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                                                                     Exhibit 4.1

                  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. $0.0
  ------------------------
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 reorganization, 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 or 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(e)(i) of this Article I or, as applicable, Section 4(e)(i) of
       Article II, 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
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       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 26/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
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County of Suffolk
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     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 Gallant
                                             -------------------
                                             Notary Public

                                                                 (Notarial Seal)


My commission expires November 21, 2008
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