EXHIBIT 3.1

                          AMENDED AND RESTATED BY-LAWS

                                       OF

                               EPIX MEDICAL, INC.

                                    ARTICLE I

                                  STOCKHOLDERS

          SECTION 1. Place of Meetings. All meetings of stockholders shall be
held at such place within or without the State of Delaware as may be designated
from time to time by the Board of Directors or, if not so designated, at the
principal office of the corporation.

          SECTION 2. Annual Meeting. The annual meeting of stockholders for the
election of directors and the transaction of such other business as may properly
come before the meeting shall be held on such date and at such hour and place as
the directors or an officer designated by the directors may determine. If the
annual meeting is not held on the date designated therefor, the directors shall
cause the meeting to be held as soon thereafter as convenient.

          SECTION 3. Special Meetings. Special meetings of the stockholders may
be called at any time by the President or the Board of Directors.

          SECTION 4. Notice of Meetings. Except where some other notice is
required by law, written notice of each meeting of stockholders, stating the
place, date and hour thereof and the purposes for which the meeting is called,
shall be given by or under the direction of the Secretary, not less than ten nor
more than sixty days before the date fixed for such meeting, to each stockholder
entitled to vote at such meeting of record at the close of business on the day
fixed by the Board of Directors as a record date for the determination of the
stockholders entitled to vote at such meeting or, if no such date has been
fixed, of record at the close of business on the day before the day on which
notice is given. Notice shall be given personally to each stockholder or left at
his or her residence or usual place of business or mailed postage prepaid and
addressed to the stockholder at his or her address as it appears upon the
records of the corporation. In case of the death, absence, incapacity or refusal
of the Secretary, such notice may be given by a person designated either by the
Secretary or by the person or persons calling the meeting or by the Board of
Directors. A waiver of such notice in writing, signed by the person or persons
entitled to said notice, whether before or after the time stated therein, shall
be deemed equivalent to such notice. Attendance of a person at a meeting of
stockholders shall constitute a waiver of notice of such meeting, except when
the stockholder attends a meeting for the express purpose of objecting, at the
beginning of the meeting, to the transaction of any business because the meeting
is not lawfully called or convened. Neither the business to be transacted at,
nor the purpose of, any regular or special meeting of the stockholders need be
specified in any written waiver of notice. Notice of any meeting of the
stockholders shall be deemed to have been given to any person who may become a
stockholder of record after the mailing


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of such notice and prior to such meeting. Except as required by statute, notice
of any adjourned meeting of the stockholders shall not be required.

          SECTION 5. Stockholder Nominations of Directors. Only persons who are
nominated in accordance with the following procedures shall be eligible for
election as directors at any annual or special meeting. Nominations of persons
for election as directors may be made by or at the direction of the Board of
Directors, or by any stockholder entitled to vote for the election of directors
at the meeting who complies with the notice procedures set forth in this Section
5. Such nominations, other than those made by or at the direction of the Board,
shall be made pursuant to timely notice in writing to the Chairman, if any, the
President, the Secretary or the Treasurer. To be timely, a stockholder's notice
shall be delivered to or mailed and received at the principal executive offices
of the corporation not less than 50 days nor more than 75 days prior to the
meeting; provided, however, that if less than 65 days' notice or prior public
disclosure of the date of the meeting is given or made to stockholders, notice
by the stockholder to be timely must be so received not later than the close of
business on the 15th day following the day on which such notice of the date of
the meeting was mailed or such public disclosure was made. Such stockholder's
notice shall set forth: (a) as to each person whom the stockholder proposes to
nominate for election or re-election as a director, (i) the name, age, business
address and residence address of the person, (ii) the principal occupation or
employment of the person, (iii) the class and number of shares of capital stock
of the corporation which are beneficially owned by the person and (iv) any other
information relating to the person that is required to be disclosed in
solicitations for proxies for election of directors pursuant to Regulation 14A
under the Securities Exchange Act of 1934, as amended; and (b) as to the
stockholder giving the notice (i) the name and record address of such
stockholder and (ii) the class and number of shares of capital stock of the
corporation which are beneficially owned by such stockholder. No person shall be
eligible for election as a director at any annual or special meeting of
stockholders unless nominated in accordance with the procedures set forth
herein. Nothing in this Section 5 shall be deemed to grant stockholders the
right have such nominations included on the agenda or in the notice or proxy
materials for such meeting except as otherwise required by law.

