Exhibit 10.8h

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May 15, 2000

NPS Pharmaceuticals, Inc.
420 Chipeta Way
Salt Lake City, Utah 84108

RE: Amendment Agreement

Dear Sirs:

     This Amendment Agreement (hereinafter “Amendment Agreement”) will confirm
that the November 1, 1993 Collaborative Research and License Agreement between
NPS Pharmaceuticals, Inc., a corporation of the state of Delaware, having a
place of business at 420 Chipeta Way, Salt Lake City, Utah 84108, U.S.A. (herein
referred to as “NPS”) and SmithKline Beecham Corporation, a corporation of the
Commonwealth of Pennsylvania, having a place of business at One Franklin Plaza,
Philadelphia, Pennsylvania 19101, U.S.A. (hereinafter referred to as “SB”) as
amended (hereinafter collectively referred to as “Original Agreement”) shall be
further amended as follows:

• Paragraph 1.20 shall be replaced in its entirety with the following:      
“1.20     “IND” shall mean an Investigational New Drug Application for COMPOUND
in the FIELD filed by or on behalf of SB with the FDA or equivalent
application(s) filed with the appropriate regulatory authorities in the United
Kingdom, France, Germany, Italy, Spain or Japan, provided that the purpose of
such IND is not to conduct experimental medicine based on a toxicology package
insufficient to support multiple dose studies.     • Paragraph 5.01 shall be
amended as indicated, additions are indicated in bold text, deletions are
indicated by stike through and bold text:    

  EFFECTIVE DATE U.S. $ 4,000,000                     January 1, 1995 U.S. $
2,000,000                     First Program Status U.S. $ 3,000,000            
        First Experimental Medicine IND U.S. $ 1,000,000                    
First IND U.S. $ 2,000,000   (3,000,000)                 NDA Filing for First
COMPOUND U.S. $ 5,000,000                     Second Program Status U.S. $
2,000,000                     First IND for Second COMPOUND U.S. $ 2,000,000    
                Third Program Status U.S. $ 1,000,000                     First
IND for Third COMPOUND U.S. $ 1,000,000      

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• Add the following as new Paragraph 5.01(1):        “(I) by the term "First
Experimental Medicine IND” as used in this Paragraph 5.01 is meant the first
Investigational New Drug Application for any COMPOUND in the FIELD filed by or
on behalf of SB with the FDA provided that the purpose of such IND is to conduct
experimental medicine human trials based on a toxicology package insufficient to
support multiple dose studies. Multiple dose studies shall not include single
doses separated by a wash-out period equivalent to at least 7 days or 5
half-lives of the COMPOUND.   • This Amendment Agreement shall be retroactively
effective as of November 1, 1993.     • All other terms and conditions of the
Original Agreement shall remain in full force and effect.

          Please indicate your acceptance of this Amendment Agreement by signing
and dating the duplicate copies of this letter below and returning one such
fully executed copy to SB.

  Very truly yours,
SMITHKLINE BEECHAM CORPORATION           By: /s/ Donald F. Parman     Donald F.
Parman   Title: Secretary   Date: May 15, 2000

AGREED TO AND ACCEPTED:
NPS PHARMACEUTICALS, INC.

By: /s/ James K. Jensen   James K. Jensen Title: Vice President     Date: May
15, 2000

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