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                                                                     Exhibit 4.1

                                                                         [STAMP]

                 AMENDMENT TO THE CERTIFICATE OF DESIGNATIONS,
                            PREFERENCES, AND RIGHTS
                                       of
                           SERIES A PREFERRED STOCK,
                         SERIES B PREFERRED STOCK, AND
                            SERIES C PREFERRED STOCK
                                       of
                               GLYCOGENESYS, INC.

          We, Bradley J. Carver and John W. Burns, the President and the
Secretary, respectively, of GlycoGenesys, Inc., a corporation organized and
existing under the laws of the State of Nevada (the "Corporation"), in
accordance with the provisions of Section 78.1955 of the Nevada Revised
Statutes, DO HEREBY CERTIFY:

          WHEREAS, on June 22, 2001, the Board of Directors of the Corporation
(the "Board of Directors") adopted a resolution creating three series of shares
of preferred stock designated as the "Series A Preferred Stock," the "Series B
Preferred Stock," and the "Series C Preferred Stock"; and

          WHEREAS, the Board of Directors and the holders of the Corporation's
Series A preferred stock, par value U.S. $0.01 per share ("Series A Preferred
Stock"), Series B preferred stock, par value U.S. $0.01 per share ("Series B
Preferred Stock") and Series C preferred stock, par value U.S. $0.01 per share
("Series C Preferred Stock") desire to amend certain powers, preferences and
other special rights of the Series A Preferred Stock, Series B Preferred Stock
and Series C Preferred Stock.

          NOW, THEREFORE, pursuant to the authority conferred upon the Board of
Directors by the Articles of Incorporation of the Corporation and by Section
78.1955 of the Nevada Revised Statutes, on April 15, 2002, the Board of
Directors adopted, and holders of a majority of the Corporation's Series A
Preferred Stock, Series B Preferred Stock and Series C Preferred Stock approved,
the following resolution, amending and restating the Certificate of
Designations, Preferences, and Rights of Series A Preferred Stock, Series B
Preferred Stock and Series C Preferred Stock of the Corporation:

     "RESOLVED, that pursuant to the authority vested in the Board of Directors
     (the "Board of Directors") of GlycoGenesys, Inc., a corporation organized
     and existing under the laws of the State of Nevada (the "Corporation"), by
     the Certificate of Incorporation of the Corporation (the "Certificate of
     Incorporation"), the Board of Directors does hereby amend and restate,
     effective as of July 9, 2001, the designations, powers, preferences, and
     relative participating, optional, or other special rights, and the
     qualifications, limitations, and restrictions of the

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     Corporation's Series A Preferred Stock, Series B Preferred Stock and Series
     C Preferred Stock, as follows (respectively, the "Series A Designation",
     the "Series B Designation", and the "Series C Designation"):

     1.     Section 3(a) of Article I of the Certificate of Designations shall
be amended and restated in its entirety to read as follows:

     "(a)   Liquidation Events. The occurrence of any of the following events
     shall be deemed a "Liquidation": (i) any liquidation, dissolution, or
     winding-up of the affairs of the Corporation; (ii) any consolidation or
     merger of the Corporation with or into any other corporation or other
     entity or person, or any other corporate organization in which the
     stockholders of the Corporation immediately prior to such consolidation,
     merger or reorganization, own less than 50% of the outstanding voting
     securities of the surviving or resulting entity immediately after such
     consolidation, merger or reorganization (a "Merger Event"); (iii) any
     transaction or series of related transactions approved by the Board of
     Directors of the Corporation in which securities of the Corporation
     representing 50% or more of the combined voting power of the Corporation's
     then outstanding voting securities are acquired by a person, entity or
     group of related persons or entities, excluding any consolidation or merger
     effected exclusively to change the domicile of the Corporation; or (iv) any
     sale, lease, exclusive license or other disposition of all or substantially
     all of the assets of the Corporation."

     2.     Section 3(b)(iii) of Article I of the Certificate of Designations
shall be amended and restated in its entirety to read as follows:

     "(iii) After the distributions described in clause (b)(i) above have been
     paid, subject to the rights of any other class or series of capital stock
     of the Corporation that may from time to time come into existence, in the
     event of a Liquidation described in clause (i) or clause (iv) of Section
     3(a) of this Article I, the remaining assets of the Corporation available
     for distribution to stockholders shall be distributed among the holders of
     Common Stock, the holders of the Series A Preferred Stock, and the holders
     of any other class or series of capital stock of the Corporation entitled
     to share in such distribution pro rata based on the number of shares of
     Common Stock held by each, assuming conversion of any other class or series
     of capital stock of the Corporation convertible into shares of Common
     Stock."

