JOINT FILING AGREEMENT

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EX-99.1

                                                                      EXHIBIT I

                             JOINT FILING AGREEMENT



        In accordance with Rule 13d-1(k)(1) promulgated under the Securities
Exchange Act of 1934, the undersigned agree to the joint filing of a Statement
on Schedule 13D (including any and all amendments thereto) with respect to the
Common Stock, $0.01 par value, of Miravant Medical Technologies, and further
agree to the filing of this agreement as an Exhibit thereto. In addition, each
party to this Agreement expressly authorizes each other party to this Agreement
to file on its behalf any and all amendments to such Statement on Schedule 13D.



Dated:  April 10, 2000


                                        PHARMACIA & UPJOHN TREASURY SERVICES AB


                                        By: /s/ Xxxx Xxxxxxxx
                                           ------------------------------
                                           Name:  Xxxx Xxxxxxxx
                                           Title: Director


                                        PHARMACIA & UPJOHN COMPANY


                                        By: /s/ Xxx X. Xxxxxxx
                                           ------------------------------
                                           Name:  Xxx X. Xxxxxxx
                                           Title: Secretary


                                        PHARMACIA & UPJOHN S.p.A.


                                        By: /s/ Xxxxxxxxx Xxxxxxx
                                           ------------------------------
                                           Name:  Xxxxxxxxx Xxxxxxx
                                           Title: Managing Director





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                                           PHARMACIA & UPJOHN AB


                                           By: /s/ Xxxxx Xxxxxx
                                              -------------------------------
                                              Name:  Xxxxx Xxxxxx
                                              Title: Managing Director


                                           PHARMACIA & UPJOHN HOLDINGS B.V.


                                           By: /s/ Xxx Xxxxxx
                                              -------------------------------
                                              Name:  Xxx Xxxxxx
                                              Title: Director


                                           PHARMACIA & UPJOHN, INC.


                                           By: /s/ Xxx X. Xxxxxxx
                                              -------------------------------
                                              Name:  Xxx X. Xxxxxxx
                                              Title: Secretary


                                           PHARMACIA CORPORATION


                                           By: /s/ Xxx X. Xxxxxxx
                                              -------------------------------
                                              Name:  Xxx X. Xxxxxxx
                                              Title: Secretary