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                                    EXHIBIT A

                             JOINT FILING AGREEMENT

         The  undersigned  hereby agree that the  statement on Schedule 13G with
respect to the Common Stock of Boston Life Sciences,  Inc.,  dated as of January
15, 2002, is, and any amendments thereto (including  amendments on Schedule 13D)
signed  by each of the  undersigned  shall  be,  filed on  behalf  of each of us
pursuant to and in accordance  with the  provisions  of Rule 13d-1(k)  under the
Securities Exchange Act of 1934.


Date:  January 15, 2002             BROWN SIMPSON PARTNERS I, LTD.



                                    By:      /s/ PETER D. GREENE
                                             -----------------------------------
                                             Name:    Peter D. Greene
                                             Title:   Attorney-in-Fact


Date:  January 15, 2002             BROWN SIMPSON ASSET MANAGEMENT, LLC


                                    By:      /s/ PETER D. GREENE
                                             -----------------------------------
                                             Name:    Peter D. Greene
                                             Title:   Managing Principal