     The chairman of the meeting shall, if the facts warrant, determine and
declare to the meeting that a nomination was not made in accordance with the
foregoing procedure, and if he should so determine, he shall so declare to the
meeting and the defective nomination shall be disregarded.

          SECTION 6. Record Date. The Board of Directors may fix in advance a
record date for the determination of the stockholders entitled to notice of or
to vote at any meeting of stockholders, or entitled to receive payment of any
dividend or other distribution or allotment of any rights, or entitled to
exercise any rights in respect of any change, conversion or exchange of stock,
or for the purpose of any other lawful action. Such record date shall not be
more than 60 nor less than 10 days before the date of such meeting, nor more
than 60 days prior to any other action to which such record date relates.

     If no record date is fixed, the record date for determining stockholders
entitled to notice of or to vote at a meeting of stockholders shall be at the
close of business on the day before the day on which notice is given, or, if
notice is waived, at the close of business on the day before the day on which
the meeting is held. The record date for determining stockholders for any other
purpose shall be at the close of business on the day on which the Board of
Directors adopts the resolution relating to such purpose. A determination of
stockholders of record entitled to notice of or to vote at a meeting of
stockholders shall apply to any adjournment of the meeting; provided, however,
that the Board of Directors may fix a new record date for the adjourned meeting.


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          SECTION 7. Advance Notice of Stockholder-Proposed Business at Annual
Meetings. At an annual meeting of the stockholders, only such business shall be
conducted as shall have been properly brought before the meeting. To be brought
properly before an annual meeting, business must be either (a) specified in the
notice of meeting (or any supplement thereto) given by or at the direction of
the President or the Board of Directors, (b) otherwise properly brought before
the meeting by or at the direction of the Board or (c) otherwise properly
brought before the meeting by a stockholder. In addition to any other applicable
requirements, for business to be brought properly before an annual meeting by a
stockholder, the stockholder must have given timely notice thereof in writing to
the Chairman, if any, the President, the Secretary or the Treasurer. To be
timely, a stockholder's notice must be delivered to or mailed and received at
the principal executive offices of the corporation not less than 50 days nor
more than 75 days prior to the meeting; provided, however, that if less than 65
days' notice or prior public disclosure of the date of the meeting is given or
made to stockholders, notice by the stockholder to be timely must be so received
not later than the close of business on the 15th day following the day on which
such notice of the date of the annual meeting was mailed or such public
disclosure was made. A stockholder's notice shall set forth as to each matter
the stockholder proposes to bring before the annual meeting (i) a brief
description of the business desired to be brought before the annual meeting and
the reasons for conducting such business at the annual meeting, (ii) the name
and record address of the stockholder proposing such business, (iii) the class
and number of shares of the corporation which are beneficially owned by the
stockholder and (iv) any material interest of the stockholder in such business.

     Notwithstanding anything in these by-laws to the contrary, no business
shall be conducted at the annual meeting except in accordance with the
procedures set forth in this Section 6, provided, however, that nothing in this
Section 6 shall be deemed to preclude discussion by any stockholder of any
business properly brought before the annual meeting in accordance with said
procedure; provided, further, that nothing in this Section 6 shall be deemed to
grant stockholders the right have such business included on the agenda or in the
notice or proxy materials for such meeting except as otherwise required by law.

     The chairman of an annual meeting shall, if the facts warrant, determine
and declare to the meeting that business was not properly brought before the
meeting in accordance with the provisions of this Section 6, and if he should so
determine, he shall so declare to the meeting and any such business not properly
brought before the meeting shall not be transacted.

