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                                                                   Exhibit 3.1

                           FOURTH AMENDED AND RESTATED

                          CERTIFICATE OF INCORPORATION

                                       OF

                            DOV PHARMACEUTICAL, INC.

         DOV Pharmaceutical, Inc., a corporation organized and existing under
the laws of the State of Delaware (the "Corporation"), hereby certifies as
follows:

         1. The name of the Corporation is DOV Pharmaceutical, Inc. The date of
the filing of its original Certificate of Incorporation with the Delaware
Secretary of State was November 2, 2000 under the name DOV Pharmaceutical, Inc
and was amended and restated by the Corporation's Amended and Restated
Certificate of Incorporation filed with the Delaware Secretary of State on
November 20, 2000. The Amended and Restated Certificate of Incorporation was
amended and restated by the Corporation's Second Amended and Restated
Certificate of Incorporation filed with the Delaware Secretary of State on
August 30, 2001, as amended by the First Certificate of Amendment to the Second
Amended and Restated Certificate of Incorporation filed with the Delaware
Secretary of State on April 4, 2002. The Second Amended and Restated Certificate
of Incorporation, as amended, was amended and restated by the Corporation's
Third Amended and Restated Certificate of Incorporation filed with the Delaware
Secretary of State on April 25, 2002 (the "Third Amended and Restated
Certificate").

         2. This Fourth Amended and Restated Certificate of Incorporation (the
"Certificate") amends, restates and integrates the provisions of the Third
Amended and Restated Certificate and was duly adopted in accordance with the
provisions of Sections 242 and 245 of the Delaware General Corporation Law (the
"DGCL").

         3. The text of the Third Amended and Restated Certificate is hereby
amended and restated in its entirety to provide as herein set forth in full.

                                   ARTICLE I

         The name of the Corporation is DOV Pharmaceutical, Inc.

                                   ARTICLE II

         The address of the Corporation's registered office in the State of
Delaware is c/o The Corporation Trust Company, 1209 Orange Street in the City of
Wilmington, County of New Castle. The name of its registered agent at such
address is The Corporation Trust Company.


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                                  ARTICLE III

         The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the DGCL.

                                   ARTICLE IV

                                  CAPITAL STOCK

         The total number of shares of capital stock which the Corporation shall
have authority to issue is Sixty-Six Million, Nine Hundred Five Thousand
(66,905,000) shares, of which (i) Sixty Million (60,000,000) shares shall be a
class designated as common stock, par value $.0001 per share (the "Common
Stock"), (ii) Three Hundred Fifty Four Thousand Six Hundred Forty-Three
(354,643) shares shall be designated as series B preferred stock, par value
$1.00 per share (the "Series B Preferred") and (iii) Six Million Five Hundred
Fifty Thousand Three Hundred Fifty-Seven (6,550,357) shares shall be a class
designated as undesignated preferred stock, par value $1.00 per share (the
"Undesignated Preferred Stock", and together with the Series B Preferred, the
"Preferred Stock").

         The number of authorized shares of the class of Undesignated Preferred
Stock may from time to time be increased or decreased (but not below the number
of shares outstanding) by the affirmative vote of the holders of a majority of
the outstanding shares of Common Stock entitled to vote, without a vote of the
holders of the Series B Preferred or any class or series of the Undesignated
Preferred Stock (except as otherwise provided in any certificate of designations
of any series of Undesignated Preferred Stock).

         The powers, preferences and rights of, and the qualifications,
limitations and restrictions upon, each class or series of stock shall be
determined in accordance with, or as set forth below in, this Article IV.


