SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                 ---------------



                                    FORM 8-K

                                 CURRENT REPORT




     Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

       Date of Report (Date of earliest event reported): January 17, 2006

                       LIGAND PHARMACEUTICALS INCORPORATED
             (Exact name of registrant as specified in its charter)

                                    DELAWARE
                 (State or other jurisdiction of incorporation)

                                    000-20720
                            (Commission File Number)

                           10275 SCIENCE CENTER DRIVE
                              SAN DIEGO, CALIFORNIA
                    (Address of principal executive offices)

                                 (858) 550-7500
              Registrant's telephone number, including area code)

                                   77-0160744
                      (I.R.S. Employer Identification No.)

                                   92121-1117
                                   (Zip Code)









ITEM 1.01. ENTRY INTO A MATERIAL DEFINITIVE AGREEMENT.

         On January 17, 2006 the Company  entered into a Termination  and Return
of Rights  Agreement  with Organon  USA,  Inc.  that  terminates  the  AVINZA(R)
co-promotion  agreement  between the two companies and returns  AVINZA rights to
Ligand.

         The  effective  date of the  termination  agreement is January 1, 2006,
however the parties  have agreed to continue to  cooperate  during a  transition
period ending September 30, 2006 to promote the product.  That transition period
co-operation  includes  a minimum  number of  product  sales  calls per  quarter
(100,000  for  Organon and 30,000 for Ligand  with an  aggregate  of 375,000 and
90,000  respectively  for the  transition  period) as well as the  transition of
ongoing  promotions,  managed care  contracts,  clinical  trials and key opinion
leader  relationships  to Ligand.  During the transition  period Ligand will pay
Organon an amount equal to 23 percent of AVINZA net sales as reported by Ligand.
Ligand  will also pay and be  responsible  for the design and  execution  of all
clinical, advertising and promotion expenses and activities.

         The  agreement  includes  a  release  of  claims  arising  prior to the
effective date,  including  claims  regarding prior  co-promote fees, and Ligand
will pay Organon  $14.75  million by January 30,  2006 as a  settlement  payment
relevant to those fees and claims. In consideration of the early termination and
return of rights under the terms of the agreement,  Ligand will  unconditionally
pay Organon $37.75  million on or before  October 15, 2006.  Ligand will further
pay Organon $10.0 million on or before  January 15, 2007,  provided that Organon
has made its minimum  required level of sales calls.  Under certain  conditions,
including  change of control,  the cash payments will  accelerate.  In addition,
after the  transition  period,  Ligand will make quarterly  royalty  payments to
Organon  equal to 6.5 percent of AVINZA net sales up to and  including  December
31,  2012 and  thereafter  six  percent  through  patent  expiration,  currently
anticipated to be November of 2017.

         The  company  intends  to file the  Termination  and  Return  of Rights
Agreement  with its annual  report on form 10-K for the year ended  December 31,
2005 and to request confidential treatment of certain portions.

ITEM 9.01 FINANCIAL STATEMENTS AND EXHIBITS

(d)      Exhibits

EXHIBIT NUMBER        DESCRIPTION
-----------------     --------------------

99.1                  Press release of the Company dated January 17, 2006


                                   SIGNATURES

         Pursuant to the  requirements  of the Securities  Exchange Act of 1934,
the  registrant  has  caused  this  report  to be  signed  on its  behalf by the
undersigned.


                              LIGAND PHARMACEUTICALS INCORPORATED




    Date: January 20, 2006    By:      /s/ Warner R. Broaddus
                              Name:    Warner R. Broaddus
                              Title:   Vice President, General Counsel & 
                                       Secretary