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                                                                     Exhibit 4.2

                                 MEDAREX, INC.

                          AMENDED AND RESTATED BY-LAWS

                                    ARTICLE I

                                     OFFICES

     Section 1. The registered office of the Corporation shall be located in
Trenton, New Jersey. The principal office shall be located at 707 State Road,
Suite #206, Princeton, NJ 08540.

     Section 2. The Corporation may also have offices at such other places both
within and without the State of New Jersey as the Board of Directors may from
time to time determine or the business of the Corporation may require.


                                   ARTICLE II

                         ANNUAL MEETING OF SHAREHOLDERS

     Section 1. All meetings of shareholders for the election of Directors shall
be held in the Township of Princeton, State of New Jersey, or at such other
place as may be fixed from time to time by the Board of Directors.

     Section 2. Annual meetings of shareholders shall be held on the third
Thursday in May in each year, if not a legal holiday, and if a legal holiday,
then on the next regular business day following, at 10:00 a.m., or at such other
date and time as shall be fixed from time to time by the Board of Directors and
stated in the notice of meeting, at which the shareholders shall elect the
members of the Board of Directors subject to election, and transact such other
business as may properly be brought before the meeting.

     Section 3. Written notice of the annual meeting stating the time, place,
and purpose or purposes of the meeting shall be delivered not less than ten (10)
nor more than sixty (60)

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days before the date of the meeting, either personally or by mail, to each
shareholder of record entitled to vote at such meeting.

     Section 4. Only persons who are nominated in accordance with the following
procedures shall be eligible for election as Directors of the Corporation.
Nominations of persons for election to the Board of Directors may be made at any
annual meeting of shareholders (a) by or at the direction of the Board of
Directors (or any duly authorized committee thereof) or (b) by any shareholder
of the Corporation (i) who is a shareholder of record on the date of the giving
of the notice provided for in this Section 4 and on the record date for the
determination of shareholders entitled to vote at such annual meeting, and (ii)
who complies with the notice procedures set forth in this Section 4.

          In addition to any other applicable requirements, for a nomination to
be made by a shareholder, such shareholder must have given timely notice thereof
in proper written form to the Secretary of the Corporation.

          To be timely, a shareholder's notice to the Secretary must be
delivered to or mailed and received at the principal offices of the Corporation
not less than sixty (60) days nor more than ninety (90) days prior to the date
of the annual meeting of shareholders; provided, however, that in the event that
less than seventy (70) days' notice or prior public disclosure of the date of
the meeting is given to shareholders, notice by the shareholder to be timely
must be so received not later than the close of business on the tenth (10th) day
following the day on which such notice of the date of the annual meeting was
mailed or such public disclosure of the date of the annual meeting was made,
whichever first occurs.

          To be in proper written form, a shareholder's notice to the Secretary
must set forth (a) as to each person whom the shareholder proposes to nominate
for 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, (ii) the class or series and number of shares of capital stock of the
Corporation that are owned beneficially or of record by the person, and

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(iv) any other information relating to the person that would be required to be
disclosed in a proxy statement or other filings required to be made in
connection with solicitations of proxies for election of Directors pursuant to
Section 14 of the Securities Exchange Act of 1934, as amended (the "Exchange
Act"), and the rules and regulations promulgated thereunder; and (b) as to the
shareholder giving the notice (i) the name and record address of such
shareholder, (ii) the class or series and number of shares of capital stock of
the Corporation that are owned beneficially or of record by such shareholder,
(iii) a description of all arrangements or understandings between such
shareholder and each proposed nominee and any other person or persons (including
their names) pursuant to which the nomination(s) are to be made by such
shareholder, (iv) a representation that such shareholder intends to appear in
person or by proxy at the meeting to nominate the persons named in its notice,
and (v) any other information relating to such shareholder that would be
required to be disclosed in a proxy statement or other filings required to be
made in connection with solicitations of proxies for election of Directors
pursuant to Section 14 of the Exchange Act and the rules and regulations
promulgated thereunder. Such notice must be accompanied by a written consent of
each proposed nominee to being named as a nominee and to serve as a Director if
elected.

          No person shall be eligible for election as a Director of the
Corporation unless nominated in accordance with the procedures set forth in this
Section 4. If the chairman of the meeting determines that a nomination was not
made in accordance with the foregoing procedures, the chairman shall declare to
the meeting that the nomination was defective and such defective nomination
shall be disregarded.