                                 A. COMMON STOCK

         Subject to all the rights, powers and preferences of the Preferred
Stock and except as provided by law or in this Article IV (or in any certificate
of designations of any series of Undesignated Preferred Stock):

                  (a) the holders of the Common Stock shall have the exclusive
right to vote for the election of directors of the Corporation (the "Directors")
and on all other matters requiring stockholder action, each outstanding share
entitling the holder thereof to one vote on each matter properly submitted to
the stockholders of the Corporation for their vote; PROVIDED, HOWEVER, that,
except as otherwise required by law, holders of Common Stock, as such, shall not
be entitled to vote on any amendment to this Certificate (or on any amendment to
a certificate of designations of any series of Undesignated Preferred Stock)
that alters or changes the powers, preferences, rights or other terms of one or
more outstanding classes or series of Preferred Stock if the holders of such
affected series are entitled to vote, either separately or together with the
holders of one or more other such series, on such amendment pursuant to this
Certificate (or pursuant to a


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certificate of designations of any series of Undesignated Preferred Stock) or
pursuant to the DGCL;

                  (b) dividends may be declared and paid or set apart for
payment upon the Common Stock out of any assets or funds of the Corporation
legally available for the payment of dividends, but only when and as declared by
the Board of the Corporation (the "Board") or any authorized committee thereof;
and

                  (c) upon the voluntary or involuntary liquidation, dissolution
or winding up of the Corporation, the net assets of the Corporation shall be
distributed pro rata to the holders of the Common Stock.

                           B. SERIES B PREFERRED STOCK

         1. DESIGNATION AND NUMBER OF SHARES. The shares of such series shall be
designated as "Series B Preferred Stock" ("Series B Preferred"). The number of
shares constituting Series B Preferred shall be 354,643.

         2. VOTING RIGHTS. The holders of Series B Preferred Stock shall have
the following voting rights:

                  (a) So long as the holders of Series B Preferred Stock own at
least 10% of the capital stock of the Corporation, the holders of Series B
Preferred Stock, as a class, shall be entitled to nominate and elect one
director to the Board. Such director shall be elected by the affirmative vote of
a majority of the shares of Series B Preferred Stock cast at a special meeting
of such holders called for that purpose, and any vacancy of such Board seat
shall be filled by a vote of such holders. This director shall have votes equal
to 9.9% of all votes that may be cast at a meeting of the Board (including the
vote of the director elected by the holders of Series B Preferred Stock).

                  (b) Except as provided herein or by applicable law, holders of
Series B Preferred shall have no voting power and shall not be entitled to
receive notice of any meetings of the Corporation's stockholders. Further,
except as provided herein or by applicable law, the consent of the holders of
Series B Preferred shall not be required to authorize or take any corporate
action. In cases where a provision of law expressly confers the right to vote
upon the holders of Series B Preferred, the holders of Series B Preferred shall
vote separately as a class and each holder of Series B Preferred shall be
entitled to one vote for each full share of Series B Preferred held by such
holder.

         3. CONVERSION RIGHTS. Each holder of Series B Preferred shall have
conversion rights as follows (the "Series B Conversion Right"):

                  (a) SERIES B CONVERSION RATE. Each share of Series B Preferred
shall, initially, convert into one (1) share of Common Stock; PROVIDED, that the
rate at which each share of Series B Preferred shall convert into Common Stock
shall be adjusted from time to time as


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provided in this Section 3 (such conversion rate, as adjusted as of the relevant
time of determination, the "Series B Conversion Rate").

         (b) OPTIONAL CONVERSION. At any time, upon the affirmative vote of the
holders of 75% or more of the Series B Preferred then outstanding (such
consenting holders, collectively, the "Series B Consenting Holders"), all shares
of Series B Preferred then outstanding shall be convertible, without payment of
any additional consideration by the holder thereof, into fully paid and
non-assessable shares of Common Stock at the then applicable Series B Conversion
Rate.

