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Exhibit 10.152

                           [ABBOTT LETTERHEAD]

                             March 14, 1996

Mr. William L. Respess
*
CONFIDENTIAL  *
Senior V.P., General Counsel
TREATMENT REQUESTED
Ligand Pharmaceuticals Inc.
9393 Towne Center Drive
San Diego, CA 92121

Dear Mr. Respess:

Abbott Laboratories hereby confirms the extension of our
Research, Development
and License Agreement dated July 6, 1994, for a third year
(July 6, 1996
through July 5, 1997), with an amendment to Section 3.1
and Exhibit A, to set
the Ligand staffing for this third year to
*________*________* Ligand full-time
equivalents and an Aggregate Annual Research Fee for
Contract Year 3,
therefore, as *__________________*__________________*.
This revision reflects
the discussions of our respective representatives to the
Joint Research Policy
Committee over the past months. This modification is
intended to provide the
optimum distribution of resources for achieving Research
Program success.

For the convenience of future renewal discussions, Abbott
also proposes to
amend Section 14.3.1 to provide for "notice to be given
not later than four (4)
months...", with all other provisions remaining as
originally provided.

If you agree with the amendments outlined above, please
sign
both copies of
this letter amendment and return one copy to me.

Thanks very much for your assistance.

Sincerely,


Alan S. Rosenthal, M.D.                       ACCEPTED AND
AGREED:
Vice President, Discovery R&D                 LIGAND
PHARMACEUTICALS INC.


                                              By: WILLIAM
L. RESPESS

____________________________
                                                  William
L. Respess
                                                  Senior
Vice President,
                                                  General
Counsel and Secretary
                                                  Date  3-
2996




Certain confidential portions of this Exhibit were omitted
by means of blackout of the text (the "Mark").
This Exhibit has been filed separately with the Secretary
of the Commission without the Mark pursuant to
the Company's Application Requesting Confidential Treatment
under Rule 406 under the Securities Act.