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                                                                     EXHIBIT 3.1


                              AMENDED AND RESTATED

                            ARTICLES OF INCORPORATION

                                       OF

                           PENWEST PHARMACEUTICALS CO.


        Pursuant to RCW 23B.10.070 of the Washington Business Corporation Act,
Edward Mendell Co., Inc., a Washington corporation, hereby amends and restates
its Articles of Incorporation as follows:

                                 ARTICLE 1. NAME

        The name of the corporation is Penwest Pharmaceuticals Co.

                               ARTICLE 2. PURPOSE

        The purpose of the corporation is to engage in any business, trade or
activity which may lawfully be conducted by a corporation organized under the
Washington Business Corporation Act.

                     ARTICLE 3. REGISTERED OFFICE AND AGENT

        The address of the registered office of the corporation is Two Union
Square, 601 Union Street, Seattle, Washington 98101, and the name of its
registered agent is Bogle & Co.

                                ARTICLE 4. SHARES

        The total number of shares of stock which the corporation has authority
to issue is 40,000,000 shares, consisting of 39,000,000 shares of common stock,
par value $0.001 per share, and 1,000,000 shares of preferred stock, par value
$0.001 per share.

        The preferred stock may be issued from time to time in one or more
series in any manner permitted by law and these Restated Articles of
Incorporation, as determined from time to time by the Board of Directors and
stated in the resolution or resolutions providing for the issuance thereof,
prior to the issuance of any shares thereof. The Board of Directors shall have
the authority to fix and determine and to amend, subject to the provisions
hereof, the designations, preferences, limitations and relative rights of the
shares of any series that is wholly unissued or to be established. Unless
otherwise provided in the resolution establishing any series, the Board of
Directors shall have the authority, after the issuance of shares of a series
whose number it has designated, to amend the resolution establishing such series
to decrease the number of shares of that series, but not below the number of
shares of such series then outstanding.








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                          ARTICLE 5. PREEMPTIVE RIGHTS

        No preemptive rights shall exist with respect to shares of stock or
securities convertible into shares of stock of the corporation.

                          ARTICLE 6. CUMULATIVE VOTING

        The right to cumulate votes in the election of directors shall not exist
with respect to shares of stock of the corporation.

                               ARTICLE 7. DURATION

        The period of the corporation's duration shall be perpetual.

                              ARTICLE 8. DIRECTORS

        The directors shall be divided into three classes, designated Class I,
Class II and Class III. Initially, Class I directors shall be elected for a term
ending at the first annual meeting of shareholders after their election, Class
II directors shall be elected for a term ending at the second annual meeting of
shareholders after their election, and Class III directors shall be elected for
a term ending at the third annual meeting of shareholders after their election.
At each annual meeting of shareholders thereafter, successors to the class of
directors whose term expires at that annual meeting shall be elected to serve
until the third succeeding annual meeting of shareholders. If the number of
directors is changed in the manner provided by the Bylaws, any increase or
decrease shall be apportioned among the classes so that the number of directors
in each class is as nearly equal as possible. A director shall hold office until
the annual meeting of shareholders at which such director's term expires and
until such director's successor shall be elected and shall qualify, subject,
however, to prior death, resignation, retirement, disqualification or removal
from office. Vacancies on the Board of Directors, including vacancies resulting
from an increase in the number of directors, may be filled only by the
affirmative vote of a majority of all the directors then in office (although
less than a quorum) or by the sole remaining director. The term of a director
elected to fill a vacancy shall expire at the next shareholders' meeting at
which directors are elected.

        A director may be removed only for cause by affirmative vote of the
holders of not less than two-thirds of the shares entitled to vote in the
election of such director.

                                ARTICLE 9. BYLAWS

        The Board of Directors shall have the power to adopt, amend or repeal
the Bylaws of the corporation. The shareholders shall also have the power to
adopt, amend or repeal the Bylaws of the corporation upon the affirmative vote
of the holders of not less than two-thirds of the shares entitled to vote
thereon.



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               ARTICLE 10. AMENDMENTS TO ARTICLES OF INCORPORATION

        The corporation reserves the right to amend or repeal these Restated
Articles of Incorporation in any manner permitted by law, and the rights of the
shareholders herein are granted subject to this reservation. Notwithstanding the
foregoing, the provisions set forth in Articles 6, 8, 9, 10, 12 and 13 may be
amended or repealed only upon the affirmative vote of the holders of not less
than two-thirds of the shares entitled to vote thereon.