         (c) MECHANICS OF CONVERSION. In order to exercise the Series B
Conversion Right pursuant to Section 3(b), the Series B Consenting Holders shall
collectively provide written notice (the "Series B Conversion Notice") to the
Corporation at its principal place of business, setting forth (i) such holders'
intent to exercise the Series B Conversion Right, and (ii) the proposed date for
such exercise (the "Series B Conversion Date"). Promptly (but in no event more
than two (2) business days) following its receipt of the Series B Conversion
Notice, the Corporation shall forward a copy of the Series B Conversion Notice
to each holder of Series B Preferred who or which has not consented to the
exercise of the Series B Conversion Right by the Series B Conversion Notice, at
such holder's address as set forth in the records of the Corporation. On the
Series B Conversion Date, each holder of Series B Preferred shall tender to the
Corporation for cancellation certificates (collectively, the "Tendered
Certificate") representing all of such holder's shares of Series B Preferred,
and the Corporation shall, substantially concurrently, against receipt of such
Tendered Certificate, cause to be delivered to such holder a number of shares of
Common Stock (or other securities or property, as the case may be, pursuant to
Section 4(a)) as calculated pursuant to Section 3(b) above. Each such holder and
the Corporation shall take all other necessary or appropriate actions in
connection with or to effect the relevant exercise of the Series B Conversion
Right. From and after the Series B Conversion Date, shares of Series B Preferred
shall no longer be deemed to be outstanding and all rights with respect to such
Series B Preferred, including, without limitation, the rights, if any, to
receive notices and to vote, shall forthwith cease and terminate, except solely
the right to receive the shares of Common Stock (or other securities or
property, as the case may be, pursuant to Section 4(a)) issuable upon conversion
thereof.

         (d) CERTAIN ADJUSTMENTS

                           (i) ADJUSTMENT FOR COMMON STOCK DIVIDENDS AND
DISTRIBUTIONS. If, at any time after April 4, 2002 (the "Filing Time"), the
Corporation makes, or fixes a record date for the determination of holders of
Common Stock entitled to receive a dividend or other distribution payable in
additional shares of Common Stock, in each such event the Series B Conversion
Rate that is then in effect shall be proportionately adjusted in respect of such
dividend or distribution as of the time of such issuance or, in the event such
record date is fixed, as of the close of business on such record date; PROVIDED,
HOWEVER, that if such record date is fixed and such dividend is not fully paid
or if such distribution is not fully made on the date fixed therefor, the Series
B Conversion Rate shall be recomputed accordingly as of the close of business on
such record date and thereafter the Series B Conversion Rate shall be adjusted
pursuant to this Section 3(d)(i) to reflect the actual payment of such dividend
or distribution.


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                           (ii) ADJUSTMENTS FOR STOCK SPLITS, STOCK SUBDIVISIONS
AND COMBINATIONS. If, at any time after the Filing Time, the Corporation
subdivides (including, without limitation, a stock split) or combines
(including, without limitation, a reverse stock split) the Common Stock, the
Series B Conversion Rate in effect immediately prior to such event shall be
proportionately adjusted in respect of such subdivision or combination. Any
adjustment under this Section 3(d)(ii) shall become effective at the close of
business on the date the subdivision or combination becomes effective.

         4.       MISCELLANEOUS PROVISIONS.

                  (a) ADJUSTMENTS FOR RECLASSIFICATION, REORGANIZATION AND
CONSOLIDATION. In case of (A) any reclassification, reorganization,
recapitalization, change, exchange or conversion of securities of the class
issuable upon conversion of the Series B Preferred (other than a change in par
value, or from par value to no par value) into other securities or property of
the Corporation or another person or entity, or (B) any merger or consolidation
of the Corporation with or into another entity (other than a merger or
consolidation with another entity in which the Corporation is the acquiring and
the surviving entity and that does not result in any reclassification or change
of outstanding securities issuable upon conversion of the Series B Preferred),
or (C) any sale of all or substantially all the assets of the Corporation, each
holder of shares of Series B Preferred shall have the right to receive, in lieu
of the securities otherwise issuable upon the conversion of its shares of Series
B Preferred, the kind and amount of shares of stock and/or other securities,
money and property receivable upon such reclassification, reorganization,
recapitalization, change, merger, consolidation, exchange, conversion or sale by
a holder of the maximum number of shares of Common Stock (or other securities or
property, as the case may be) into which such shares of Series B Preferred could
have been converted immediately prior to such reclassification, reorganization,
recapitalization, change, merger, consolidation, exchange, conversion or sale,
all subject to further adjustment as provided herein or with respect to such
other securities or property by the terms thereof. The provisions of this
Section 4(a) shall similarly attach to successive reclassifications,
reorganizations, recapitalizations, changes, mergers, consolidations, exchanges,
conversions and sales. In any such case, appropriate adjustment shall be made in
the application of the provisions of Section 3 hereof with respect to the rights
of the holders of the Series B Preferred to the end that the provisions of
Sections 3 and 4(b) hereof (including adjustment of the Series B Conversion Rate
then in effect and the number of shares or other property obtainable upon
conversion of the Series B Preferred) shall be applicable after that event as
nearly equivalent as may be practicable.