          SECTION 8. Voting List. The officer who has charge of the stock ledger
of the corporation shall make or have made, at least ten days before every
meeting of stockholders, a complete list of the stockholders, arranged in
alphabetical order, and showing the address of each stockholder and the number
of shares registered in the name of each stockholder. Such list shall be open to
the examination of any stockholder, for any purpose germane to the meeting,
during ordinary business hours, for a period of at least ten days prior to the
meeting, either at a place within the city or other municipality or community
where the meeting is to be held, which place shall be specified in the notice of
the meeting, or if not so specified, at the place where the meeting is to be
held. The list shall also be produced and kept at the time and place of the
meeting during the whole time thereof, and may be inspected by any stockholder
who is present. The stock ledger shall be the only evidence as to who are the
stockholders entitled to examine the stock ledger, the list required by this
section or the books of the corporation, or to vote at any meeting of
stockholders.

          SECTION 9. Quorum of Stockholders. At any meeting of the stockholders,
the holders of a majority in interest of all stock issued and outstanding and
entitled to vote upon a question to be considered at the meeting, present in
person or represented by proxy, shall constitute a


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quorum for the consideration of such question, but a smaller group may adjourn
any meeting from time to time. When a quorum is present at any meeting, a
majority of the stock represented thereat and entitled to vote shall, except
where a larger vote is required by law, by the Certificate of Incorporation, or
by these by-laws, decide any question brought before such meeting. Any election
by stockholders shall be determined by a plurality of the vote cast by the
stockholders entitled to vote at the election.

          SECTION 10. Proxies and Voting. Unless otherwise provided in the
Certificate of Incorporation, each stockholder shall at every meeting of the
stockholders be entitled to one vote in person or by proxy for each share of the
capital stock held of record by such stockholder, but no proxy shall be voted or
acted upon after three years from its date, unless said proxy provides for a
longer period. Persons holding stock in a fiduciary capacity shall be entitled
to vote the shares so held, and persons whose stock is pledged shall be entitled
to vote, unless in the transfer by the pledger on the books of the corporation
the pledgee shall have been expressly empowered to vote thereon, in which case
only the pledgee or the pledgee's proxy may represent said stock and vote
thereon. Shares of the capital stock of the corporation belonging to the
corporation or to another corporation, a majority of whose shares entitled to
vote in the election of directors is owned by the corporation, shall neither be
entitled to vote nor be counted for quorum purposes.

          SECTION 11. Conduct of Meeting. Meetings of the stockholders shall be
presided over by one of the following officers in the order of seniority and if
present and acting: the President, a Vice President, the Chairman of the Board,
if any, the Vice Chairman of the Board, if any, or, if none of the foregoing is
in office and present and acting, a chairman to be chosen by the stockholders.
The Secretary of the corporation, if present, or an Assistant Secretary, shall
act as secretary of every meeting, but if neither the Secretary nor an Assistant
Secretary is present the chairman of the meeting shall appoint a secretary of
the meeting.

                                   ARTICLE II

                                    DIRECTORS

          SECTION 1. General Powers. The business and affairs of the corporation
shall be managed by or under the direction of a Board of Directors, who may
exercise all of the powers of the corporation which are not by law or the
Certificate of Incorporation required to be exercised by the stockholders. In
the event of a vacancy in the Board of Directors, the remaining directors,
except as otherwise provided by law, may exercise the powers of the full Board
until the vacancy is filled.

          SECTION 2. Number, Election, Tenure and Qualification. Subject to any
restrictions contained in the Certificate of Incorporation, the number of
directors that shall constitute the Board of Directors shall be fixed by
resolution of the Board of Directors but in no event shall be less than three.
Directors shall be elected in the manner provided in the Certificate of
Incorporation by such stockholders as have the right to vote thereon. The number
of directors may be increased or decreased by action of the Board of Directors.
Directors need not be stockholders of the corporation.

          SECTION 3. Enlargement of the Board. Subject to the restrictions
contained in the Certificate of Incorporation, the number of the Board of
Directors may be increased at any time, such increase to be effective
immediately, by vote of a majority of the directors then in office.


