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                                                                     EXHIBIT 3.3


                            CERTIFICATE OF AMENDMENT

                                     OF THE

                          CERTIFICATE OF INCORPORATION

                                       OF

                          HUMAN GENOME SCIENCES, INC.



     Pursuant to Section 242 of the General Corporation Law, Human Genome 
Sciences, Inc. (the "Corporation"), a corporation organized and existing under
and by virtue of the General Corporation Law of the State of Delaware, DOES 
HEREBY CERTIFY THAT:

          1.   The name of the corporation is Human Genome Sciences, Inc.

          2.   The Certificate of Incorporation of the Corporation, as amended,
is hereby amended by adding the following as the second and third paragraphs of 
Article V:  
               
               "Terms of Directors. The number of Directors of the Corporation
               shall be fixed by resolution duly adopted from time to time by
               the Board of Directors.  The Directors, shall be classified,
               with respect to the term for which they hold office, into three
               classes, as nearly equal in number as possible.  The initial 
               Class I Directors shall serve for a term expiring at the annual 
               meeting of stockholders to be held in 2000, the initial Class II
               Directors shall serve for a term expiring at the annual meeting 
               of stockholders to be held in 1999, and the initial Class III 
               Directors shall serve for a term expiring at the annual meeting 
               of stockholders to be held in 1998.  At each annual meeting of 
               stockholders, the successor or successors of the


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               class of Directors whose term expires at that meeting shall be 
               elected by a plurality of the votes cast at such meeting and 
               shall hold office for a term expiring at the annual meeting of 
               stockholders held in the third year following the year of their
               election.  The Directors elected to each class shall hold office
               until their successors are duly elected and qualified or until
               their earlier resignation or removal.

               "Vacancies.  Any and all vacancies in the Board of Directors, 
               however occurring, including, without limitation, by reason of 
               an increase in size of the Board of Directors, or the death, 
               resignation, disqualification or removal of a Director, shall be 
               filled solely by the affirmative vote of a majority of the 
               remaining Directors then in office, even if less than a quorum
               of the Board of Directors.  Any Director appointed in accordance
               with the preceding sentence shall hold office until the annual 
               meeting of stockholders at which the class of Directors for
               which he or she has been chosen is elected and until such
               Director's successor shall have been duly elected and qualified
               or until his or her earlier resignation or removal. When the
               number of Directors is increased or decreased, the Board of
               Directors shall determine the class or classes to which the
               increased or decreased number  of Directors shall be apportioned
               so as to maintain each class as nearly equal in number


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               as possible; provided, however, that no decrease in the number 
               of Directors shall shorten the term of any incumbent Director.

          3.   At a meeting of the Board of Directors of the Corporation, 
resolutions were duly adopted setting forth the foregoing amendment to the 
Certificate of Incorporation, declaring said amendment to be advisable and 
seeking the written consent of stockholders of the Corporation to such 
amendment.

          4.   Upon notice in accordance with Section 222 of the General 
Corporation Law of the State of Delaware, a meeting of the stockholders was 
held.
     
          5.   Said amendment was duly adopted by the stockholders in 
accordance with the provisions of Section 242 of the General Corporation Law 
of the State of  Delaware.

               IN WITNESS WHEREOF, the undersigned has caused this Certificate 
of Amendment to be signed by Melvin D. Booth, its authorized officer.

Dated: May 23, 1997



                                   HUMAN GENOME SCIENCES, INC.

                                   

                                   By:   /s/ MELVIN D. BOOTH 
                                      ----------------------------------
                                       Melvin D. Booth, President



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