Exhibit 10.36

AMENDMENT OF DOV PHARMACEUTICAL, INC., 
CONVERTIBLE EXCHANGEABLE PROMISSORY NOTE

Amendment Agreement dated March    , 2003, among Elan Corporation plc ("Elan"), Elan International Services, Ltd. ("EIS"), Elan Pharma
International Limited ("EPIL"), DOV Pharmaceutical, Inc. ("DOV" or "Maker"), DOV Newco, Ltd. ("DOV Newco"), and Nascime Limited ("Nascime")

Whereas
Maker issued to EIS its convertible exchangeable promissory note dated January 21, 1999, in the principal amount of $8,010,000 (the "Note") in connection with a joint
venture transaction encompassing a securities purchase agreement between EIS and DOV ("SPA") and a joint development and operating agreement ("JDOA") among Elan, EIS, DOV, DOV Newco and Nascime, each
dated as of January 19, 1999;

Whereas
EIS subsequently transferred the Note to EPIL;

Whereas
pursuant to section 9(c) of the Note, Maker, EIS and EPIL wish to amend the Note and all parties wish to eliminate in the SPA and JDOA all references to the Newco Exchange
Right as defined in section 4 of the Note;

Now
therefore for good and sufficient consideration the parties agree as follows:











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Each
party represents severally to each of the others as follows:



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If to Elan:

Elan Corporation, plc
Lincoln House, Lincoln Place
Dublin 2, Ireland
Attn: Vice President, General CounselIf to EIS:

Elan International Services, Ltd.
102 St. James Court
Flatts, Smiths Parish
Bermuda SL04
Attn: DirectorIf to EPIL:

Elan Pharma International Limited
Wil House Shannon Business Park
Shannon, Co. Clare Ireland
Attn: PresidentIf to DOV:

DOV Pharmaceutical, Inc.
433 Hackensack Avenue
Hackensack, New Jersey 07601
Attn: CEO
With copy to: General Counsel


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In witness whereof the parties have caused this Amendment Agreement to be executed by their duly authorized representatives intended to be legally bound.

| |  | Elan Corporation, plc            
| |  | ---------------------------------
| |  | By:                              
| |  | Elan International Services, Ltd.
| |  | By:                              
| |  | Elan Pharma International Limited
| |  | By:                              
| |  | DOV Pharmaceutical, Inc.         
| |  | By:                              
| |  | DOV Newco, Ltd.                  
| |  | By:                              
| |  | Nascime Limited                  
| |  | By:                              

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Exhibit A

WARRANT AGREEMENT

Warrant Agreement effective as of the date set forth on the signature page hereof between DOV Pharmaceutical, Inc., a Delaware corporation (the "Company"),
and Elan International Services, Ltd. ("Holder")

Whereas
the Company has agreed to issue Holder warrants to purchase shares of the Company's common stock, par value $.0001 ("Common Stock"), for $10.00 per share;

Wheras
Holder has represented to the Company that referring to the Rights Plan (as defined in Exhibit B) there has been no change in Beneficial ownership by Elan and its
affiitates and associates since the Record Date (all terms as defined in the Rights Plan) other than pursuant to this Warrant Agreement.

Now,
therefore, the parties agree as follows:



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If to the Company:DOV Pharmaceutical, Inc.
433 Hackensack Avenue
Hackensack, New Jersey 07601
Attn: Robert Horton, General CounselIf to Holder:Elan International Services, Ltd.
102 St. James Court
Flatts, Smiths Parish
Bermuda SL04
Attn: Director


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[Signature Page to Follow]

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In
witness whereof, the parties hereto have caused this agreement to be duly executed, as of the date below.

Dated:
March    , 2003

| |  | DOV Pharmaceutical, Inc.         
| |  | ---------------------------------
| |  | By:                              
| |  | Elan International Services, Ltd.
| |  | By:                              

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Exhibit A (to Warrant Agreement)

FORM OF WARRANT CERTIFICATE

THE
WARRANTS REPRESENTED BY THIS CERTIFICATE AND THE SHARES OF STOCK ISSUABLE UPON EXERCISE HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), FOR
PUBLIC RESALE AND MAY NOT BE OFFERED, TRANSFERRED OR SOLD EXCEPT PURSUANT TO (i) AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES OR BLUE SKY
LAWS, (ii) RULE 144 UNDER THE SECURITIES ACT (OR ANY SIMILAR RULE UNDER THE SECURITIES ACT RELATING TO THE DISPOSITION OF SECURITIES) TO THE EXTENT APPLICABLE TOGETHER WITH AN OPINION OF
COUNSEL REASONABLY SATISFACTORY TO ISSUER THAT SUCH TRANSFER IS PERMITTED OR (iii) AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO ISSUER THAT AN EXEMPTION FROM REGISTRATION UNDER THE
SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES OR BLUE SKY LAWS IS AVAILABLE.

THE
EXERCISE, TRANSFER AND EXCHANGE OF THE WARRANTS REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO THE WARRANT AGREEMENT BETWEEN DOV PHARMACEUTICAL, INC. AND HOLDER DATED AS OF MARCH
    , 2003.

