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                                                                     EXHIBIT 3.8

                            CERTIFICATE OF AMENDMENT
                             OF AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION
                              OF CYTEL CORPORATION

         Cytel Corporation (the "Corporation"), a corporation organized and
existing under and by virtue of the General Corporation Law of the State of
Delaware, does hereby certify:

         FIRST:   The name of the Corporation is Cytel Corporation.

         SECOND: The date on which the Corporation's original Certificate of
Incorporation was filed with the Delaware Secretary of State is July 10, 1987.

         THIRD: The Board of Directors of the Corporation, acting in accordance
with the provision of Sections 141 and 242 of the General Corporation Law of the
State of Delaware adopted resolutions at a meeting held on August 17, 1998 to
amend the first paragraph of Article V of the Amended and Restated Certificate
of Incorporation of the Corporation to read in its entirety as follows:

         "The Corporation is authorized to issue two classes of shares
         designated, respectively, "Common Stock" and "Preferred Stock." The
         total number of shares of all classes of stock which the Corporation
         has authority to issue is 85,000,000 shares, consisting of 75,000,000
         shares of Common Stock, each having a par value of $.01, and 10,000,000
         shares of Preferred Stock, each having a par value of $.01. Effective
         as of the close of business on November 13, 1998 (the "Effective
         Time"), each seven (7) shares of the Corporation's Common Stock, par
         value $.01 per share, issued and outstanding shall, automatically and
         without any action on the part of the respective holders thereof, be
         converted into one (1) share of Common Stock, par value $.01 per share,
         of the Corporation. No fractional shares shall be issued and, in lieu
         thereof, any holder of less than one share of Common Stock entitled to
         receive cash for such holder's fractional share based upon the closing
         sales price of the Corporation's Common Stock as reported on the Nasdaq
         National Market as of the date of the Effective Time."

         FOURTH: Thereafter, pursuant to a resolution of the Board of Directors,
this Certificate of Amendment of Amended and Restated Certificate of
Incorporation was submitted to the stockholders of the Corporation and was duly
approved by the required vote of stockholders of the Corporation in accordance
with Sections 228 and 242 of the Delaware General Corporation Law. The total
number of outstanding shares entitled to vote or consent to this Amendment was
34,909,187 shares of Common Stock and 258,378 shares of Series B Convertible
Preferred Stock. A majority of the outstanding shares of Common Stock and Series
B Convertible Preferred Stock, voting together as a single class, voted in favor
of this Certificate of Amendment of Amended and Restated Certificate of
Incorporation.





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         IN WITNESS WHEREOF, Cytel Corporation has caused this Certificate of
Amendment to be signed by its President this 10th day of November, 1998.



                                           CYTEL CORPORATION



                                           /S/ VIRGIL THOMPSON
                                           --------------------------------
                                           Virgil Thompson
                                           President and Chief Executive Officer





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