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                                RESTATED BYLAWS

                                      OF

                              ADOLOR CORPORATION
                       (fka Opian Pharmaceutical, Inc.)

                                   ARTICLE I

                                 STOCKHOLDERS
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1.1  Meetings.
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     1.1.1   Place. Meetings of the stockholders shall be held at such place as
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may be designated by the board of directors.

     1.1.2   Annual Meeting. An annual meeting of the stockholders for the
election of directors and for other business shall be held on such date and at
such time as may be fixed by the board of directors.

     1.1.3   Special Meetings. Special meetings of the stockholders may be
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called at any time by the president, or by any two members of the board of
directors, or by the holders of a majority of the outstanding shares of Common
Stock of the Company entitled to vote at the meeting.

     1.1.4   Quorum. The presence, in person or by proxy, of the holders of a
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majority of the outstanding shares of stock of the Company entitled to vote on a
particular matter shall constitute a quorum for the purpose of considering such
matter.

     1.1.5   Voting Rights. Except as otherwise provided herein, in the
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certificate of incorporation or by law, every stockholder shall have the right
at every meeting of stockholders to one vote for every share standing in the
name of such stockholder on the books of the Company which is entitled to vote
at such meeting. Every stockholder may vote either in person or by proxy.

                                  ARTICLE II

                                   DIRECTORS
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2.1  Number and Term. The number of Directors shall be fixed from time to time
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exclusively pursuant to a resolution adopted by a majority of the entire Board
of Directors, but shall consist of not less than five (5) Directors nor more
than nine (9) Directors. The Directors, other than those who may be elected by
the holders of any series of Preferred Stock, if any, shall be divided into
three classes, designated Classes I, II and III, which shall be as nearly equal
in number as possible. Directors of Class I shall be elected to hold office for
a term expiring at the annual meeting of stockholders to be held in 2002,
Directors of Class II shall be elected to hold office for a term expiring at the
annual meeting of stockholders to be held in 2003, and Directors of Class III
shall be elected to hold office for a term expiring at the
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annual meeting of stockholders to be held in 2004. At each succeeding annual
meeting of stockholders following such initial classification and election, the
respective successors of each class shall be elected for three year terms. Each
Director (whenever elected) shall hold office until his or her successor has
been duly elected and qualified, or until his or her earlier death, insanity,
retirement, resignation or removal. Directors need not be residents of the State
of Delaware.

2.2  Meetings.
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     2.2.1   Place. Meetings of the board of directors shall be held at such
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place as may be designated by the board or in the notice of the meeting.

     2.2.2   Regular Meetings. Regular meetings of the board of directors shall
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be held at such times as the board may designate. Notice of regular meetings
need not be given.

     2.2.3   Special Meetings. Special meetings of the board may be called by
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direction of the president or by any two members of the board, in either case on
three days' notice to each director, either personally or by mail, telegram or
facsimile transmission.

     2.2.4   Quorum. A majority of all the directors in office shall constitute
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a quorum for the transaction of business at any meeting.

     2.2.5   Voting. Except as otherwise provided herein, in the certificate of
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incorporation or by law, the vote of a majority of the directors present at any
meeting at which a quorum is present shall constitute the act of the board of
directors.

     2.2.6   Committees. The board of directors may, by resolution adopted by a
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majority of the whole board, designate one or more committees, each committee to
consist of one or more directors and such alternate members (also directors) as
may be designated by the board. Unless otherwise provided herein, in the absence
or disqualification of any member of a committee, the member or members thereof
present at any meeting and not disqualified from voting, whether or not such
member or members constitute a quorum, may unanimously appoint another director
to act at the meeting in the place of any such absent or disqualified member.
Except as otherwise provided herein, in the certificate of incorporation or by
law, any such committee shall have and may exercise the powers of the full board
of directors to the extent provided in the resolution of the board directing the
committee.

                                  ARTICLE III

                                   OFFICERS
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3.1  Election. At its first meeting after each annual meeting of the
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stockholders, the board of directors shall elect a president, treasurer,
secretary and such other officers as it deems advisable.