This
Warrant Certificate certifies that Elan International Services Ltd. ("Holder"), is the registered holder of Warrants to purchase, at any time from the date of the warrant
agreement dated as of March    , 2003, between DOV Pharmaceutical, Inc. and Holder ("the Warrant Agreement"), until 5:30 p.m. Eastern Standard Time on January 21, 2006
("Expiration Date"), up to 75,000 fully-paid and non-assessable shares of common stock, par value $.0001 per share ("Common Stock"), of DOV Pharmaceutical, Inc. (the
"Company"), at an exercise price of $10.00 per share ("Exercise Price"), upon surrender of this Warrant Certificate, together with the attached Form of Election to Purchase, and
payment of the Exercise Price to the Company. Holder may elect to exercise this Warrant Certificate and receive a lesser number of shares of Common Stock on a cashless net issuance basis.

After
the Expiration Date all Warrants evidenced hereby, unless exercised prior thereto, shall be void.

The
Warrant Agreement is hereby incorporated by reference and made a part of this Warrant Certificate and is hereby referred to for a description of the rights, obligations, duties and
restrictions of the Company and holder of the Warrants.

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In
witness whereof, the Company has caused this Warrant Certificate to be duly executed as of the date of the Warrant Agreement.

| |  | DOV PHARMACEUTICAL, INC.
| |  | ------------------------
| |  | By:                     

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Exhibit B (to Warrant Agreement)

Form of Election to Purchase

The undersigned irrevocably elects to exercise the right represented by the attached Warrant Certificate to purchase 75,000 shares of Common Stock, par value
$.0001, of DOV Pharmaceutical, Inc.(a) at an exercise price of $10.00 per share and tenders in payment for such common stock a wire transfer payable in New York Clearing House Funds to the
order of DOV Pharmaceutical, Inc., in the amount of $750,000 or (b) at the election of the undersigned indicated below, instructs the company to deliver in lieu of such 75,000 shares,
such number thereof calculated on a cashless net issuance basis.

|By: |  | Name:
Title:                             |  |     |  |  |  |  |  | 
|--- |  | ---------------------------------------- |  | --- |  |  |  |  |  | 
|    |  | Election:    Cashless net issuance basis |  | Yes |  |  |  | 
|    |  |                                          |  |     |  |  |  |  |  | 

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Exhibit B

WHEREAS,
DOV Pharmaceutical, Inc. (the "Corporation") is a party to that certain the Shareholder Rights Agreement dated as of October 8, 2002 (the "Rights Plan") between
the Corporation and Continental Stock & Transfer Trust Co., as Rights Agent (capitalized terms used but not otherwise defined herein have the meanings set forth in the Rights Plan);

WHEREAS,
in connection with the transactions contemplated by the Amendment of DOV Pharmaceutical, Inc. Convertible Exchangeable Promissory Note dated March    , 2003
(the "Note Amendment"), the Board of Directors of the Corporation (the "Board") deems it necessary and desirable and in the best interests of the Corporation to confirm the Board's and the
Corporation's interpretation of, and intent with respect to, the matters referenced below relating to the Rights Plan.

NOW,
THEREFORE, BE IT:

RESOLVED,
that, assuming no other changes in the Beneficial Ownership by Elan Corporation, plc and its Affiliates and Associates (collectively, "Elan") occurring since the Grandfathered
Time other than the transactions contemplated by the Note Amendment, the Beneficial Ownership by Elan, including the conversion into or exercise for Common Stock, of any of the following securities
shall not be deemed by the Board or the Corporation to cause Elan to become an Acquiring Person under the Rights Plan:

RESOLVED,
that, without limiting the generality of the foregoing, none of the following shall be deemed by the Board or the Corporation to cause Elan to become an Acquiring Person under
the Rights Plan: (i) the outstanding principal amount of the Convertible Note as of the date hereof, together with any increases in the outstanding principal amount of the Convertible Note as a
result of disbursements of funds there under; (ii) accrual of interest on, or its capitalization and addition to the outstanding principal of, the Convertible Exchangeable Note or the
Convertible Note; or (iii) adjustments to the conversion or exercise price of the Series B Preferred Stock, the Warrants, the Convertible Exchangeable Note or the Convertible Note
pursuant to the terms of the applicable governing documents as such terms exist as of the date hereof; and be it further

RESOLVED,
that, assuming no other changes in the Beneficial Ownership by Elan occurring since the Grandfathered Time other than the transactions contemplated by the Note Amendment, the
Board and the Corporation hereby confirm that the 75,000 Warrants, dated March 2003, of the Corporation issued to Elan fall within Elan's Grandfathered Percentage under the Rights Plan; and be
it further

RESOLVED,
that the officers of the Corporation be, and each of them hereby is, authorized and directed, for and on behalf of the Board and the Corporation, to prepare, execute and
deliver any such documents or instruments, and to take all such other actions, deemed necessary or appropriate or reasonably requested by Elan to confirm any of the foregoing matters to third parties.

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