                  (b) OTHER DISTRIBUTIONS. In the event the Corporation provides
the holders of its Common Stock with consideration that is not otherwise
addressed in Sections 3 or 4(a) hereof (including, without limitation, declaring
a distribution payable in securities of other persons, providing evidences of
indebtedness issued by the Corporation or other persons, assets, cash, but
excluding cash dividends declared out of retained earnings), then, in each such
case, the holders of the Series B Preferred shall be entitled to a pro rata
share of any such distribution as though they were the holders of the number of
shares of Common Stock of the Corporation into which their shares of Series B
Preferred would be convertible as of the record date fixed for the determination
of the holders of Common Stock of the Corporation entitled to receive such
distribution.

                  (c) NO FRACTIONAL SHARES. No fractional shares shall be issued
upon the conversion of any share or shares of the Series B Preferred, but in
lieu of such fractional shares,


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the Corporation shall make a cash payment therefore based on the Series B
Conversion Rate on the Conversion Date, as reasonably determined in good faith
by the Board of Directors.

                  (d) NOTICE OF ADJUSTMENT. Upon the occurrence of each
adjustment or readjustment of the Series B Conversion Rate pursuant to Section 3
hereof, the Corporation, at its expense, shall promptly compute such adjustment
or readjustment in accordance with the terms hereof and prepare and furnish to
each holder of shares of Series B Preferred a certificate setting forth such
adjustment or readjustment and showing in detail the facts upon which such
adjustment or readjustment is based. The Corporation shall, upon the written
request at any time of any holder of Series B Preferred, furnish or cause to be
furnished to such holder a like certificate setting forth (i) such adjustment or
readjustment, (ii) the Series B Conversion Rate at the time in effect, and (iii)
the number of shares of Common Stock and/or the amount, if any, of other
property which at the time would be received upon the conversion of a share of
Series B Preferred.

                  (e) RESERVATION OF SHARES. The Corporation shall at all times
reserve and keep available out of its authorized but unissued shares of Common
Stock, solely for the purposes of effecting the conversion of the shares of the
Series B Preferred, such number of its shares of Common Stock as shall from time
to time be sufficient to effect the conversion of all outstanding shares of the
Series B Preferred. If at any time the number of authorized but unissued shares
of Common Stock not otherwise reserved for issuance shall not be sufficient to
effect the conversion of all then outstanding shares of the Series B Preferred,
the Corporation shall take such corporate action as may, in the opinion of its
counsel, be necessary to increase its authorized but unissued shares of Common
Stock to such number of shares as shall be sufficient for such purposes,
including without limitation, engaging in best efforts to obtain the requisite
stockholder approval of any necessary amendment to its Certificate of
Incorporation.

                  (f) NOTICE OF EVENTS: Any notice required by the provisions
hereof to be given to the holders of shares of Series B Preferred shall be given
in writing and shall be deemed to have been given on the date of service if
served personally on the party to whom notice is to be given, or on the date of
transmittal by facsimile transmission (receipt confirmed) to the party to whom
notice is to be given, or on the fifth day after mailing by first class mail,
postage prepaid, return receipt requested, to the party whom notice is to be
given, in each case addressed to each holder of record at his address appearing
on the books of the Corporation.

                  (g) OTHER RIGHTS. Except as expressly set forth otherwise
herein, the holders of Series B Preferred shall have the same rights as the
holders of the Common Stock, determined, where applicable, as if all of such
holders' shares of Series B Preferred had been converted, as provided in Section
3, into Common Stock at the Series B Conversion Rate then in effect.

                         C. UNDESIGNATED PREFERRED STOCK

                  The Board of Directors or any authorized committee thereof is
expressly authorized, to the fullest extent permitted by law, to provide for the
issuance of the shares of Undesignated Preferred Stock in one or more series of
such stock, and by filing a certificate pursuant to applicable law of the State
of Delaware, to establish or change from time to time the number of shares of
each such series, and to fix the designations, powers, including voting


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powers, full or limited, or no voting powers, preferences and the relative,
participating, optional or other special rights of the shares of each series and
any qualifications, limitations and restrictions thereof.