          No business may be transacted at an annual meeting of shareholders,
other than business that is either (a) specified in the notice of meeting (or
any supplement thereto) given by or at the direction of the Board of Directors
(or any duly authorized committee thereof), (b) otherwise properly brought
before the annual meeting by or at the direction of the Board of Directors (or
any duly authorized committee thereof), or (c) otherwise properly brought before

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the annual meeting by any shareholder of the Corporation (i) who is a
shareholder of record on the date of the giving of the notice provided for in
this Section 4 and on the record date for the determination of shareholders
entitled to vote at such annual meeting and (ii) who complies with the notice
procedure set forth in this Section 4.

          In addition to any other applicable requirements, for business to be
properly brought before an annual meeting by a shareholder, such shareholder
must have given timely notice thereof in proper written form to the Secretary of
the Corporation.

          To be timely, a shareholder's notice to the Secretary must be
delivered to or mailed and received at the principal offices of the Corporation
not less than sixty (60) days nor more than ninety (90) days prior to the date
of the annual meeting of shareholders; provided, however, that in the event that
less than seventy (70) days' notice or prior public disclosure of the date of
the meeting is given to shareholders, notice by the shareholder to be timely
must be so received not later than the close of business on the tenth (10th) day
following the day on which such notice of the date of the annual meeting was
mailed or such public disclosure of the date of the annual meeting was made,
whichever first occurs.

          To be in proper written form, a shareholder's notice to the Secretary
must set forth as to each matter such shareholder 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 such shareholder, (iii) the
class or series and number of shares of capital stock of the Corporation that
are owned beneficially or of record by such shareholder, (iv) a description of
all arrangements or understandings between such shareholder and any other person
or persons (including their names) in connection with the proposal of such
business by such shareholder and any material interest of such shareholder in
such business, and (v) a representation that such shareholder intends to appear
in person or by proxy at the annual meeting to bring such business before the
meeting.

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          No business shall be conducted at the annual meeting of shareholders
except business brought before the annual meeting in accordance with the
procedures set forth in this Section 4, provided, however, that, once business
has been properly brought before the annual meeting in accordance with such
procedures, nothing in this Section 4 shall be deemed to preclude discussion by
any shareholder of any such business. If the chairman of an annual meeting
determines that business was not properly brought before the annual meeting in
accordance with the foregoing procedures, the chairman shall declare to the
meeting that the business was not properly brought before the meeting and such
business shall not be transacted.

                                   ARTICLE III

                        SPECIAL MEETINGS OF SHAREHOLDERS

     Section 1. Special meetings of shareholders for any purpose other than the
election of Directors may be held at such time and place within or without the
State of New Jersey as shall be stated in the notice of the meeting or in a duly
executed waiver of notice thereof.

     Section 2. Special meetings of shareholders, for any purpose or purposes,
unless otherwise prescribed by statute or by the certificate of incorporation,
may be called only by the Chairman of the Board of Directors, the President of
the Corporation, or the Board of Directors.

     Section 3. Written notice of a special meeting stating the time, place, and
purpose or purposes of the meeting for which the meeting is called, shall be
delivered not less than ten (10) nor more than sixty (60) days before the date
of the meeting, either personally or by mail, by or at the direction of the
President, the Secretary, or the officer or persons calling the meeting, to each
shareholder of record entitled to vote at such meeting.

     Section 4. Business transacted at any special meeting shall be confined to
the purpose or purposes stated in the notice thereof.

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     Section 5. No business shall be conducted at a special meeting of
shareholders except business brought before the special meeting in accordance
with the procedures set forth in Section 4 of Article II of these Bylaws,
provided, however, that, once business has been properly brought before the
special meeting in accordance with such procedures, nothing in that Section 4 of
Article II shall be deemed to preclude discussion by any shareholder of any such
business at such special meeting. If the chairman of a special meeting
determines that business was not properly brought before the special meeting in
accordance with the foregoing procedures, the chairman shall declare to the
meeting that the business was not properly brought before the meeting and such
business shall not be transacted.

                                   ARTICLE IV

                           QUORUM AND VOTING OF STOCK

     Section 1. The holders of a majority of the shares of stock issued and
outstanding and entitled to vote, represented in person or by proxy, shall
constitute a quorum at all meetings of the shareholders for the transaction of
business except as otherwise provided by statute or by the certificate of
incorporation. If, however, a quorum shall not be present or represented at any
meeting of the shareholders, the shareholders present in person or represented
by proxy shall have the power to adjourn the meeting from time to time, without
notice other than announcement at the meeting, until a quorum shall be present
or represented. At such adjourned meeting at which a quorum shall be present or
represented, any business may be transacted which might have been transacted at
the meeting as originally notified.