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          SECTION 4. Vacancies. Unless and until filled by the stockholders, any
vacancy in the Board of Directors, however occurring, including a vacancy
resulting from an enlargement of the Board and an unfilled vacancy resulting
from the removal of any director for cause, may be filled in the manner provided
in the Certificate of Incorporation. When one or more directors shall resign
from the Board, effective at a future date, a majority of the directors then in
office, including those who have so resigned, shall have the power to fill such
vacancy or vacancies, the vote thereon to take effect when such resignation or
resignations shall become effective. If at any time there are no directors in
office, then an election of directors may be held in accordance with the General
Corporation Law of the State of Delaware.

          SECTION 5. Resignation. Any director may resign at any time upon
written notice to the corporation. Such resignation shall take effect at the
time specified therein, or if no time is specified, at the time of its receipt
by the President or Secretary.

          SECTION 6. Removal. Directors may be removed from office only as
provided in the Certificate of Incorporation. The vacancy or vacancies thus
created may be filled by the stockholders at the meeting held for the purpose of
removal or, if not so filled, by the directors in the manner provided in Section
4 of this Article II.

          SECTION 7. Committees. The Board of Directors may, by resolution or
resolutions passed by a majority of the whole Board of Directors, designate one
or more committees, each committee to consist of one or more directors of the
corporation. The Board of Directors may designate one or more directors as
alternate members of any committee, who may replace any absent or disqualified
member at any meeting of the committee. In the absence or disqualification of
any member of such committee or committees, 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 member of
the Board of Directors to act at the meeting in the place of such absent or
disqualified member.

     A majority of all the members of any such committee may fix its rules of
procedure, determine its action and fix the time and place, whether within or
without the State of Delaware, of its meetings and specify what notice thereof,
if any, shall be given, unless the Board of Directors shall otherwise by
resolution provide. The Board of Directors shall have the power to change the
members of any such committee at any time, to fill vacancies therein and to
discharge any such committee, either with or without cause, at any time.

     Any such committee, unless otherwise provided in the resolution of the
Board of Directors, or in these by-laws, shall have and may exercise all the
powers and authority of the Board of Directors in the management of the business
and affairs of the corporation, and may authorize the seal of the corporation to
be affixed to all papers which may require it; but no such committee shall have
such power or authority in reference to amending the Certificate of
Incorporation, adopting an agreement of merger or consolidation, recommending to
the stockholders the sale, lease or exchange of all or substantially all of the
corporation's property and assets, recommending a dissolution of the corporation
or a revocation of a dissolution, or amending the By-laws of the corporation,
and, unless the resolution or these By-laws expressly so provide, no such
committee shall have the power or the authority to declare a dividend or to
authorize the issuance of stock.

     Each committee shall keep regular minutes of its meetings and make such
reports as the Board of Directors may from time to time request.


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          SECTION 8. Meetings of the Board of Directors. Regular meetings of the
Board of Directors may be held without call or formal notice at such places
either within or without the State of Delaware and at such times as the Board
may by vote from time to time determine. A regular meeting of the Board of
Directors may be held without call or formal notice immediately after and at the
same place as the annual meeting of the stockholders, or any special meeting of
the stockholders at which a Board of Directors is elected.

     Special meetings of the Board of Directors may be held at any place either
within or without the State of Delaware at any time when called by the Chairman
of the Board of Directors, the President, Treasurer, Secretary, or two or more
directors. Reasonable notice of the time and place of a special meeting shall be
given to each director unless such notice is waived by attendance or by written
waiver in the manner provided in these by-laws for waiver of notice by
stockholders. Notice may be given by, or by a person designated by, the
Secretary, the person or persons calling the meeting, or the Board of Directors.
No notice of any adjourned meeting of the Board of Directors shall be required.
In any case it shall be deemed sufficient notice to a director to send notice by
mail at least seventy-two hours, or by telegram at least forty-eight hours,
before the meeting, addressed to such director at his or her usual or last known
business or home address.

     Directors or members of any committee designated by the directors may
participate in a meeting of the Board of Directors or such committee by means of
conference telephone or similar communications equipment by means of which all
persons participating in the meeting can hear each other, and participation by
such means shall constitute presence in person at such meeting.