     3.     Section 6(a) of Article I of the Certificate of Designations shall
be amended and restated in its entirety to read as follows:

     "(a)   On July 10, 2007, if any shares of the Series A Preferred Stock
     shall be outstanding, the Corporation shall redeem all outstanding shares
     of the Series A Preferred Stock, at a redemption price per share equal to
     the aggregate Series A Liquidation Preference, either (i) to the extent the
     Corporation shall have funds legally available for such payment, in cash,
     or (ii) by the issuance of shares of Common Stock with an

                                        2

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     aggregate Fair Market Value (as defined below) equal to such redemption
     price, in each case, together with any accrued and unpaid dividends thereon
     to the date fixed for redemption. For the purposes of this Section 6, and
     Section 4(e)(i) of this Article I and Sections 4(e)(i) of Article II, the
     "Fair Market Value" of one share of Common Stock shall be determined by the
     Board of Directors in good faith and certified in a board resolution
     (taking into account the most recently of concurrently completed arm's
     length transaction between the Corporation and an unaffiliated third party
     the closing of which occurs within the six months preceding or on the date
     of such calculation, if any) and shall be reasonably agreed to by a
     majority of the holders of the Series A Preferred Stock or, as applicable,
     the Series B Preferred Stock; provided, that in the event the Corporation
     and a majority of holders of the Series A Preferred Stock or, as
     applicable, the Series B Preferred Stock do not agree on the Fair Market
     Value the parties shall jointly appoint an independent third party
     appraiser to determine the Fair Market Value pursuant to the procedure set
     forth in Section 3(d) of this Article I; provided further, that in the
     event the Common Stock is traded on a securities exchange, the Nasdaq
     National Market or the Nasdaq SmallCap Market, the Fair Market Value shall
     be deemed to be the average of the closing sale prices for the Common Stock
     over the 30-day trading period (or such shorter period for which closing
     sale prices are available if the Common Stock commenced trading during such
     period) ending three (3) trading days prior to, in the case of this Section
     6, the date of notice of exercise of redemption pursuant to this Section 6,
     in the case of Section 4(c)(i) of this Article I or, as applicable, Section
     4(e)(i) of Article I, the date of the sale of Additional Shares that
     results in an adjustment to the Series A Conversion Price pursuant to
     Section 4(e)(i) of this Article I or, as applicable, the Series B
     Conversion Price (as defined in Article II) pursuant to Section 4(e)(i) of
     Article II; provided further, that for the purpose of this Section 6 the
     Fair Market Value shall be deemed to be at least $0.50 per share (the
     "Share Floor Price"). The Share Floor Price shall be proportionately
     adjusted for any stock split, stock combination or similar event affecting
     the Common Stock."

     4.     Section 3(a)(iii) of Article II of the Certificate of Designations
shall be amended and restated in its entirety to read as follows:

     "(iii) After the distributions described in clause (a)(i) above have been
     paid, subject to the rights of any other class or series of capital stock
     of the Corporation that may from time to time come into existence, in the
     event of a Liquidation described in clause (i) or clause (iv) of Section
     3(a) of Article I, the remaining assets of the Corporation available for
     distribution to stockholders shall be distributed among the holders of
     Common Stock, the holders of the Series B Preferred Stock, and the holders
     of any other class or series of capital stock of the Corporation entitled
     to share in such distribution pro rata based on the number of shares of
     Common Stock held by each, assuming conversion of any other class or series
     of capital stock of the Corporation convertible into shares of Common
     Stock."

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       5.  Section 3 of Article III of the Certificate of Designations shall be
amended and restated in its entirety to read as follows:

       "3. In the event of a Liquidation described in clause (i) or clause (iv)
       of Section 3(a) of Article I, whether voluntary or involuntary, the
       holders of Series C Preferred Stock shall have the right to receive, pari
       passu with the holders of the Common Stock and subject to the rights of
       the holders of any other senior class or series of capital stock of the
       Corporation, the assets of the Corporation in proportion to the number of
       shares of Common Stock held by each such holder (assuming, for such
       purposes, the holders of Series C Preferred Stock are deemed to hold that
       number of shares of Common Stock equal to the number of shares of Common
       Stock into which such shares of Series C Preferred Stock are then
       convertible)."


                            (signature page follows)

                                       4

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         IN WITNESS WHEREOF, said GlycoGenesys, Inc. has caused this Amendment
to the Certificate of Designations, Preferences and Rights of Series. A
Preferred Stock, Series B Preferred Stock and Series C Preferred Stock to be
signed by Bradley J. Carver, its President, and John W. Burns, its Secretary,
this 16/th/ day of April, 2002.


                                        GLYCOGENESYS, INC.


                                        By: /s/ Bradley J. Carver
                                            -------------------------
                                            Name:  Bradley J. Carver
                                            Title: President


                                        By: /s/ John W. Burns
                                            -------------------------
                                            Name:  John W. Burns
                                            Title: Secretary


State of Massachusetts
         -------------

County of  Suffolk
          ------------

         I. Richard Gallant a notary public, do hereby certify and attest that
the attached document is a true and exact copy of the Amended and Restated
Certificate of Designations. Preferences, and Rights of Series A Preferred
Stock, Series B Preferred Stock, and Series C Preferred Stock of the Company and
that on this 16/th/ day of April, 2002, personally appeared before me, Bradley
J. Carver and John W. Burns, who being by me first duly sworn, declared that
they are the President and Secretary of the Company, respectively, that they
signed the foregoing document as President and Secretary of the Company, and
that the statements therein contained are true.

                                        /s/ Richard A. Gallant
                                        -----------------------------
                                        Notary Public


                               RICHARD A. GALLANT
                                  Notary Public
                         Commonwealth of Massachusetts
                             My Commission Expires
My commission expires          November 21, 2002                        [STAMP]
                               -----------------