EXHIBIT 10.32
                                                                   -------------

          CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT,
        MARKED BY BRACKETS AND ASTERISKS, IS FILED WITH THE SECRETARY OF
        THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 OF
                 THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED





                                    MAY, 1996





                       SYNAPTIC PHARMACEUTICAL CORPORATION

                                       and

                               CIBA-GEIGY Limited





                                SUPPLEMENT NO. 1
                       to the Research & License Agreement
               between the parties made as of the 4th August, 1994

























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                                                   SUPPLEMENT NO. 1

THIS  SUPPLEMENT  NO.  1 is  made  as of the  31st  day of  May,  1996  between:
CIBA-GEIGY  Limited,  a Swiss corporation having its principal place of business
at Klybeckstrasse 141, CH-4002 Basel,  Switzerland  (hereinafter  referred to as
"CIBA-GEIGY"),  and SYNAPTIC PHARMACEUTICAL  CORPORATION, a Delaware corporation
having its principal place of business at 215 College Road, Paramus,  New Jersey
07652-1410, USA (hereinafter referred to as "SYNAPTIC").


WHEREAS:

     (A) By a Research and  Development  Agreement  (hereinafter  referred to as
     "the PP Receptor  Agreement")  made  between  the parties  hereto as of the
     Fourth day of August,  1994,  CIBA-GEIGY and SYNAPTIC  agreed that during a
     period of 36 months they would collaborate in a research programme aimed at
     discovering and developing  compounds  which,  through the modulation of PP
     Receptors (as defined in the PP Receptor Agreement), are useful in treating
     obesity, eating disorders and/or one or more cardiovascular  diseases, such
     as congestive  heart failure and hypertension  (hereinafter  referred to as
     "the PP Receptor Programme").

(B)      The  parties  wish to extend the period of  collaboration  under the PP
         Receptor  Agreement  from 36 months to 48  months,  and to enter into a
         further  collaborative  research  programme  aimed at the discovery and
         development  of compounds  which,  through [***] are useful in treating
         obesity and eating and metabolic disorders  (hereinafter referred to as
         "the [***] Programme").

(C)      The parties have agreed to amend the PP Receptor Agreement and to enter
         into an  additional  Research and  Development  Agreement for the [***]
         Programme  (hereinafter  referred to as "the [***] Agreement") on terms
         hereinafter appearing.

NOW,  THEREFORE,  in  consideration  of the premises and of the mutual covenants
hereinafter set out, the parties hereby agree as follows:

1.       DEFINITIONS
         When  used in this  Agreement  capitalised  words  shall  have the same
         meanings as in the PP Receptor Agreement and in the [***] Agreement.


2.       AMENDMENT OF THE PP RECEPTOR AGREEMENT

         With  effect  from the  fourth  day of August,  1995,  the PP  Receptor
         Agreement shall be amended as follows:

2.1      Sections 1.2,  1.17,  2.0,  2.1, 2.7, 3.0, 3.2, 4.0, 4.1, 4.2,  4.3(a),
         4.3(b)(1) and 6.0(b)(i)  are hereby  amended by deleting  therefrom the
         reference  therein to "the term of this  Agreement" and by substituting
         therefor the words "the Project Term".


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2.2      Section  1.14 is hereby  amended by deleting  therefrom  the words "the
         term of this Agreement or within a three (3) year period  following the
         termination or expiry thereof" and by  substituting  therefor the words
         "the Project Term or the Post-Project Term".

2.3      Section  1.15 is  hereby  amended  by adding  immediately  prior to the
         period in the first sentence contained therein the following:

                  "and in the case of financial support provided with respect to
                  the twelve (12) month  period  beginning in August,  1995,  to
                  support both the Project and the [***] Project."

2.4      There are hereby added immediately following Section 1.20 the following
         new Sections:

         "1.21    "[***] Agreement" means the Research and Development Agreement
                  dated as of the 31st May,  1996,  and made effective as of the
                  Fourth day of August, 1995.

         1.22     "[***]  Project" means the  collaborative  research  programme
                  relating to [***] that is the subject of the [***] Agreement.

         1.23     "Project Term" means the period commencing as of the Effective
                  Date and ending on the Third day of August,  1998, or the date
                  of termination  of this Agreement  pursuant to Section 5.2, if
                  earlier.

         1.24     "Post-Project Term" means the period of thirty-six (36) months
                  immediately following the Project Term."

2.5      There is hereby added immediately following Section 2.7 the following
         new Section:

     "2.8 Joint Project Team and Steering Committee Meetings. It is contemplated
     that members of the Project Team and Steering Committee may also be members
     of the Project Team and Steering  Committee for the [***] Project.  In view
     of this  potential  overlap in membership,  as well as the potential  value
     perceived  by both  parties in having the two  Project  Teams and  Steering
     Committees  interact and share scientific data and  observations  regarding
     their respective  projects,  it is also  contemplated  that the two Project
     Teams and Steering Committees may hold joint meetings,  prepare single sets
     of minutes reflecting such meetings and prepare joint reports such as those
     required by Section 4.0."

2.6      The following text shall be substituted for the existing text of 
         Section 3.1:

                  "Amount.Project Funds for the twelve month period beginning as
                  of the Effective Date shall be [***] and Project Funds for the
                  twelve month period beginning as of the Fourth day of August,
                  1995 shall be [***]


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                  [***].  For each  period  of  twelve  (12)  months  thereafter
                  Project Funds shall be an amount equal to [***],  (as adjusted
                  for  inflation  pursuant  to the  Bureau  of Labor  Statistics
                  Consumer Price Index for Urban  Consumers,  New York, N.E. New
                  Jersey Metropolitan Region Price Index ("the CPI")) multiplied
                  by the number of SYNAPTIC  FTEs which the  Steering  Committee
                  has decided  should be  employed  on the  Project  during such
                  period.  This  figure  shall  be  subject  to  adjustment  for
                  inflation  pursuant to the CPI on each subsequent  anniversary
                  of the Effective Date."