          SECTION 9. Quorum and Voting. A majority of the total number of
directors shall constitute a quorum, except that when a vacancy or vacancies
exist in the Board, a majority of the directors then in office (but not less
than one-third of the total number of the directors) shall constitute a quorum.
A majority of the directors present, whether or not a quorum is present, may
adjourn any meeting from time to time. The vote of a majority of the directors
present at any meeting at which a quorum is present shall be the act of the
Board of Directors, except where a different vote is required or permitted by
law, by the Certificate of Incorporation, or by these by-laws.

          SECTION 10. Compensation. The Board of Directors may fix fees for
their services and for their membership on committees, and expenses of
attendance may be allowed for attendance at each meeting. Nothing herein
contained shall be construed to preclude any director from serving the
corporation in any other capacity as an officer, agent or otherwise, and
receiving compensation therefor.

          SECTION 11. Action Without Meeting. Any action required or permitted
to be taken at any meeting of the Board of Directors, or of any committee
thereof, may be taken without a meeting, and without notice, if a written
consent thereto is signed by all members of the Board of Directors, or of such
committee, as the case may be, and such written consent is filed with the
minutes of proceedings of the Board of Directors or such committee.

                                   ARTICLE III

                                    OFFICERS


                                      -6-



          SECTION 1. Titles. The officers of the corporation shall consist of a
President, a Secretary, a Treasurer, and such other officers with such other
titles as the Board of Directors shall determine, including without limitation a
Chairman of the Board, a Vice Chairman of the Board, and one or more Vice
Presidents, Assistant Treasurers, or Assistant Secretaries.

          SECTION 2. Election and Term of Office. The officers of the
corporation shall be elected annually by the Board of Directors at its first
meeting following the annual meeting of the stockholders. Each officer shall
hold office until his or her successor is elected and qualified, unless a
different term is specified in the vote electing such officer, or until his or
her earlier death, resignation or removal.

          SECTION 3. Qualification. Unless otherwise provided by resolution of
the Board of Directors, no officer, other than the Chairman or Vice Chairman of
the Board, need be a director. No officer need be a stockholder. Any number of
offices may be held by the same person, as the directors shall determine.

          SECTION 4. Removal. Any officer may be removed, with or without cause,
at any time, by resolution adopted by the Board of Directors.

          SECTION 5. Resignation. Any officer may resign by delivering a written
resignation to the corporation at its principal office or to the President or
Secretary. Such resignation shall be effective upon receipt or at such later
time as may be specified therein.

          SECTION 6. Vacancies. The Board of Directors may at any time fill any
vacancy occurring in any office for the unexpired portion of the term and may
leave unfilled for such period as it may determine any office other than those
of President, Treasurer and Secretary.

          SECTION 7. Powers and Duties. The officers of the corporation shall
have such powers and perform such duties as are specified herein and as may be
conferred upon or assigned to them by the Board of Directors, and shall have
such additional powers and duties as are incident to their office except to the
extent that resolutions of the Board of Directors are inconsistent therewith.

          SECTION 8. President and Vice Presidents. The President shall be the
chief executive officer of the corporation, shall preside at all meetings of the
stockholders and the Board of Directors unless a Chairman or Vice Chairman of
the Board is elected by the Board, empowered to preside, and present at such
meeting, shall have general and active management of the business of the
corporation and general supervision of its officers, agents and employees, and
shall see that all orders and resolutions of the Board of Directors are carried
into effect.

     In the absence of the President or in the event of his or her inability or
refusal to act, the Vice President if any (or in the event there be more than
one Vice President, the Vice Presidents in the order designated by the
directors, or in the absence of any designation, then in the order of their
election) shall perform the duties of the President, and when so acting, shall
have all the powers of and be subject to all the restrictions upon the
President. The Board of Directors may assign to any Vice President the title of
Executive Vice President, Senior Vice President or any other title selected by
the Board of Directors.