     Section 2. If a quorum is present, the affirmative vote of a majority of
the shares of stock represented at the meeting shall be the act of the
shareholders unless the vote of a greater number of shares of stock is required
by law or by the certificate of incorporation.

     Section 3. Each outstanding share of stock, having voting power, shall be
entitled to one vote on each matter submitted to a vote at a meeting of
shareholders, unless otherwise

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provided in the certificate of incorporation. A shareholder may vote either in
person or by proxy executed in writing by the shareholder or by his agent.

     In all elections for Directors, every shareholder entitled to vote, shall
have the right to vote, in person or by proxy, the number of shares of stock
owned by him, for as many persons as there are Directors to be elected and for
whose election he has a right to vote.

                                    ARTICLE V

                                    DIRECTORS

     Section 1. The number of directors which shall constitute the entire Board
of Directors shall be not less than three (3) nor more than ten (10). The exact
number of Directors within such maximum and minimum shall be determined from
time to time by resolution of the Board of Directors or by the shareholders at
an annual meeting or special meeting. Directors need not be residents of the
State of New Jersey nor shareholders of the Corporation. The first Board of
Directors shall hold office until the first annual meeting of shareholders.

     Section 2. The Board of Directors shall be classified with respect to the
duration of the term for which they severally hold office into three classes as
nearly equal in number as possible. Such classes shall originally consist of one
class of directors ("Class I") who shall be elected at the annual meeting of
shareholders held in 1991 for a term expiring at the annual meeting of
shareholders to be held in 1994; a second class of Directors ("Class II") who
shall be elected at the annual meeting of shareholders held in 1991 for a term
expiring at the annual meeting of shareholders to be held in 1993; and a third
class of Directors ("Class III") who shall be elected at the annual meeting of
shareholders held in 1991 for a term expiring at the annual meeting of
shareholders to be held in 1992. The Board of Directors shall increase or
decrease the number of Directors, in order to ensure that the three classes
shall be as nearly equal in number as possible; provided, however, that no
decrease shall have the effect of

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shortening the term of any incumbent Director. At each annual meeting of
shareholders beginning in 1992, the successors of the class of Directors whose
term expires at that meeting shall be, elected to hold office for a term
expiring at the annual meeting of shareholders held in the third year following
the year of their election. Provided a quorum is present, in any election of
Directors, the persons receiving a plurality of the votes cast, up to the number
of Directors to be elected in such election, shall be deemed elected.

     Section 3. Unless otherwise provided in the certificate of incorporation,
any directorship not filled at the annual meeting, any other vacancy, however
caused, occurring in the Board of Directors and newly created directorships
resulting from an increase in the authorized number of Directors may be filled
by the affirmative vote of a majority of the remaining Directors. Any Director
so elected by the Board of Directors shall hold office until the next succeeding
annual meeting of shareholders and until his successor shall have been elected
and qualified.

     Section 4. Any directorship not filled by the Board of Directors may be
filled by the shareholders at an annual meeting or at a special meeting of
shareholders called for that purpose.

     Section 5. The business affairs of the Corporation shall be managed by its
Board of Directors which may exercise all such powers of the Corporation and do
all such lawful acts and things as are not by statute or by the certificate of
incorporation or by these by-laws directed or required to be exercised or done
by the shareholders.

     Section 6. The Directors may keep the books and records of the Corporation,
except such as are required by law to be kept within the state, outside of the
State of New Jersey, at such place or places as they may from time to time
determine.

     Section 7. The Board of Directors, by the affirmative vote of a majority of
the Directors then in office, and irrespective of any personal interest of any
of its members, shall

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have authority to establish reasonable compensation of Directors for services to
the Corporation as Directors.

                                   ARTICLE VI

                       MEETINGS OF THE BOARD OF DIRECTORS

     Section 1. Meetings of the Board of Directors, regular or special, may be
held either within or without the State of New Jersey.

     Section 2. The first meeting of each newly elected Board of Directors shall
be held at such time and place as shall be fixed by the vote of the shareholders
at the annual meeting, and no notice of such meeting shall be necessary to the
newly elected Directors in order legally to constitute the meeting, provided a
quorum of Directors shall be present, or the Board of Directors may convene at
such place and time as shall be fixed by the consent in writing of all the
Directors.

     Section 3. Regular meetings of the Board of Directors may be held upon such
notice, or without notice, and at such time and at such place as shall from time
to time be determined by the Board of Directors.

