EXHIBIT 10.244


                     SECOND ADDENDUM TO AMENDED AND RESTATED
                          REGISTRATION RIGHTS AGREEMENT


     This Second Addendum ("Addendum") to the Amended and Restated Registration
Rights Agreement dated June 29, 2000 ("Registration Rights Agreement") by and
among Ligand Pharmaceuticals Incorporated, a Delaware corporation (the
"Company"), and those entities (the "Investors") set forth on SCHEDULE A to the
Registration Rights Agreement is effective as of March 28, 2002.

                                    RECITALS

     A. On the date hereof, the Company has issued 102,151 shares of the
Company's Common Stock (the "Incentive Shares") to EIS pursuant to the terms of
that certain Incentive Agreement dated as of the date hereof among the Company,
EIS and Monksland Holdings B.V., a Dutch corporation.

     C. This Addendum serves to include the Incentive Shares within the
definition of "Registrable Securities" under the Registration Rights Agreement
pursuant to Section 2.6 of the Registration Rights Agreement.

     NOW, THEREFORE, in consideration of the mutual promises and covenants set
forth in the Registration Rights Agreement, the parties agree as follows:

     1. Section 1.1, paragraph (f) of the Registration Rights Agreement is
hereby restated in its entirety as follows:

          "(f) The term "Registrable Securities" means (i) the shares of Common
     Stock (or the shares of such other class of stock into which the Common
     Stock is converted) issuable upon conversion of those certain Unsecured
     Convertible Promissory Notes dated October 30, 1997 issued to S.R. One
     Limited (the "S.R. One Notes") pursuant to the Stock and Note Purchase
     Agreement dated February 3, 1995 (and upon such conversion of the S.R. One
     Notes, SCHEDULE A shall be updated to include such shares), (ii) the shares
     of Common Stock (or the shares of such other class of stock into which the
     Common Stock is converted) issuable upon conversion of that certain Warrant
     (the "Warrant") issued to SmithKline Beecham plc pursuant to the Stock
     Purchase Agreement dated April 24, 1998 (and upon such conversion of the
     Warrant, SCHEDULE A shall be updated to include such shares), (iii) the
     1,278,970 shares of Common Stock (or that number of shares of such other
     class of stock into which the Common Stock is converted) issued to EIS
     pursuant to the Stock Purchase Agreement dated September 30, 1998, (iv) the
     437,768 shares of Common Stock (or that number of shares of such other
     class of stock into which the Common Stock is converted) issued to EIS
     pursuant to the Securities Purchase Agreement, dated November 6, 1998 (as
     amended, the "Elan Securities Purchase Agreement"), (v) the shares of
     Common Stock (or the shares of such other class of stock into which the
     Common Stock is converted) issued or issuable upon conversion of the Zero
     Coupon Convertible Senior Notes due 2008 (the "Elan Notes") issued pursuant
     to the Elan Securities




     Purchase Agreement (and upon such conversion of the Elan Notes,
     SCHEDULE A shall be updated to include such shares), (vi) the 429,185
     shares of Common Stock (or that number of shares of such other class of
     stock into which the Common Stock is converted) issued to Elan pursuant to
     the Development, Licence and Supply Agreement dated November 9, 1998 (as
     amended, the "Elan License Agreement"), (vii) the shares of Common Stock
     (or the shares of such other class of stock into which the Common Stock is
     converted) that may be issued pursuant to the Elan License Agreement (and
     upon each such issuance, SCHEDULE A shall be updated to include such
     shares), (viii) the 52,742 shares of Common Stock (or that number of shares
     of such other class of stock into which the Common Stock is converted)
     issued to EIS pursuant to the Stock Purchase Agreement dated September 30,
     1999, (ix) the 91,406 shares of Common Stock (or that number of shares of
     such other class of stock into which the Common Stock is converted) issued
     to EIS upon the exercise of that certain Amended and Restated Series X
     Warrant for the Purchase of 91,406 Shares of Common Stock dated November
     22, 1999, (x) the 188,572 shares of Common Stock (or that number of shares
     of such other class of stock into which the Common Stock is converted)
     issued to EIS pursuant to the Incentive Agreement dated December 31, 1999,
     (xi) the 98,580 shares of Common Stock (or that number of shares of such
     other class of stock into which the Common Stock is converted) issued to
     EIS pursuant to the Incentive Agreement dated March 1, 2000, (xii) the
     274,843 shares of Common Stock (or that number of shares of such other
     class of stock into which the Common Stock is converted) issued to EIS
     pursuant to the Incentive Agreement dated December 20, 2001, (xiii) the
     102,151 shares of Common Stock (or that number of shares of such other
     class of stock into which the Common Stock is converted) issued to EIS
     pursuant to the Incentive Agreement dated March 28, 2002, and (xiv) any
     Common Stock issued as (or issuable upon the conversion or exercise of any
     warrant, right or other security which is issued as) a dividend or other
     distribution with respect to, or in exchange for or in replacement of the
     shares referenced in subsections (i) through (xiv) above, excluding in all
     cases, however, any Registrable Securities sold by a person in a
     transaction in which rights under this Agreement are not assigned.

     2. SCHEDULE A of the Registration Rights Agreement is hereby restated in
its entirety as attached to this Addendum.

     3. This Addendum may be executed in one or more counterparts.

     4. This Addendum shall be binding upon the Company, EIS, each holder of
Registrable Securities and each future holder of Registrable Securities pursuant
to Section 2.6 of the Registration Rights Agreement.

                [REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]



                                       2


     IN WITNESS WHEREOF, the parties have executed this Addendum as of the date
first above written.



LIGAND PHARMACEUTICALS INCORPORATED


By:      /S/WARNER BROADDUS

Its:     VP & GENERAL COUNSEL




ELAN INTERNATIONAL SERVICES, LTD.


By:      /S/KEVIN INSLEY

Its:     PRESIDENT


ELAN CORPORATION, PLC


By:      /S/WILLIAM DANIEL

Its:     COMPANY SECRETARY










                       [SIGNATURE PAGE TO SECOND ADDENDUM
             TO AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT]



                                       3


                                   SCHEDULE A

                                       to
                               Second Addendum to
               Amended and Restated Registration Rights Agreement



- ------------------------------------------------------ ---------------
                                                           SHARES
NAME                                                       ISSUED
- ------------------------------------------------------ ---------------
                                                          
Elan Corporation, plc                                       429,185

Elan International Services, Ltd.                        13,612,141

         TOTAL:                                          14,041,326
- ------------------------------------------------------ ---------------