                                    ARTICLE V

                               STOCKHOLDER ACTION

         1. ACTION WITHOUT MEETING. Except as otherwise provided herein, any
action required or permitted to be taken by the stockholders of the Corporation
at any annual or special meeting of stockholders of the Corporation must be
effected at a duly called annual or special meeting of stockholders and may not
be taken or effected by a written consent of stockholders in lieu thereof.

         2. SPECIAL MEETINGS. Except as otherwise required by statute and
subject to the rights, if any, of the holders of any series or class of
Preferred Stock, special meetings of the stockholders of the Corporation may be
called only by the Board acting pursuant to a resolution approved by the
affirmative vote of a majority of the Directors then in office. Only those
matters set forth in the notice of the special meeting may be considered or
acted upon at a special meeting of stockholders of the Corporation.

                                   ARTICLE VI

                                    DIRECTORS

         1. GENERAL. The business and affairs of the Corporation shall be
managed by or under the direction of the Board except as otherwise provided
herein or required by law.

         2. ELECTION OF DIRECTORS. Election of Directors need not be by written
ballot unless the By-laws of the Corporation (the "By-laws") shall so provide.

         3. NUMBER OF DIRECTORS; TERM OF OFFICE. The number of Directors of the
Corporation shall be fixed solely and exclusively by resolution duly adopted
from time to time by the Board. The Directors, other than those who may be
elected by the holders of any class or series of Preferred Stock, shall be
classified, with respect to the term for which they severally hold office, into
three classes, as nearly equal in number as reasonably possible. The initial
Class I Directors of the Corporation shall be Mark Lampert and Daniel Van Riper;
the initial Class II Directors of the Corporation shall be Zola Horovitz and
Bernard Beer; and the initial Class III Directors of the Corporation shall be
Arnold Lippa and Patrick Ashe. The initial Class I Directors shall serve for a
term expiring at the annual meeting of stockholders to be held in 2003, the
initial Class II Directors shall serve for a term expiring at the annual meeting
of stockholders to be held in 2004, and the initial Class III Directors shall
serve for a term expiring at the annual meeting of stockholders to be held in
2005. At each annual meeting of stockholders, Directors


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elected to succeed those Directors whose terms expire shall be elected for a
term of office to expire at the third succeeding annual meeting of stockholders
after their election. Notwithstanding the foregoing, the Directors elected to
each class shall hold office until their successors are duly elected and
qualified or until their earlier resignation or removal.

         Notwithstanding the foregoing, whenever, pursuant to the provisions of
Article IV of this Certificate, the holders of any one or more classes or series
of Preferred Stock shall have the right, voting separately as a series or
together with holders of other such series, to elect Directors at an annual or
special meeting of stockholders, the election, term of office, filling of
vacancies and other features of such directorships shall be governed by the
terms of this Certificate and any certificate of designations applicable
thereto.

         4. VACANCIES. Subject to the rights, if any, of the holders of any
class or series of Preferred Stock to elect Directors and to fill vacancies in
the Board relating thereto, any and all vacancies in the Board, however
occurring, including, without limitation, by reason of an increase in size of
the Board, or the death, resignation, disqualification or removal of a Director,
shall be filled solely and exclusively by the affirmative vote of a majority of
the remaining Directors then in office, even if less than a quorum of the Board,
and not by the stockholders. Any Director appointed in accordance with the
preceding sentence shall hold office for the remainder of the full term of the
class of Directors in which the new directorship was created or the vacancy
occurred and until such Director's successor shall have been duly elected and
qualified or until his or her earlier resignation or removal. Subject to the
rights, if any, of the holders of any class or series of Preferred Stock to
elect Directors, when the number of Directors is increased or decreased, the
Board shall, subject to Article VI.3 hereof, determine the class or classes to
which the increased or decreased number of Directors shall be apportioned;
PROVIDED, HOWEVER, that no decrease in the number of Directors shall shorten the
term of any incumbent Director. In the event of a vacancy in the Board, the
remaining Directors, except as otherwise provided by law, shall exercise the
powers of the full Board until the vacancy is filled.