     Section 4. Notice of the time and place of special meetings shall be given
to each Director at that Director's address as it is shown on the records of the
Corporation. Notice of such special meeting of the Board of Directors stating
the place, date and hour of the meeting shall be given to each Director either
(i) by mail not less than three (3) days before the date of the meeting, or (ii)
personally, by telephone, facsimile, telecopy, telegram, telex or other similar
means of communication on twenty-four (24) hours' notice, or on such shorter
notice as the person or persons calling such meeting may deem necessary or
appropriate in the circumstances. Any oral notice given personally or by
telephone may be communicated either to the Director or to a person at the
office of the Director whom the person giving the notice

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has reason to believe will promptly communicate it to the Director. Notice need
not be given to any other Director who signs a waiver of notice, whether before
or after the meeting.

     Section 5. Attendance by a Director at any meeting shall constitute a
waiver of notice of such meeting, except where a Director attends the meeting
for the express purpose of objecting 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 Board
of Directors need be specified in the notice or waiver of notice of such
meeting.

     Section 6. A majority of the Directors shall constitute a quorum for the
transaction of business unless a greater or lesser number is required by statute
or by the certificate of incorporation. The act 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, unless the act of a greater or lesser number is required by
statute or by the certificate of incorporation. If a quorum shall not be present
at any meeting of Directors, the Directors present thereat may adjourn the
meeting, without notice other than announcement at the meeting, until such time
as a quorum shall be present.

     Section 7. Unless otherwise provided by the certificate of incorporation,
any action required or permitted to be taken at a meeting of the Board of
Directors, or any committee thereof, shall be deemed to be the action of the
Board of Directors or of a committee thereof, if all Directors or committee
members, as the case may be, execute either before or after the action is taken,
a written consent thereto, and the consent is filed with the records of the
Corporation.

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                                   ARTICLE VII

                                   COMMITTEES

     Section 1. The Board of Directors, by resolution adopted by a majority of
the number of Directors fixed by the by-laws or otherwise, may designate one or
more Directors to constitute an executive committee, and one or more other
committees, which committee(s), to the extent provided in such resolution, shall
have and exercise all of the authority of the Board of Directors in the
management of the Corporation, except as otherwise required by law. Vacancies in
the membership of the committee(s) shall be filled by the Board of Directors at
a regular or special meeting of the Board of Directors. The executive committee
and such other committee(s)shall keep regular minutes of its proceedings and
report the same to the Board when required.

                                  ARTICLE VIII

                                     NOTICES

     Section 1. Whenever, under the provisions of the statutes or of the
certificate of incorporation or of these by-laws, notice is required to be given
to any shareholder, it shall not be construed to mean personal notice, but such
notice may be given in writing, by mail, addressed to such shareholder, at such
shareholder's address as it appears on the records of the Corporation, with
postage thereon prepaid, and such notice shall be deemed to be given at the time
when the same shall be deposited in the United States mail.

     Section 2. Whenever any notice whatever is required to be given under the
provisions of the statutes or under the provisions of the certificate of
incorporation or these by-laws, a waiver thereof in writing signed by the person
or persons entitled to such notice, whether before or after the time stated
therein, shall be deemed equivalent to the giving of such notice.

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                                   ARTICLE IX

                                    OFFICERS

     Section 1. The officers of the Corporation shall be chosen by the Board of
Directors and may include a chairman of the board, a President, a Vice
President, a Secretary, a Treasurer and such additional officers as may be
designated by the Board of Directors from time to time.

     Section 2. The Board of Directors at its first meeting after each annual
meeting of shareholders shall choose a President, a Secretary and a Treasurer,
none of whom need be a member of the Board of Directors.

     Section 3. The Board of Directors may appoint such other officers and
agents as it shall deem necessary who shall hold their offices for such terms
and shall exercise such powers and perform such duties as shall be determined
from time to time by the Board of Directors.

     Section 4. The salaries of all officers and agents of the Corporation shall
be fixed, from time to time, by the Board of Directors or a committee thereof.

     Section 5. The officers of the Corporation shall hold office until their
successors are chosen and qualified. Any officer elected or appointed by the
Board or Directors may be removed at any time by the affirmative vote of a
majority of the Board of Directors. Any vacancy occurring in any office of the
Corporation shall be filled by the Board of Directors.

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                                  THE CHAIRMAN

     Section 1. The Chairman, if one is designated by the Board of Directors,
shall preside at all meetings of the shareholders and the Board of Directors,
and shall perform such other duties and have such other powers as the Board of
Directors may from time to time prescribe.

                                  THE PRESIDENT

     Section 1. The President shall be the chief executive officer of the
Corporation and shall have general management of the business of the
Corporation. In addition, the President, in the absence or inability of the
Chairman or if no Chairman is designated by the Board, shall perform the duties
and exercise the powers of the Chairman, and shall perform such other duties and
have such other powers as the Board of Directors may from time to time
prescribe.