          SECTION 9. Secretary and Assistant Secretaries. The Secretary shall
attend all meetings of the Board of Directors and of the stockholders and record
all the proceedings of such meetings in a book to be kept for that purpose,
shall give, or cause to be given, notice of all meetings


                                      -7-



of the stockholders and special meetings of the Board of Directors, shall
maintain a stock ledger and prepare lists of stockholders and their addresses as
required and shall have custody of the corporate seal which the Secretary or any
Assistant Secretary shall have authority to affix to any instrument requiring it
and attest by any of their signatures. The Board of Directors may give general
authority to any other officer to affix and attest the seal of the corporation.

     The Assistant Secretary if any (or if there be more than one, the Assistant
Secretaries in the order determined by the Board of Directors of if there be no
such determination, then in the order of their election) shall, in the absence
of the Secretary or in the event of the Secretary's inability or refusal to act,
perform the duties and exercise the powers of the Secretary.

          SECTION 10. Treasurer and Assistant Treasurers. The Treasurer shall
have the custody of the corporate funds and securities, shall keep full and
accurate accounts of receipts and disbursements in books belonging to the
corporation and shall deposit all moneys and other valuable effects in the name
and to the credit of the corporation in such depositories as may be designated
by the Board of Directors. The Treasurer shall disburse the funds of the
corporation as may be ordered by the Board of Directors or the President, taking
proper vouchers for such disbursements, and shall render to the President and
the Board of Directors, at its regular meetings, or whenever they may require
it, an account of all transactions and of the financial condition of the
corporation.

     The Assistant Treasurer if any (or if there be more than one, the Assistant
Treasurers in the order determined by the Board of Directors or if there be no
such determination, then in the order of their election) shall, in the absence
of the Treasurer or in the event of his or her inability or refusal to act,
perform the duties and exercise the powers of the Treasurer.

          SECTION 11. Bonded Officers. The Board of Directors may require any
officer to give the corporation a bond in such sum and with such surety or
sureties as shall be satisfactory to the Board of Directors upon such terms and
conditions as the Board of Directors may specify, including without limitation a
bond for the faithful performance of the duties of such officer and for the
restoration to the corporation of all property in his or her possession or
control belonging to the corporation.

          SECTION 12. Salaries. Officers of the corporation shall be entitled to
such salaries, compensation or reimbursement as shall be fixed or allowed from
time to time by the Board of Directors.

                                   ARTICLE IV

                                      STOCK

          SECTION 1. Certificates of Stock. One or more certificates of stock,
signed by the Chairman or Vice Chairman of the Board of Directors or by the
President or Vice President and by the Treasurer or an Assistant Treasurer or
the Secretary or an Assistant Secretary, shall be issued to each stockholder
certifying, in the aggregate, the number of shares owned by the stockholder in
the corporation. Any or all signatures on any such certificate may be
facsimiles. In case any officer, transfer agent or registrar who shall have
signed or whose facsimile signature shall have been placed upon a certificate
shall have ceased to be such officer, transfer agent or registrar before such
certificate is issued, it may be issued by the corporation with the same effect
as if he or she were such officer, transfer agent or registrar at the date of
issue.


                                      -8-



     Each certificate for shares of stock which are subject to any restriction
on transfer pursuant to the Certificate of Incorporation, the by-laws,
applicable securities laws, or any agreement among any number of stockholders or
among such holders and the corporation shall have conspicuously noted on the
face or back of the certificate either the full text of the restriction or a
statement of the existence of such restriction.

          SECTION 2. Transfers of Shares of Stock. Subject to the restrictions,
if any, stated or noted on the stock certificates, shares of stock may be
transferred on the books of the corporation by the surrender to the corporation
or its transfer agent of the certificate representing such shares properly
endorsed or accompanied by a written assignment or power of attorney properly
executed, and with such proof of authority or the authenticity of signature as
the corporation or its transfer agent may reasonably require. The corporation
shall be entitled to treat the record holder of stock as shown on its books as
the owner of such stock for all purposes, including the payment of dividends and
the right to vote with respect to that stock, regardless of any transfer, pledge
or other disposition of that stock, until the shares have been transferred on
the books of the corporation in accordance with the requirements of these
by-laws.