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3.2  Authority, Duties and Compensation. The officers shall have such authority,
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perform such duties and serve for such compensation as may be determined by
resolution of the board of directors. Except as otherwise provided by board
resolution, (i) the president shall be the chief executive officer of the
Company, shall have general supervision over the business and operations of the
Company, may perform any act and execute any instrument for the conduct of such
business and operations and shall preside at all meetings of the board and
stockholders, (ii) the other officers shall have the duties customarily related
to their respective offices, and (iii) any vice president, or vice presidents in
the order determined by the board, shall in the absence of the president have
the authority and perform the duties of the president.

                                  ARTICLE IV

                                INDEMNIFICATION
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4.1  Right to Indemnification. The Company shall indemnify any person who was or
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is 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 (a "proceeding"), by reason of the fact that such person is or was
a director or officer of the Company or a constituent corporation absorbed in a
consolidation or merger, or is or was serving at the request of the Company or a
constituent corporation absorbed in a consolidation or merger, as a director or
officer of another corporation, partnership, joint venture, trust or other
enterprise, or is or was a director or officer of the Company serving at its
request as an administrator, trustee or other fiduciary of one or more of the
employee benefit plans of the Company or other enterprise, against expenses
(including attorneys' fees), liability and loss actually and reasonably incurred
or suffered by such person in connection with such proceeding, whether or not
the indemnified liability arises or arose from any threatened, pending or
completed proceeding by or in the right of the Company, except to the extent
that such indemnification is prohibited by applicable law.

4.2  Advance of Expenses. Expenses incurred by a director or officer of the
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Company in defending a proceeding shall be paid by the Company in advance of the
final disposition of such proceeding subject to the provisions of any applicable
statute.

4.3  Procedure for Determining Permissibility. To determine whether any
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indemnification or advance of expenses under this Article IV is permissible, the
board of directors by a majority vote of a quorum consisting of directors not
parties to such proceeding may, and on request of any person seeking
indemnification or advance of expenses shall be required to, determine in each
case whether the applicable standards in any applicable statute have been met,
or such determination shall be made by independent legal counsel if such quorum
is not obtainable, or, even if obtainable, a majority vote of a quorum of
disinterested directors so directs, provided that, if there has been a change in
control of the Company between the time of the action or failure to act giving
rise to the claim for indemnification or advance of expenses and the time such
claim is made, at the option of the person seeking indemnification or advance of
expenses, the permissibility of indemnification or advance of expenses shall be
determined by independent legal counsel. The reasonable expenses of any director
or officer in prosecuting a successful

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claim for indemnification, and the fees and expenses of any special legal
counsel engaged to determine permissibility of indemnification or advance of
expenses, shall be borne by the Company.

4.4   Contractual Obligation. The obligations of the Company to indemnify a
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director or officer under this Article IV, including the duty to advance
expenses, shall be considered a contract between the Company and such director
or officer, and no modification or repeal of any provision of this Article IV
shall affect, to the detriment of the director or officer, such obligations of
the Company in connection with a claim based on any act or failure to act
occurring before such modification or repeal.

4.5   Indemnification Not Exclusive; Inuring of Benefit. The indemnification and
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advance of expenses provided by this Article IV shall not be deemed exclusive of
any other right to which one indemnified may be entitled under any statute,
provision of the Certificate of Incorporation, these bylaws, agreement, vote of
stockholders or disinterested directors or otherwise, both as to action in such
person's official capacity and as to action in another capacity while holding
such office, and shall inure to the benefit of the heirs, executors and
administrators of any such person.

4.6   Insurance and Other Indemnification. The board of directors shall have the
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power to (i) authorize the Company to purchase and maintain, at the Company's
expense, insurance on behalf of the Company and on behalf of others to the
extent that power to do so has not been prohibited by statute, (ii) create any
fund of any nature, whether or not under the control of a trustee, or otherwise
secure any of its indemnification obligations, and (iii) give other
indemnification to the extent permitted by statute.

                                   ARTICLE V

                        TRANSFER OF SHARE CERTIFICATES
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          Transfers of share certificates and the shares represented thereby
shall be made on the books of the Company only by the registered holder or by
duly authorized attorney.  Transfers shall be made only on surrender of the
share certificate or certificates.

                                  ARTICLE VI

                                  AMENDMENTS
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          These bylaws may be amended or repealed at any regular or special
meeting of the board of directors by vote of a majority of all directors in
office or at any annual or special meeting of stockholders by vote of holders of
a majority of the outstanding stock entitled to vote.  Notice of any such annual
or special meeting of stockholders shall set forth the proposed change or a
summary thereof.

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