     Section 2. The President shall execute bonds, mortgages and other contracts
requiring a seal, under the seat of the Corporation, except where required or
permitted by law to be otherwise signed and executed and except where the
signing and execution thereof shall be expressly delegated by the Board of
Directors to some other officer or agent of the Corporation.

                               THE VICE PRESIDENT

     Section 1. The Vice President, or if there shall be more than one, the Vice
Presidents in the order determined by the Board of Directors, shall, in the
absence or disability of the President, perform the duties and exercise the
powers of the President and shall perform such other duties and have such other
powers as the Board of Directors may from time to time prescribe.

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                    THE SECRETARY AND ASSISTANT SECRETARIES

     Section 1. The Secretary shall attend all meetings of the Board of
Directors and all meetings of the shareholders and record all the proceedings of
the meetings of the Corporation and of the Board of Directors in a book to be
kept for that purpose and shall perform like duties for the standing committees
when required. He shall give, or cause to be given, notice of all meetings of
the shareholders and special meetings of the Board of Directors, and shall
perform such other duties as may be prescribed by the Board of Directors or the
President, under whose supervision he shall be. He shall have custody of the
corporate seal of the Corporation and he, or an Assistant Secretary, shall have
authority to affix the same to any instrument requiring it and when so affixed,
it may be attested by his signature or by the signature of such Assistant
Secretary. The Board of Directors may give general authority to any other
officer to affix the seal of the Corporation and to attest the affixing by his
signature.

     Section 2. The Assistant Secretary, or if there be more than one, the
Assistant Secretaries in the order determined by the Board of Directors, shall,
in the absence or disability of the Secretary, perform the duties and exercise
the powers of the Secretary and shall perform such other duties and have such
other powers as the Board of Directors may from time to time prescribe.

                     THE TREASURER AND ASSISTANT TREASURERS

     Section 1. The Treasurer shall have the custody of the corporate funds and
securities and 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 from time to time by the Board of
Directors.

     Section 2. The Treasurer shall disburse the funds of the Corporation as may
be ordered by the Board of Directors, taking proper vouchers for such
disbursements, and shall

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render to the President and the Board of Directors, at its regular meetings, or
when the Board of Directors so requires, an account of all his transactions as
Treasurer and of the financial condition of the Corporation.

     Section 3. If required by the Board of Directors, the Treasurer shall give
the Corporation a bond in such sum and with such surety or sureties as shall be
satisfactory to the Board of Directors for the faithful performance of the
duties of his office and for the restoration to the Corporation, in case of his
death, resignation, retirement or removal from office, of all books, papers,
vouchers, money and other property of whatever kind in his possession or under
his control belonging to the Corporation.

     Section 4. The Assistant Treasurer, or, if there shall be more than one,
the Assistant Treasurers in the order determined by the Board of Directors,
shall, in the absence or disability of the Treasurer, perform the duties and
exercise the powers of the Treasurer and shall perform such other duties and
have such other powers as the Board of Directors may from time to time
prescribe.

                                    ARTICLE X

                             CERTIFICATES FOR SHARES

     Section 1. The shares of the Corporation shall be represented by
certificates signed by the Chairman or Vice Chairman of the Board of Directors,
or the President or Vice President and by the Treasurer or an Assistant
Treasurer, or the Secretary or an Assistant Secretary of the Corporation, and
may be sealed with the seal of the Corporation or a facsimile thereof.

     When the Corporation is authorized to issue shares of more than one class,
there shall be set forth upon the face or back of the certificate, or the
certificate shall have a statement that the Corporation will furnish to any
shareholder upon request and without charge, a full statement of the
designations, preferences, limitations and relative rights of the

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shares of each class authorized to be issued and, if the Corporation is
authorized to issue any preferred or special class in series, the variations in
the relative rights and preferences between the shares of each such series so
far as the same have been fixed and determined and the authority of the Board of
Directors to fix and determine the relative rights and preferences of subsequent
series.

     Section 2. The signatures of the officers of the Corporation upon a
certificate may be facsimiles if the certificate is countersigned by a transfer
agent, or registered by a registrar, other than the Corporation itself or an
employee of the Corporation. In case any officer who has signed or whose
facsimile signature has been placed upon such certificate shall have ceased to
be such officer before such certificate is issued, it may be issued by the
Corporation with the same effect as if he were such officer at the date of its
issue.