          SECTION 3. Lost Certificates. A new certificate of stock may be issued
in the place of any certificate theretofore issued by the corporation and
alleged to have been lost, stolen, destroyed, or mutilated, upon such terms in
conformity with law as the Board of Directors shall prescribe. The directors
may, in their discretion, require the owner of the lost, stolen, destroyed or
mutilated certificate, or the owner's legal representatives, to give the
corporation a bond, in such sum as they may direct, to indemnify the corporation
against any claim that may be made against it on account of the alleged loss,
theft, destruction or mutilation of any such certificate, or the issuance of any
such new certificate.

          SECTION 4. Fractional Share Interests. The corporation may, but shall
not be required to, issue fractions of a share. If the corporation does not
issue fractions of a share, it shall (1) arrange for the disposition of
fractional interests by those entitled thereto, (2) pay in cash the fair value
of fractions of a share as of the time when those entitled to receive such
fractions are determined or (3) issue scrip or warrants in registered or bearer
form which shall entitle the holder to receive a certificate for a full share
upon the surrender of such scrip or warrants aggregating a full share. A
certificate for a fractional share shall, but scrip or warrants shall not unless
otherwise provided therein, entitle the holder to exercise voting rights, to
receive dividends thereon, and to participate in any of the assets of the
corporation in the event of liquidation. The Board of Directors may cause scrip
or warrants to be issued subject to the conditions that they shall become void
if not exchanged for certificates representing full shares before a specified
date, or subject to the conditions that the shares for which scrip or warrants
are exchangeable may be sold by the corporation and the proceeds thereof
distributed to the holders of scrip or warrants, or subject to any other
conditions which the Board of Directors may impose.

          SECTION 5. Dividends. Subject to the provisions of the Certificate of
Incorporation, the Board of Directors may, out of funds legally available
therefor, at any regular or special meeting, declare dividends upon the common
stock of the corporation as and when they deem expedient.


                                      -9-



                                    ARTICLE V

                                    INSURANCE

          SECTION 1. Indemnification. The corporation shall, to the full extent
permitted by the General Corporation Law of the State of Delaware, as amended
from time to time, the Certificate of Incorporation, and any agreement of the
Corporation, indemnify each person whom it may indemnify pursuant thereto.

          SECTION 2. Insurance. The corporation shall have power to purchase and
maintain insurance on behalf of any person who is or was a director, officer,
employee or agent of the corporation, or is or was serving at the request of the
corporation as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise against any liability
asserted against such person and incurred by such person in any such capacity or
arising out of such person's status as such, whether or not the corporation
would have the power to indemnify such person against such liability under the
provisions of the General Corporation Law of the State of Delaware.

                                   ARTICLE VI

                               GENERAL PROVISIONS

          SECTION 1. Fiscal Year. Except as otherwise designated from time to
time by the Board of Directors, the fiscal year of the corporation shall begin
on the first day of January and end on the last day of December.

          SECTION 2. Corporate Seal. The corporate seal shall be in such form as
shall be approved by the Board of Directors. The Secretary shall be the
custodian of the seal. The Board of Directors may authorize a duplicate seal to
be kept and used by any other officer.

          SECTION 3. Certificate of Incorporation. All references in these
by-laws to the Certificate of Incorporation shall be deemed to refer to the
Certificate of Incorporation of the corporation, as in effect from time to time.

          SECTION 4. Execution of Instruments. The Chairman and Vice Chairman of
the Board of Directors, if any, the President, any Vice President, and the
Treasurer shall have power to execute and deliver on behalf and in the name of
the corporation any instrument requiring the signature of an officer of the
corporation, including deeds, contracts, mortgages, bonds, notes, debentures,
checks, drafts, and other orders for the payment of money. In addition, the
Board of Directors may expressly delegate such powers to any other officer or
agent of the corporation.

          SECTION 5. Voting of Securities. Except as the directors may otherwise
designate, the President or Treasurer may waive notice of, and act as, or
appoint any person or persons to act as, proxy or attorney-in-fact for this
corporation (with or without power of substitution) at any meeting of
stockholders or shareholders of any other corporation or organization the
securities of which may be held by this corporation.