                  ARTICLE 11. LIMITATION OF DIRECTOR LIABILITY

        To the fullest extent permitted by the Washington Business Corporation
Act as the same exists or may hereafter be amended, a director of the
corporation shall not be liable to the corporation or its shareholders for
monetary damages for conduct as a director. Any amendment to or repeal of this
Article 11 shall not adversely affect any right or protection of a director for
or with respect to any acts or omissions of such director occurring prior to
such amendment or repeal.

                   ARTICLE 12. SPECIAL SHAREHOLDERS' MEETINGS

        If the corporation is not a "Public Company" (as hereinafter defined),
then special meetings of the shareholders may be called at any time by the Board
of Directors, the Chairman of the Board of Directors or the President of the
corporation or by the holders of at least 25% of all the votes entitled to be
cast on any issue proposed to be considered at such special meeting in
accordance with RCW 23B.07.020. If the corporation is a Public Company, then
special meetings of the shareholders may be called by the Board of Directors,
the Chairman of the Board of Directors or the President of the corporation and
may not be called by any other person. "Public Company" means a corporation that
has a class of equity securities registered with the Securities and Exchange
Commission pursuant to Section 12 or 15 of the Securities Exchange Act of 1934,
as amended.

                     ARTICLE 13. SPECIAL VOTING REQUIREMENTS

        In addition to any affirmative vote required by law, by these Restated
Articles of Incorporation or otherwise, any "Business Combination" (as
hereinafter defined) involving the corporation shall be subject to approval in
the manner set forth in this Article 13.

        Section 13.1. DEFINITIONS. For the purposes of this Article:

                13.1.1. "Business Combination" means (i) a merger, share
exchange or consolidation of the corporation or any of its Subsidiaries with any
other corporation; (ii) the sale, lease, exchange, mortgage, pledge, transfer or
other disposition or encumbrance, whether in one transaction or a series of
transactions, by the corporation or any of its Subsidiaries of all or a
substantial part of the corporation's assets otherwise than in the usual and
regular



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course of business; or (iii) any agreement, contract or other arrangement
providing for any of the foregoing transactions.

                13.1.2. "Continuing Director" means any member of the Board of
Directors who was a member of the Board of Directors on October 1, 1997 or who
is elected to the Board of Directors after October 1, 1997 upon the
recommendation of a majority of the Continuing Directors voting separately and
as a subclass of directors on such recommendation.

                13.1.3. "Subsidiary" means a corporation, a majority of the
outstanding voting shares of which are owned, directly or indirectly, by the
corporation.

        Section 13.2. VOTE REQUIRED FOR BUSINESS COMBINATIONS.

                13.2.1. SUPERMAJORITY VOTE. Except as provided in subsections
13.2.2 and 13.2.3 hereof, the affirmative vote of the holders of not less than
two-thirds of the outstanding shares entitled to vote thereon and, to the
extent, if any, provided by resolution adopted by the Board of Directors
authorizing the issuance of a class or series of common stock or preferred
stock, the affirmative vote of the holders of not less than two-thirds of the
outstanding shares of such class or series, voting as a separate voting group,
shall be required for the adoption or authorization of a Business Combination.

                13.2.2. MAJORITY VOTE. Notwithstanding subsection 13.2.1 hereof,
if a Business Combination shall have been approved by a majority of the
Continuing Directors, voting separately and as a subclass of directors, and if
such Business Combination is otherwise required to be approved by the
corporation's shareholders pursuant to the Washington Business Corporation Act,
then the affirmative vote of the holders of not less than a majority of the
outstanding shares entitled to vote thereon and, to the extent, if any, provided
by resolution adopted by the Board of Directors authorizing the issuance of a
class or series of common stock or preferred stock, the affirmative vote of the
holders of not less than a majority of the outstanding shares of such class or
series, voting as a separate voting group, shall be required for the adoption or
authorization of such Business Combination.

                13.2.3. NO SHAREHOLDER VOTE. Notwithstanding subsection 13.2.1
or 13.2.2 hereof, if a Business Combination shall have been approved by a
majority of the Continuing Directors, voting separately and as a subclass of
directors, and if such Business Corporation is not otherwise required to be
approved by the corporation's shareholders pursuant to the Washington Business
Corporation Act, then no vote of the shareholders of the corporation shall be
required for approval of such Business Combination.







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