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                                                                    EXHIBIT 3.5

                           CERTIFICATE OF AMENDMENT
             OF AMENDED AND RESTATED CERTIFICATE OF INCORPORATION
                         OF BOSTON LIFE SCIENCES, INC

        PURSUANT TO SECTION 242 OF THE DELAWARE GENERAL CORPORATION LAW

          BOSTON LIFE 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:

          1.  The Amended and Restated Certificate of Incorporation of the
Corporation was filed in the office of the Secretary of State of Delaware on
March 29, 1996 and amendments thereto were subsequently duly filed and recorded
(the Amended and Restated Certificate of Incorporation together with such
amendments shall be hereinafter referred to as the "Certificate").

          2.  That the Board of Directors of the Corporation duly adopted
resolutions proposing and declaring advisable the following amendment (the
"Amendment") to the Certificate:

     RESOLVED, that the Board of Directors hereby approves and recommends to the
     Company's stockholders that the first sentence of Article FOURTH of the
     Certificate be, and it hereby is, subject to stockholder approval at the
     1999 Annual Meeting of Stockholders of the Corporation, amended and
     restated in its entirety to read as follows:

     "FOURTH: The aggregate number of shares which the Corporation shall have
     authority to issue is 31,000,000 to be divided into (a) 30,000,000 shares
     of Common Stock, par value $.01 per share, (b) 1,000,000 shares of
     Preferred Stock, par value $.01 per share, of which 13,404 shares are
     designated as Series A Convertible Preferred Stock, par value $.01 per
     share, with the powers, preferences and other rights as described on
     Exhibit A attached hereto and made a part hereof."

     FURTHER RESOLVED, that all other provisions of the Certificate, as
     heretofore amended, and all exhibits, attachments and certificates to the
     Certificate shall remain unchanged and in full force and effect, including
     but not limited to, all Certificates of Designation, Decrease and
     Elimination relating to the Corporation's Preferred Stock.

          3.  That thereafter a majority of the holders of the stock of the
Corporation entitled to vote thereon voted in favor of the Amendment at a
meeting of the stockholders duly held on June 28, 1999.

          4.  That the foregoing amendment to the Certificate of Incorporation
was duly adopted in accordance with the provisions of Section 242 of the General
Corporation Law.

          IN WITNESS WHEREOF, said Boston Life Sciences, Inc. has caused this
Certificate to be executed by its duly authorized officers this 28th day of
June, 1999.

                                    BOSTON LIFE SCIENCES, INC.

                                    By:   /s/ S. David Hillson
                                          --------------------
                                          Name: S. David Hillson
                                          Title: Chief Executive Officer