          SECTION 6. Evidence of Authority. A certificate by the Secretary, or
an Assistant Secretary, or a temporary secretary, as to any action taken by the
stockholders, directors, a committee


                                      -10-



or any officer or representative of the corporation shall, as to all persons who
rely on the certificate in good faith, be conclusive evidence of that action.

          SECTION 7. Transactions with Interested Parties. No contract or
transaction between the corporation and one or more of the directors or
officers, or between the corporation and any other corporation, partnership,
association, or other organization in which one or more of the directors or
officers are directors or officers, or have a financial interest, shall be void
or voidable solely for that reason, or solely because the director or officer is
present at or participates in the meeting of the Board of Directors or a
committee of the Board of Directors which authorizes the contract or transaction
or solely because the vote of any such director is counted for such purpose, if:

     (1) The material facts as to the relationship or interest and as to the
contract or transaction are disclosed or are known to the Board of Directors or
the committee, and the Board or committee in good faith authorizes the contract
or transaction by the affirmative votes of a majority of the disinterested
directors, even though the disinterested directors be less than a quorum; or

     (2) The material facts as to the relationship or interest and as to the
contract or transaction are disclosed or are known to the stockholders entitled
to vote thereon, and the contract or transaction is specifically approved in
good faith by vote of the stockholders; or

     (3) The contract or transaction is fair as to the corporation as of the
time it is authorized, approved or ratified by the Board of Directors, a
committee of the Board of Directors, or the stockholders.

     Common or interested directors may be counted in determining the presence
of a quorum at a meeting of the Board of Directors or of a committee which
authorizes the contract or transaction.

          SECTION 8. Books and Records. The books and records of the corporation
shall be kept at such places within or without the State of Delaware as the
Board of Directors may from time to time determine.

                                   ARTICLE VII

                                   AMENDMENTS

          SECTION 1. By the Board of Directors. These by-laws may be altered,
amended or repealed or new by-laws may be adopted by the affirmative vote of a
majority of the directors present at any regular or special meeting of the Board
of Directors at which a quorum is present.

          SECTION 2. By the Stockholders. These by-laws may be altered, amended
or repealed or new by-laws may be adopted by the affirmative vote of the holders
of a majority of the shares of the capital stock of the corporation issued and
outstanding and entitled to vote at any regular meeting of stockholders, or at
any special meeting of stockholders provided notice of such alteration,
amendment, repeal or adoption of new by-laws shall have been stated in the
notice of such special meeting.


                                      -11-



                            CERTIFICATE OF AMENDMENT

                     TO THE AMENDED AND RESTATED BY-LAWS OF

                           EPIX PHARMACEUTICALS, INC.

     The undersigned, being the Chief Financial Officer of EPIX Pharmaceuticals,
Inc., a Delaware corporation (the "Corporation"), hereby certifies that the
Board of Directors of the Corporation approved an amendment to the By-Laws of
the Corporation, effective as of the date indicated below.

1.   That the By-Laws be amended by deleting in its entirety Article IV, Section
     1 and substituting therefore the following:

     "SECTION 1. Certificates of Stock. Each stockholder shall be entitled to a
     certificate of the capital stock of the Corporation in such form as may
     from time to time be prescribed by the Board of Directors. Such certificate
     shall be signed by the Chairman or Vice-Chairman of the Board of Directors,
     the President or a Vice President and by the Treasurer or an Assistant
     Treasurer, or the Secretary or an Assistant Secretary. The Corporation seal
     and the signatures by the Corporation's officers, the transfer agent or the
     registrar may be facsimiles. In case any officer, transfer agent or
     registrar who has signed or whose facsimile signature has been placed on
     such certificate shall have ceased to be such officer, transfer agent or
     registrar before such certificate is issued, it may be issued by the
     Corporation with the same effect as if he or she were such officer,
     transfer agent or registrar at the time of its issue. Every certificate for
     shares of stock which are subject to any restriction on transfer and every
     certificate issued when the Corporation is authorized to issue more than
     one class or series of stock shall contain such legend with respect thereto
     as is required by law."

Date: March 28, 2007


                                        /s/ KIM C. DRAPKIN
                                        ----------------------------------------
                                        Kim C. Drapkin, Chief Financial Officer