                                LOST CERTIFICATES

     Section 3. The Board of Directors may direct a new certificate to be issued
in place of any certificate theretofore issued by the Corporation alleged to
have been lost or destroyed. When authorizing such issue of a new certificate,
the Board of Directors, in its discretion and as a condition precedent to the
issuance thereof, may prescribe such terms and conditions as it deems expedient,
and may require such indemnities as it deems adequate, to protect the
Corporation from any claim that may be made against it with respect to any such
certificate alleged to have been lost or destroyed.

                               TRANSFERS OF SHARES

     Section 4. Upon surrender to the Corporation or the transfer agent of the
Corporation of a certificate representing shares duly endorsed or accompanied by
proper evidence of succession, assignment or authority to transfer, a new
certificate shall be issued to the person entitled thereto, and the old
certificate canceled and the transaction recorded upon the books of the
Corporation.

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                            CLOSING OF TRANSFER BOOKS

     Section 5 For the purpose of determining shareholders entitled to notice of
or to vote at any meeting of shareholders or any adjournment thereof or entitled
to receive payment of any dividend or allotment of any right, or entitled to
give a written consent to any action without a meeting, or in order to make a
determination of shareholders for any other proper purpose, the Board of
Directors may provide that the stock transfer books shall be closed for a stated
period but not to exceed, in any case, sixty (60) days. If the stock transfer
books shall be closed for the purpose of determining shareholders entitled to
notice of or to vote at a meeting of shareholders, such books shall be closed
for at least ten (10) days immediately preceding such meeting. If the stock
transfer book shall be closed for the purpose of determining shareholders
entitled to give a written consent to any action without a meeting, such books
may not be closed for more than sixty (60) days before the date fixed for
tabulation of consents or if no date has been fixed for tabulation, the books
may not be closed for more than sixty (60) days before the last day on which
consents received may be counted. In lieu of closing the stock transfer books,
the Board of Directors may fix in advance a date as the record date for any such
determination of shareholders, such date in any case to be not more than sixty
(60) days and, in case of a meeting of shareholders, not less than ten (10) days
prior to the date on which the particular action, requiring such determination
of shareholders, is to be taken and, in case of determining shareholders
entitled to give a written consent the record date may not be more than sixty
(60) days before the date fixed for tabulation of the consents or, if no date
has been fixed for the tabulation, more than sixty (60) days before the last day
on which consents may be counted. If the stock transfer books are not closed and
no record date is fixed, the record date for a shareholders' meeting shall be
the close of business on the day next preceding the day on which notice is
given, or, if no notice is given, the day next preceding the day on which the
meeting is held; and the record date for determining shareholders for any other

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purpose shall be at the close of business on the day on which the resolution of
the Board relating thereto is adopted. When a determination of shareholders of
record for a shareholders' meeting has been made as provided in this section,
such determination shall apply to any adjournment thereof unless the board fixes
a new record date for the adjourned meeting.

                             REGISTERED SHAREHOLDERS

     Section 6 The Corporation shall be entitled to recognize the exclusive
right of a person registered on its books as the owner of shares to receive
dividends, and to vote as such owner, and to hold liable for calls and
assessments a person registered on its books as the owner of shares, and shall
not be bound to recognize any equitable or other claim to or interest in such
share or shares on the part of any other person, whether or not it shall have
express or other notice thereof, except as otherwise provided by the laws of New
Jersey.

                              LIST OF SHAREHOLDERS

     Section 7 The officer or agent having charge of the transfer books for
shares shall make, and certify a complete list of the shareholders entitled to
vote at a shareholders' meeting, or adjournment thereof, arranged in
alphabetical order within each class, series, or group of shareholders
maintained by the Corporation for convenience of reference, with the address of,
and the number of shares held by each shareholder, which list shall be produced
and kept open at the time and place of the meeting and shall be subject to the
inspection of any shareholder during the whole time of the meeting. Such list
shall be prima facie evidence as to who are the shareholders entitled to examine
         ----- -----
such list or to vote at any meeting of the shareholders.

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                                   ARTICLE XI

                               GENERAL PROVISIONS

                                    DIVIDENDS

     Section 1. Subject to the provisions of the certificate of incorporation
relating thereto, if any, dividends may be declared by the Board of Directors at
any regular or special meeting, pursuant to law. Dividends may be paid by the
Corporation in cash, in its bonds, in its own shares or other property including
the shares or bonds of other corporations subject to any provisions of law and
of the certificate of incorporation.

     Section 2. Before payment of any dividend, there may be set aside out of
any funds of the Corporation available for dividends such sum or sums as the
Directors from time to time, in their absolute discretion, think proper as a
reserve fund to meet contingencies, or for equalizing dividends, or for
repairing or maintaining any property of the Corporation, or for such other
purpose as the Directors shall think conducive to the interest of the
Corporation, and the Directors may modify or abolish any such reserve in the
manner in which it was created.

