   Title: President and Chief Executive Officer