2.7      The following sentence shall be substituted for the first two sentences
         of Section 3.3:

                  "SYNAPTIC shall at substantially  all times during the Project
                  Term  assign  such  number of FTEs to work on the  Project  as
                  shall be agreed from time to time by the Steering Committee."

2.8      Sections  4.3(b)(2)  and  6.0(a)(i)  are  hereby  amended  by  deleting
         therefrom the references therein to "the term of this Agreement and for
         thirty-six  (36)  calendar  months  after the  expiry  thereof"  and by
         substituting  therefor the words "the Project Term and the Post-Project
         Term."

2.9      The third  paragraph  of  Section  4.7 is hereby  amended  by  deleting
         therefrom the reference  therein to "the  Agreement"  and the reference
         therein  to  "the  Agreement  plus   thirty-six   (36)  months  and  by
         substituting therefor the words "the Post-Project Term".

2.10     The following text shall be substituted for the text of Section 5.0:

                  "Term.   This  Agreement  shall  remain  in  effect  from  the
                  Effective Date until the expiration of all royalty obligations
                  pursuant to Section 6, unless sooner  terminated in accordance
                  with the provisions of Section 5.2 or 5,3."

2.11     Section 5.1 is hereby  amended by  deleting  the  reference  therein to
         "this  Agreement"  and  substituting  therefor  the words "the  Project
         Term".

2.12     The following text shall be substituted for the text of Section 5.4:

                  "Effect of  Termination  or Expiry.  Termination  or expiry of
                  this Agreement  shall not affect the rights and obligations of
                  the parties  accrued under this Agreement prior to termination
                  or expiry,  all of which shall  survive  such  termination  or
                  expiry.  In addition  the  liabilities  of the parties for any
                  breach of this Agreement shall survive any such termination or
                  expiry.  Sections  1.0 through  1.24,  4.2 (the last  sentence
                  only) 4.4 (the second paragraph only),4.5, 4.6, 4.7, 4.8, 5.4,
                  6.1  through  6.6,  7, 8.3 and 8.5 shall  also,  except to the
                  extent expressly limited by their terms or by other provisions
                  of this  Agreement,  also  survive  any  such  termination  or
                  expiry. Any Project Funds paid by CIBA-GEIGY but not committed
                  by

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                  SYNAPTIC at termination  shall be refunded to CIBA-GEIGY,  and
                  CIBA-  GEIGY shall have no further  obligation  to pay Project
                  Funds.

                  Notwithstanding  anything to the  contrary  contained  in this
                  Agreement,  if this  Agreement is  terminated  by either party
                  pursuant to Section 5.2,  then, in addition to the  provisions
                  referred to in the preceding paragraph,  the provisions hereof
                  pursuant to which the non-terminating party grants any license
                  to the  terminating  party shall survive such  termination (to
                  the extent provided therein)."


2.13     Save as amended hereby the PP Receptor Agreement shall continue in full
         force and effect.


3.       [***] AGREEMENT

         Contemporaneously with the execution of this Supplement No. 1, the
         parties will enter into the [***] Agreement.


4.       FUNDING OF PP RECEPTOR AND [***] PROGRAMMES

         Section 3.3 of the PP Receptor Agreement  originally  required SYNAPTIC
         at substantially  all times during the term of that Agreement to assign
         [***]  FTEs  to  work  on  the  PP  Receptor  Programme.   The  parties
         acknowledge that as from the Fourth August,  1995, due to progress made
         in such Programme,  the resources required to be devoted by SYNAPTIC to
         the PP Receptor  Programme have  diminished  and have therefore  agreed
         that it is  desirable  (i) to allocate  fewer than [***] FTEs to the PP
         Receptor  Programme  and (ii) to  allocate  those of the [***]  FTEs no
         longer required for that Programme to the [***] Programme. Accordingly,
         the parties agree that, from and after the Fourth day of August,  1995,
         SYNAPTIC  shall assign  [***] FTEs in aggregate to the two  Programmes,
         and CIBA shall fund the cost of [***]  SYNAPTIC  FTEs in the  aggregate
         for the two  Programmes.  While  the  level of  training  and  research
         experience of these FTEs may vary from time to time,  SYNAPTIC will use
         its  reasonable  best  efforts  to  ensure  that at least  [***] of the
         aggregate  number of FTE's  assigned  to the two  Programmes  will have
         educational degrees of Ph.D. or M.D., or research experience of greater
         than ten (10) years in a relevant  scientific field that qualifies them
         as equivalent to a Ph.D. or M.D. level researcher.


5.       ENTIRE AGREEMENT

         This  Supplement  No. 1, together with the PP Receptor  Agreement,  the
         Series  4  Stock  Purchase  Agreement  referred  to in the PP  Receptor
         Agreement and the [***] Agreement,  represents the entire agreement and
         understanding  between  the  parties  relating  to the  subject  matter
         hereof,  and  supersedes  all written or oral  agreements,  consents or
         understandings  (if any) with respect thereto given or made between the
         parties prior to the date hereof.

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AS WITNESS the signatures of the  representatives  of the parties hereto the day
and year first above written.

SYNAPTIC PHARMACEUTICAL CORPORATION

By:       /s/Kathleen P. Mullinix
          -----------------------
Name:     Kathleen P.  Mullinix
Title:    President


CIBA-GEIGY Limited

By:      /s/Dr. D.W. Scholer                                  /s/R.E. Walker
         -------------------              -----------------
Names:   Dr. D.W. Scholer                 R.E. Walker
Titles:  R & D Alliances                  Division Counsel




































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