                                     CHECKS

         Section 3. All checks or demands for money and notes of the Corporation
     shall be signed by such officer or officers or such other person or persons
     as the Board of Directors may from time to time designate.

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                                   FISCAL YEAR

         Section 4. The fiscal year of the Corporation shall be fixed by
     resolution of the Board of Directors.
                                      SEAL

         Section 5. The corporate seal shall have inscribed thereon the name of
     the Corporation, the year of its organization and the words "Corporate
     Seal, New Jersey." The seal may be used by causing it or a facsimile
     thereof to be impressed or affixed or in any manner reproduced.

                                   ARTICLE XII

                                   AMENDMENTS

     Section 1. 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 Board of
Directors at any regular or special meeting of the Board, subject to any
provision in the certificate of incorporation reserving to the shareholders the
power to adopt, amend, or repeal by-laws, but the shareholders may alter or
repeal any by-laws made by the Board and may adopt new by-laws. The shareholders
or these by-laws may prescribe that any by-law made by the shareholders shall
not be altered or repealed by the Board without the approval of the
shareholders.

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<PAGE>

                                  ARTICLE XIII
               INDEMNIFICATION OF OFFICERS, DIRECTORS, EMPLOYEES,
              MEMBERS OF THE SCIENTIFIC ADVISORY BOARD AND AGENTS

     Section 1. The Corporation shall indemnify any 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 (other than an action by or in the right of the Corporation) by
reason of the fact that he is or was a Director, officer, employee, a member of
the Scientific Advisory Board 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 expenses (including attorneys' fees), judgments, fines and amounts paid
in settlement actually and reasonably incurred by him in connection with the
defense or settlement of such action, suit or proceeding if he acted in good
faith and in a manner he reasonably believed to be in or not opposed to the best
interests of the Corporation and, with respect to any criminal action or
proceeding, had no reasonable cause to believe his conduct was unlawful. The
termination of any action, suit or proceeding by judgment, order, settlement,
conviction, or upon a plea of nolo contendere or its equivalent, shall not, or
                              ---- ----------
itself, create a presumption that the person did not act in good faith and in a
manner which he reasonably believed to be in or not opposed to the best
interests of the Corporation, and with respect to any criminal action or
proceeding, had reasonable cause to believe that his conduct was unlawful.

     Section 2. The Corporation shall indemnify any person who was or is a party
or is threatened to be made a party to any threatened, pending or completed
action or suit by or in the right of the Corporation to procure a judgment in
its favor by reason of the fact that he is or was a Director, officer, employee,
a Member of the Corporation's Scientific Advisory Board 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

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<PAGE>

other enterprise against expenses (including attorneys' fees) actually and
reasonably incurred by him in connection with the defense or settlement of such
action or suit if he acted in good faith and in a manner he reasonably believed
to be in or not opposed to the best interests of the Corporation, except that no
indemnification shall be provided in respect of any claim, issue or matter as to
which such person shall have been adjudged to be liable to the Corporation
unless and only to the extent that the court in which such action or suit was
brought shall determine upon application that, despite the adjudication of
liability but in view of all the circumstances of the case, such person is
fairly and reasonably entitled to indemnity for such expenses which such court
shall deem proper.

     Section 3. To the extent that such director, officer, employee, a Member of
the Corporation's Scientific Advisory Board or agent has been successful on the
merits or otherwise in defense of any action, suit or proceeding referred to in
Section 1 and 2 of this Article XIII, or in the defense of any claim, issue or
matter therein, he shall be indemnified against expenses (including attorneys'
fees) actually and reasonably incurred by him in connection therewith.

     Section 4. Any indemnification under Section 1 or 2 of this Article XIII
(unless ordered by a court) shall be made by the Corporation only as authorized
in the specific case upon a determination that indemnification of the Director,
officer, employee, a Member of this Corporation's Scientific Advisory Board or
agent is proper in the circumstances because he has met the applicable standard
of conduct set forth in Section 1 or 2, as the case may be. Such determination
shall be made (i) by the Board of Directors by a majority vote of a quorum
consisting of Directors who were not parties to such action, suit or proceeding,
or (ii) if such a quorum is not obtainable, or, even if obtainable, a quorum of
disinterested Directors so directs, by independent legal counsel in a written
opinion, or (iii) by the shareholders of the Corporation.