         5. REMOVAL. Subject to the rights, if any, of any class or series of
Preferred Stock to elect Directors and to remove any Director whom the holders
of any such stock have the right to elect, any Director (including persons
elected by Directors to fill vacancies in the Board) may be removed from office
(i) only with cause and (ii) only by the affirmative vote of the holders of 75%
or more of the shares then entitled to vote at an election of Directors. At
least forty-five (45) days prior to any meeting of stockholders at which it is
proposed that any Director be removed from office, written notice of such
proposed removal and the alleged grounds thereof shall be sent to the Director
whose removal will be considered at the meeting.


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                                  ARTICLE VII

                             LIMITATION OF LIABILITY

         A Director of the Corporation shall not be personally liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a Director, except for liability (a) for any breach of the Director's
duty of loyalty to the Corporation or its stockholders, (b) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (c) under Section 174 of the DGCL or (d) for any transaction
from which the Director derived an improper personal benefit. If the DGCL is
amended after the effective date of this Certificate to authorize corporate
action further eliminating or limiting the personal liability of Directors, then
the liability of a Director of the Corporation shall be eliminated or limited to
the fullest extent permitted by the DGCL, as so amended.

         Any repeal or modification of this Article VII by either of (i) the
stockholders of the Corporation or (ii) an amendment to the DGCL, shall not
adversely affect any right or protection existing at the time of such repeal or
modification with respect to any acts or omissions occurring before such repeal
or modification of a person serving as a Director at the time of such repeal or
modification.

                                  ARTICLE VIII

                              AMENDMENT OF BY-LAWS

         1. AMENDMENT BY DIRECTORS. Except as otherwise provided by law, the
By-laws of the Corporation may be amended or repealed by the Board by the
affirmative vote of a majority of the Directors then in office.

         2. AMENDMENT BY STOCKHOLDERS. The By-laws of the Corporation may be
amended or repealed at any annual meeting of stockholders, or special meeting of
stockholders called for such purpose as provided in the By-laws, by the
affirmative vote of at least 75% of the outstanding shares entitled to vote on
such amendment or repeal, voting together as a single class; PROVIDED, HOWEVER,
that if the Board recommends that stockholders approve such amendment or repeal
at such meeting of stockholders, such amendment or repeal shall only require the
affirmative vote of the majority of the outstanding shares entitled to vote on
such amendment or repeal, voting together as a single class.

                                   ARTICLE IX

                    AMENDMENT OF CERTIFICATE OF INCORPORATION

         The Corporation reserves the right to amend or repeal this Certificate
in the manner now or hereafter prescribed by statute and this Certificate, and
all rights conferred upon stockholders herein are granted subject to this
reservation. Whenever any vote of the holders of voting stock is required to
amend or repeal any provision of this Certificate, and in addition to any other
vote of holders of voting stock that is required by this Certificate or by law,
such amendment or repeal shall require the affirmative vote of the majority of
the outstanding shares entitled to vote on such amendment or repeal, and the
affirmative vote of the majority of the outstanding shares of each class
entitled to vote thereon as a class, at a duly constituted meeting of
stockholders called expressly for such purpose; PROVIDED, HOWEVER, that the
affirmative vote of not less than 75% of


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the outstanding shares entitled to vote on such amendment or repeal, and the
affirmative vote of not less than 75% of the outstanding shares of each class
entitled to vote thereon as a class, shall be required to amend or repeal any
provision of Article V, Article VI, Article VII, Article VIII or Article IX of
this Certificate.

                                  [End of Text]



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         THIS FOURTH AMENDED AND RESTATED CERTIFICATE OF INCORPORATION is
executed as of this 29th day of April, 2002.


                                             DOV PHARMACEUTICAL, INC


                                             By: /s/ Arnold Lippa
                                                --------------------------------
                                                 Name: Arnold Lippa
                                                      --------------------------
                                                 Title: Chief Executive Officer
                                                       -------------------------