                                       22
<PAGE>

     Section 5. Expenses incurred in defending a civil or criminal action, suit
or proceeding may be paid by this Corporation in advance of the final
disposition of such action, suit or proceeding as authorized by the Board of
Directors, in the specific case upon receipt of an undertaking by or on behalf
of the Director, officer, employee, Member of the Corporation's Scientific
Advisory Board or agent to repay such amount unless it shall ultimately be
determined that he is entitled to be indemnified by this Corporation as
authorized in this Article XIII.

     Section 6. The indemnification provided by this Article XIII shall not be
deemed exclusive of any other rights to which those seeking indemnification may
be entitled under any other by-law, agreement, vote of shareholders or
disinterested Directors or otherwise, both as to action in his official capacity
and as to action in another capacity while holding such office, and shall
continue as to a person who has ceased to be a Director, officer, employee,
Member of the Corporation's Scientific Advisory Board or agent and shall inure
to the benefit of the heirs, executors and administrators of such a person.

     Section 7. The Corporation, when authorized by the Board of Directors,
shall purchase and maintain insurance on behalf of the person who is or was a
Director, officer, employee, Member of the Corporation's Scientific Advisory
Board or agent of the Corporation, or is or was serving at the request of this
Corporation as a Director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise against any liability
asserted against him and incurred by him in such capacity or arising out of his
status as such, whether or not the Corporation would have the power to indemnify
him against such liability under the provisions of this Article XIII.

                                       23
<PAGE>

                                   ARTICLE XIV

                                 WRITTEN CONSENT

     Section 1. Unless otherwise provided in the certificate of incorporation,
any action required by this chapter to be taken at any annual or special meeting
of shareholders of the Corporation, or any action that may be taken at any
annual or special meeting of such shareholders, may be taken without a meeting,
without prior notice, and without a vote if a consent in writing, setting forth
the action so taken, is signed by the holders of outstanding shares having not
less than the minimum number of votes that would be necessary to authorize or
take such action at a meeting at which all shares entitled to vote thereon were
present and voted.

     Section 2. Prompt notice of the taking of the corporate action without a
meeting by less than unanimous written consent shall be given to those
shareholders who have not consented in writing. If the action which is consented
to is such as would have required the filing of a certificate under any section
of the New Jersey Business Corporation Act (the "NJBCA") had the action been
voted on by shareholders at a meeting thereof, then the certificate filed under
such section shall state, in lieu of any statement required by such section
concerning any vote of shareholders, that written notice and written consent
have been given as provided in Section 14A:5-6 of the NJBCA.

     Section 3. In order that the Corporation may determine the shareholders
entitled to consent to corporate action in writing without a meeting, the Board
of Directors may fix a record date, which record date shall not precede the date
upon which the resolution fixing the record date is adopted by the Board of
Directors, and which date shall not be more than ten (10) days after the date
upon which the resolution fixing the record date is adopted by the Board of
Directors. Any shareholder of record seeking to have the shareholders authorize
or take corporate action by written consent shall, by written notice to the
secretary, request the Board of Directors to fix a record date. The Board of
Directors shall promptly, but in all

                                       24
<PAGE>

events within ten (10) days after the date on which such a request is received,
adopt a resolution fixing the record date. If no record date has been fixed by
the Board of Directors within ten (10) days of the date on which such a request
is received, the record date for determining shareholders entitled to consent to
corporate action in writing without a meeting, when no prior action by the Board
of Directors is required by applicable law, shall be the first date on which a
signed written consent setting forth the action taken or proposed to be taken is
delivered to the Corporation by delivery to its registered office in the State
of New Jersey, its principal place of business or an officer or agent of the
Corporation having custody of the book in which proceedings of meetings of
shareholders are recorded, to the attention of the Secretary of the Corporation.
Delivery shall be by hand or by certified or registered mail, return receipt
requested. If no record date has been fixed by the Board of Directors and prior
action by the Board of Directors is required by applicable law, the record date
for determining shareholders entitled to consent to corporate action in writing
without a meeting shall be at the close of business on the date on which the
Board of Directors adopts the resolution taking such prior action.

     Section 4. In the event of the delivery to the Corporation of a written
consent or consents purporting to authorize or take corporate action and/or
related revocations (each such written consent and any revocation thereof is
referred to in this Section 4 as a "Consent"), the Secretary of the Corporation
shall provide for the safekeeping of such Consents and shall as soon as
practicable thereafter conduct such reasonable investigation as he deems
necessary or appropriate for the purpose of ascertaining the validity of such
Consents and all matters incident thereto, including, without limitation,
whether the holders of shares having the requisite voting power to authorize or
take the action specified in the Consents have given consents. No consent to
corporate action in writing without a meeting shall be effective unless
delivered to the Corporation within sixty (60) days following the record date
relating thereto fixed pursuant to Section 3 above.

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